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01
81

REGIONAL STUDY

Sources and Movements of Water

An Interim Report
October 1973

New England River Basins Commission

For more information

and additional copies, contact:

New England River Basins Commission

270 Orange Street

New Haven, Conn. 06511

Tel: 203-772-0800 Ext. 6470

SOURCES AND MOVEMENT OF WATER
An Interim Report

Long Island Sound Regional Study

New England River Basins Commission

270 Orange Street

New Haven, Connecticut O65II

Prepared by the
U.S. Geological Survey, Water Resources Division

and the
National Oceanic and Atmospheric Administration

November 1973

FOREWORD

Long Island Sound is one of the nation's unique and irreplaceable natural re-
sources. An almost fully enclosed arm of the ocean, it has over 1300 square
miles of water surface and nearly a thousand miles of coastline. Spreading
eastward along both shores from the great metropolitan center which lies at
the Sound's western end, a growing concentration of increasingly affluent peo-
ple make ever greater demands on this urban sea. At the same time, there is
a growing feeling that the conflicting demands are destroying the Sound, and
that the problems must be resolved if the Sound is to be preserved.

The Long island Sound Regional Study is a comprehensive planning effort by
the federal government and New York and Connecticut, led by the New England
River Basins Commission. Assisting the Commission are professionals from
many disciplines representing the federal, state and regional agencies listed
on the back cover, a Citizen Advisory Committee, and a Research/Planning
Advisory Committee composed of members of the region's scientific community.

THE GOAL OF THE STUDY IS TO PRODUCE A PLAN OF ACTION BY JANUARY, 1975,
WHICH BALANCES THE NEEDS TO PROTECT, CONSERVE AND WISELY DEVELOP THE
SOUND AND ITS RELATED SHORELANDS AS A MAJOR ECONOMIC AND LIFE-ENRICHING
RESOURCE FOR THE 12 MILLION PEOPLE WHO LIVE NEAR IT.

This interim report is one of a series which outline demands placed on the
Sound, its capacity to supply these demands, and the present or expected
deficiencies to be overcome if it is determined that supply should meet de-
mand. The reports provide a base for developing single purpose management
plans which will evaluate the environmental and socio-economic impacts of
suggested alternative solutions and propose courses of action. These manage-
ment plans will be integrated into a comprehensive multi-purpose plan of con-
servation and development, reflecting relationships between types of demands
and setting forth goals and recommendations, the means for achieving them,
and a schedule of priorities. Interim reports in the series include:

Sources and Movements of Water

Water Q.ual i ty

Scenic and Cultural Resources

Mineral Resources and Mining

Soi 1 s

Erosion and Sedimentation

Ecological Studies

Water Supply

Recreation

Land Use and Ownership

Flood Plains

Electric Power Generation

Transportation

I I

SUMMARY

PURPOSE OF THIS REPORT. To summarize present knowledge about the sources,
distribution and movement of water in the Long Island Sound Region. Clima-
tological factors such as temperature, wind and cloud cover that affect
elements of the hydrologic system are also discussed.

HOW DOES WATER ENTER AND LEAVE THE SOUND?

Long Island Sound holds about 16, 800 billion gallons of water

but much more than this amount moves in and out each year estimated aver-
age quantities in billions of gallons a year (bgy) are:

\H OUT

Exchange with the ocean (east end) 64,000 79,800

Net Exchange through the East River (west end) 9,200

Runoff from streams 6,200

Precipitation on the Sound 800

Evaporation from the Sound 630

Diversions into the region 130

Ground-water outflow (Long Island) 100

Many of these estimates rest on incomplete or poor data more

accurate quantification is needed for planning and management.

WHAT ARE THE PRINCIPAL CLIMATIC FEATURES?

The climate of the Long Island Sound Region is characterized by:
four distinct seasons, little monthly variation in normal precipitation,
marked temperature contrasts over short distances, and the maritime influ-
ence which modifies air masses entering the region the climate may vary

appreciably from one location to another and from one year to another

distinctive climate events such as hurricanes, tornadoes, droughts and
blizzards occur in the region, resulting in floods, wind damage, crop
failure, and even loss of life.

WHAT IS THE HYDROLOGIC SYSTEM IN THE REGION?

The Region has an abundant supply of fresh water derived from

precipitation and from inflowing streams. of the total precipitation

falling on the land each year, about half returns to the atmosphere by

evapotranspi ration the remainder ultimately discharges to streams and

the Sound, either directly by overland flow or indirectly by downward per-
colation to the water table some 75 streams drain into Long Island Sound

they are hydraul ical ly connected to adjacent ground-water reservoirs and
are tidal in their lower reaches--the Connecticut, Thames and Housatonic

Rivers account for over 80 percent of total streamflow into the Sound

about 16,500 square miles of land drains into the Sound, only 12 percent of

this area is within the study region inflow is highest in the spring,

lowest in the summer.

I I

Long Island is underlain by a large ground-water reservoir of

generally good quality it meets almost all the Island's fresh water needs

the fresh and salty water systems are hydraul ical ly connected on the surface

and below it the yield of the fresh ground-water reservoir is not a single

fixed quantity; it will vary depending on hydrogeologic conditions, the
management scheme, and the extent to which undesirable effects of development

will be tolerated the mainland on the north shore of the Sound is underlain

by deposits of sand, gravel, silt and clay (stratified drift and till) and
bedrock the area contains many hydrological ly separate ground-water reser-
voirs of generally good quality large quantities of ground water may be

pumped from wells tapping stratif ied-drift deposits whereas most individual
domestic wells obtain adequate water from bedrock.

HOVI DOES SALT WATER CIRCULATE WITHIN LONG ISLAND SOUND?

Long Island Sound is a 1,300 square mile water body with estuarine
characteristics in its western and central parts and embayment characteristics

in its eastern third the minimum tidal range and maximum tidal currents

occur at the eastern end and the maximum tidal range and minimum tidal cur-
rents at the western end circulation is controlled principally by tidal

currents modified by fresh-water inflow, weather conditions and topography

the circulation pattern of surface and near surface waters is fairly well

defined, but relatively little is known about deep current circulation

surface tidal current patterns in the central and eastern Sound are ellipti-
cal and counter-clockwise in direction at the eastern end, surface water

flows into Block Island Sound, while more dense and saline bottom waters

flow into Long Island Sound at the western end, surface water from the East

River flows into the Sound and bottom waters move into the East River

movement of water within major estuaries is complex because of the effects

of tides and fresh-water inflow conditions understanding this movement is

important for water management.

WHAT WILL THE STUDY DO NEXT?

It will work on solutions in all management areas information

from this report and its supporting studies should be reflected in the
solutions, especially for water quality, water supply and flooding pro-
posals will be made to resolve major knowledge gaps such as the quantifica-
tion of the dynamic circulation system within the Sound and its major
estuaries.

IV

TABLE OF CONTENTS

Page

FOREWORD ii

SUMMARY i i i

TABLE OF CONTENTS v

1. INTRODUCTION 1

2. HYDROLOGIC FRAMEWORK OF THE LONG ISLAND SOUND REGION 1

3. CLIMATOLOGY 6

Weather systems 7

Availability of cl imatological records 7

Temperature 8

Precipitation 10

Tropical storms and hurricanes 12

Thunderstorms 13

Tornadoes 1^

Cloud i ness ]k

Wind ]h

Drought 17

k. FRESH SURFACE-WATER BODIES 18

Availabil i ty of data 19

Fresh water inflow to Long Island Sound 19

Coastal streams 22

Annual maximum streamf lows 22

Lakes and ponds 2k

5 . GROUND WATER 2k

Availability of hydrogeologic data 2k

The hydrogeologic system of Long Island 2k

The hydrogeologic system on the north shore of Long

Island Sound 32

6. BRACKISH AND SALT WATER BODIES 37

Aval labi 1 i ty of data 38

Circulation and movement 38

Estuaries k2

7 . WHAT THE STUDY W I LL DO NEXT kk

Appendices

A - Selected References A-1

B - Glossary B-1

C - Hydrologic and Climatologic Maps, Graphs and Tables

prepared for the Long Island Sound Regional Study C-1

D - Location of Stations used in Long Island Sound Region

Cl imatological Analysis D-1

E - Summary of Discharge Records for Mainland Streams E-1

Digitized by the Internet Archive

in 2010 with funding from

Boston Library Consortium IVIember Libraries

http://www.archive.org/details/sourcesmovementoOOgeol

1.0 INTRODUCTION

The purpose of this report is to summarize present knowledge
about the sources, distribution and movement of water in the Long Island
Sound Regional Study Area. Cl imatological factors such as temperature,
wind and cloud cover that affect elements of the hydrologic system and in
turn development patterns are also discussed.

Water sources, the quantity stored at any time above or below the
ground, the pattern of water movement and water quality are of direct con-
cern to a variety of interests within the region. Flood control, water supply,
waste disposal, recreation, agriculture, transportation and power generation
are some examples of activities that are water dependent or water related.
Man-made changes in land use, such as urbanization, alter the natural hydro-
logic system and coordinated water and land use planning is therefore
essential. Conversely, too little or too much water can limit development
or require large costs to support growth.

The information in this report together with supporting studies
and data listed in appendices A and C will be used in the plan formulation
phase of this study. The scope of subsequent planning must take into con-
sideration (1) the existing requirements, interrelationships and often con-
flicts between various groups of water users and how they will change with
time and (2) the effect on the hydrologic system of alternative water and
land use practices.

2.0 HYDROLOGIC FRAMEWORK OF THE LONG ISLAND SOUND REGION

Within the framework of the hydrologic cycle, water continually
moves between and is temporarily stored in the atmosphere, on and below the
land, and in the ocean. Water enters the Long Island Sound Region from (1)
precipitation directly on the land or water within the region (2) as runoff
from adjacent land areas that drain into the Sound (3) from Block Island
Sound to the east and the East River to the west and (k) from sewage treat-
ment plants that process water from outside of the Long Island Sound drain-
age area. Water leaves the region by (1) evaporation and transpiration into
the atmosphere or (2) by outflow into Block Island Sound and perhaps into New
York Harbor. This general pattern of circulation and the average quantities
of water involved are shown on Figure 1.

The hydrologic conditions are largely governed by the climate
within and adjacent to the region. Located between the source regions of
warm moist air and of cold dry air places the study area near the principal
west to east storm tracks. Furthermore, coastal storms originating in the
ocean off the southeastern United States frequently travel on courses that
bring them nearby.

PRECIPITATION
ON LAND

DIVERSIONS ^

^^ ^

'T?

INFLOW FROM
EAST RIVER
9,200 bgy +

GROUND-WATER
DISCHARGE L I

750 bgy

630bq,

/'

EXCHANGE WITH
BLOCK ISLAND SOUND
INFLOW 64.000 bgy
OUTFLOW 70,600 bgy
9.200 bgy *

EVAPORAl ION

EVAPOTRANSPIRATION

% NET INFLOW FROM EAST RIVER OF 9, 200 bgy may be s,gnilicenlly in error.

Figure 1. General pattern of water circulation and estimated average quan-
tities of water involved in billions of gallons per year (bgy). Blocks
drawn to scale. The water volume in the Sound itself is approximately
16,800 bi 11 ion gal Ions.

Passing storms bring clouds, wind, rain and snow. Average
annual precipitation in the Long Island Sound Region ranges from approximately
36 to 51 inches (1.7 to l.k million gallons per day per square mile) and has
fairly equal monthly distribution. The minimum average annual precipitation
over the land, 38 to kk inches, occurs along the north shore of Long Island
and the south shore of Connecticut between Norwalk and Guilford. The maxi-
mum over Long island, kh to 48 Inches, occurs along an east-west axis
centered near Lake Ronkonkoma, and in Connecticut, 46 to 51 inches, over

northern parts of the study area. Assuming the average annual precipitation
is approximately kS inches on the 19^0 square miles of land and 36 inches on
the Sound the Long Island Sound Region receives approximately 2,300 billion
gallons of water each year in the form of rain and snow.

The precipitation that falls on the land under natural conditions
is either returned to the atmosphere by evaporation and transpiration (evapo-
transpi ration) or flows across the land and through subsurface materials to
stream channels, estuaries and the Sound. The average annual evapotranspi ra-
tion is approximately one half of the average annual precipitation. Almost
all evapotranspi rat ion occurs in the growing season (April through October)
when plants use a large amount of water, temperatures are above freezing and
hours of daylight are longest.

The water that is not evapotranspi red either flows over the land
surface, to streams (direct runoff) or infiltrates downward through the
various earth materials eventually reaching the saturated zone. Most of the
subsurface water in the saturated zone, termed ground water, moves toward
and discharges into stream channels, estuaries and the ocean. The total
fresh water runoff into Long Island Sound is the sum of the direct runoff
and ground-water discharge from the entire Long Island Sound land drainage
area of approximately 16,500 square miles. The average annual total runoff is
approximately 6,200 billion gallons per year (bgy) or 5.5 cubic miles of
water as computed by the U.S. Geological Survey.

The average annual runoff into Long Island Sound is almost three
times as large as the average annual precipitation within the study region.
Water quality, flood control and sedimentation are therefore significantly
affected by natural events and man's activities in the large 1U,500 square
mile drainage area north of the region boundary.

Long Island contrasts sharply with the land on the north shore
of the Sound in respect to the pattern of water circulation. Long Island is
underlain by a wedge-shaped mass of unconsolidated sediments that rests on a
gently southeast-sloping surface of relatively impermeable bedrock. The
saturated zone beneath Long Island constitutes a large ground-water reservoir
containing in excess of 60 trillion gallons of fresh ground water (5).' The
fresh and salty ground water and fresh and salty surface water are hydrau-
lically connected and Long Island both within and out of the study region is
an integrated hydrologic system.

Because Long Island is relatively flat and the surface materials
are permeable almost all the precipitation not consumed by evapotranspi ra-
tion percolates down to the saturated zone. Only 5 to 10 percent of the
streamflow consists of direct runoff and the ground water and surface drain-
age divides are not coincident. The ground water beneath Long Island is
constantly moving vertically downward and horizontally toward the shores

1 - Underlined numerals in parentheses are references in Appendix A.

from the ground-water drainage divide near the center of the island. About
half of the ground-water discharge is subsurface outflow into Long Island
Sound and the Atlantic Ocean, the rest is discharged to streams and springs
or evapotranspi red from the upper part of the saturated zone. Figure 2 shows
the pattern of water circulation on Long Island under natural conditions.

Fresh ground water

Salty ground water

Figure 2. Block diagram illustrating ground-water movement and discharge on
Long Island, New York under natural conditions. After Cohen and others
(1968 pi. kF).

The land on the north shore of Long Island Sound is underlain by
bedrock at relatively shallow depth. The surface is di scont i nuously covered
by unconsolidated deposits composed of sand, gravel, silt and clay. Major
surface-water and ground-water drainage divides are coincident and the area
hydrological ly consists of a number of separate ground-water reservoirs each
drained by a perennial stream and extending from one drainage divide to another.
The amount of water stored in and moving through the saturated zone varies in
each basin because of differences in size and type and distribution of sub-
surface materials.

Direc
cipal 1y because o
the surface mater
del i neated drai na
from the drainage
ground-water disc
62 percent of the
charge in coastal
3 shows the gener
the north shore o

t runoff constitutes a high proportion of streamflow, prin-
f the topography and relatively low permeability of much of
ials. Ground-water circulation is generally confined within
ge basins and the direction of ground-water movement is away

divides and toward major streams and estuaries. Most
harge is to streams and where computed (4) ranges from 28 to
total annual runoff. A small amount of ground-water dis-
areas is subsurface outflow into Long Island Sound. Figure
al pattern of water circulation in a major drainage basin on
f the Sound.

-Drainage Divide

MAJOR GROUND - WATER FLOW SYSTEM

WEST

EXTENT

OF MINOR FLOW

SYSTEM

Drainage Divide -

EAST

^^\^r:

a

' / i

</ / CD

Figure 3. Idealized section illustrating ground-water movement and dis-
charge on the north shore of Long Island Sound. After Cervione and others
(1968, Fig. 33).

The direction of ground-water movement is shown by flow lines. Ground-
water discharge consists of (1) seepage to streams and (2) ground-water
evapotranspi ration.

Long Island Sound is an approximately 1300 square mile embayment
bounded on the south by Long Island and on the north by the New York and Con-
necticut shorelines. The eastern third may be thought of as an extension of
the continental shelf, whereas the central and western parts are more analo-
gous to an estuary. The eastern end of the Sound is generally considered to

extend from Watch Hill Point in Rhode Island to Orient Point on Long Island
while the western boundary extends from Throgs Neck to Willets Point. Using
a slightly different eastern boundary (extending from Orient Point, Long
Island through Plum Island, to Race Point on Fishers Island and thence to
Groton Long Point) the National Ocean Survey computed the volume of water in
the Sound to be approximately 16, 800 billion gallons or 15.^ cubic miles.

The average annual fresh water inflow as previously stated is
approximately 6,200 billion gallons, equal to 37 percent of the total volume.
Most of the fresh water inflow (80 percent or more) is into the eastern end
of the Sound from the Connecticut and Thames Rivers. Assuming that the aver-
age annual precipitation is 36 inches, an additional 800 billion gallons a
year of fresh water falls directly on the Sound.

Riley (29) , Swanson {33) f LeLacheur and Sammons (50) and others
have described the general pattern of circulation. The dominant horizontal
motions are the semidiurnal tidal currents; reversing currents occur along
the coast while in central Long Island Sound the currents are elliptical.
The mass transport pattern is the eastward movement of waters in the surface
layer out of Long Island Sound and the westward movement of bottom waters
into Long Island Sound from Block Island Sound (29) . The volume of fresh
water drainage controls the exchange and the annual total inflow of saline
water along the bottom is equal to 3.8 times the volume of water in the Sound
(29) . Although the tidal circulation pattern of surface and near surface
waters is known, relatively little information on deep current circulation is
avai 1 able.

Limited exchange of water is believed to occur between the western
end of Long Island Sound and New York harbor. The net inflow from the East
River into western Long Island Sound has been estimated to be as high as 1,100
cubic meters per second (9,200 billion gallons per year), but recent studies
(11) indicate that this estimate may be too high by an order of magnitude.
The only other outflow is evaporation from the Sound to the atmosphere esti-
mated to be 630 billion gallons per year, slightly less than the precipitation
on the Sound.

3.0 CLIMATOLOGY

The unique features of the climate of the area surrounding Long
Island Sound are: four distinct seasons; a variety of precipitation types
but with little monthly variation in normal precipitation amounts; marked
temperature contrasts over short distances; and the maritime influence which
modifies the air masses that affect the area. The climate varies from one
location to another and from one year to another. There has been, for
example, a winter season with only 10 inches of snow in the northern part of
the region and another winter season with over 80 inches of snow in coastal
Connecticut; a record daily maximum temperature at a northern location of
10'4°F and a record February minimum near the coast of -24°F; Octobers with
almost no rainfall and a single October day in which nearly 10.5 inches of
rain fell at one location.

3. 1 Weather systems

In winter, polar-continental air dominates the region resulting
in many clear, dry and bright days. Daily mean temperatures are generally
below freezing from mid-December through early March except for a shorter
period along the shore. Pacific air masses frequently reach the area during
the winter resulting in somewhat higher temperatures and humidities. Occa-
sionally tropical air reaches the Sound area in the winter. Because of its
lower density the tropical air usually overrides the colder air from the
north but at times it reaches the surface causing the well known "January
thaw."

In summer, air from the Gulf of Mexico and the tropical Atlantic
brings high temperature and humidity. In crossing the Sound from the south-
west this air mass may be cooled from below creating pollution-trapping
inversions along the Connecticut shore. The hazy skies may clear up after
midday if the inversion is destroyed, but when the sea breeze prevails or if
the flow is more southerly stable conditions may remain into the evening
and longer. Air of Pacific origin traveling eastward from the Canadian north-
west brings bright skies and relief from haze and pollution associated with
the tropical air.

North Atlantic source region air also reaches the area in the
summer resulting in cooler temperatures and frequently steady light precipi-
tation. Polar continental air, modified by intense solar heating, occa-
sionally moves into the area in summer while hot dry continental air from
Arizona and New Mexico infrequently reaches the area during this season.
Spring and autumn are periods of transition characterized by rapid alterna-
tion of air masses and fast changes in weather patterns.

Winter storms frequently move into the region from the area near
Cape Hatteras, N.C. During the remainder of the year storms develop further
east and north over the Atlantic Ocean and further north over the Great
Lakes. The period August through November is characterized by occasional
tropical disturbances.

Air masses undergo temperature and humidity changes when they
move over the Ocean and Sound, travel over snow covered ground or are lifted
over hilly terrain. The presence of the Sound provides one of the major
climatic controls for the area in that it acts as a vast reservoir for the
storage and subsequent exchange of heat energy with the atmosphere.

3.2 Availability of cl imatoloqical records

Reliable records date back to 1778 at New Haven, Connecticut and
for shorter periods elsewhere in the Long Island Sound Regional Study Area.
Comprehensive analysis of cl imatological data for selected time periods are
available in: The Climate of Connecticut (3.)", The Precipitation Regime of
Long Island, N.Y. (J2) ; The Climatic Guide for New York City, N.Y. and Near-
by Areas (U6) ; and Climates of the States, New York (kj) .

CI imatological records for existing stations in and near the
study area are published each month by the National Weather Service (18) .
Short and long-period weather forecasts for the area are regularly furnished
by offices of the National Weather Service in New York City, N.Y., Windsor
Locks, Conn, and Bridgeport, Conn.

As part of the Long Island Sound Regional Study, the cl imatolog-
ical data for the period 1951-1970 together with selected long-period infor-
mation was inventoried and analyzed by the National Weather Service. Most
data was obtained from the archives of the National Climatic Center, Ashe-
ville. North Carolina. The existing records are of good quality and areal
distribution, except for the area directly over Long Island Sound, Records
from all stations in New England and parts of eastern New York were used to
evaluate monthly and water year precipitation, whereas the balance of the
cl imatological analyses are based on data from 15 stations supplemented
where necessary by additional stations. The locations of the principal and
supplementary stations are shown in Appendix D.

Approximately 100 tables, graphs and maps prepared for the Long
Island Sound Regional Study are listed in Appendix C of this report. They
depict averages, extremes, ranges and variability in time and space of
climatic events or contain statistics on frequency, variability and probabil-
ity. Because of the scope of available information only brief descriptions
of specific climatic phenomena are contained in this report. Therefore, in
the sections that follow the objective is to apprise the report user of what
information is available on specific topics such as temperature and precipi-
tation.

3.3 Temperature

The mean annual temperatures generally decrease eastward from
New York City, inland from the Connecticut shoreline and from the interior
toward the shore on Long Island. Mean annual temperatures for the region
range from kS to 55°F, are lowest in eastern Connecticut, northern portions
of southwestern Connecticut and in eastern Long Island and are highest in
western and central Long Island. Maps showing the geographic distribution
of mean annual temperature and mean annual temperature range are listed in
Appendix C. Mean annual temperature has little significance in an area where
daily ranges vary from 10 to 25°F and annual ranges vary from ]k to 23°F.

Monthly mean-maximum, mean-minimum and mean temperatures have
been tabulated for the region (see Appendix C) and provide a basis for pre-
dicting future temperatures. Monthly mean-maximum, mean-minimum and mean
temperatures all trend in a latitudinal direction except where topography
and the influence of the Sound predominate. The moderating influence of
Long island Sound is best defined in late spring and summer when water tem-
peratures are cooler than air temperatures and in late autumn and winter when
water temperatures are generally warmer than air temperatures.

A water year is the continuous 12-month period, October 1 through
September 30. It is designated by the calendar year in which it ends.

. 8

In certain economic undertakings a knowledge of the frequency of
climatic events is required before decisions involving risks are implemented.
Tables, listed in Appendix C present the monthly and annual greatest, least
and mean numbers of days of occurrence of maximum temperatures equal to or
below 32 and 45°F and equal to or above 80 and 90°F and minima equal to or
below if5, 36, 32, 24, 16 and 0°F.

The observed variations clearly demonstrate the difference in
climate between northern Long Island and southern Connecticut; between
interior sections and coastal areas; and between western and eastern parts
of the region. In summer, temperatures of 90°F or higher occur most frequent-
ly over inland areas of southern Connecticut and in western portions of the
region and least frequently along the eastern perimeter of Long Island Sound.
These temperatures also occur less frequently along the coastal section and
more often on northern Long Island than in southern Connecticut. In winter
temperatures below 16°F are 2 to 3 times more likely in southern Connecticut
than northern Long Island and occur frequently at short distances from the
coast in Connecticut. For example, the average annual frequency of days with
maximum temperatures of 90°F or higher is 9 at Riverhead, Long Island, 16 at
LaGuardia Field, New York, but at New Haven, Connecticut, it is 3 and at
Scarsdale, New York, 22. Days with minimum temperatures of 16°F or lower
usually occur 15 times a year at Riverhead, 11 at LaGuardia, 22 at New Haven,
2k at Scarsdale and 30 to 36 in the interior of southern Connecticut.

Design data for heating and air conditioning were tabulated for
four stations. The data included: the dry and wet bulb temperatures that
are exceeded 10, 5, 2-j and 1 percent of the time, the number of hours that
dry bulb temperatures of 93, 80, 73 and 67°F and wet bulb and dew point
temperatures of 80, 73 and 67°F are equaled or exceeded through the warm
season; and the temperatures which are reached or surpassed 97.5 and 99 per-
cent of the time during the cold season. Monthly and seasonal cooling and
heating degree-day data for 14 stations are also contained in tables listed
in Appendix C.

Freeze statistics are employed in agriculture to choose areas
suitable for special cropping, to design planting schedules and to make long-
range management decisions. The longest average annual freeze-free season,
190-205 days, along the shore areas of Connecticut and Long Island is similar to
the freeze-free period in northern Alabama and Georgia. A sharp gradient--
40 days within 10 mi les--general ly exists between coastal and interior valley
stations in Connecticut. Tables giving the 95, 90, 75, 50, 25, 10 and 5
percent probability dates for the last occurrence of 32, 2k and 16°F or
lower temperatures in spring and the first occurrence date of the same tem-
peratures in the fall have been prepared for this study.

The Sound produces a longer growing season along its shores even
though the cooler ocean waters in early spring retard the start of the grow-
ing season. As the Sound begins to act as a heat source in fall, the length
of the season is significantly extended along the shores of both Long Island
and western Connecticut. The largest reduction in heat available for growing
occurs in eastern coastal areas of Connecticut where cold water lowers the
daily mean temperatures during most of the growing season.

3.^ Precipi tation

Precipitation near and within the Long Island Sound Region
results from a variety of causes including tropical storms, air mass
thunderstorms and extra-tropical low pressure areas. The amount and
areal distribution of precipitation for water years 19^1-70 has been compiled
for the entire Long Island Sound drainage area by the National Weather Ser-
vice. Over the study region itself the average annual precipitation ranges
from 36 to 51 inches. About 5 to 20 percent of the annual total precipitation
is snowfall with maximum amounts in northern sections. The average annual
precipitation is greatest near the slightly elevated part of Long Island and
away from the immediate shore in Connecticut. Two factors affect the geo-
graphic distribution of precipitation: distance from the stabilizing influence
of water bodies and differences in altitude.

Besides the amount and areal distribution of precipitation, infor-
mation on the intensity and duration of precipitation is required for many
purposes. For example, the extreme 24-hour precipitation event at New Haven
was 8.73 inches on August 8-9, 187^. This knowledge is useful, but short-
period excessive rainfalls are sometime even more important. Rainfalls of
1.38 inches in 10 minutes and 2.3^ inches in 30 minutes at New Haven on July
2k, 1928 are examples of precipitation events which caused serious stresses
on engineering works. Listed in Appendix C are (1) a table based on Hersh-
field (13) which gives maximum point-precipitation amounts for selected dura-
tions from 5 minutes to 2k hours and return periods from 2 to 100 years and
(2) a table listing the monthly extreme 2A^-hour precipitation and snowfall
together with their years of occurrence and (3) a listing of the mean monthly
24-hour extremes of the data and their standard deviations.

Long-term precipitation records for New Haven, Connecticut, New
London, Connecticut, and Setauket, Long Island are shown in 6 graphs (see
Appendix C) . Three of the graphs permit calculation of the frequency with
which a given amount of precipitation can be expected at each location. For
example, the chances are that 80 percent of the time water-year precipitation
at Setauket will be equal to or greater than 39 inches but only 1 in 100 that
it will be as little as 32 inches.

Tables which give the least and greatest recorded monthly and
annual precipitation amounts, together with their years of occurrence, are
listed in Appendix C. These tables show, for example, that annual calendar
year precipitation has varied locally from 25.35 inches at New London, Con-
necticut, in 1863 to 78.37 inches at Lake Konomoc near Waterford, Connecticut
in 1972. Three additional tables list the mean, greatest and least monthly
and annual number of days with precipitation equal to or greater than 0.01,
0.10, 0.50 and 1 .00 inches.

Mean and greatest monthly and mean seasonal snowfall for the
1951-70 period are listed in a table (see Appendix C) . Average seasonal
snowfall on the north shore of Long Island ranges from about 23 to 28 inches.
Along the mainland coast, the amounts vary from 26 to 33 inches with the
larger totals between New Haven, Connecticut and Westbrook, Connecticut. Snow-
fall increases rapidly away from the coast and in the more hilly portions of

the mainland interior the averages range from 39 to 49 inches. The geographic
distribution of snowfall based on the tabular data is shown on the figure
below. Large variations may occur within short distances in the hilly sec-
tions, so that for these areas the map should only be used as a guide.

Figure k. Mean annual snowfall in inches over the Long Island Sound Region,
January 1951 to December 1970.

Four of the tables listed in Appendix C give the mean and greatest
monthly and annual number of days with snowfall equal to or greater than 1,
2, k and 8 inches. Since there are many years without snowfalls of k inches
or more in the region, only two tables for the least number of snowfalls equal
to or greater than 1 and 2 inches were prepared.

Snow cover data from 13 stations in and north of the study area,
presented in maps and tables give (1) the mean, maximum and least number of
periods per season of 3 days or longer with snow depth equal to or greater
than 1 and 6 inches; (2) the mean, median, maximum and minimum number of days
involved and (3) the mean, median, greatest and least days per period. The
tables also provide information of the first day-first period and last day-
last period dates for various probability levels.

11

3.5 Tropical storms and hurricanes

Tropical storms (maximum winds of 39 to 73 miles per hour) and
hurricanes (maximum winds of Jk miles per hour or more), exist as part of the
general atmospheric circulation. In well developed hurricanes^ the speed of
the maximum winds near the center of the storm can reach 200 miles per hour
(mph) or more in the tropics, but in the Long Island Sound Region surface winds
probably have never exceeded 150 mph. Tides along the perimeter of the Sound
may reach 10 feet above normal in intense hurricanes. The accompanying pre-
cipitation is both beneficial and harmful, supplying needed moisture for crop
development if amounts are moderate, but causing damaging floods if precipi-
tation amounts are excessive. Torrential rainfall over a considerable area
is a common feature of tropical cyclones of all intensities including tropi-
cal depressions (winds less than 39 mph). In fact, some of the less violent
storms are the greatest flood producers because they sometimes linger over
the region for days.

Figure 5.
Region.

Tracks of hurricanes with first landfall on the Long Island Sound

12

At low latitudes, tropical disturbances usually move with the
flow around the large permanent subtropical anticyclones. Existing circu-
lation patterns associated with transient mid-latitude weather systems
increasingly influence the motion of tropical cyclones when they migrate
toward higher latitudes. Here tropical cyclones may be modified by inter-
action with nontropical air although winds may remain above hurricane force
in some cases.

During the period 1871-1972 a total of 63 disturbances of tropi-
cal origin passed within about 150 miles of the Long Island Sound Region.
Sixteen of these storms passed directly over the area and four hit Long Island
and Connecticut from the ocean without prior landfall. The endless variety
of tracks is a reflection of the continual changes in pattern of the general
circulation during the period when tropical cyclones are in existence. Figure
5 charts the paths of the four hurricanes which hit the region directly from
the sea.

The time-frequency distribution of tropical storms and hurricanes
in the study region is such that no cl imatological summary can be considered
a stable assessment of the risk of recurrence of these storms in any locality.
Nevertheless, it is important that the best possible information be available
for planning purposes. A table, listed in Appendix C and modeled after Crutcher
and duinlan (15) indicates the percent probabilities with which the center of
an existing tropical cyclone at a specified latitude and longitude can be
expected to be within the Long Island Sound Region after 72, k8 and 2k
hours. The greatest probability of occurrence in the region after 2k hours
is about 1 in 5 during August for a tropical cyclone located at 35 .5°N and 77 . 5°W.
If the current position of the storm were at the same longitude but 5° farther
south the probability that the storm center would be within the Long Island
Sound Region after 2k hours reduces to 1 in 50 but for occurrence in the
region after k8 hours the chances again increase to 1 in 13.

Although the chance that an individual tropical cyclone will di-
rectly hit the region is relatively low, the percentage "strike probability"
in any one year is considerably higher — nearly 16 percent for a direct hit
and about 60 percent for an occurrence within 150 miles of the area. The
region was rarely subject to hurricanes between 1901 and the massive hurri-
cane of 1938 but was severely affected several times since, notably in 19^^^
195^, 1955 and i960. The planner should be aware of the effects of intense
winds, torrential rainfall and high storm surges produced by these severe
hurricanes on a highly developed area not geared to such disasters.

3 .6 Thunderstorms

Thunderstorms commonly result in damage to crops and property.
In the region the number of days with thunderstorms varies markedly through-
out the year from a low of less than one day per month in winter to 5 to 8
days per month in summer. The greatest annual total, 20 to 25, occurs in
southwest Connecticut, central Long Island and around heavily populated urban
areas. The smallest number, approximately 1^, is recorded in eastern Long
Island and southeastern Connecticut. The frequency of thunderstorm occurrence
is related to distance from water, altitude and perhaps air pollution in
industrial areas.

13

Two maps have been prepared (see Appendix C) that show the mean
and maximum annual number of thunderstorms in the region. Generally the mean
number of thunderstorms increases from east to west and inland from the shore,
with the smallest number occurring in eastern Connecticut and eastern Long
I sland.

3.7 Tornadoes

Tornadoes occasionally develop in air mass or pre-frontal thunder-
storm areas during the afternoon or evening. Most tornadoes in the region have
occurred in southwestern Connecticut and the risk of their occurrence decreases
eastward because of the stabilizing effect of the Sound. A table is furnished
(see Appendix C) that chronologically lists all known tornadoes in the region
since 1682.

3.8 Cloudiness

Cloud cover averages computed over the full day for the period
1951-70 are available from LaGuardia Field, New York and for the pet iod 1951-
69 from Westhampton Beach, New York. The annual march of mean cloudiness in
tenths for these two stations is shown on a graph prepared for this study (see
Appendix C) . Mean monthly cloudiness for the sunrise to sunset period for
Bridgeport, Connecticut and for k stations near the study area--Block Island
and Providence, Rhode Island; LaGuardia Field, New York and Hartford, Con-
necticut are shown on a separate graph.

Annual mean sky cover averages about 60 percent over the study
region, but there is considerable variation both in time and space. Cloud
amounts over mainland interior areas are generally greater than over coastal
sections except from June through September. Western mainland interior areas
have greater cloud amounts than eastern areas whereas along the coasts cloudi-
ness is generally greater in the east than in the west. The greatest number
of clear days throughout the region occur in September and October.

Comparisons among stations point out the influence of season and
the proximity to the Sound and Ocean on sky cover. Graphs have been pre-
pared for four stations to illustrate the controls operating on sky cover.
The graphs show the annual march of mean cloudiness and the percentage fre-
quencies for two classes of sky cover for the hours from 6 a.m. to 8 p.m.
(See Appendix C.)

3.9 Wind

The frequency distribution of the occurrence of wind direction
and speed reflects the passage of weather systems, the distribution of land
and water and the local exposure. Wind data in the Long Island Sound Region
are available for LaGuardia Field, New York and Bridgeport and New Haven, Con-
necticut. Data for Newburgh and Westhampton Beach, New York have also been
used for this study. All weather wind-rose diagrams for each of the four
seasons at these five stations are listed in Appendix C.

14

Around the Sound, west-northwesterly winds prevail in winter with
the wind blowing from west to north 52 percent of the time, the most persist-
ent wind of any season. Mean speeds averaged over all directions range from
8 to 12 knots (9.2 to 13.8 mph), but the strongest winds are northwesterly,
averaging between 11 and 16 knots (12,7 to 18.4 mph) over the entire season.

Spring is a time of variable wind with frequent changes in weather
control. Northwesterly winds prevail in western portions of the region, but
southwesterl ies begin to assert themselves gradually in more easterly sections.
The mean wind speed for the season ranges from 9 to 1 1 knots (10.3 to 12.7
mph) but strongest winds range from 11 to ]k knots (12.7 to 16.1 mph) and are
from the northwest.

Southwesterly winds prevail in the summer as the flow is most
frequently dominated by the high pressure area which extends into the south-
eastern United States from the Atlantic Ocean. Southwesterly winds occur
from ]h to 20 percent of the time although there is considerable alternation
from south to west-southwest and sometimes east. Mean wind speeds over all
directions range from 7 to 9 knots (8.1 to 10.3 mph).

Winds in the autumn reflect the transition from summer to winter
in both speed and direction. Cyclonic activity begins to increase and pre-
vailing winds gradually shift from southwesterly to northerly directions,
ranging between northwest and northeast except in extreme easterly sections
where the southwesterly winds continue longer into the season. Mean speeds
averaged over all directions range from 7 to 10 knots (8.1 to 11.5 mph) and
show a gradual increase through the season.

In general the Sound and Atlantic Ocean have a dampening effect
on hot summer winds and the Sound has an accelerating effect on cold winds
from the mainland in winter. When anticyclonic conditions prevail on the
mainland in winter, the wind frequently reaches the northern shore of Long
Island with much higher velocities than occur over Connecticut. Since the
Long Island Sound Region lies well south of the northern storm track and
north of the path usually followed by the southern storms, wind movement is
not as great as it is in these areas. Winds of gale force are seldom expe-
rienced. Many times when areas east of the region are lashed by violent
coastal storms, only moderately high winds are experienced. Occasionally,
however, when a storm or hurricane moves up the coast or when a storm from
the Great Lakes moves southeastward, destructive winds occur throughout the
Long Island Sound Region.

In designing large structures, it is necessary to take wind pres-
sure into account. Estimates of the distribution of extreme wind speeds
likely to be experienced once in 50 years and once in 100 years have been
prepared for the entire United States by H. C. S. Thorn (35) . These estimates
are based on winds 30 feet above the ground, but can readily be adjusted to
other elevations. For the 50-year return period, values of 65 to 80 mph are
estimated for Connecticut, increasing from the northwest toward the south-
eastern coast. The extreme wind speed to be expected once in 100 years ranges
from 80 to 90 mph in the interior and along the southwestern coast to close
to 100 mph in the extreme southeast.

15

3.10 Drought

Drought has many different meanings and definitions vary widely.
For example, it may be termed an agricultural drought when precipitation is
inadequate to maintain the moisture content of the soil at optimum levels
thereby affecting agricultural production. To others, droughts are character-
ized by more severe precipitation deficits that persist to the degree that
streamflow and ground water and thereby man's water supply are affected. A
satisfactory definition for the Long Island Sound Region is that of Thomas
(38) "drought is a meterologic phenomenon that occurs during a period when
precipitation is less than the long-term average and when this deficiency is
great enough and continues long enough to hurt mankind."

The area may be affected by deficient precipitation for short
periods in any year or season. A table prepared for the region gives the
distribution of the total number of occurrences of consecutive days with less
than 0.1 inch of precipitation for durations of from 1 to 19 days and 20 or
more days. The total number of occurrences of 5 or more consecutive dry days
(less than 0.1 inch of precipitation) is uniform throughout the area. The
number of occurrences of 20 or more consecutive dry days however shows con-
siderable areal variation, ranging from 20 to 30 along the perimeter of the
Sound to ]k to 26 in interior parts of southern Connecticut. The chance of
an extended dry spell appears to be 15 to 50 percent greater along the coast
than in the hilly interior areas.

A widely used measure of drought severity and duration is the
Palmer Drought Index (24) . This index is based on the accumulated weighted
difference between actual precipitation and that required for the particular
time and place. Figure 6 is a plot of the monthly Palmer Drought Index for
the period 1929-72 and can be used to determine the length and severity of
both wet and dry periods in the region.

Figure 6 shows a total of 21 periods of drought lasting 3 or more
months. Droughts of severe or extreme intensity lasting a month or more occurred
7 times encompassing a period of 53 months. The first prolonged drought in
the period of record began in July 1929 and continued through August 1932; the
most extreme conditions were reached in September and October of 1930. The
longest and severest drought affecting the entire northeastern United States,
began in March I962 and continued through I967. This drought is classed as
severe or worse from August 1964 through February I967.

In addition to affecting plant life these lengthy droughts resulted
in reduced streamflow and lowered ground-water levels. The greatest impact
was felt during the growing season when both agriculture and water supply must
be satisfied by precipitation plus the water stored in reservoirs and the
ground. The effect of the 1960's drought on streamflow and ground-water
levels has been summarized by Barksdale and others (J_) and Cohen and others
(6). Figure 7 depicts the streamflow and antecedent ground-water conditions
in 1965 when the hydrologic effects of the drought were most severe.

16

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Barksdale and others (I966).

After

Drought conditions can end rapidly as illustrated by the events
of August 1955 in coastal Connecticut. This area had been experiencing a
moderate drought during July of 1955 but two August hurricanes resulted in
2.5 times the normal monthly precipitation. As a result the Palmer Drought
Index went from moderate drought to extreme wet spell values in a one month
interval .

4.0 FRESH SURFACE-WATER BODIES

Fresh surface-water bodies include approximately 75 streams of
various size that drain into Long Island Sound and numerous lakes and ponds.
All of the streams located on both shores of the Sound are tidal in their
lower reaches and are hydraul ical ly connected to adjacent ground-water reser-
voirs. Streamflow is derived from direct runoff of precipitation and ground-
water discharge both within and out of the Long Island Sound Region. Flow
characteristics of the streams vary depending on precipitation, on drainage
area, on basin characteristics such as geology, slope and the degree of
urbanizat ion,and on effects of man-made diversions.

k. 1 Avai labil ity of data

Measurements of streamflow have been made on many streams within
or adjacent to the Long Island Sound Region since the early 1900's. These
records have been published in U.S. Geological Survey Water-Supply Papers
and in the annual series entitled Water Resources Data for Connecticut, Part
1 {kV) , and Water Resources Data for New York, Part 1 (kl) . Flow records of
selected streams are published on a monthly basis in Water Resources Condi-
tions in Connecticut (43) and Water Resources Summary, Long Island (kk) .
Short-term forecasts of streamflow are published monthly by the National
Weather Service in Water Supply Outlook for the northeastern United States
(19).

Twelve continuous-record stream gaging stations in Connecticut
and one in New York having periods of record in water years 19^1-70 were used
as the primary surface-water data for the mainland part of the study area.
Four of these stations, located outside the region boundary, measure inflow
to the area. Ten continuous-record stations within the region have periods
of record for water years 1961-70. The records of five of these stations
were adjusted to the reference period 19^1-70, while the other five stations
were used for low-flow values only.

Forty-two low-flow partial -record sites, in and near the mainland
part of the region, at which discharge measurements were made in water years
1961-70 were selected to study the range and variability of low flows. The
values of the 7-day, 10-year recurrence interval low flow for these sites
were estimated through relation curves of discharge, with the long-term
records. Drainage areas of the low-flow partial -record sites range from 1
to 29 square miles but are generally between k and 15 square miles.

The primary surface-water data for Long Island consists of 19
continuous-record stream gaging stations having periods of record in water
years 19^0-65. Four of these stations are on streams that discharge into
Long Island Sound whereas the others drain south into the Atlantic Ocean or
into Great Peconic Bay. Surface drainage areas of these streams range from
k to 75 square miles.

The information on average annual, and.average monthly runoff
and the 7-day, 10-year low flows has been prepared in map format (see
Appendix C) . The streamflow information for the continuous record gaging
stations on the mainland is summarized in Appendix E.

4.2 Fresh water inflow to the Sound

The three principal streams flowing into Long Island Sound--the
Thames, Connecticut, and Housatonic Rivers — have a combined drainage area of
14,700 square miles, 91 percent of the 16,200 square mile mainland drainage
area. Annual runoff to the Sound averages 26,200 cubic feet per second (cfs) ^

1 - One cubic foot per second (cfs) is equivalent to 646,317 gallons per day
to approximately 0.65 million gallons per day (mgd), and to 0.24 billion
gallons a year (bgy) .

19

equivalent to 1.62 cfs per square mile or 6,200 billion gallons per year and
varies from 14,000 to 37,000 cfs as shown on Figure 8,

Figure 8. Estimated annual inflow to Long Island Sound 1929-70. The graph
indicates that one calendar year can bring almost three times as much fresh
water inflow as another.

Average annual runoff from the Thames River basin is 1 .64 cfs
per square mile. This is slightly greater than the rate of runoff from the
Connecticut and Housatonic River basins (1.62 and 1.61 cfs per squara mile,
respect i vej 1 y) . The distribution of average annual runoff in the maini'and
part of the region is shown on Figure 9.

Average monthly runoff to the Sound varies from 4.0 cfs per
square mile in April (65,100 cfs, or 1,250 billion gallons) to 0.6 cfs per
square mile in September (9, 800 cfs, or 190 billion gallons); monthly inflow
to the Sound has been as high as 139,000 cfs and as low as 4,300 cfs, in the
period of record beginning in 1928. The average monthly runoff for the cal-
endar year period 1941-70 is shown on Figure 10.

20

fpHK^^'

Figure 9. Average annual runoff on the north shore of Long Island Sound in
cubic feet per second per square mile, 19^1-70 water years.

70 000

60 000

50.000

40 000

30 000

20 000

10 000

JAN FEB MAR APR HAAY JUNE JULY AUG SEPT OCT MOV DEC

Figure 10. Estimated average monthly inflow to Long Island Sound 19^1-70.

21

The average inflow to the Sound in 7 consecutive days of a dry
weather period may be expected to go below 3^000 cfs (0.18 cfs per square
mile) once in ten years. Regulation of the three principal streams entering
the Sound holds the dry-weather inflow at a higher level than would occur
without regulation. The 7-day, 10-year annual minimum runoff from unregulated
tributaries in the mainland part of study area ranges from 0.01 to 0.05 cfs
per square mi le.

4.3 Coastal streams

The 66 mainland coastal streams flowing directly into the Sound,
other than the Thames, Connecticut and Housatonic Rivers, have a combined
drainage area of 1,467 square miles. The three largest are the Pawcatuck
River (304 square miles), the Q.uinnipiac River (166 square miles), and the
Saugatuck River (93.2 square miles). Drainage areas of the other coastal
streams vary from about 1 to 64 square miles, with most ranging from 3 to
30 square mi les.

The average annual runoff from a sample of mainland coastal streams
(mean drainage area less than 10 square miles) is 1.8 cfs per square mile;
the average monthly runoff varying from a high of 3.9 cfs per square mile in
March to a low of 0.5 cfs per square mile in August. The 7-day, 10-year
annual minimum runoff is estimated to be about 0.01 cfs per square mile,
which is probably close to the lowest 10-year runoff to be expected from the
mainland coastal streams.

An estimated 77 cfs (50 mgd) is discharged into the Sound from
coastal streams on Long Island. The four continuously gaged streams that
flow into the Sound (Glen Cove Creek, Mill Neck Creek, Cold Spring Brook and
the Nissequogue River) have surface drainage areas of 7 to 27 square miles
and average annual runoff of 4.6 to 42.1 cfs. In comparison with mainland
streams, the variation in annual and average monthly runoff is small. For
example, the average monthly flow of the Nissequogue River during the highest
average month (March) is 45.6 cfs, only 1.2 times greater than the lowest
average month (October) .

Under natural conditions 90 to 95 percent of Long Island stream-
flow consists of ground-water discharge and as a result the correlation be-
tween surface drainage areas and average flows is poor. In areas of urban
development, however, direct runoff constitutes a much higher percentage of
total discharge.

4.4 Annual maximum streamflows

The mean of the annual maximum discharges (the "mean annual flood")
for the continuous-record stations in and near the mainland part of study area
ranges from 10 cfs per square mile for a drainage area of 10,000 square miles
to about 50 cfs per square mile for a drainage area of 10 square miles. The
maximum discharge of the Connecticut River near Middletown (10,900 square mile
basin) was 267,000 cfs on March 12, 1936, while combined maximum discharge for
the seven largest rivers flowing to the Sound (gaged drainage area of 13,900
square miles) was more than 400,000 cfs in March 1936 and in August 1955.

22

TABLE 1, PRINCIPAL LAKES, PONDS AND RESERVOIRS

■ ion

Ashland Pond at Jewett City

Amos Lake at Preston

Aspinook Pond at Jewett City

Avery Pond near Preston

Babcock Pond near Westchester

Barnes Reservoir near Chesterfield

Beach Pond near Voluntown

Beachdale Pond at Voluntown

Billings Lake near Glasgo

Bogue Brook Reservoir near Chesterfield

Buddlngton Pond near Groton

Deep River Reservoir near Oilman

Dodge Pond at Niantic

Fairview Reservoir near Nor\vich(own

Fairy Lake near Chesterfield

Fitchville Pond at FitchviHe

Gardner Lake near Fitchville

Glasgo Pond at Glasgo

Groton Reservoir near Groton

Hog Pond near Hamburg

Hopevi I le Pond at Hopevi I 1e

Lake Konomoc near Chesterfield

Lake of Isles near Shewville

Lantern Hill Pond near Shewv I I le

Ledyard Reservoir near Groton

Long Pond near North Stonington

Hystic (Dean) Reservoir near Mystic

Mystic (Palnver) Reservoir near Mystic

Norwich Pond near Hamburg

Oxoboxo Lake near Hontville

Pachaug Pond at Pachaug

Paper Mill Pond at Versailles Station

Pataguanset Lake at East Lyme

Pickerel Pood near Moodus

Poheqnut Reservoir near Groton

Powers Lake near East Lyme

Rogers Lake at Laysville

Smith Lake near Groton

Stony Brook Reservoir near Oakdale

Taftville Pond at Taftvi Me

Taftville Reservoir at Taftville

WaWog Pond near Glasgo

Strait
Wallingford

llle

102
105
333

1*6. 1
11.7

ue..s

105
72

69.2
U87

\eu

115

69
1 1*9
225
87.1
15.1

95
98.6
12.5
23.9

27.5
\i>U
831

153
265

Cedar Lake near Chester

68

Deep Hollow Reservoir

2i.9

Deuces Pond near Chester

3.*.

HaniT«nasset Reservoir near North Madison

377

Kelseytown Reservoir near Killlngworth

15.'.

Killingworth Reservoir near Killingworlh

Pataconk Reservoir near Chester

S5.5

Turkey Hill Reservoir near West Haddam

80.1*

Upper Pond near Tylerville

6.2

Uaterhouse Pond near Chester

1.7.1

Bradley and Hubbard Reservoir

Branford Supply Ponds near Branford

Cedar Pond near North Branford

CI arks Pond at Mt . Carmel

Clear Lake near North Branford

Community Lake at Wallingford

Foster Lake near Meriden

Glen 0am Reservoir near Woodbridge

Hanover Pond at Meriden

Indian Lake at Orange

Konolds Pond near Woodbridge

Lake Bethany near Bethany

Lake Chamberlain near Bethany

Lake Oawson near Woodbridge

Lake Gail lard near Branford

Lake Quonnipaug at North Guilford

Lake Sal Constat I at East Haven

Lake Watrous near Bethany

Lake Whitney at New Haven

Lake Wintergreen at Woodbridge

Lane Pond Reservoir near North Branford

Lidyhites Pond near North Branford

Linsley Pond near North Branford

Maltby Lakes near West Haven

MenuncaCuck Reservoir at North Guilford

Merimere Reservoir near Meriden

New Naugatuck Reservoir nea

North Farms Reservoi

Phipps Lake Reservoi

Pine River (McKenzie) Reservoir near

Wall ingford
Pistapaug Pond near Ourham
Silver Lake near Meriden

Spring Brook Reservoir near East Wallingford
West Lake near North Branford

Aspetuck Reservoir near Easton
Beaver 0am Lake near Nichols
Bunnel Is Pond near Bridgeport
Easton Reservoir near Easton
Hemlock Reservoir near Plattsville
Lake Forest near Bridgeport
Peat Swamp Reservoir near Ansonia
Samp Ftortar Reservoir near Fairfield
Trap Falls Reservoir near Huntington

25
30
72
36
83

390
106
200

Grupes

Reserve

r near New Cana

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John 1

. Milne 1

ake near New Ca

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Laure

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New Ce

naan Reservoir near New

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North

Stamford

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Putnai

Lake near Round Hill

Rockwood Lake r

ear Round Hill

Saugstuck Rese

voir near Lyons

Plain

Streets (Popes

Pond at North

Wilton

61

58.lt

l<2

lies

7!

82.6
50
3Wi

2Z

71
265
320

96
96

Maximum

depth

Total storage

Usable sto

(ft)

(million qallonO

(million ,al

17

200

200

M

655

65

27

9k2

800

lit

101

None

8

134

I31t

25

170

170

65

2,633

1 , 290

10

lt2.2

35.9

a

lt69

205

25

212

212

20

20

35

3811

381t

51

227

None

30

1150

ItSO

60

235

235

20

lito

IttO

it3

2,177

1,055

26

395

350

12

256

256

.-

502

502

16

225

225

60

672

672

10

172

100

typ«

38
37

206

1,077

1,61.0

126

'.97

175

223

l*i*2

1,71.0

1*36

500

331

l.itOO
18.9

187

11*9

50
153

506
63

66

1.15

1''7

5,61.8

3,801

31.2

537

177

2,1.61.

610
2,253
2,1*50

500

1 1,921.

2t«0

1.76
21.5

206
613

1,640

105
175
223
Mt2
1,71.0
1.36
500
331

1,080
18.9

197
ll»9

603
891.
209

6,1.05
U91.

1,500
709
258
100
50

260
197

225

650

66

1.15
11.7

56

610

2,253

2.250
116
512
572
1*68
11 , 92i«
2ltO

Not used
Recreation
Not used
Recreation

Do.
Publ ic water supply
Recreation

Do.

Do.
Publ Ic water supply

Do.

Do.
Scientific InvestlgatI
Public Mater supply

Do.
Recreation

Do.

Do.
Public water supply
Recreation

Do.
Publ ic water supply

tion

Do.

Publi
Recre
Publ i

Industrial
Publ ic wate
Recreation

■ supply
r supply

supply

supply

supply

Do.
Do.

Do.
Recreation
Publ ic water supply

Do.

Public water supply
Recreation

Do.

Do.

Do.
Industrial
Recreation
Public water supply
Recreation

Do.

Do

Do.
Recreation
Public water supply

Do.

Do.

Do.

Do.
Recreation

Do.
Publ ic water supply

Do.

Do.

Do.
Recreation

Do.

Recreation

Public water supply

Recreation

Public water supply
Recreation

Do.
Public water supply

Do.

Do.

Do.
Recreation
Public water supply

Public water supply

23

k.5 Lakes and ponds

There are hundreds of lakes and ponds of various size mostly
located in the Connecticut part of the Long Island Sound Region. The larger
lakes are generally man made and are used for water supply, flood control
and recreation. Table 1 lists pertinent data on the major lakes and ponds
in Connecticut.

5.0 GROUND WATER

5. 1 Availability of hydrogeologic data

Hydrogeologic information for the Long Island Sound Region is
contained in numerous basic data and interpretive reports. Most interpretive
studies published prior to I960 are qualitative and cover relatively small
parts of the region. Recent comprehensive reports include the series of
Water Resources Bulletins prepared by the U.S. Geological Survey in coopera-
tion with the State of Connecticut {ZJj 36, JTj 3_L) ; New York Water Resources
Commission Bulletins {5j 8) and several U.S. Geological Survey Water-Supply
and Professional Papers prepared in cooperation with New York State and
county agencies (6^ 10, 25, 26, 3^) .

Water-level and ground-water quality data from wells within the
study region are published each year in Water Resources Data for Connecticut,
Parts 2 and 3 (^ ; and Water Resources Data for New York, Part 2 {kT) .
Water levels are also published on a monthly basis in Water Resources Condi-
tions in Connecticut (43) and Water Resources Summary, Long Island (kk) .

The existing information on ground-water availability and quality
necessary for planning has been updated and presented in map format for this
study (see Appendix C) . In some aspects of plan formulation it may be nec-
essary to refer to information contained in the selected references listed in
Appendix A.

5.2 The hydrogeologic system of Long Island

Two recent reports (5^ 1 0) have summarized the pertinent existing
information on Long Island's hydrologic system and are the basis of this
section. Although Long Island is generally considered as a single hydrologic
unit it can be divided into subareas for purposes of analysis. Subareas
referred to in the text and on tables are shown on Figure 11.

The most important hydrologic feature of Long Island is the fresh
ground-water reservoir beneath its surface. The boundaries of this reservoir
are (1) the water table (2) the fresh-salt water interfaces (3) the bedrock
surface and (4) the streams. The geologic framework of the ground-water
reservoir consists of a thick wedge-shaped mass of saturated sand, gravel,
silt and clay as shown on Figure 12.

2k

Ground-water divide;
September 1965 water levels

Southern part of
water-budget area

Grett'

rM'"~^^i-'-'^outhern

nearshore area

Water-budget area

5 0 5 10 15 20 25 MILES

ll Ml I I \ I I I

_L

_1_

Figure 11. Hydrologic areas and subareas on Long Island. After Franke and
McClymonds (1972, Fig. 2) .

NORTH

SOUTH

ATLANTIC
OCEAN

Clay Sandy clay, clayey

Gravel

Not to scale

Figure 12. Section illustrating the geologic features of the ground-water
reservoirs beneath Long Island. After Franke and McClymonds (1972, Fig. 8).

25

TABLE 2. ESTIMATED VOLUME OF FRESH GROUND WATER BENEATH PARTS OF LONG ISLAND

Volume designation

Volume of
deposits satu-
rated with
fresh ground
water (cubic
mi les)

Total volume

of fresh
ground water

Range in estimated
storage capacity

(trillions of gallons)

Item (1) (2)

(a) Above sea level in

water-budget area 5

(b) Beneath entire water-

budget area 180

(c) Beneath area adja-

cent to water-
budget area' 100

(d) Sums of Items b and c

(rounded) 280

(e) Beneath mainland

Kings and Queens

Counties 10

(f) Sums of items d and e

(rounded) 290

(3)

W

1.6
59

33
92

3.3

95

0.28- 0.56
10 -20

5.5 -11

15 -31

.55- 1.1

16 -32

1 Includes volume beneath the nearshore areas and the adjacent bays.

Adapted from Franke and McClymonds (1972)

Fresh ground water occurs from the bedrock surface to the water
table except in the Forks and islands of eastern Long Island. The estimated
quantities of fresh water stored beneath various parts of Long Island are
listed on Table 2. Only a part of the fresh water beneath Long Island is
available for use by man and the amount that can be recovered depends upon
the water management scheme.

The water table and fresh-salt water interfaces are not station-
ary boundaries and their position depends on the balance between inflow
(recharge) to and outflow (discharge) from the ground-water reservoir. A
map prepared for this study (see Appendix C) shows the position of the upper
boundary, the water table, as of March 1971. The position of the fresh-salt
water interface generally lies seaward of the shore but has been accurately
determined only in southwestern Nassau and Southeastern Queens Counties.

Recharge to the ground-water reservoir under natural conditions
is derived solely from precipitation. In the 760 square mile "water budget
area" it is estimated that the average annual recharge from precipitation
is approximately 820 million gallons per day (5). Most recharge takes place
during the period October to March when vegetation is generally dormant.

The ground-water reservoir contains six major hydrogeologic units
whose properties affect the storage and movement of water. Maps showing the
known extent, thickness, depth to and hydraulic properties of these units
were prepared or modified for this study by the U.S. Geological Survey (see
Appendix C) . Such maps in conjunction with continuing programs will enable

26

predictions of the quantity of water that can be withdrawn from the ground-
water reservoir at a given site and the hydrologic response to man-made or
natural changes. A summary of information on the major hydrogeologic units
is shown on Table 3.

There are two general systems of circulation within the ground-
water reservoir. A shallow circulating subsystem, generally under water-table
conditions, that discharges principally into streams and a deep circulation
subsystem, generally under artesian conditions, that discharges into the bays,
the Atlantic Ocean and Long Island Sound. Seepage to springs and ground-water
evapotranspi ration are the other principal means of natural discharge from
the ground-water reservoir. The pattern of ground-water circulation under
natural conditions is shown on Figure 2.

A water budget analysis quantitatively expresses the inflow to,
outflow from and changes in storage within a hydrologic system. Table k is
a water budget for approximately half of Long Island (refer to Fig. 11) pre-
pared by Franke and McClymonds (J_0) . This table is an approximate summary of
relations between the components of the hydrologic system under natural condi-
tions.

Fresh ground water on Long Island, under natural conditions, has
a dissolved solids content of less than 50 mg/1 (milligrams per liter) and
IS of excellent chemical quality for most uses. The low dissolved solids
concentration is due to the generally low solubility of materials in the
saturated zone. The pH is generally low (commonly less than 6) which makes
the water corrosive to metals and in places the iron content is considerably
above the 0.3 mg/1 limit recommended for public supply use (^5) .

The ground-water quality in the upper glacial, Magothy and Lloyd
hydrogeologic units has been summarized on maps by the U.S. Geological Sur-
vey (see Appendix C) . The chemical and physical quality of water at any
point within the ground-water reservoir results from the natural geochemical
conditions and the effects of man's activities.

The average natural ground-water temperature varies from about
50° to 70°F (10-21°C) depending on depth below land surface. The average tem-
perature to a depth of about UOO feet is relatively constant and thereafter
increases at a rate of about 1°F per hundred feet of depth (5). Seasonal
variation in ground-water temperatures in the upper part of the saturated
zone ranges from 2° to 20°F. The range in seasonal variation decreases with
depth.

Man's activities have to various degrees affected the natural
hydrologic system by depleting the ground-water reservoir, artifically recharg-
ing the ground-water reservoir and changing the ground-water quality. The
ground-water reservoir is depleted by (1) irrigation (2) increased direct
runoff to streams from urbanized areas (3) disposal of sewage effluent to the
ocean and (h) export of water to New York City. The total loss is estimated
at 125 mgd in 1965^ 60 percent of which (75 mgd) is discharge of sewage
effluent to the ocean (10) .

27

TABLE 3. MAJOR HYDROGEOLOGI C UNITS OF THE GROUND-WATER RESERVOIR

ON LONG ISLAND, NEW YORK

Geologic unit

Upper Pleistocene
depos i ts

Hydrogeo!ogic
uni t

Upper glacial

aqu ifer

Approximate maximum
thickness (feet)

600

Depth from land sur-
face to top (feet)

0-50

Gardiners Clay

Gardlners Clay

300

50-^00

Jameco Gravel

Jameco aquifer

300

100-550

Hatawan-Group
Magothy Formation
undifferentiated

Magothy aquifer

1,100

0-600

Clay Mem-
ber

Rar i tan

Forma-
Tion

Lloyd Sand
Member

Rar i tan clay

Lloyd aquifer

300

500

0-1,500

200-1,800

Adapted from Franke and McClymonds (1972) and Jensen and Soren (in press)

j_/ Hydraulic conductivity denotes how readily water can move through porous material.

0-2,700

28

TABLE 3. MAJOR HYDROGEOLOGI C UNITS OF THE GROUND-WATER RESERVOIR
ON LONG ISLAND, NEW YORK— Continued

Physical characteristics of deposits

Water-bearing properties

Till (mostly along north shore and in moraines) composed of
clay, sand, gravel, and boulders. Outwash deposits (mostly
between and south of terminal moraines, but also interlayered
with till) consist of sand, fine to very coarse, and gravel.
Glaciolacustr ine deposits (mostly in central and eastern Long
Island) and marine clay (locally along south shore) consist of
silt, clay, and some sand and gravel layers; includes "20-foot
clay" In southern Nassau County and Queens County.

Clay, silt, and few layers of sand and gravel. Altitude of
top generally is 50-80 ft below mean sea level. Occurs in
Kings and Queens Counties, southern Nassau County, and
Suffolk County; similar clay occurs in buried valleys near
north shore.

Sand, fine to very coarse, and gravel; few layers of clay
and silt. Occurs in Kings and Queens Counties, and southern
Nassau County; similar deposits occur in buried valleys near
north shore.

Sand, fine to medium, clayey in part; interbedded with lenses
and layers of coarse sand and sandy and solid clay. Gravel
is common in basal 50-200 ft.

Clay, solid and silty; few lenses and layers of sand; little
gravel .

Sand, fine to coarse, and gravel, commonly with clayey matrix;
some lenses and layers of solid and silty clay.

Crystalline metamorphic and igneous rocks. A soft clayey zone
of weathered bedrock locally is more than 100 ft thick.

Till has low hydraulic conductivity; I'commonly causes perched-
water bodies and impedes downward percolation of water to under-
lying beds. Outwash deposits have moderate to high hydraulic
conductivity; specific capacities of wells tapping them range
from about 10 to more than 200 gpm per foot of drawdown. Good
to excellent infiltration characteristics. G 1 ac iol acustr ine
and marine clay deposits have mostly poor hydraulic conduct ivi tie
but locally have thin layers of sand and gravel with moderate
hydraulic conductivities; generally retard downward percolation
of ground water. Contains fresh water, except near shorelines.
Till and marine deposits locally retard salt-water encroachment.

Poor hydraulic conductivity; constitutes confining layer for
underlying Jameco aquifer. Locally, sand layers yield small
quantities of water.

Moderate to high hydraulic conductivity; contains mostly fresh
water, but brackish water and water with high iron content
locally in southeastern Nassau County and southern Queens County.
Specific capacities of wells in the Jameco range from about 20 to
150 gpm per foot of d rawdown .

Most layers have poor
high hydraulic conduct
in the Magothy general
drawdown, rarely are a
in uppermost parts, el
excellent quality but
south shores. Constlti
in western Long Island
Has been invaded by sa
County and southern Qu
shore.

to moderate hydraulic conductivity; some have
"vity locally. Specific capacities of wells
ly range from I to about 30 gpm per foot of
IS much as 80 gpm per ft. Water Is unconfined
sewhere is confined. Water is generally of
has high iron content locally along north and
utes principal aquifef for public-supply wells
, except Kings County where it is mostly absent.
.Ity-ground water locally In southwestern Nassau
leens County, and in small areas along north

Poor to very poor hydraulic conductivity; constitutes confining
layer for underlying Lloyd aquifer. Very few wells produce appre-
ciable water from these deposits.

Poor to moderate hydraulic conductivity. Specific capacities of
wells in the Lloyd generally range from I to about 25 gpm per foot
of drawdown, rarely are as much as 50 gpm per ft. Water is confined
under artesian pressure by overlying Raritan clay; generally of
excellent quality but has high Iron content locally. Has been
invaded by salty ground water locally in necks near north shore,
where aquifer is mostly shallow and overlying clay discontinuous.
Called deep confined aquifer in some earlier reports.

Hydraulic conductivity poor to virtually zero; constitutes virtually
the lower boundary of ground-water reservoir. Some hard, fresh
water is contained In joints and fractures, but is impracticable to
develop at most places; however, a few wells near the western edge
of Queens and Kings Counties obtain water from the bedrock.

29

TABLE k. WATER BUDGETS OF THE NORTHERN AND SOUTHERN PARTS OF THE
"WATER BUDGET AREA" OF LONG ISLAND, WATER YEARS 19^0-65

[In millions of gallons per day]

Type of water-
budget element

No.

Water-budget element

Water-budget area

Northern

Southern

Entire

part

part

Inflow

1

Precipitation -

660

950

1,600

Internal dis-

2

Direct runoff

5

15

20

tribution.

3

Ground-water recharge J. .

320

465

785

4

Ground-water discharge
to streams.'

45

275

320

Outflow...

5

Evapotranspiration of
precipitation .<

325

470

795

6

Subsurface outflow of
ground water.

270

180

450

7

Streamflow discharging to
salt water.

50

290

340

8

Evapotranspiration of
ground water.'

5

10

15

' The quantities in this table were derived with the assumption that no significant
change in ground-water storage occurred in the water-budget area during the period,
water years 1940-66. Independent quantitative estimates were made for all compon-
ents in the table unless otherwise noted. None of the values in this table are accurate
to more than 2 significant figures, and many values are accurate to less.

Where more than 2 significant figures are shown, the entry was derived
from other entries in the table, and an additional significant figure was retained to
balance inflow and outflow. (See footnotes below.)

2 The estimate of ground-water recharge was obtained by adding components 4, 6,
and 8.

» The estimate of ground-water discharge to streams was obtained by subtracting
component 2 from component 7.

* The estimate of evapotranspiration of precipitation was obtained by adding
components 6, 7, and 8 and subtracting the total from component 1. Therefore, the
subtotal of components 5, 6, 7, and 8 (total outflow) equals component 1 (total inflow) .

• These values may be in error by as much as 100 percent or more. Values are in-
cluded mainly to indicate order of magnitude.

After Franks and McClymonds (1972)

Artificial recharge to the ground-water reservoir is from cess-
pools, septic tanks, recharge basins, injection wells and leaky water and
sewer pipes. The total artificial recharge in Nassau and Suffolk Counties
is estimated at 310 mgd in 1965; approximately 68 percent (210 mgd) of which
is from cesspools, septic tanks and recharge basins (10) .

The quality of ground water has been affected primarily by waste
disposal practices that include disposal of sewage and industrial wastes
into the ground through septic tanks, cesspools and recharge basins. Dete-
rioration of quality has also resulted from the injection of heated water
through recharge wells, the discharge of smoke and other particulate matter
into the atmosphere, the leaching of fertilizers and salt-water encroachment
in areas of overdevelopment.

Cohen and others (5) outlined the progressive pattern of ground-
water development in Long Island in three stages:

30

Individually owned shallow wells used for water supply and cess-
pools used for domestic waste disposal.

Public supply wells that tap the deeper artesian hydrogeologic
units and use of cesspools for domestic waste disposal.

Deep public supply wells and large scale communal sewage collec-
tion and disposal systems.

It is the third stage of development that has a significant
impact. The effect of sewering and subsequent discharge to the ocean dis-
rupted the hydrologic balance resulting in large scale salt water encroach-
ment and lowered water levels in areas of large-scale pumping (the status of
water development in Long Island as of 1966 is shown on Fig. 13).

j_

EXPLANATION

SUBAREA CHARACTERISTICS

A Hydrologic system mainly is in a state of virtual quantitative equilibrium.
B Transitional in development between subareas A and C.
C Hydrologic system is locally out of balance; local salt-water intrusion.
D Hydrologic system is out of balance: widespread salt-water intrusion.

E Hydrologic system is out of balance; may be subject to salt-water intrusion in the future.
F Ground-water development is negligible, and the hydrologic system is in balance.
G Large parts of the subarea are contaminated with salty ground water owing to
former intensive ground-water development and related salt-water intrusion.

Figure 13. Status of water development in 1966,
(1966, Fig. 8).

After Heath and others

31

Recent hydrologic appraisals {S, 10) have emphasized that future
water management must take into account the balance of the Long Island
ground-water reservoir as expressed by the equation: Inflow = Outflow ±
changes in storage and have outlined several management alternatives and
their consequences. As of I968, the total fresh-water outflow from the
ground-water reservoir beneath the water budget area was greater than the
inf lowland the amount of fresh ground water in storage was declining. If
present management practices continue it is likely that within the water
budget area (1) the hydrologic imbalance will increase, (2) ground-water
levels will continue to decline, and (3) salty ground water will continue to
move slowly inland. The yield of the Long Island ground-water system is not
a single fixed number but will vary depending on hydrogeologic conditions,
the management scheme, and the extent to which certain undesirable effects of
development will be tolerated.

A continuous program of hydrologic investigations is essential
to provide the information necessary for water management and planning. Pre-
sent activities that provide a continuous record of the hydrologic system
should be continued and further refined. More intensive study and monitor-
ing of water quality are required in various parts of the island and continu-
ing efforts should be made to define the shape and areal extent of the hydro-
geologic units particularly in eastern Suffolk County.

5.3 The hydrogeologic system on the north shore of Long Island Sound

The hydrogeologic information in the subregions of the Long
Island Sound Regional Study Area that lie north of the Sound varies in
quantity and quality. The most complete information is presently available
for Subregions 1, 4 and 5. On-going studies by the U.S. Geological Survey
are in various stages of completion in Subregions 2 and 3 whereas the part
of Subregion 6 in this area is deficient in data.

The principal hydrologic unit on the north shore of the Sound is
the river basin drained by a perennial stream. The saturated zone beneath
each of these basins constitutes a fresh ground-water reservoir, the boundaries
of which are (1) the topographic drainage divides (2) the water table (3) the
streams and (k) impermeable bedrock. For small areas that border the coast
and are not drained by a stream the interface between fresh and salty ground
water is a boundary. The geologic framework of the ground-water reservoirs
on Figure ]k includes the upper fractured part of the bedrock and unconsoli-
dated layered and unlayered deposits of sand, gravel, silt, clay (termed
stratified drift and till respectively).

Recharge to each ground-water reservoir under natural conditions
is derived solely from precipitation on the drainage basin. The amount and
rate of recharge varies from basin to basin and with time. In areas where
the surface materials are principally till and bedrock the estimated average
annual recharge is approximately 0.3 mgd/mi (million gallons per day per
square mile) and in areas covered by stratified drift it is approximately 1
mgd/mi^. Most recharge occurs during the period October through March of
each year when vegetation is generally dormant.

32

WATER

table:

EXPLANATION

STRATIFIED DRIFT

Till

SAND AND GRAVEL

SAND. SILT AND CLAY

SAND

>2

HETEROGENEOUS COMPACT CRYSTALLINE BEDROCK

MIXTURE or SAND. GRAVEL.
SILT AND CLAY SIZED
MATERIAL

Figure 14. Block diagram illustrating the general geologic features of a
ground-water reservoir on the north shore of Long Island Sound. Adapted
from Cervione and others (1972, Fig. 32).

The ground-water reservoirs contain at least two and generally
three major hydrogeologic units whose properties affect the storage and
movement of water. Maps showing the known extent, thickness and hydraulic
properties of the most important unit, stratified drift are available for
parts of Subregions 1, 4 and 5 in the references cited in the introduction
to this section. The important characteristics of all three hydrogeologic
units is summarized on Table 5.

33

TABLE 5. MAJOR HYDROGEOLOG I C UNITS OF THE GROUND-WATER
RESERVOIRS ON THE NORTH SHORE OF LONG ISLAND SOUND

Geologic unit
Pleistocene deposits

Hydrogeologic unit

Stratif ied-drtft
aqui fer

Triassic sedimentary
bedrock

Crystalline bedrock

Sedimentary-bedrock .
aqui fer

Crystal 1 ine-bedrock
aqui fer

Physical characteristics of deposits

Unconsolidated sediments composed of inter-
bedded layers of gravel, sand, silt and
clay. Sites of former glacial lakes contain
predominantly very fine sand, silt and clay.
Deposits occur principally in valley areas.
Maximum known thickness is approximately 300
ft.

Unconsolidated nonstratif ied sediment com-
posed of various proportions of sand, gravel,
silt and clay. D i scent inuous ly mantles bed-
rock and is overlain in valley areas by
stratified drift. Generally less than 10 ft
thick but maximum known thickness exceeds
150 ft.

Consol idated sandstones, shales and conglom-
erates interbedded with basalt (traprock).
Underlies part of Subregion 3.

Consolidated crystalline metamorphic and
igneous rocks. A soft zone of weathered
bedrock locally is more than 100 ft thick.

Water-bearir.g properties

Most saturated stratified drift has moderate
to high hydraulic conductivities.!^ Lacus- '
trine deposits of very fine sand, silt and
clay, however, have low hydraulic conductiv-
ity. Major water-bearing unit in the area
capable of yielding from 50 to over 2000
gpm (gallons per minute) to properly construct-
ed individual wells. Estimated long-term
yields of selected stratif ied-drift aquifers
in Subregions 1, k and 5 range from less than
0.5 to over 15 million gallons per day.

Till has low hydraulic conductivity and is
generally thin. Shallow wells tapping till
formerly used for domestic supply but most
proved inadequate for modern demands and
were replaced by drilled wells tapping bedrock.

Hydraulic conductivity unknown. Contains

water-bearing fractures and pores in at least
the upper several hundred feet. Water quality
locally poor. Yields of wells tapping this
aquifer range from less than 1 to 305 gpm.
The median yield is approximately 11 gpm and
the median specific capacity is approximately
1.3 gpm per foot of drawdown.

Hydraulic conductivity unknown. Contains
water-bearing fractures in at least the upper
300 ft. Yields of wells range from less than
1 to 200 gpm but yields greater than 20 gpm
are rare. The median yield is approximately
7 gpm.

]_/ Hydraulic conductivity denotes how readily water can move through porous material.

in order to assess ground-water availability at any given location
the major hydrogeologic units have been subdivided or combined according to
their ability to yield similar amounts of water to wells. Maps prepared by
the U.S. Geological Survey for Subregions 1 through 5 delineate the areas capa-
ble of yielding selected amounts of water to individual wells (see Appendix C) .

Circulation within each ground-water res
shallow. Most ground water moves through the upper
zone and discharges principally to streams. A deep
may be present in the part of Subregion 3 containing
rocks. Ground-water evapotranspi rat ion and subsurfa
Sound are the other means of natural discharge from
The amount of subsurface outflow has been estimated
gallons per year) per mile of coastline in Subregion
tern of ground-water circulation under natural condi
3.

ervoir is relatively

300 feet of the saturated

circulation subsystem

saturated sedimentary
ce outflow to Long Island
the ground-water reservoirs.
to be 100 mgy (million

1 (37) . The general pat-
tions is shown on Figure

Fresh ground water under natural conditions is generally of
excellent chemical quality for most uses. Dissolved solids are less than
500 mg/1 with the exception of some ground water in the sedimentary rocks of

3^

Subregion 3. Iron and manganese concentrations commonly exceed the recom-
mended limit for public supply use of 0.3 mg/1 and 0.05 mg/1 respectively
(kS) . Approximately ^0 percent of the wells tapping stratified drift and
crystalline bedrock, sampled by the U.S. Geological Survey, had excessive
concentrations of iron and/or manganese. Hard to very hard ground water
(hardness as CaCOn, greater than 120 mg/1) is common in the sedimentary
rocks of Subregion 3 and in parts of Subregions 5 and 6 underlain by bedrock
or unconsolidated materials composed of calcium and magnesium carbonate. The
distribution of dissolved solids, iron and manganese and hardness of ground
water and of streams under conditions of low flow have been summarized on
maps for this part of the study region (see Appendix C) .

Other natural chemical constituents that are locally present in
concentrations exceeding U.S. Public Health Service (kS) or Connecticut
State Department of Health (7) recommended limits for drinking water include
sodium, fluoride, chloride and sulfate. Most of the reported excess concen-
trations of these constituents are from wells tapping the sedimentary bedrock
in Subregion 3.

In the Connecticut part of the study region, ground water pH is
generally between 6 and 8 although values as low as h.k and as high as S.k
have been measured. The average ground-water temperature is approximately
50°F and at depths greater than 30 feet fluctuates slightly. Ground water at
depths of less than 30 feet however may seasonally vary in temperature by as
much as 20° F (27).

The effect of man's activities on the hydrologic system, while
qualitatively similar to Long Island, are quantitatively different. Hydrolog-
ic imbalances resulting from overpumping or impairment of ground-water quality
are confined to within the area of a drainage basin. In addi t ion, only a
small part of the total water used on the north shore of Long Island Sound
is derived from the ground-water reservoirs. For example, in the lower Thames
River basin and in southwestern Connecticut approximately 5 to 10 percent of
the water used in the mid-1960's was from wells (37> 31) .

The two principal activities that result in losses of water from
the ground-water reservoirs are (1) disposal of waste water originally derived
from wells to streams or the ocean and (2) increased direct runoff to streams
in urbanized areas. This loss is greatest in the urbanized coastal areas,
but no quantitative estimate of its magnitude has been made.

Artificial recharge to the ground-water reservoirs is from septic
tanks, leaky water and sewer pipes and from streams and lakes adjacent to
centers of ground-water development. Artificial recharge from streams and
lakes is a very important factor in sustaining well yields. Most large pub-
lic and industrial supply wells tap stratified drift that is hydraul ical ly
connected to an adjacent stream. The effects of pumping induce the surface
water to move through the streambed material s and into the ground-water
reservoir.

35

The quality of ground water has been locally altered by (1) dis-
posal to the ground of sewage and industrial effluent and landfill disposal
of solid wastes, (2) leaching of fertilizers and deicing compounds, and (3)
induced recharge of water from streams and salt-water encroachment in areas
of ground-water development. Most cases of pollution are apparently local,
but there is no continuing program of monitoring ground-water quality to
evaluate long-term changes.

The existing pattern of development on the north shore of Long
Island Sound consists of:

(1) Surface-water reservoirs and well fields tapping stratified-
drift deposits that provide water for urbanized areas. Waste disposal is
principally by sewage treatment plants that discharge to streams, estuaries
and the ocean.

(2) Individual wells principally tapping bedrock provide water
for rural and many suburban parts of the area. Waste disposal is to septic
tanks and cesspools.

Both of the above patterns of development may produce hydrologic
problems. Large scale ground-water development reduces streamflow in adjacent
streams and by lowering the water table can affect lake levels and swamps.
During periods of low streamflow, the pumping may even dry up a reach of stream.
In the coastal urban centers of New Haven and Bridgeport, Connecticut pumping
over a long period resulted in widespread salt-water encroachment of the
strat if ied-dr if t aquifers and subsequent abandonment of many wells. In the
less developed areas, septic tank disposal may be inadequate and require sewer-
ing or the effluent may deteriorate the ground-water quality.

The development and management of ground-water resources must
take into account the hydrologic balance between inflow and outflow within
each ground-water reservoir. Only small local imbalances exist at the present,
primarily because of the small amount of development.

Future large scale ground-water development will occur principal-
ly in valleys containing thick permeable deposits of stratified drift. In
most areas, these deposits are hydraul ical ly connected to adjacent streams
and may be termed stream-aquifer systems. The sustained yield of these stream-
aquifer systems may vary considerably depending on the scheme of management.
For example, estimated yields of several stream-aquifer systems in Subregions
1, 4 and 5 shown on maps prepared for this study (see Appendix C) range from
less than 0.5 to over 15 million gallons per day. These yields were predica-
ted on a management scheme, the essential elements of which are (1) the water
pumped is not returned to the ground-water reservoir or stream near the site
of withdrawal, (2) minimal effect on streamflow, and (3) fairly constant rate
of pumping. Several alternative management schemes would significantly alter
the estimated long-term yields.

A continuous program of hydrogeologic investigations is necessary for
planning the optimal development and management of both ground- and surface-
water resources on the north shore of Long Island Sound. Such a program should

36

Include (1) expanded data collection activities particularly in areas of poten-
tial development and existing centers of ground-water pumpage, (2) monitoring
of ground-water quality to evaluate long-term changes due to man's activities,
(3) determination of the hydraulic properties of stratified drift and sedi-
mentary bedrock aquifers, (4) definition of the geometry and pattern of ground-
water circulation In the sedimentary bedrock of Subregion 3.

6.0 BRACKISH AND SALT WATER BODIES

Salty and brackish waters occupy Long Island Sound, the lower
reaches of the streams that drain into the Sound and the coastal and offshore
parts of the ground-water reservoirs. This section is concerned with the
Sound and saline parts of the estuaries because little is known about the
movement of salty ground water in the region. Some geographic features of
the Sound such as area and volume have already been noted on pages 5 and 6,
and detailed information on the configuration and depth is shown on hydro-
graphic charts and bathymetric maps (2J_, kO) published by the National Ocean
Survey. Figure 15 shows several geographic features of the Sound and the
principal estuaries referred to in this report.

Figure 15. Geographic features of Long Island Sound.

37

6. 1 Avai labi 1 i ty of Data

Measurements of tides and tidal currents have been made in
various parts of Long Island Sound and adjacent estuaries for at least 136
years (33) . The National Ocean Survey (formerly the U.S. Coast and Geo-
detic Survey) publishes tide tables of daily tide predictions and tidal
current tables on an annual basis (22, 23) . This agency also periodically
publishes hydrographic charts and bathymetric contour maps of Long Island
Sound (21 , kO) . Information on water movement as well as other aspects of
physical oceanography in the Sound and estuaries is contained in numerous
publications of Oceanographic institutions and scientific journals, many of
which are cited in the list of references.

6.2 Circulation and movement

The circulation or movement of water within Long Island Sound
and the adjacent estuarine streams is controlled by tides, fresh-water in-
flow, winds and other weather conditions, bottom topography and salinity or
temperature gradients. The circulation pattern in turn affects the chemical
composition of water and sediment distribution within the Sound and estuaries,

72° 00'

Figure 16. Tidal currents at the eastern end of Long Island Sound two hours
after "slack water" at The Race. Speed of currents in knots at time of
spring tides.

38

I

Long Island Sound is technically described as a co-oscillating
tidal basin (33) characterized by minimum tidal range and maximum tidal cur-
rent at its mouth and maximum tidal range and minimal tidal currents at the
almost closed western end. At the eastern passage known as The Race the
tidal range is 2.5 feet and the maximum currents are over 5 knots (5.8 mph) .
The tide range increases to the west, whereas the current velocities decrease.

The dominant horizontal motion of the waters of the Sound are the
semidiurnal tidal currents. The direction and speed of tidal currents in the
upper waters at the time of full moon and under normal weather conditions are
shown on tidal current charts prepared by the National Ocean Survey (22) . An
example of tidal surface currents at the eastern end of the Sound is shown on
Figure 16. While the tidal circulation pattern of the surface and near sur-
face waters is well defined relatively little is known about the deep current
circulation.

Tidal currents shown on such charts are subject to modification
by nontidal currents due to winds and fresh water inflow from rivers. For
example offshore and onshore winds modify the currents along the coast and
during periods of very high runoff the fresh water inflow from the Connecticut
River creates a distinct plume of lighter and fresher water that moves gener-
ally eastward toward Block Island Sound (29» 51 » 52).

10

20

30

I.

\

/

1

FLOOD ^—
EBB O —

— o

J^

J\

cr

60

go

100 120

CENTIMETERS PER SECOND

140

160

Figure 17. Observations of tidal current speed at various depths,
ments made at an anchor station in east-central Long Island Sound
(Lat 4l°11.9'N, Long. 72°29.^'W) in 1953. After Riley (1956, Fig.

Measure-

7)

39

Measurements of both surface and bottom currents over many tidal
cycles (33i ^9) show that in the central part of the Sound the tidal current
patterns are elliptical and counterclockwise in direction. Because of the
effect of coastal topography, tidal currents along the coast are almost paral-
lel to the shoreline. The significant vertical differences in tidal currents
are that ebb tides are stronger at the surface than at depth and flood tides
are weaker at the surface than at depth as shown on Figure 17. In the deep
water of the central Sound tidal current speeds regularly exceed 30 centi-
meters per second (1 foot per second) near the bottom (written communication,
Gordon and Pilbeam, 1973).

The eastern part of Long Island Sound contains a two-layered trans-
port system where a less dense, less saline surface layer moves eastward into
Block Island Sound at an average speed of 2.8 nautical miles per day. This
water is replaced by more saline and dense bottom water that flows westward
into Long Island Sound at an average speed of 0.6 nautical miles per day.
Recent investigations on currents at the eastern end of the Sound (5^) indi-
cate (1) that there is a predominant inflow in the lower two thirds of the
water column in deep portions of The Race over a tidal cycle, (2) there is a
net outflow in the shallower remainder of the eastern passage between Orient
Point and Fishers Island, and (3) the inflow and outflow pattern suggest there
is a tidal-driven counterclockwise circulation in the eastern third of Long
Island Sound. Detailed information on the duration and variability of the
two-layered transport system at the eastern margin of the Sound is not yet
available. The interchange although complex in detail is apparently controlled
by the fresh-water inflow. The total annual inflow of water from Block island
Sound has been tentatively estimated at 3.8 times the total volume of Long
Island Sound (29) .

Moving westward into the central part of the Sound the circula-
tion system becomes less dynamic. There is decreasing transport in the
bottom layers principally because of upwelling and near shore mixing. Accord-
ing to Gordon and Pilbeam (written communication, 1973), the bottom water flows
westward into the central Sound principally along the north side of Six Mile
Reef near CI inton, becomes mixed with Connecticut River water and follows a
west-southwest course along the Connecticut shore. Inshore of the 10-fathom
(60 foot) curve the flow is toward the coast. The nontidal flow rate of near
bottom waters is as high as 5 kilometers (3.1 miles) per tidal cycle in the
deeper water and decreases toward either shore. Recent studies {]k) indicate
that upwelling of bottom waters occurs along the Connecticut shore between
New Haven and Old Saybrook and in coastal Long Island between Mattituck inlet
and Orient Point. There is also an offshore movement of surface water away
from the Connecticut coast. The net flow of near-surface waters is eastward
from the central to the eastern part of the Sound. The general net flow
pattern for eastern and east-central Long Island Sound is shown on Figure 18.

Hardy (11) characterized the waters of the central part of the
Sound, west of the Mattituck Sill (see Fig. 15), as seasonally homogeneous
probably because of vertical mixing due to tidal currents and wind. Mixing
between the bottom and surface waters occurs along both shores and in the
vicinity of Six Mile Reef (written communication, Gordon and Pilbeam, 1973).
Salinity stratification, however exists at least part of the time in the
central Sound.

40

mVERHE/IO

LONG ISLAND

ATLANTIC OCEAN

Figure 18. Conceptualized view of the essential features of the net flow in
eastern Long Island Sound and Block island Sound. Black arrows depict net
bottom flow and white arrows net surface flow. After Hollman and Sandberg
(1972).

Water fl
Bottom water enters
Shoal (wr i tten commu
fresh water enters f
of water from the Ea
less than the origin
transport system at
ly fresh water flowi
north shore of Long
River.

ows into western Long Island Sound from both directions.
from the east principally in the area south of Stratford
nication, Gordon and Pilbeam, 1973) while relatively
rom the East River. The recently verified net transport
st River into Long Island Sound {]]_) may be significantly
al estimate of 1100 cubic meters per second (29). The
the western end of the Sound is two-layered with relative-
ng eastward into the Sound and then primarily along the
Island while bottom water flows westward into the East

Western Long Island Sound waters are reported to be well mixed
internally but poorly mixed with the water to the east. From Hempstead Sill
(see Fig. 15) to the East River, however, the water exhibits vertical tempera-
ture, salinity and density stratification (11).

k]

Riley (28, 29) and others have attempted to estimate the residual
volume transport through various parts of the Sound or for one cross section
for various periods of time. Because of incomplete data the calculations are
very uncertain and continuous monitoring of currents are required to give
reasonable estimates of transport.

The vertical movement of the water surface in the Sound results
from the periodic tidal oscillations, from waves produced by wind and over
long periods by changes in sea level. Factors influencing the heights of
tides, abnormally high tides and storm generated waves are discussed in a
separate report prepared for this study by the Dept. of the Army, Corps of
Engineers (39) .

Long-term changes in sea level over the last 10,000 to 15,000
years have produced extensive submergence of the coast (2). Tide gage records
and tidal benchmark data indicate that sea level may still be rising at a
rate of approximately 1 foot per century.

6.3 Estuaries

Estuaries are sometimes defined as the seaward ends of river
valleys that contain salty water.' Ocean tides affect the streamflow and
flow may be either upstream or downstream depending on location, tide and
fresh water inflow conditions. The major estuaries in the region are the
Connecticut, Thames, Housatonic and Quinnipiac. Studies {Sj ]Sj 32) indicate
that there is a two-layer transport system in the lower parts of these
estuaries. Fresh water flows seaward near the surface while the tides move
denser saline water upstream along the river bottom. Salinity generally
increases downstream and top to bottom at any point in the brackish part of
the estuary. The distribution of salinity changes with the tidal stage and
the amount of fresh water inflow.

In the largest estuary, the Connecticut, saline water may reach
15 miles upstream from the mouth (J6} and tidal effects may extend upstream
approximately 60 miles. The upstream extent of salinity and tidal influence
is generally controlled by the amount of fresh-water inflow. During periods
of high fresh-water inflow (greater than 100,000 cfs), saline water is flushed
to the mouth of the river and the tide-affected reach extends upstream only
30 miles. Figure 19 shows the effect of different river discharge conditions
on chemical quality.

In the second largest estuary, the Thames, tidal effects and
saline water extend upstream to Norwich. Information on the salinity dis-
tribution and its variability in this estuary is contained in a recent report
by Soderberg and Bruno (32) . The Housatonic and Quinnipiac estuaries extend
upstream 12 and 10 miles respectively.

1 - Another commonly used definition is: a semi -enclosed coastal body of

water which has a free connection with the open sea and within which sea
water is measurably diluted with fresh water derived from land drainage.

k2

East

Haddam

Bridge

Essex ISaybrook
IShoal Bridge

o/o, o;,' ■ /^^rXTf^^m^ ^i ''^' ''''-

57 m'/sec (2000cfs)

.y j/r^yj^^

0,01 q.i ■ ^v -fl-^eV/^^o^^,^

29 Sep 1935

168 mVsec (5920 cfs)

'001 OI'J

18 Aug 1935

218 mVsec (7710 cfs)

25 July 1935

264 mVsec (9320 cfs)

12 Jun 1935

504 m'/sec (17,800 cfs)

0.01

13 Apr 1937
01 907 mVsec (32 ,500 cfs)

Figure 19. Chlorinity at high slack water in the lower part of the Connecti-
cut River during different river-discharge conditions. Chloride concentra-
tion in parts per thousand. Indicated discharge is for previous day at
Thompsonvi 1 le, Connecticut. After Meade (1966, Fig. 3).

Major estuaries and adjacent parts of the Sound receive a large
proportion of the pollutants entering the region and are therefore areas of
critical concern. The movement of water in estuaries is complex in that it
is controlled to various degrees by tidal motion and fresh-water inflow.
Flow information sufficient to permit predictions of the amount of pollutants
and the rate of transport through an estuarine reach and into the Sound is
generally not available. At present, continuous stage information in tide
affected rivers is restricted to the 25-mile long reach of the Connecticut
River between Hartford and Middle Haddam. This data collected by the U.S.
Geological Survey can produce flow information such as stage, upstream and
downstream discharge, water-surface profile and flushing time at any location
in a reach and for any period of time. Limited flow data is available for a
45-mile reach between Wilson and Essex while flow is continuously computed for
a 4-mile reach between Middletown and Middle Haddam.

43

7.0 WHAT THE STUDY WILL DO NEXT

The information on sources and movement of water gathered in
the inventory phase of this study and summarized in this report will be
used in developing management plans. The material should be especially
useful for water quality, water supply and flooding. But it should also
be useful for other plans such as land use, erosion and sedimentation, and
ecological studies in assessing the impact of management on the existing
natural system.

The work group on sources and movements of water will help the
other work groups in four ways:

(1) By providing this summary report to all work groups and
by making the more detailed data upon which it rests available
as needed.

(2) in a passive way, by responding to work group requests
for supplementary information or interpretations.

(3) In an active way, by pointing out to the other work
groups ways in which information on sources and movements on
water might assist in solving their major problems. Some examples:

At the western end of the Sound, information on in-
flow and outflow is very poor; the direction and velocity
of flow varies in a poorly understood way according to
tidal phase, depth, buoyancy and other factors. However,
it is known that the net surface flow is towards the
Sound and the net bottom flow is out of the Sound,
Therefore, there is a potential capability, which needs
further investigation, of directing the flow of sewage
into or out of the Sound. This might be accomplished
by considering the combined effects of currents, out-
fall locations and outfall elevations in New York City,
and possibly by correlating sewage discharges there with
favorable phases of the tidal cycle.

In the center of the Sound with its complex gyre
patterns, the retention time of natural runoff and
sewage is relatively long as compared with the eastern
part of the Sound where they are swept much more rapidly
out to sea through The Race. Recognition of these gross
patterns might influence the priorities and degrees of
waste treatment in Bridgeport, New Haven, New London,
and cities along the Connecticut River. To the extent
that thermal effects of proposed power plants are
determined to be widespread and significant, the gross
circulation patterns should be a significant considera-
tion affecting site selection and outlet design.

kk

The worst water quality in the Sound is probably in
the metropolitan harbors where the direct pollution
effects on people are the most intense. In addition
to upgrading waste treatment systems, extending out-
falls into the Sound is sometimes suggested. Our
existing, generally poor knowledge of circulation
patterns might still be able to tell us something
about this approach, and more detailed localized
knowledge should be collected.

(4) By articulating the highest priority research needs.
Foremost among these are (a) the currently inadequate quanti-
fication of the dynamic circulation system within the Sound
and major estuaries especially at the western end of the Sound,
(b) the lack of climatologic data in the area over the Sound
itself, (c) the need to continually monitor the hydrologic
system of Long Island, and (d) the need for quantitative hydro-
geologic data on the mainland part of the study region. The
study team will evaluate the importance of the data deficiencies
and make specific recommendations for programs to acquire
necessary information. The proposed programs will consider on-
going studies and where possible be integrated with them.

k5

APPENDIX A

SELECTED REFERENCES

I.. Barksddle, H, C, D. O'Bryan and W. J. Schneider. Effect of Drought
on Water Resources in the Northeast. U.S. Geo). Survey Hydrologic
Atlas Zki, 1966.

2. Bloom, A. L. and M. Stulver. Submergence of the Connecticut Coast.

Science, v. 139, No. 3552, I963, pp. 332-33^.

3. Brumbach, J. J. The Climate of Connecticut, Connecticut Geol. Nat.

History Survey Bull. 99, 1965, 215 Pp.

U. Cervione, M. A., Jr., D. L. Mazzaferro and ft. L. Melvin, Water
Resources Inventory of Connecticut, Part 6, Upper Housatonic
River Basin. Connecticut Water Resources Bult. No. 21, I97Z, S** pp.

5. Cohen, P., 0. L. Franke and B. L. Foxworttiy. An Atlas of Long

Island's Water Resources. New York State Water Resources Comm.
Bull. 62, 1968, 117 pp.

6. Cohen, P., 0. L. Franke and N. E. McClymonds. Hydrologic Effects of

the 1962-66 Drought on Long Island, New York. U.S. Geol. Survey
Water-supply Paper 1879-F, 1969, I8 pp.

7. Connecticut State Department of Health. Analyses of Connecticut

Public Water Supplies, 7th edition, 1971, 67 pp.

8. De Luca, F. A., J. C. Hoffman, and E. R. Lubke. Chloride Concen-

tration and Temperature of the Waters of Nassau County, Long
Island, New York. New York State Water Resources Comm. Bull. 55,
1965, 35 pp.

9. Duxbury, A. C. A Hydrographic Survey of New Haven Harbor 1962-1963.

Connecticut Water Resources Bull. No. 3A, \3(>i*, 18 pp.

10. Franke, 0, L. and N. E. McClymonds. Summary of the Hydrologic Situa-
tion on Long Island, New York as a Guide to Water-Management
Alternatives. U.S. Geol. Survey Prof. Paper 627-F, 1972, 59 pp.

1). Hard^ C. D. Movement and Quality of Long Island Sound Waters. Tech.
RepK No. 17, Mar. Sci. Res. Cent., State University of New York,
Stony Brook, 1972, 66 pp.

12. Heath, R. C, B. L. Foxworthy and P. Cohen. The Changing Pattern of

Ground-Water Development on Long Island, New York. U.S. Geol. Sur-
vey Circular 52i|, I966, ID pp.

13. Hershfield, 0. H. Rainfall-Frequency Atlas of the United States for

Durations from 30 Minutes to 2l* Hours and Return Periods from I to
100 Years. U.S. Weather Bureau Tech. Paper 40, 1961, 115 PP-

I'l. Hollman, R. and G. R. Sandberg. The Residual Drift in Eastern Long
Island Sound and Block Island Sound. New York Ocean Sc I . Lab.
Technical Rept. No. 0015, 1972, 19 Pp.

15. Crutche.-, H. L. and J. T. Quinlan. Atlantic Tropical Cyclone Strike

Probabilities, v. 1, 24-Hour Movement, v. 11, ^S-Hour Movement,
V. in, 72-Hour Movement. NOAA, Environmental Data Service, 1971.

16. Meade, R. H. Salinity Variations in the Connecticut River. Water

Resources Research, v, 2, No. 3, 1966, pp. 567-579-

17. Miller, J. F. and R. H. Frederick. The Precipitation Regime of Long

Island, New York. U.S. Geol. Survey Prof. Paper 627-A, 1969, 21 pp.

18. National Oceanic and Atmospheric Administration, Environmental Data

Service. CI imatological Data, New England and C1 imatological Data,
New York, issued monthly.

19. National Oceanic and Atmospheric Administration, National Weather

Service. Water Supply Outlook for the Northeastern United States,
issued monthly,

. Average Monthly Weather Outlook, issued

nthly.

National Oceanic and Atmospheric Administration, National Ocean Sur-
vey (formerly U.S. Coast and Geodetic Survey). Nautical Charts
for Long Island Sound Region, issued periodically. Contained in
Nautical Chart Catalog No. 1 NOS, 1973-

National Oceanic and Atmospheric Administration, National Ocean Sur-
vey {formerly U.S. Coast and Geodetic Survey). Tidal Current
Charts, Block Island Sound and Eastern Long Island Sound, 1st ed.,
1972, 29 pp.

National Oceanic and Atmospheric Administration, National Ocean Sur-
vey (formerly U.S. Coast and Geodetic Survey), Tide Tables, High
and Low Water Predictions, issued annually. East Coast of North
and South America including Greenland.

Palmer, W. C, Meteorological Drought. U.S. Weather Bureau Research
Paper No. U5., 1965.

PerlmuCter, N. M. and F. A. DeLuca. Availability of Fresh Ground
Water, Montauk Point Area, Suffolk County, Long Island, New York.
U.S. Geol. Survey Water-Supply Paper I6I3-B, 1963, 39 pp.

Perlmutter, N. M, and J. J. Geraghty. Geology and Ground-Water Con-
ditions In Southern Nassau and Southeastern Queens Counties, Long
Island, New York. U.S. Geol. Survey Water-Supply Paper I613-A,
1963, 205 pp.

U2.

43.

Randall, A. D., M. P. Thomas, C. E. Thomas, Jr. and J. A. Baker.
Water Resources Inventory of Connecticut, Part I, Quinebaug River
Basin. Connecticut Water Resources Bull. No. 8. 1966. 10? pp

Riley, G. A. Hydrographic and Biologic Studies of Block Island Sound,
Hydrography of the Long Island and Block Island Sounds- Bull,
Bingham Oceanogr. Coll., \^ (3), 1952, pp. 5-39.

. Oceanography of Long Island Sound, 1952-1954, II.

Physical Oceanography. Bull. Bingham Oceanogr. Coll., v. 15,

1956, pp. 15-46.

. Transport and Mixing Processes in Long Island Sound.

Bull. Bingham Oceanogr. Coll., v. 19, 1967, pp. 35-61.

Ryder, R. B., M. A. Cervione, Jr., C. E. Thomas, Jr. and M. P. Thomas,
Water Resources Inventory of Connecticut, part 4, Southwestern Coast-
al River Basins; Connecticut Water Resources Bull. No. 17, 1970,
54 pp.

Soderberg, E. F. and A. B. Bruno. Salinity Distribution in Ihe Thames
River, New London to Norwich, Connecticut. Naval Underwater Sys-
tems Center Report No. 4005, 1971, 87 pp.

Swanson, R. L. Some Aspects of Currents in Long Island Sound. Un-
published Doctoral Dissertation, Oregon State University, 1971,

150 pp.

Swarzenski, W. U. Hydrology of Northwestern Nassau and Northeastern
Queens Counties, Long Island, New York: U.S. Geol. Survey Water-
Supply Paper 1657, 1963, 90 pp.

Thorn, H, C. S. Distribution of Extreme Winds in the United States,
Amer. Soc . Civil Eng. Trans., v. 126, pt 2, I96I, pp. 450-466.

Thomas, M. P., G. A. Bednar, C. E. Thomas, Jr. and W. E. Wilson,
Water Resources Inventory of Connecticut, part 2, Shetucket River
Basin Connecticut Water Resources Bull. No. II, 1967, 96 pp.

Thoiras, C. E., Jr., H. A. Cervione, Jr. and I . G. Grossman, Water
Resources Inventory of Connecticut, part 3, Lower Thames and South-
eastern Coastal River Basins. Connecticut Water Resources Bull.
No. 15, 1968, 105 pp.

Thomas, H, E. The Heteorologic Phenomana of Drought in the Southwest.
U.S. Geol. Survey Prof. Paper 372-A, 1962, 42 pp.

U.S. Dept. of the Army, Corps of Engineers. Tidal hydrology. Long
Island Sound Interim Memo. No. COE 2, 1973, 14 pp.

U.S. Coast and Geodetic Survey (now National Ocean Survey) and U.S.
Fish and Wildlife Service. Bathymetric maps, Long Island Sound,
1967, 0808N-53, O8O8N-55.

U.S. Geological Survey. Water Resources Data for Connecticut. Issued
annual ly .

Water Resources Data for New Yo
Water Resources Conditions in Ci

Issued annually.
lecticut. Issisd

Water Resources Summar'

Long Island, N.Y.

47.
48.

49.

U.S. Public Health Service. Dr i nki ng Water Standards, 1962: U.S.
Public Health Service Pub. 956, 1962, 6I pp.

U.S. Weather Bureau, Climatic Guide for New York City, New York and
Nearby Areas. CI Imatography of the United States No. 40-26, 1958..

Climates of the States, New York: CI imatography

of the United States 60-30, I960.

Meade, R, H. The Coastal Environment of New England. New England
River Basins Comm., 1971, 47 pp.

Gordon, R. B. and C. Pllbeam, Tides and Circulation in Central Long
Island and Sound (abstract). E © S, Trans. Amer. Geophys. Union,
V. 54, No. 4, 1973, pp 301-302.

LeLacheur, E. A. and J. C. Sammons, Tides and Currents in Long Island
and Block Island Sounds. U.S. Coast and Geodetic Survey Spec.
Publication No. 174, 1932, pp 1-184.

Garvlne, R. W. Physical Features of the Connecticut River Outflow
during High Discharge j_n Determination of Budgets of Heavy Metal
Wastes in Long Island Sound, 1st Annual Rept., pt. II, appendix
0, Univ. of Conn. Marine Sci. Inst., pp D-1-54.

fluggles, F. H,, Jr. Plume Development In Long Island Sound Observed

by Remote Sensing (ERTS-l) _hi Symposium on Significant Results

Obtained from the Earth Resources Technology Sate1IIte-l, NASA

SP-327 v. I, sec. fl, 1973, PP I299-I303.

Paskausky, D. F., A. J. Nawalk and D. L, Murphy. Circulation In
Eastern Long Island Sound J_n Determination of Budgets of Heavy
Metal Wastes In Long Island Sound, 1st Annual Rept., pt. I,
appendix C, Univ. of Conn. Marine Sci. Inst., pp C-1-24.

A-1

APPENDIX B

GLOSSARY

Air mass - A widespread body of air, the properties of which can be
identified as having been established while that air was situated
over a particular region of the earth's surface and having undergone
specific niodi f ications while in transit away from the source region.

Anticyclone - An atmospheric closed clockwise circulation. Because
clockwise circulation and high atmospheric pressure usually coexist,
the terms anticyclone and high are used interchangeably in common
practice.

Artesian conditions - Ground water that is under sufficient pressure to
rise above the level at which it is encountered by a well, but which
does not necessarily rise to or above the surface of the ground.

Bathymetr ic - Relating to measurement of depths; usually applied to the
ocean.

Bedrock - The solid rock, commonly called "ledge," that forms the earth's
crust.

Chemical quality of water - The quantity and kinds of material in suspen-
sion or solution and the resulting water properties.

Chlor ini ty - The chloride content of sea water, measured by mass, or
grams per kilogram of sea water, and including all the halides.

CI imat ic year - A continuous 12-month period, April 1 through March 31,
during which a complete annual streamflow cycle takes place from high
flow to low and back to high flow. It is designated fay the calendar
year in which it begins.

Continuous-record gaging station - A site on a stream at which continuous
measurements of stream stage are made by automatic equipment or made man-
ually at least once a day. These records are converted to daily flow
after calibration by flow measurements.

Cubic feet per second (cfs) - A unit expressing rate of discharge. One

cubic foot per second is equal to the discharge of a stream 1 foot wide
1 toot deep flawing at an average velocity of 1 foot per second.

Cycloqenesi s - Any development or strengthening of cyclonic circulation
in the atmosphere.

Cyclone - An atmospheric closed counterclockwise circulation.

Seven-day ten-year low flow - The mean daily stream flow for seven consec-
utive days occurring on an average once in ten years.

Degree day - Generally, a measure of the departure of the mean daily tem-
perature from a given standard: one degree day for each "f of departure
above or below the standard during one day. Degree days are accumulated
over a "season" at any point during which the total can be used as an
index of past temperature effect upon some quantity, such as plant growth,
fuel consumption, power output, etc.

Pi ssolved sol ids - The residue from a clear sample of water after evapo-
ration and drying for one hour at l80''C; consist primarily of dissolved
mineral constituents, but may also contain organic matter and water of
crystal 1 izat ion.

Drainage area of a stream at a specified location is that area, measured
in a horizontal plane, enclosed by a topographic divide from which direct
surface runoff from precipitation normally drains by gravity into the
stream above the specified point.

Estuary - A bay, as the mouth of a riverj where the tide meets the river
current,

Evapotranspiration - Discharge of water to the atmosphere by direct evapo-
ration from the land and by transpiration from plants.

Extratropical cyclone - Any cyclonic-scale storm that is not a tropical
cyclone.

Frequency - The rate of recurrence of an event in periodic motion: The
number of times a specified event occurs in a given series of observations.

Ground water - Uater in the saturated zona.

Ground-water discharge - The discharge of water from the saturated zone
by 1) natural processes sUch as ground-water runoff and ground-water evapo-
transpiration and 2^ discharge through wells and other man-made structures.

Ground-water divide t A 1 ine on a water table on each side of which the
water table slopes downward in a direction away from the line. In the
vertical dimension, a plane across which there is no ground-water flow.

Ground-water outflow - All natural ground-water discharge from a drain-
age area exclusive of ground-water evapotranspiration.

Hardness, of water - The property of water generally attributable to salts
of the alkaline earths. Hardness has soap-consuming and encrusting pro-
perties and is expressed as the concentration of calcium carbonate (CaCOo)
that would be required to produce the observed effect.

Hydraulic conductivity - A measure of the ability of a porous medium to
transmit a fluid.

Hydrogeology - The science that deals with subsurface waters and related
geologic aspects of surface waters.

Impermeable - Having a texture that -does not permit water to move through
it perceptibly under the head differences ordinarily found in subsurface
water.

Induced recharcje - The amount of water entering an aquifer from an adja-
cent surface-water body by the process of induced infiltration.

Injection wel 1 - A well into which water is pumped.

Isotherm - A line of ^ual or constant temperature.

Isopleth - A line on a map connecting points at which a given variable has
a specified constant value.

Knot - The unit of speed In the nautical system; one nautical mile per
hour. It is equal to 1.1508 statute miles per hour or 0.51'+'* meters per
second.

Milliqrams per liter (mq/1) - A unit for expressing the concentration of
chemical constituents in solution by weight per unit volume of water.

Palmer Drought Index - Provides a measure of drought severity as well as
duration. It treats drought severity as a function of accumulated

weighted differences between actual precipitation and the precipitation
requirements, where the requirement depends on the carryover of previous
rainfall as well as on the evapotranspiration, moisture recharge and run-
off that would be climatically appropriate for the particular time and
place being investigated.

Perennial stream - A stream that flows during alt seasons of the year.

pH - The negative logarithm of the hydrogen-ion concentrations. Ordinar-
ily a pH value of 7.0 indicates that the water is at Its neutral point;
values lower than 7-0 denote acidity, those above 7-0 denote alkalinity.

Recharge - The amount of water that Is added to the saturated zone.

Recurrence interval - The average interval of time between extremes of
streamflow, such as floods or droughts, that will at least equal in
severity a particular extreme value over a period of many years.
FrequencVf a related term, refers Eo the average number of such extremes
during the same period. The date of a drought or flood of a given magni-
tude cannot be predicted, but the probable number of such events during
a reasonably long period of time may be estimated within reasonable limits
of accuracy.

Runoff - That part of the precipitation that appears In streams. It is
the same as streamflow unaffected by artificial diversions, storage, or
other works of man in or on the stream channels.

Sal ini ty - A measure of the quantity of total dissolved solids in water.

Salt-water encroachment - The phenomenon occurring when a body of salt
water, because of its greater density, invades a body of fresh water.

Saturated thickness - Thickness of an aquifer below the water table.

Saturated zone - The subsurface zone in which all open spaces are filled
with water. The water table is the upper limit of this zone and the water
in it is under pressure greater than atmospheric.

Sedimentary rock - Rocks formed by the accumulation of sediment.

Specific capacity, of a well - The rate of discharge of water divided by
the corresponding drawdown of the water level in the well (gpm/ft) .

Stratified drift - A predominantly sorted sediment laid doun by or in
meltwater from a glacier; includes sand and gravel and minor amounts of
silt and clay arranged in layers.

Ti 1 1 - A predominantly nonsorted, nonstrat I f led sediment deposited direct-
ly by s glacier and composed of boulders, gravel, sand, silt, and clay
mixed in various proportions.

Tropical cyclone - The general term for a cyclone that originates over the
tropical oceans. Fully mature tropical cyclones range in size from 60
miles in diameter to well over 1,000 miles in diameter.

Uater table - The upper surface of the saturated zone.

Hater year - A continuous period October I through SsptanibEr 30 during
which a complete streamflow cycle takes place from low to high flew and
back to low flci'j. A water year is designated by the calendar year in
which it ends.

Wind rose - Any one of a class of diagrams designed to show the distribu-
tion of vjind direction experienced at a given location over a considerable
period; it thus shows the prevailing wind direction.

B=1

APPENDIX C

HYDROLOGIC AND CLIMATOLOGIC MAPS, GRAPHS AND TABLES

PREPARED FOR THE LONG ISLAND SOUND REGIONAL STUDY

Copies are on file at the offices of the New England River Basins Commission

1. Flood Prone Area Maps for the following quadrangles in Subregions I.

2, 3, *♦ and 5. Scale I 2*1,000.

Ansonia Haddam New Haven Scotland

Clinton Jewetl City Naugatuck Southbury

Colchester Long Hill Norwalk North Wallingford

Deep River Meriden Norwich We^tporl

Essex Middle Haddam old Lyme Uillimantic

Gui Iford Hoodus Plainf ield

II. Hydrologic maps for Subregions 6, 7, 8 and 9; all maps at 1 125,000
or I :25O,000 scale.

Lines of equal thickness - Hagothy aquifer

Contours of the upper glacial aquifer

Contours on the surface of the Magothy aquifer

Contours on the surface of the Raritan clay

Contours on the surface of the Lroyd aquifer

Contours on the surface of the bedrock

Elevation of water tables, March 1971

Piezometric surface of Lloyd aquifer, January 1972

selected geohydrolog ic sections

Piezometric surface at the base of the Magothy aquifer, March, 1972

a. Cross section of Long Island: Approximate time for ground water to
travel along section c-c from water table

b. The relation of heads of major aquifers
Isopach of Raritan day of the Raritan Formation
Isopach of Lloyd aquifer

Water quality of the Magothy aquifer
Isopach of saturated upper glacial aquifer
Hean-annual flow of all gaged streams
Mean-monthly flow of continuously gaged streams
Water quality of the Lloyd aquifer
Water quality of the upper glacial aquifer

Estimated average hydraulic conductivity of Magothy aquifer
Estimated average hydraulic conductivity of upper glacial aquifer
Patterns of ground-water development

Estimated average hydraulic conductivity of Lloyd aquifer
Transmissibi I i ty of Lloyd aquifer
Locations of stream gaging stations

Net change of ground-water levels as a result of the 1962-66 drought
Location of recharge basins in Naussau and Suffolk Counties, Long Island,

III. Hydrologic tables and maps for Subregions 1, 2, 3, k and S.

Ground-water availability; I 62,500 scale.

Drainage areas; 1 2*1,000 scale.

Average yearly runoff, 1 62,500 scale.

Monthly average runoff, peak runoff (return periods of) 100, 50, 25, 2

years, 7 day-10 year runoff; 1-62,500 scale.
Time of travel - Quinnipiac River (table)
Time of travel - Connecticut River (table)
Distribution of dissolved solids in ground water and streams at low flow;

1 125.000 scale.
Distribution of iron and manganese in ground water and streams at low

flow; 1 125,000 scale.
Distribution of hardness of ground water and streams at low flow;

I 125,000 scale.

IV. Three maps shewing locations of tidal bench marks for New York and
Connecticut.

V. Three lists of differences between Sea-Level Datum of 1929 (SLD) and
mean low water (MLW) for each location where tidal bench marks and geodetic
bench marks of the precise level net have been connected by spirit levels.

VI. Thirty-one tidal bench mark sheets giving descriptions to aid in
recovery of the marks and tide information. Mean high water (MHW) and
mean tide level (MIL) are given as related to MLW. Mean range can be
obtained as the difference between MHW and MLW.

VII. Tide Tables, East Coast of North and South America showing time and
differences in relation to reference stations as well as ranges. Nos.
1187-1263 and 133l-l'*07 are applicable to Long Island Sound.

A. Tidal current charts for:

Long Island Sound and Block Island Sound

Slock Island Sound and Eastern Long Island Sound

Western Long Island Sound (will be available in January 197**)

B. Tidal current diagrams for 1973 to accompany the above charts
IX. Volume of water in Long Island Sound

X. Bathymetric data

A. Bathymetric contour maps of Long Island Sound (C t CS 0808n-5l,
53, and 55)

S. Fourteen hydrographic survey sheets of surveys conducted within

Long Island Sound since the compilation of the Bathymetric maps

H-89i»9 (1967) H-8997 (1968I H-9O88 (1969) ■

H-8951 (1967) H-9008 (1968) H-9089 (1969) ''

H-8952 (1967) H-9093 (1968) H-908I (1970) '

H-8967 (1967) H-9030 (1968) H-9012 (1971)

H-8996 (1968) H-9O87 (1969)

These sheets are in the process of being verified.

C. Nautical-charts

C 6 CS 1212 Long Island Sound eastern part

C 6 CS 1211 Block Island Sound

C & GS 1213 Long Island Sound western part

Fresh water inflcM into Long Island Sound

Map of New York State sewage treatment facilities discharging to
ing Island Sound

A. Reference to bedrock, surficial deposits and ground-water resources

of New York State in the Long Island Sound Study area.

B. List of Geological publications of the New York Stale museum

C. Resume of investigations of the marine geology of the environs of

Long Island, New York

Listing of the available historical precipitation data.
Bedrock contour maps of major river estuaries, 1 21*, 000 scale,

A. Bedrock contour map of the New London quadrangle

B- Bedrock contour map of the New Haven quadrangle

C. Bedrock contour map of the Mi Iford quadrangle

D. Bedrock contour map of the Old Lyme quadrangle

CI Imatological maps and graphs

Mean annual temperature
Mean annual temperature range

Annual march of the standard deviation of mean temperatures for 5
stations

Long-term variations in precipitation at New London, Conn., water

years 1887-1967
Long-term variations in precipitation at New Haven, Conn., water

years 1887-1967
Mean annual snowfall

Average length of the freeze free season (in days)
Observed frequency of tropical storm and hurricane occurrence in and

near the Long Island Sound Study area
Maximum annual number of thunderstorms
Mean monthly radiation at Central Park, N.Y., Sayville, L,l, and

Newport, R.I.
Annual march of mean cloudiness in tenths for 2 stations on Long Island
Wind roses for each of four seasons at 5 stations

CI imatological tables

Monthly and annual mean max imum temperature

Monthly and annual mean minimum temperature

Monthly and annual mean temperature

Monthly and annual extreme maximum temperature statistics

Monthly and annual extreme minimum temperature statistics

Monthly and annual mean, greatest and least number of days with maxi-
mum fmperature less than or equal to 32", *t5°, 80", 90°F

Monthly and annual mean, greatest and least numbers of d.-iys with mini-
mum temperatures less than or equal to hS" , 36°, 32°, 2W , 16", 0"F

Air conditioning design data

Air conditioning critera data

Heating design data

Mean monthly and seasonal heating degree-days (base 65"F)

Mean monthly and seasonal cooling degree-days (base 65"F)

Probability dates of last spring and first fall occurrence of 32°,
2k , and 16' F

Mean monthly and seasonal growing degree-days (base 50"F)

Mean monthly and seasonal growing degree-days (base '40°F)

Monthly and annual greatest, least and mean number of days with tem-
perature moving through the 32"F threshhold ( f reeze-thaw)

Expected recurrence intervals of maximum point rainfall amounts

Extreme 2*4-hour precipitation statistics

Extreme 2U-hour snowfall statistics

Greatest monthly and annual precipitation for entire period of record

Least monthly and annual precipitation for entire period of record

Mean, greatest and least monthly and annual number of days with pre-
cipitation equal to or greater than ,01, .10, .50 and 1.00 inches

Mean and greatest monthly and seasonal snowfall

Mean and greatest monthly and annual number of days with snowfall equal to
or greater than 1, 2, 1* and 8 inches

Snow cover statistics and probabilities

Probability that an existing tropical cyclone centered at a specified
latitude and longitude in the month shown will be within the Long
Island Sound Study area after 72, I48 and 2U hours

Chronology of Long Island Sound Study area tornadoes

Humidity statistics for I* stations for January, April, July and October

Frequency of occurrence of sky cover
Distribution of runs of dry days

C-1

APPENDIX D

LOCATION OF

STATIONS USED IN LONG ISLAND SOUND REGION CL 1 MATOLOG I CAL ANALYSIS.
STATIONS IN PRIMARY NETWORK INDICATED BY SOLID CIRCLES.

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D-1

APPENDIX E

SUMMARY OF DISCHARGE RECORDS FOR MAINLAND STREAMS

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E-1

COORDINATING GROUP
LONG ISLAND SOUND REGIONAL STUDY
As of the date of this report

New England River Basins Commission

State of Connecticut

Conn. Coastal Zone Management Committee

Connecticut Office of State Planning

State of New York

Interstate Sanitation Commission

Tri-State Regional Planning Commission

Atomic Energy Commission

Department of Agriculture

Department of the Army, Corps of Engineers

Department of Commerce

Department of Housing and Urban Develop'nt

Department of the Interior

Department of Transportation

Environmental Protection Agency

Federal Power Commission

Nassau-Suffolk Regional Planning Board

Citizen Advisory Committee

Research/Planning Advisory Committee

Study Manager

-'■'R. Frank Gregg

Zell Steever

Senator George L. Gunther

Horace Brown

Edward A. Karath

Thomas R. Glenn

Richard DeTurk

Walter Belter

Robert Hill iard

John W. Lesl ie

Russel T. Norris

Nick M. Nibi

Mark Abel son

Captain A. T. Durgin

Walter M. Newman

Martin Inwald

Lee E. Koppelman

Roger Shope

Lawrence E. Hinkle, Jr.

'-'wVDavid A. Burack

"Chairman - ^'"VExecutive Secretary
WORK GROUP ON SOURCES AND MOVEMENT OF WATER

National Oceanic and Atmospheric Adm.

U.S. Geological Survey

U.S.D.A., Soil Conservation Service

U.S. Army, Corps of Engineers

U.S. Coast Guard

State of Connecticut

State of New York

Citizens Advisory Committee

Research/Planning Advisory Committee

"Cochairman

"John H. Thomas
Joseph J. Brumbach
Bruce Keck
"Frederick Ruggles
Robert Melvin
F. P. Haeni
Ellis Koch
D. A. Philbrook
Arthur F. Doyle
Cdr. C. R. Lindquist
Whitney Beals
Randolph M. Stel Ie
Edward F. Brickell
Roger Shope
Frank Bohlen

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