C 55.2: ES 8/5/ V.3 NOAA's Estuarine Eutrophication Survey Volume 3: North Atlantic Region \$6* /— \ z&Z July 1997 Office of Ocean Resources Conservation and Assessment National Ocean Service National Oceanic and Atmospheric Administration U.S. Department of Commerce Mi J The National Estuarine Inventory The National Estuarine Inventory (NEI) represents a series of activities conducted since the early 1980s by NOAA's Office of Ocean Resources Conservation and Assessment (ORCA) to define the nation's estuarine resource base and develop a national assessment capability. Over 120 estuaries are included (Appendix 3), representing over 90 percent of the estuarine surface water and freshwater inflow to the coastal regions of the contiguous United States. Each estuary is defined spatially by an estuarine drainage area (EDA) — the land and water area of a watershed that directly affects the estuary. The EDAs provide a framework for organizing information and for conducting analyses between and among systems. To date, ORCA has compiled a broad base of descriptive and analytical information for the NEI. Descriptive topics include physical and hydrologic characteristics, distribution and abundance of selected fishes and inver- tebrates, trends in human population, building permits, coastal recreation, coastal wetlands, classified shellfish growing waters, organic and inorganic pollutants in fish tissues and sediments, point and nonpoint pollution for selected parameters, and pesticide use. Analytical topics include relative susceptibility to nutrient discharges, structure and variability of salinity, habitat suitability modeling, and socioeconomic assessments. For a list of publications or more information about the NEI, contact C. John Klein, Chief, Physical Environ- ments Characterization Branch, at the address below. I The Estuarine Eutrophication Survey ORCA initiated the Estuarine Eutrophication Survey in October 1992. The goal is to comprehensively assess the scale and scope of nutrient enrichment and eutrophication in the NEI estuaries (see above) and to build a foun- dation of data that can be used to formulate a national response. The Survey is based, in part, on a series of workshops conducted by ORCA in 1991-92 to facilitate the exchange of ideas on eutrophication in U.S. estuaries and to develop recommendations for conducting a nationwide survey. The survey process involves the system- atic acquisition of a consistent and detailed set of qualitative data from the existing expert knowledge base (i.e., coastal and estuarine scientists) through a series of surveys, site visits, and regional workshops. The original survey forms were mailed to over 400 experts in 1993. The methods and initial results were evalu- ated in May 1994 by a panel of NOAA, state, and academic experts. The panel recommended that ORCA pro- ceed with a regional approach for completing data collection, including site visits with selected experts to fill data gaps, regional workshops to finalize and reach consensus, and regional reports on the results. The North Atlantic regional workshop was held in October 1996; this document, Volume 3, is the regional report. It was preceded by the South Atlantic (Volume 1, September 1996) and Mid-Atlantic (Volume 2, March 1997) reports. Site visits, regional workshops, and regional reports will be completed for the Gulf of Mexico, and West Coast in 1997. A national assessment report of the status and health of the nation's estuaries will be developed from the survey results. In addition, an "indicator" of ecosystem health will also be published. Both national products will require one or more workshops to discuss and reach consensus on the proposed methods for conducting these analyses. ORCA also expects to recommend a series of follow-up activities that may include additional and /or improved water-quality monitoring, and case studies in specific estuaries for further characterization and analysis. For publications or additional information, contact Suzanne Bricker, Project Manager, at the address below. Strategic Environmental Assessments Division 1305 East West Highway, 9th Floor SSMC-4, N/ORCA1 Silver Spring, MD 20910-3281 301/713-3000 http: / / www-orca.nos.noaa.gov NOAA's Estuarine Eutrophication Survey Volume 3: North Atlantic Region Office of Ocean Resources Conservation and Assessment National Ocean Service National Oceanic and Atmospheric Administration Silver Spring, MD 20910 Pennsylvania State University Libraries SEP 1 8 1997 Documents Collection U.S. Depository Copy July 1997 This report should be cited as: National Oceanic and Atmospheric Administration (NOAA), 1997. NOAA's Estuarine Eutrophication Survey. Volume 3: North Atlantic Region. Silver Spring, MD: Office of Ocean Resources Conservation and Assessment. 45 p. I ORCA Organization The Office of Ocean Resources Conservation and As- sessment (ORCA) is one of four line offices of the Na- tional Oceanic and Atmospheric Administration's (NOAA) National Ocean Service. ORCA provides data, information, and knowledge for decisions that affect the quality of natural resources in the nation's coastal, estuarine, and marine areas. It also manages NOAA's marine pollution programs. ORCA consists of three divisions and a center: the Strategic Environ- mental Assessments Division (SEA), the Coastal Moni- toring and Bioeffects Assessment Division (CMBAD), the Hazardous Materials Response and Assessment Di- vision (HAZMAT), and the Damage Assessment Cen- ter (DAC), part of NOAA's Damage Assessment and Restoration Program. Project Team Suzanne Bricker, Project Manager Christopher Clement Scot Frew Michelle Harmon Miranda Harris Douglas Pirhalla | Acknowledgments The Project Team would like to thank SEA Division Chief Daniel J. Basta, as well as Charles Alexander and C. John Klein of the SEA Division, for providing di- rection and support throughout the development of the report and the survey process. Our thanks also go to Elaine Knight of South Carolina Sea Grant for lo- gistical support during the North Atlantic Regional Workshop. Finally, we gratefully acknowledge Pam Rubin of the SEA Division for her editorial review. Contents Introduction 1 The Problem 1 Objectives 1 Methods 2 Next Steps 5 Regional Overview 6 The Setting: Regional Geography 6 About the Results 8 Algal Conditions 8 Chlorophyll a Turbidity Total Suspended Solids Nuisance Algae Toxic Algae Macroalgae Epiphytes Nutrients 10 Nitrogen Phosphorus Dissolved Oxygen 12 Anoxia Hypoxia Biological Stress Ecosystem Response 13 Primary Productivity Planktonic Community Benthic Community SAV Inter tidal Wetlands References 16 Estuary Summaries 18 Regional Summary. 38 Appendix 1: Participants 39 Appendix 2: Estuary References 41 Appendix 3: NEI Estuary List 45 Introduction This section presents an overview of how the Estuarine Eutrophication Survey is being conducted. It includes a statement of the problem, a summary of the project objectives, and a discussion of the project's origins and methods. A diagram illustrates the project process, and a table details the data being collected. The section closes with a brief description of the remaining tasks. For additional information, please see the inside front cover of this report. I About This Report This report presents the results of ORCA's Estuarine Eutrophication Survey for 18 estuaries of the North Atlantic region of the United States. It is the third in a series of five regional summaries that also includes the South Atlantic (NOAA, 1996), Mid-Atlantic (NOAA, 1997), Gulf of Mexico (NOAA, in prep.), and West Coast (NOAA, in prep.). A national summary of project results is also planned. The Survey is a component of ORCA's National Estuarine Inventory (NEI) — an on- going series of activities that provide a better under- standing of the nation's estuaries and their attendant resources (see inside front cover). The report is organized into five sections: Introduc- tion, Regional Overview, References, Estuary Summa- ries and Regional Summary. It also includes three ap- pendices. The Introduction provides background in- formation on project objectives, process, and methods. The Regional Overview presents a summary of find- ings for each parameter, and includes a regional map as well as maps illustrating the results for selected pa- rameters. Next are the Estuary Summaries — one-page summaries of Survey results for each of the 18 North Atlantic estuaries. Each page includes a narrative sum- mary, a salinity map, a table of key physical and hy- drologic information, and a matrix summary of data results. The Regional Summary displays existing pa- rameter conditions and their spatial coverage across the region. Appendix 1 lists the regional experts who participated in the survey. Appendix 2 presents the references suggested by workshop participants as use- ful background material on the status and trends of nutrient enrichment in North Atlantic estuaries. Ap- pendix 3 presents a complete list of NEI estuaries. I The Problem Between 1960-2010, the U.S. population increased, and is projected to continue to increase, most significantly in coastal states (Culliton et al., 1990). This influx of people is placing unprecedented stress on the Nation's coasts and estuaries. Ironically, these changes threaten the quality of life that many new coastal residents seek. One of the most prominent barometers of coastal en- vironmental stress is estuarine water quality, particu- larly with respect to nutrient imputs. Coastal and estuarine waters are now among the most heavily fertilized environments in the world (Nixon et al., 1986). Nutrient sources include point (e.g., waste- water treatment plants) and nonpoint (e.g., agricul- ture, lawns, gardens) discharges. These inputs are known to have direct effects on water quality. For ex- ample, in extreme conditions, excess nutrients can stimulate excessive algal blooms that can lead to in- creased metabolism and turbidity, decreased dissolved oxygen, and changes in community structure — a con- dition described by ecologists as eutrophication (Day et al., 1989; Nixon, 1995; NOAA, 1989). Indirect ef- fects can include impacts to commercial fisheries, rec- reation, and even public health (Boynton et al., 1982; Rabalais and Harper, 1992; Rabalais, 1992; Paerl, 1988; Whitledge and Pulich, 1991; NOAA, 1992; Burkholder et al., 1992a; Cooper, 1995; Lowe et al., 1991; Orth and Moore, 1984; Kemp et al., 1983; Stevenson et al., 1993; Burkholder et al., 1992b; Ryther and Dunstan, 1971; Smayda, 1989; Whitledge, 1985; Nixon, 1983). Reports and papers from workshops, panels, and com- missions have consistently identified nutrient enrich- ment and eutrophication as increasingly serious prob- lems in U.S. estuaries (National Academy of Science, 1969; Ryther and Dunstan, 1971; Likens, 1972; NOAA, 1991; Frithsen, 1989; Jaworski, 1981; EPA, 1995.). These conclusions are based on numerous local and regional investigations into the location and severity of nutri- ent problems, and into the specific causes. However, evaluating this problem on a national scale, and for- mulating a meaningful strategy for improvements, requires a different approach. |obj ectives The Estuarine Eutrophication Survey will provide the first comprehensive assessment of the temporal scale, scope, and severity of nutrient enrichment and eutrophication-related phenomena in the Nation's major estuaries. The goal is not necessarily to define one or more estuaries as eutrophic. Rather, it is to sys- tematically and accurately characterize the scale and NOAA's Estuarine Eutrophictttion Survey: Volume 3 - North Atlantic scope of eutrophication-related, water-quality param- eters in over 100 U.S. estuaries. The project has four specific objectives: 1. To assess the existing conditions and trends, for the base period 1970 to present, of estuarine eutrophication parameters in 129 estuaries of the contiguous United States; 2. To publish results in a series of regional reports and a national assessment report; 3. To formulate a national response to identified problems; and 4. To develop a national "indicator" of estuarine health based upon the survey results. ORCA also expects to recommend a series of follow- up activities that may include additional and/or im- proved water-quality monitoring, and case studies in specific estuaries for further characterization and analysis. | Methods The topic of estuarine eutrophication has been receiv- ing increasing attention recently in both the scientific literature (Nixon, 1995) and in the activities of coastal resource management agencies. In the United States, investigators have generated thousands of data records and dozens of reports over the past decade that docu- ment seasonal and annual changes in estuarine water quality, primary productivity, and inputs of nutrients. The operative question for this project is how to best use this knowledge and information to characterize these parameters for the contiguous United States. Preparing for a national survey To answer this question, ORCA conducted three work- shops in 1991-92 with local and regional estuarine sci- entists and coastal resource managers. Two workshops, held at the University of Rhode Island's Graduate School of Oceanography in January 1991 (Hinga et al., 1991), consisted of presentations by invited speakers and discussions of the measures and effects associated with nutrient problems. The purpose was to facilitate the exchange of ideas on how to best characterize eutrophication in U.S. estuaries and to consider sug- gestions for the design of ORCA's proposed data col- lection survey. A third workshop, held in April 1992 at the Airlie Conference Center in Virginia, focused spe- cifically on developing recommendations for conduct- ing a nationwide survey. Given the limited resources available for this project, it was not practical to try to gather and consolidate the existing data records. Even if it were possible to do so, it would be very difficult to merge these data into a comprehensible whole due to incompatible data types, formats, time periods, and methods. Alterna- tively, ORCA elected to systematically acquire a con- sistent and detailed set of qualitative data from the existing expert knowledge base (i.e., coastal and es- tuarine scientists) through a series of surveys, inter- views, and regional workshops. Identifying the Parameters and Parameter Characteristics To be included in the Survey, a parameter had to be (1) essential for accurate characterization of nutrient enrichment; (2) generally available for most estuaries; (3) comparable among estuaries; and (4) based upon existing data and/or knowledge (i.e., no new moni- toring or analysis required). Based upon the work- shops described above and additional meetings with experts, 17 parameters were selected (Table 1). The next step was to establish response ranges to en- sure discrete gradients among responses. For example, the survey asks whether nitrogen is high, medium, or low based upon specific thresholds (e.g., high > 1 mg/ 1, medium > 0.1 < 1 mg/L low > 0 <0.1 mg/1, or un- known). The ranges were determined from nationwide data and from discussions with eutrophication experts. The thresholds used to classify ranges are designed to distinguish conditions among estuaries on a national basis, and may not distinguish among estuaries within a region. Temporal Framework: Existing Conditions and Trends For each parameter, information is requested for ex- isting conditions and recent trends. Existing conditions describe maximum parameter values observed over a typical annual cycle (e.g., normal freshwater inflow, average temperatures, etc.). For instance, for nutrients, ORCA collected information characterizing peak con- centrations observed during the annual cycle, such as those associated with spring runoff and /or turnover. For chlorophyll a, ORCA collected information on peak concentrations that are typically reached during an algal bloom period. Ancillary information is also re- quested to describe the timing and duration of elevated concentrations (or low levels in the case of dissolved oxygen). This information is collected because all re- gions do not show the same periodicity, and, for some estuaries, high concentrations can occur at any time depending upon conditions. For some parameters, such as nuisance and toxic algal blooms, there is no standard threshold concentration NOAA's Estuarine Eutrophication Survey: Volume 3 - North Atlantic PARAMETERS EXISTING CONDITIONS (maximum values observed over a typical annual cycle) TRENDS (1970-1995) CHLOROPHYLL A TURBIDITY SUSPENDED SOUDS NUISANCE ALGAE TOXIC ALGAE MACROALGAE EPIPHYTES • Surface concentrations: Hypereutrophic (>60 up, chl-a/l) High (>20, S60 ug chl-a/1) Medium (>5, £20 ug cnl-a/l) Low (>0. £5 ug cnl-a/l) • Limiting lectors to algal blomass (N, P, SI, light, other) • Spatial coverage1, Months of occurrence, Frequency ol occurrence2 • Secchl disk depths: Hlgh(<1m), Medium (12m, £3m). Low (>3m), Blackwater area • Spatial coverage1, Months ot occurrence, Frequency ol occurrence2 • Concentrations: Problem (significant Impact upon biological resources) No Problem (no significant impact) • Months of occurrence, Frequency of occurrence2 • Occurrence Problem (significant impact upon biological resources) No Problem (no significant Impact) • Dominant species • Event duration (Hours, Days, Weeks, Seasonal, Other) • Months of occurrence, Frequency of occurrence2 • Abundance Problem (significant Impact upon biological resources) No Problem (no significant Impact) • Months of occurrence, Frequency ot occurrence2 » Concentrations''''* » Limiting factors • Contributing laetors5 ■ Concentrations3* ■ Contributing factors5 (no trends information collected) • Event duration3.4 • Frequency of occurrence3'4 • Contributing factors5 ■ Abundance3'4 • Contributing factors5 in i- z UJ rr 2 NITROGEN PHOSPHORUS • Maximum dissolved surface concentration: High (21 mg/l), Medium (20.1, <1 mg/l), Low (20, < 0.1 mg/1) • Spatial coverage1, Months of occurrence • Concentrations3'4 • Contributing factors5 • Maximum dissolved surface concentration: High (20.1 mg/l), Medium (20.01, <0.1 mg/1). Low (20, < 0.01 mg/l) • Spatial coverage1, Months of occurrence • Concentrations3'4 • Contributing factors5 Z UJ o Q UJ > o co CO o ANOXIA (0 mg/1) HYPOXIA (>0mg/1 S 2mg/l) BIOL STRESS (>2mg/l £ Smg/l) • Dissolved oxygen condition Observed No Occurrence • Stratification (degree of Influence): (High, Medium, Low, Not a factor) • Water column depth: (Surface, Bottom, Throughout water column) • Spatial coverage1. Months of occurrence, Frequency of occurrence2 • Mln. avg. monthly bottom dissolved oxygen cone.3'4 • Frequency of occurrence3-4 • Event duration3-4 • Spatial coverage34 • Contributing factors5 PRIMARY PRODUCTIVITY PLANKTONIC COMMUNITY BENTHIC COMMUNITY SUBMERGED AQUATIC VEG. INTERTIDAL WETLANDS • Dominant primary producer. Pelagic, Benthlc, Other • Dominant taxonomlc group (number ol cells): Diatoms, Flagellates, Blue-green algae. Diverse mixture, Other • Dominant taxonomlc group (number ol organisms): Crustaceans, Molluscs, Annelids, Diverse mixture, Other • Spatial coverage1 • Temporal shift • Contributing factors5 • Temporal snift • Contributing factors5 • Temporal shift • Contributing factors5 • Spatial coverage3-4 • Contributing factors5 NOTES (1) SPATIAL COVERAGE (% of salinity zone): High (>50. £100%). Medium (>25, £50% ). Low (>10, £25%). Very Low (>0. £10% ). No SAV / Wetlands in system (2) FREQUENCY OF OCCURRENCE: Episodic (conditions occur randomly). Periodic (conditions occur annually or predictably). Persistent (conditions occur continually throughout the year) (3) DIRECTION OF CHANGE: Increase. Decrease, No trend (4) MAGNITUDE OF CHANGE: High (>50%, £100%). Medium (>25%. S50%). Low (>0%. £25%) (5) POINT SOURCE(S), NONPOINT SOURCE(S). OTHER Table 1: Project parameters and characteristics. NOAA's Estuarine Eutmphication Survey: Volume 3 - North Atlantic that causes problems. In these cases, a parameter is considered a problem if it causes a detrimental impact on biological resources. Ancillary descriptive informa- tion is also collected for these parameters (Table 1). the national survey. Salinity maps, based upon the NEI salinity zones, were distributed with the survey ques- tions for orientation. Updates and /or revisions to these maps were made as appropriate. Trends information is requested for characterization of the direction, magnitude, and time period of change for the past 20 to 25 years. In cases where a trend has been observed, ancillary information is requested about the factors influencing the trend. Spatial Framezvork A consistently applied spatial framework was also re- quired. ORCA's National Estuarine Inventory (NEI) was used (see inside front cover). For the survey, each parameter is characterized for three salinity zones as defined in the NEI (tidal fresh 0-0.5 ppt, mixing 0.5-25 ppt, and seawater >25 ppt). Not all zones are present in all NEI estuaries; thus, the NEI model provides a consistent basis for comparisons among these highly variable estuarine systems. Reliability of Responses Finally, respondents were asked to rank the reliability of their responses for each parameter as either highly certain or speculative inference, reflecting the robust- ness of the data upon which the response is based. This is especially important given that responses are based upon a range of information sources, from statistically tested monitoring data to general observations. The objective is to exploit all available information that can provide insight into the existing and historic condi- tions in each estuary, and to understand its limitations. The survey questions were reviewed by selected ex- perts and then tested and revised prior to initiating Collecting the Data Over 400 experts and managers agreed to participate in the initial survey. Survey forms were mailed to the experts, who then mailed in their responses. The re- sponse rate was approximately 25 percent, with at least one response for 112 of the 129 estuaries being sur- veyed. The initial survey methods and results were evaluated in May 1994 by a panel of NOAA, state, and academic eutrophication experts. The panel recommended that ORCA continue the project and adopt a regional ap- proach for data collection involving site visits to se- lected experts to fill data gaps and revise salinity maps, regional workshops to finalize and reach consensus on the responses to each question (including salinity maps), and regional reports on the results. The revised strategy was implemented in the summer of 1994, starting with the 22 estuaries of the Mid-Atlantic re- gion (Figure 1). Estuaries are targeted for site visits based upon the completeness of the data received from the original mailed survey forms. The new information is incor- porated into the project data base and summary ma- terials are then prepared for a regional workshop. Workshop participants are local and regional experts (at least one per estuary representing the group of people with the most extensive knowledge and insight about an estuary). In general, these individuals have either filled out a survey form and /or participated in Figure 1: Diagram of process. Survey Design 1992-93 National Survey Regional Strategy (to complete data dollectlon) — - — next region 1993-94 Site Visits Workshops N. Atlantic Gulf of Mexico Mid Atlantic West Coast S. Atlantic National Workshop(s) I ) Regional Reports 1995-96 Next Steps • national monitoring strategy? • research / case studies? i i • Inidicator Report • National Report 1996-97 NOAA's Estuarine Eutrophication Survey: Volume 3 - North Atlantic a site visit. Preparations include sending all regional data to participants prior to the workshop. Participants are also encouraged to bring to the workshop relevant data and reports. At the workshop, at least two workgroups are established based upon geography. The survey data and salinity maps for each estuary are then carefully reviewed. ORCA staff facilitate the discussions and record the results. At the close of the workshop, participants are asked to identify "critical" references such as reports and other publications that describe nutrient enrichment in one or more of the region's estuaries. Workshop results are summarized for each estuary and mailed to workshop participants for review. The data are then compiled for presentation in a regional re- port that is also reviewed by participants prior to pub- lication. The regional process, from site visits to publi- cation of a regional report, takes approximately six months to complete. Some tasks are conducted con- currently. J Next Steps Regional reports are in progress for the Gulf of Mexico and West Coast (Figure 1). A national assessment re- port of the status and health of the nation's estuaries will be developed from the survey results. The regional results and final national data base will be available over the Internet through ORCA's Web site (see inside front cover). Formulating a national response to es- tuarine nutrient enrichment, and developing a national "indicator" on coastal ecosystem health, will require one or more workshops to reach consensus on the methods and products resulting from these analyses. This work is currently scheduled for late 1997. ORCA is funding a series of small contracts with regional ex- perts to provide additional technical support for these tasks. Regional Overview This section presents an overview of the survey results. It begins with a brief introduction to the regional geography and a summary ofhow the results were compiled. Narrative summaries are then presented for each parameter in four subsections: Algal Conditions, Nutrients, Dissolved Oxygen, and Ecosystem/ Community Response. Figures include a regional map showing the location of the 18 North Atlantic estuaries, a summary of probable-months-of-occurrence by parameter, four maps illustrating existing conditions for selected parameters, and a summary of recent trends by estuary for selected parameters. The Setting: Regional Geography Northern Gulf of Maine The North Atlantic region, part of the New England Coastal Province, includes 18 esruarine systems, en- compassing more than 2,000 square miles of water sur- face area (Figure 2). The high energy coast is charac- terized by a rocky shoreline with numerous islands and small embayments. For this report, the region is divided into two physiographic subregions: Northern Gulf of Maine and Southern Gulf of Maine. The North- ern Gulf of Maine extends from the Maine-Canadian border to just south of Cape Elizabeth, Maine. The Southern Gulf of Maine extends south from Cape Elizabeth to Monomoy Island, Massachusetts, near Cape Cod (Beccasio, 1980). The 11 Northern Gulf of Maine esruarine systems char- acterized in this report encompass approximately 1,078 mi2 of water surface area. Formed largely by episodes of glacial advance and retreat, the subregion is charac- terized by a rocky coastline with wave cut cliffs and large, rocky islands. Most Maine estuaries are drowned river valleys containing many small embayments (Hunt, 1967). The macrotides in estuaries of this re- gion (20 feet in St. Croix River/Cobscook Bay) create an abundance of intertidal pool areas, and increase tidal mixing in the middle and upper sections of most estu- aries. The large tidal range has a significant influence on esruarine salinity variability which can range from Highlights of Regional Results (Note: Tidal fresh = 1%, Mixing = 3%, Seawater = 96% of regional surface area (2,039 mi2) Hypereutrophic concentrations (>60 ug/1) are not reported in any estuary. High or greater concentrations (>20 ug/1) are reported to occur from June to September in 4 of 18 estuaries, affecting up to 5% of the regional estuarine area. Concentrations did not change in 12 estuaries, and trends were unknown in 6 estuaries. High nitrogen concentrations (>1.0 mg/1) have been reported in Cape Cod Bay and Hampton Harbor Estuary, affecting up to 2% of the regional estuarine area. Concentrations are reported to have decreased in Penobscot Bay, increased in Cape Cod Bay urban embayments, shown no trend in 12 estuaries, and trends are unknown for 4 estuaries. Hypoxia is reported to be observed periodically from July through September in very small areas of Great Bay, Boston Harbor, and Cape Cod Bay, and episodically in Saco Bay. Stratification is influential on development of hypoxia in Great Bay and Boston Harbor. Spatial coverage of hypoxic occurrences decreased in Penobscot and Casco Bays, and remained the same for 10 estuaries. For 6 estuaries, trends in spatial coverage were unknown. : Toxic algal blooms, primarily Alexandrium, are reported : to occur in 11 of 18 estuaries, mostly on a periodic basis. J These blooms occur from June through September, j: though in some estuaries they begin in April. There was no change in the frequency of occurrence of toxic blooms for 11 estuaries, and trends were unknown for 7 estuaries. Increases and decreases were not reported for any estuary. High phosphorus concentrations (>0.1 mg/1) were not reported in any of the 18 estuaries. However, medium concentrations (0.01 - 0.1 mg/1) were reported in 14 estuaries, affecting up to 70% of the regional estuarine area. For most estuaries, medium concentrations occur October to March, but in some estuaries it is persistent year-round. Concentrations were reported as not changed in 12 estuaries, unknown in 5 estuaries, and decreased in Great Bay. No increases were reported. Anoxia is reported to be observed episodically throughout the water column in Kennebec/ Androscoggin Rivers, affecting less than 1% of the regional estuarine area, 37-76% of the tidal fresh zone, 5-10% of the mixing zone, and none of the seawater zone. Stratification was not reported to be a significant influence. Spatial coverage of anoxia was reported to have decreased in Penobscot and Casco Bays, remained the same in 11 estuaries, and trends were unknown for 6 estuaries. Increases in spatial coverage were not reported for any estuary. NOAA's Estuarine Eutrophication Survey: Volume 3 - North Atlantic Figure 2: Regional map of North Atlantic showing two subregions and 18 estuaries. 1) St. Croix River/ 2) Englishman Bay 3) Narraguagus Bay jfrf&Nr ^ 4) Blue Hill Bay 5) Penobscot Bay 6) Muscongus Bay 7) Damariscotta River 8) Sheepscot Bay 9) Kennebec /Androscogin Rivers 10) Casco Bay 11) Saco Bay Northern Gulf of Maine 12) Great Bay -13) Hampton Harbor 14) Merrimack River 15) Plum Island Sound Southern Gulf of Maine 18) Cape Cod Bay Atlantic Ocean •^s* - Monomoy Island North i 30 Miles 60 near zero to 33 ppt in a single tidal cycle. Freshwater inflow is dominated by discharge from the St. John, Kennebec, and Penobscot river systems. Depths for the Northern Gulf of Maine systems average approxi- mately 50 feet. Southern Gulf of Maine The seven Southern Gulf of Maine estuarine systems characterized in this report encompass 961 mi: of es- tuarine water surface area. The shoreline topography of this subregion also shows the distinctive features resulting from glacial advance and retreat (Figure 2). Dominant coastal features include Cape Cod, Massa- chusetts Bay, and Cape Ann. The coastline from Cape NCAA's Estuarine Eutrophicatkm Survey: Volume 3 - North Atlantic Elizabeth to Cape Ann is a succession of high-energy sand, cobble or gravel beaches and rocky shores; south of Cape Ann, beaches are sand or gravel. Tidal marshes are more extensive in the Southern Gulf of Maine es- tuaries than in Northern Gulf of Maine estuaries. In addition, variability in tidal range among Southern Gulf of Maine estuaries (7-9 feet) is significantly less than among Northern Gulf of Maine estuaries (9-20 feet). Depths are greatest in Massachusetts and Cape Cod Bays (average 77 feet) and decrease dramatically in the smaller estuaries to the north (11 feet in Merrimack River and Great Bay). Freshwater inflow is dominated by discharge from the Merrimack River and several smaller river systems such as the Salmon Falls, Parker and Neponsett. | About the Results The survey results are organized into four sections: Algal Conditions, Nutrients, Dissolved Oxygen, and Ecosystem Response. Each section contains a general overview followed by more detailed summaries for each parameter. This material is based on the indi- vidual estuary summaries presented later in this re- port. Regional patterns and anomalies are highlighted, and existing conditions and trends are reviewed. Prob- able months of occurrence by parameter and by salin- ity zone are presented in Figure 3 (page 9). Regional maps summarizing existing conditions for selected pa- rameters are presented in Figure 4 (page 11). A sum- mary of recent trends (1970-present) for all parameters is presented in Figure 5 (page 14). Data Reliability As described in the introduction, participants were asked to rank the reliability of their responses as ei- ther "highly certain" or "speculative inference." Over 93 percent of the responses are highly certain. Where relevant, speculative inferences are noted in the nar- rative below and on the estuary summaries that fol- low. A highly certain response is based upon tempo- rally and spatially representative data from long-term monitoring, special studies, or literature. A specula- tive inference is based upon either very limited data or general observations. When respondents could not offer even a speculative inference, the value was re- corded as "unknown." | Algal Conditions Algal conditions were examined in the North Atlan- tic region by characterizing existing conditions and trends for chlorophyll a, turbidity, suspended solids, nuisance and toxic algae, macroalgal abundance, and epiphyte abundance (Table 1, page 3). Maximum sur- face concentrations of chlorophyll a were not reported to reach hypereutrophic levels (>60 Ug/1) in the North Atlantic region, and high concentrations (>20 Ug/1) were reported in only 0.5, 1.5, and 3 percent of the tidal fresh, mixing, and seawater zones, respectively. Me- dium or greater concentrations of chlorophyll a (>5 Ug/1) were reported to occur in 75 percent of the region's tidal fresh zone surface area, 11 percent of the mixing zone, and 66 percent of the seawater zone. Me- dium to high turbidity conditions (secchi disk depths of < 3 meters) were reported to occur in up to 79 per- cent of the region's tidal fresh zone surface area, 51 percent of the mixing zone, and 9 percent of the sea- water zone. By contrast, high turbidity (secchi disk depths of < 1 meter) was reported to occur in 2 percent of the mixing zone, and not at all in the tidal fresh or seawater zones. Resource impacts from suspended solids were reported to occur in three of the estuaries in which high turbidity concentrations occur. Toxic al- gae appears to impact resources in 11 of 18 estuaries, primarily in the seawater zone. Nuisance algae re- source impacts are limited to Casco Bay and small ar- eas of Great Bay, but occur in all three zones. Macroalgal and epiphyte abundance impacts are fairly evenly distributed among the salinity zones and throughout the region, with macroalgae reported to impact resources in eight estuaries, and epiphytes in four estuaries. Chlorophyll a High concentrations (>20, <60 Ug/1) of chlorophyll a were reported in four estuaries, affecting a maximum of only 3 percent of the estuarine surface area (Figure 4). In contrast, medium or greater concentrations (>5 Ug/1) were reported to occur in 14 estuaries, over a maximum of 65 percent of the regional estuarine sur- face area. In the Northen Gulf of Maine subregion, high concentrations are reported only in the inner bays of Casco Bay from July through August. Medium con- centrations are typically reached from early spring through summer. St. Croix River/Cobscook Bay, Penobscot Bay, and Saco Bay were all reported to have low year-round concentrations of chlorophyll a. In the Southern Gulf of Maine estuaries, high concentrations are reached in Great Bay, Plum Island Sound, and Cape Cod Bay. The spatial extent was unknown for high con- centrations in Plymouth, Provincetown, and Barnstable Harbors, and for medium concentrations in Blue Hill Bay and Neponset River. Thus, the regional spatial extent of medium and high concentrations could be somewhat larger than reported. Elevated concentra- tions of chlorophyll a were reported to occur at some time during spring through fall, with three estuaries having elevated winter occurrences. X NOAA's Estuarine Eutrophication Survey: Volume 3 - North Atlantic There were no changes in chlorophyll a concentrations reported in 12 estuaries; in six, trends were reported as unknown. Turbidity Medium to high turbidity conditions (secchi disk depths of < 3 meters) were reported in 11 North At- lantic estuaries, covering 11 percent of the region's es- tuarine surface area, while high turbidity concentra- tions were reported to occur only in parts of Great Bay and Plum Island Sound (less than 1 percent of regional estuarine surface area). Since 1970, decreases in turbidity of a high magnitude have been reported for parts of St. Croix River/ Cobscook Bay and Casco Bay. The decreases were at- tributed to improvements or reductions in point-source discharges from paper mills, sewage-treatment plants, and fish-processing plants. A low-magnitude turbid- ity increase was reported in the seawater zone of En- glishman Bay. Conditions were unchanged in at least one zone in eight estuaries, and trends were unknown for seven estuaries. Suspended Solids Suspended solids were reported as impacting biologi- cal resources (e.g., submerged aquatic vegetation, fil- ter feeders, etc.) in two North Atlantic estuaries. The impacts are reported to occur persistently throughout the year in parts of Boston Harbor. In Cobscook Bay, problematic conditions were reported to occur episodi- cally from October through January due to scallop dredging. There were no reported impacts from sus- pended solids in 15 estuaries; conditions are unknown for the Merrimack River. Trends information was not collected for suspended solids. Figure 3: Probable months of occurrence by parameter and by salinity zone (average). This figure illustrates the probable months, over a typical annual cycle, for which parameters are reported to occur at tlieir maximum value. The black tone represents months where maximum values occur in at least 65 percent of the 18 North Atlantic estuaries for a particular salinity zone. For example, tidal fresh zones occur in 4 estuaries; therefore, a black tone indicates a maximum value was recorded in 2 or more estuaries. Similarly, for the mixing zone, black represents 10 or more estuaries, and for the seawater zone it represents 11 or more estuaries. Cray represents months where maximum values occur in 39 to 64 percent of the estuaries in that salinity zone, and unshaded boxes (white) represent months where maxi- mum values occur between 1 and 38 percent of the estuaries in that zone. "Months-of-occurrence" data were not collected for Ecosystem/Community Response parameters (i.e., primary productivity, planktonic community, benthic community, and SAV). TIDAL FRESH ZONE 4 ••tutri** MIXING ZONE 16 ••luanti SEAWATER ZONE 17 ••tuahaa Chi* Turbidity Suspended Solids Nuisance Algae Toxic Algae Macroalgae Epiphytes TDN TOP Anoxia Hypoxia Biological Stress JFMAUJIJASONO I I I I I alUM I I I th n n m H ; ' ! ' '! ™ rrri J F MA u jIj a • I o n d J F U 1 A U J J » S O N 0 1 1 | 1 1 MINI 1 1 1 1 1 1 III 1 1 I ] aimiv ii i i i i i i bHHH 1 1 1 1 1 1 1 1 I | J V j f y AUJJAtOND 1 1 1 1 1 1 1 1 1 1 III' 1 1 1 1 1 1 1 1 1 1 1 1 1 1 u 1 1 1 1 1 1 E 1 1 1 Ml J 1 1 1 aimiv i i i i i Bums SUM 1 1 aHV 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 J F I A J J A • O N 0 >65% ol the estuaries in each zone □ between 39S and 64S ot the estuanes in each rone □ between i N and 38N of the e*tue.r»e» tn each rone NOA.4 'a Estuarine Eutmphicatton Survey: Volume 3 - North Atlantic Nuisance Algae Nuisance dinoflagellates and Phaeocystis spp. were re- ported to episodically impact resources in Casco Bay for weeks at a time, during April and May. In Great Bay, Prorocentrum spp. were reported to occur episodi- cally in Spinney Creek. A diverse mixture of nuisance species episodically affects Salmon Falls/Cocheco Rivers for days at a time, from July through Septem- ber. Phaeocystis spp. and Prorocentrum spp. were re- ported as presently occurring in Massachusetts Bay, Boston Harbor, and Cape Cod Bay, but not at prob- lematic concentrations. There has been no reported trend in the duration or frequency of occurrence of nuisance algae events in 11 estuaries ca. 1970 to 1995. Trends were unknown for seven estuaries. Toxic Algae Resource impacts from toxic algae were reported to occur in nine of the 11 Northern Gulf of Maine estuar- ies. Alexandrium spp. occur periodically for weeks to months at a time, typically from spring through sum- mer in several estuaries; however, in the mixing zone of Narraguagas Bay, their timing and frequency have not been determined. Gymnodinium mikimotoi occurred for days in September of 1988 in Casco Bay inner bays. In Southern Gulf of Maine, Alexandrium impacts re- sources within Massachusetts and Cape Cod Bays, for weeks at a time. Northern Gulf of Maine Estuaries Northern Gulf of Maine estuaries are unique from the other North Atlantic estuaries due to their large tidal amplitude and the source of ni- trogen. The estuaries in Northern Gulf of Maine have a tidal amplitude that ranges from 20 feet in St. Croix River /Cobscook Bay, the easternmost estuary in this report, to nine feet in Saco and Caso Bays to the southwest. As a result, tidal mixing and oceanic exchange are significant in these estuaries. The other defining characteris- tic of these estuaries is that the main source of nitrogen comes from the inflow of Gulf of Maine deep water instead of from land-based sources. Unlike many estuaries in other regions, the drain- age basin has neither large centers of population (and thus little sewage-derived nutrients), nor large areas of agricultural land use that would provide nutrients through runoff (Garside et al., 1978; Fefer and Schettig, 1980). There has been no trend reported in the duration or frequency of occurrence of toxic algae events in 14 of the North Atlantic estuaries ca. 1970 to 1995. Toxic al- gae trends are unknown for four estuaries. Macroalgal Abundance Resource impacts from macroalgae were reported in at least one salinity zone of eight estuaries in the North Atlantic region. These impacts were reported to occur periodically in six estuaries and episodically in two, typically during the summer but sometimes starting in spring. Macroalgal abundance information was unknown for Merrimack River. Increases in macroalgal abundance were reported for seven estuaries. Trends for four of these estuaries were based in part on speculative inference. Conditions were reported to remain unchanged for five estuaries. Trends for six estuaries were unknown. Epiphyte Abundance Resource impacts from epiphytes were reported in the mixing zone of the St. Croix River, the East Bay por- tion of Casco Bay, Great Bay, and Boston Harbor. Im- pacts were reported to occur between July and Sep- tember on a periodic basis in St. Croix River and Bos- ton Harbor, and episodically in Great Bay. Frequency and timing for Casco Bay was not determined. Epi- phyte abundance information was unknown in Saco Bay, Merrimack River, and Cape Cod Bay urban embayments. Epiphyte abundance was speculated to have increased to a low extent from 1970 through 1995 in Great Bay. There were no reported epiphyte abundance trends in nine estuaries, and trends were unknown in the other eight. | Nutrients Nutrient concentrations in the North Atlantic region were characterized by collecting information on the existing conditions (maximum values observed over a typical annual cycle) and trends. The intent of the survey was to collect information for total dissolved nutrients, because these forms are what is available to the phytoplankton. Unless otherwise specified, nutri- ent information presented in this report refers to total dissolved nitrogen (TDN) and phosphorus (TDP), in- cluding the inorganic and organic forms. For five es- tuaries (Penobscot, Sheepscot, Casco Bays, Damariscotta River, and most of Great Bay), nitrogen concentrations are reported as dissolved inorganic ni- trogen (DIN). 10 NOAA's Estuarine Eutrophication Survey: Volume 3 - North Atlantic \ ME C >., Wmt i °*5 1- St. Croix River/Cobscook Bay 2- Englishman Bay 3- Narraguagus Bay 4- Blue Hill Bay rx ^ 9 5- Penobscot Bay v< 10 6- Muscongus Bay 7- Damariscotta River *"~Wl2 jtrn13 8- Sheepscot Bay 9- Kennebec/ Androscoggin Rivers 10- Casco Bay 11-Saco Bay 12- Great Bay 13- Hampton Harbor 14- Merrimack River "ifcvl5 15- Plum Island Sound 16- Massachusetts Bay 17- Boston Harbor (>N: 17 \ 18 18- Cape Cod Bay Chlorophyll a MA 4 ^K (♦JHypereutrophic (>60(ig/l) flbHigh (>20, <60ng/l) . ) ^r ]) QMedium (>5, <20jig/l) Qlow <>o<5(ig/i) North [^Unknown A nij*l**/™j Figure 4: Existing conditions for chlorophyll a, nitrogen, phosphorus, and dissolved oxygen. Symbols indicate tliat an existing condition(s) (e.g., hypereutrophic for chlorophyll a, anoxia and/or hypoxia for dissolved oxygen) was reported in at least a portion of one salinity zone of an estuary at some time during a typical annual cycle. Symbols do not necessarily represent existing conditions across an entire estuary. For a more complete review of individual estuaries, turn to the estuary summaries beginning on page 18. 11 NOAA's Estuarine Eutrophication Sun>ey: Volume 3 - North Atlantic High concentrations of phosphorus (>0.1 mg/1) were not reported in any North Atlantic estuary, while high concentrations of nitrogen (> 1.0 mg/1) occurred in small marsh creeks of Hampton Harbor and urban embayments of Cape Cod Bay. Medium concentrations of both nitrogen (> 0.1 - 1.0 mg/1) and phosphorus (> 0.01 - 0.1 mg/1) were reported as much more perva- sive, occurring over 67% of the regional area in the fall and winter. Most estuaries have not had a reported change in the concentration of either nitrogen or phosphorus be- tween 1970 and 1995. However, decreasing trends were reported in portions of Great Bay and Penobscot Bay, while the urban embayments of Cape Cod Bay were reported to have had an increase in nutrient concen- trations since 1970 (Figure 5). Nitrogen High nitrogen concentrations were reported in the tidal fresh and mixing zones of Hampton Harbor and in the urban embayments of Cape Cod Bay (2 percent of the regional estuarine area). Medium concentrations of nitrogen were reported in 13 North Atlantic estuar- ies (Figure 4). Medium concentrations were observed in up to 80 percent of the regional tidal fresh zone, in up to 53 percent of the regional mixing zone, and in up to 72 percent of the regional seawater zone. High- est concentrations of nitrogen are observed in the fall and winter in the Northern Gulf of Maine estuaries. In Southern Gulf of Maine systems, concentrations do not vary seasonally. Trends were reported as unknown for all or part of nine North Atlantic estuaries (Figure 5). Speculative increases of an unknown magnitude occurred over the last 25 years in the urban embayments of Cape Cod Bay. In addition, a speculative decrease of unknown magnitude was reported for the mixing zone of Penobscot Bay. No change in concentrations of nitro- gen occurred in all or portions of 13 estuaries. Phosphorus High phosphorus concentrations were not reported for any estuary in the North Atlantic. Medium phos- phorus concentrations were observed for 15 North At- lantic estuaries, in up to 67 percent of the seawater zone, up to 56 percent of the mixing zone, and up to 81 percent of the tidal fresh zone. Highest concentra- tions of phosphorus are observed in the fall and win- ter in the Northern Gulf of Maine estuaries. In South- em Gulf of Maine systems, concentrations do not vary seasonally. Trends in phosphorus concentrations were reported as unknown for all or portions of seven estuaries (Fig- ure 5). There were no reported changes in phospho- rus concentrations in the remaining estuaries, except for a decrease in the mixing zone of Great Bay. | Dissolved Oxygen Dissolved oxygen conditions were characterized by collecting information about existing conditions and trends for anoxia (0 mg/1), hypoxia (>0 mg/1, <2 mg/1), and biologically stressful concentrations (>2 mg/1, <5 mg/1). For each observed condition, the oc- currence, timing (both time of year and duration), fre- quency of occurrence (periodic or episodic), location in the water column (surface, bottom, or throughout), and spatial extent was recorded. The influence of wa- ter-column stratification (high, medium, low, or not a factor) on development of low dissolved oxygen was also noted. Anoxic conditions were reported in one of the 18 North Atlantic estuaries, and hypoxia was reported to occur in four estuaries. Both conditions are observed during the summer months (July to August), and while an- oxia is observed only episodically, hypoxia occurs on an annual basis. Anoxia is reported to occur through- out the water column, with a medium to high (>25% salinity zone) spatial coverage. Hypoxia is observed only in bottom waters at a very low spatial extent (0- 10% salinity zone). For both conditions, water-column stratification is not reported as a factor in the develop- ment of low dissolved oxygen. The number of estuar- ies reported as having biologically stressful concen- trations of dissolved oxygen (nine estuaries) was al- most twice the number reported as having anoxia and hypoxia (five estuaries). Biologically stressful concen- trations were reported to occur in summer in bottom waters in three estuaries, throughout the water col- umn in four estuaries, and in surface waters in one estuary. For most estuaries, biologically stressful con- centrations were reported to occur periodically over a very low spatial area; stratification was not reported as a factor in the expression of this condition. Trends for bottom-water dissolved oxygen concentra- tions were reported as unchanged in eight estuaries, increased in five estauries, and speculated to have de- creased in one estuary (Cape Cod Bay). Trends were unknown for the remaining four estuaries. Anoxia Anoxic conditions were reported to occur in the tidal fresh and mixing zones of only the Kennebec/ Androscoggin Rivers, representing a maximum of 1 percent of the total North Atlantic estuarine surface 12 NOAA's Estuarine Eutrophication Survey: Volume 3 - North Atlantic area. Where reported, anoxia is observed in July and August, on an episodic basis, and occurs throughout the water column; however, water-column stratifica- tion was not reported as a factor in the development of anoxia. The spatial extent of anoxia, when reported, is high in the tidal fresh zone (>50 percent of zone) and medium in the mixing zone (25 to 50 percent). For all or part of five estuaries (Merrimack and Damariscotta Rivers, Englishman and Muscongus Bays, and Boston Harbor), it is unknown whether an- oxia occurs. Declines in both the duration and frequency of occur- rence of anoxic events were reported for two estuar- ies, Penobscot Bay and Casco Bay. Penobscot Bay also experienced decreases in the spatial coverage of an- oxia. For more than half of the estuaries, no trends were observed, though for Muscongus Bay this assessment was speculative. Trends in spatial coverage were un- known for six estuaries, and trends in duration and frequency were unknown for seven. (Figure 5). Hypoxia Hypoxic conditions (>0 mg/1, <2 mg/1) were reported in very small areas of four estuaries; Saco Bay, Great Bay, Boston Harbor, and Cape Cod Bay. This condi- tion is observed periodically, with the exception of Saco Bay, where it is an episodic occurrence. Hypoxia is seen in the summer months, July through August, and al- most exclusively in bottom waters, though for Cape Cod Bay this assessment is speculative. The spatial extent is typically reported as very low (0 to 10 per- cent) and is observed over a total of less than 1 per- cent of the total regional estuarine surface area. For all or parts of five estuaries, it is unknown whether hy- poxia occurs. Decreases in the duration, frequency of occurrence and spatial coverage of hypoxic events were reported for two estuaries, Penobscot Bay and Casco Bay. Nine es- tuaries were reported to have no trend in duration and frequency, and 10 estuaries were reported to have no trend in spatial coverage of hypoxia. However, for Muscongus Bay, these assessments were speculative. For seven estuaries, duration and frequency of occur- rence trends were reported as unknown, and for six estuaries, trends in spatial coverage were reported as unknown. (Figure 5). Biological Stress Biologically stressful levels of dissolved oxygen (>2 mg/1, <5 mg/1) were reported to occur in all or part of 9 estuaries. This condition occurs episodically in St. Croix /Cobscook Bay, Sheepscot Bay, and Casco Bay, and periodically in Muscongus Bay, Great Bay, Hamp- ton Harbor Estuary, Plum Island Sound, Boston Har- bor and Cape Cod Bay. For Plymouth Harbor in Cape Cod Bay, biologically stressful concentrations were re- ported as persistent, but occurring over a very low (0 to 10 percent) spatial extent. The cumulative area over which it is reported accounts for a maximum of 1 per- cent of the total regional estuarine area. For less than 1 percent of the regional area, it is unknown whether this condition occurs. Biologically stressful conditions are reported to be observed from July through Sep- tember, mostly on a periodic basis. It is reported to be observed both in bottom waters and throughout the water column, but stratification was not reported to be a factor. Decreases in duration, frequency, and spatial extent were reported for Penobscot and Casco Bays. For nine estuaries, duration or spatial extent were reported as stable, and for 10 estuaries, the frequency of occurrence was reported as stable. For Muscongus Bay, assess- ments of no trend were speculative. For seven estuar- ies, trends were unknown with regard to duration and frequency, and for six estuaries, trends in spatial cov- erage were unknown (Figure 5). I Ecosystem/Community Response The responses of estuarine ecosystems to nutrient in- puts were characterized by collecting information on the status and trends of four parameters: primary pro- ductivity, pelagic and benthic communities, and sub- merged aquatic vegetation (SAV). Information regard- ing primary productivity indicated that the North At- lantic region is dominated almost exclusively by pe- lagic communities. A diverse mixture of diatoms, flagellates, and/or other plankton groups character- izes the plankton community, while the benthic com- munity is dominated by a diverse mixture of anne- lids, crustaceans, mollusks, and/or other organisms. SAV was reported in all but three of the region's estu- aries, primarily at a low or very low density. Little variation was reported for all four ecosystem param- eters throughout the region or across salinity zones. The North Atlantic region is generally stable with re- gard to changes through time (ca. 1970-95) in primary productivity and the plankton and benthic communi- ties, with shifts reported in only two estuaries. Trends in SAV coverage were reported for only 39 percent of the region; however, where information was available, an increasing coverage was reported in parts of two estuaries and a declining coverage was noted in parts of five estuaries, mostly in the seawater zone of the Southern Gulf of Maine subregion. 13 MM.-l .- Estuarme Eutwphioition Suwey: Volume 3 - North Atlantic <3 ^ %> e>c <*> ^ U} k. 5 -S 5 ■5 e aj •> St > -Si <" "2 O ~- <-> ?■ £ ^j *j a %„ X. "** %> '-V 3 \ X ^ r«& X v%, % %* P - • ••••• • ••••• -► • <--►-►-►-►-►-►-►-►-► *■ • «- -►-►-►-►-►-► -►-►-► (>. (V. O' (V. c>. o. t>. t>- • <- • ^ • II £g si £8 i| sg l| If g 2 § i < Q Z 5 5 I I E K S w z IS £8 8, sUU ES £8 I s| 11 1 |*| ij i *i §1 1 5 1; 8 O g > z E 0 5 O O O Z 3 Q 3 U tr s Q. Z 0 >- O tr < 5 g i z tr LU Q- 0. m a? I 2 ra c 1 E co 1 ■ fig CM © 14 NOAA's Estuarine Eutrophication Survey: Volume 3 - North Atlantic Primary Productivity Pelagic (plankton) communities were identified as the dominant primary producer in the mixing and /or sea- water zones of 14 estuaries, representing 83 percent of the region's estuarine surface area. A diverse mixture of pelagic and benthic communities was the next most reported group, accounting for 2 percent of the region but including 79 percent of the region's tidal fresh zone. In remaining areas, the dominant producers reported were: benthic communities in the mixing zone of Sheepscot Bay and in all of St. Croix /Cobscook Bay; SAV in parts of the mixing zone of Great Bay and the mixing zone of the Damariscotta River; and wetlands in the mixing zones of Saco Bay and Plum Island Sound. Historical shifts (ca. 1970-95) in primary productivity, i.e., shifts in dominance from one primary producer to another, were reported as unknown for one or more salinity zones in 15 estuaries (40 percent of the region's estuarine surface area). Where information was avail- able, no shifts were reported. Pelagic Community A diverse mixture of diatoms, flagellates, and /or other plankton groups dominated the plankton community in the North Atlantic region, in at least one salinity zone in 13 estuaries. Diatoms, the only other group reported, were dominant in the tidal fresh zone of Penobscot Bay. Temporal shifts in plankton dominance, from one taxo- nomic group to another, were reported as unchanged in all or parts of 12 estuaries (68 percent of the region's estuarine surface area). No information was available for the remaining area. Benthic Community The dominant benthic community (with regard to abundance) reported in the North Atlantic region was a diverse mixture of annelids, crustaceans, mollusks, and /or other benthic organisms. This community oc- curred in at least one salinity zone in 14 estuaries, rep- resenting 77 percent of the region's estuarine surface area. Annelids were the next most abundant group (re- ported in one or more salinity zones of five estuaries), followed by crustaceans (in the mixing zone of Sheepscot Bay and the seawater zone of Boston Har- bor). Two other groups reported were mollusks, in the tidal fresh and mixing zones of Penobscot Bay, and insects, in the tidal fresh zone of Sheepscot Bay. Shifts in benthic community dominance, from one taxonomic group to another, were reported in two es- tuaries during the period 1970-95. In the seawater zone of Boston Harbor, a shift from annelids to crustaceans was attributed to the cessation of sludge dumping. A shift from annelids to a diverse mixture of benthic groups was reported in parts of the seawater zone of Massachusetts Bay (Glouchester and Salem Harbors); the factors contributing to the shift were unknown. Shifts were reported as unchanged in all or parts of 13 estuaries, including 79 percent of the region's tidal fresh zone, 70 percent of the mixing zone, and 70 per- cent of the seawater zone. Submerged Aquatic Vegetation (SAV) The presence of SAV was reported in at least one sa- linity zone in 15 North Atlantic estuaries. There was no SAV reported in Hampton Harbor, and no infor- mation was available for Narraguagus and Muscongus Bays. Where reported, however, the spatial coverage of SAV (to depths of one meter below mean low wa- ter) was identified primarily as low (>10, <25 percent surface area) or very low (<10 percent surface area), equating to only 3 to 12 percent of the regional estua- rine surface area. Exceptions were a medium spatial coverage (>25, <50 percent surface area) reported for the mixing zones of Sheepscot Bay and Merrimack River, and a high spatial coverage (>50 percent sur- face area) reported for the mixing zone of the Damariscotta River, parts of the seawater zone in Casco Bay, and parts of the mixing zone in Great Bay. Historical trends in SAV coverage (ca. 1970-95) were unknown in all or part of 11 estuaries (61 percent of the region's estuarine area). Where trends were re- ported, SAV declined in parts of five estuaries (25 per- cent of the region's estuarine surface area), primarily in the Southern Gulf of Maine subregion. Declining trends were reported mostly in the seawater zone at low or medium magnitudes (0-50% change). One ex- ception was the mixing zone of the Merrimack River, where a decreasing trend of a high magnitude (>50% change) was reported. Factors reported as contribut- ing to the declines were epiphytes and disease in Bos- ton Harbor, point sources, and the physical alteration of the watershed in Massachusetts Bay Contributing factors to declines in the other estuaries were un- known. No changes in spatial coverage were reported in parts of nine estuaries. However, in two of those systems, no SAV was reported at the present time. In- creasing trends in SAV coverage were reported at a medium magnitude (>25<50 percent change) in Cobscook Bay, and at a low magnitude in parts of all salinity zones of Great Bay. In both estuaries, the in- creases were attributed to a natural cycle/cessation of disease, in addition to replanting efforts in the lower Piscataqua River section of Great Bay. 15 NOAA 's Estuanne Eutrvphicalion Survey: Volume 3 ■ North Atlantic References Beccasio, A. D., G.H. Weissberg, A.E. Redfield, R.L. Frew, W.M. Levitan, J.E. Smith, and R.E. Godwin. 1980. Atlantic Coast ecological inventory user's guide and information base. U.S. Fish and Wildlife Service, pp. 163. Boynton, W.R., W.M. Kemp, and C.W. Keefe. 1982. A comparative analysis of nutrients and other factors influencing estuarine phytoplankton production. In: V.S. Kennedy (ed.), Estuarine comparisons. New York City: Academic Press, pp. 69-90. Burkholder, J.M., KM. Mason, and H.B. Glasgow Jr. 1992a. Water-column nitrate enrichment promotes de- cline of eelgrass Zostera marina evidence from sea- sonal mesocosm experiments. Mar. Ecol. Prog. Ser. 81:163-178. Burkholder, J.M., E.J. Noga, C.H. Hobbs, and H.B. Glasgow Jr. 1992b. New "phantom" dinoflagellate is the causative agent of major estuarine fish kills. Na- ture 358:407-410. Cooper, S.R. 1995. Chesapeake Bay watershed histori- cal land use: Impacts on water quality and diatom com- munities. Ecol. App. 5(3): 703-723. Culliton, T.J., M.A. Warren, T.R. Goodspeed, D.G. Remer, CM. Blackwell, and J.D. McDonough III. 1990. 50 years of population change along the nation's coasts 1960-2010. Coastal Trends Series report no. 2. Rockville, MD: National Oceanic and Atmospheric Administra- tion, Strategic Assessment Branch. 41 p. Day, J.W. Jr., C.A.S. Hall, W.M. Kemp, and A. Yanez- Arancibia. 1989. Estuarine ecology. New York City: John Wiley and Sons. 558 p. Environmental Protection Agency (EPA). 1995. Na- tional nutrient assessment workshop proceedings. EPA 822-R-96-004. Fefer, S.I. and PA. Schettig. 1980. An ecological char- acterization of coastal Maine (North and East of Cape Elizabeth), Volume 2. FWS/OBS-80/29. Newton Cor- ner, MA: U.S. Fish and Wildlife Service. Frithsen, J.B. 1989 (draft). Marine eutrophication: Nu- trient loading, nutrient effects and the federal response. Fellow, American Association for the Advancement of Science/EPA Environmental Science and Engineering. 66 p. Garside, C, G. Hull, and C.S. Yentsch. 1978. Coastal source waters and their role as a nitrogen source for primary production in an estuary in Maine. Estuarine Interactions: 565-75. Hinga, K.R., D.W. Stanley, C.J. Klein, D.T. Lucid, and M.J. Katz (eds.). 1991. The national estuarine eutrophi- cation project: Workshop proceedings. Rockville, MD: National Oceanic and Atmospheric Administration and the University of Rhode Island Graduate School of Oceanography. 41 p. Hunt, CB. 1967. Physiography of the United States. San Francisco and London: W.H. Freeman and Com- pany, pp. 480. Jaworski, N. A. 1981 . Sources of nutrients and the scale of eutrophication problems in estuaries. In: B.J. Neilson and L.E. Cronin (eds.), Estuaries and nutrients. Clifton, NJ: Humana Press, pp. 83-110. Kemp, W.M., R.R. Twilley, J.C. Stevenson, W.R. Boynton, and J.C. Means. 1983. The decline of sub- merged vascular plants in upper Chesapeake Bay: Summary of results concerning possible causes. Mar. Tech. Soc. Journal 17(2):78-89. Likens, G.E. 1972. Nutrients and eutrophication: The limiting nutrient controversy. Proceedings of a sym- posium on nutrients and eutrophication, W.K. Kellogg Biological Station, Michigan State University, Hickory Corners, MI, Feb. 11-12, 1971. Lawrence, KS: Allen Press, Inc., for the American Society of Limnology and Oceanography, Inc. 328 p. Lowe, J. A., D.R.G. Farrow, A.S. Pait, S.J. Arenstam, and E.F. Lavan. 1991. Fish kills in coastal waters 1980-1989. Rockville, MD: NOAA Office of Ocean Resources Con- servation and Assessment, Strategic Environmental Assessments Division. 69 p. National Academy of Sciences (NAS). 1969. Eutrophi- cation: Causes, consequences, correctives. Proceedings of an international symposium on eutrophication, Uni- versity of Wisconsin, 1967. Washington, DC: NAS Printing and Publishing Office. 661 p. National Oceanic and Atmospheric Administration (NOAA). 1996. NOAA's Estuarine Eutrophication Survey. Volume 1: South Atlantic Region. Silver Spring, MD: NOAA Office of Ocean Resources Conservation and Assessment. 50 p. NOAA. 1992. Red tides: A summary of issues and ac- tivities in the United States. Rockville, MD: NOAA Of- fice of Ocean Resources Conservation and Assessment. 23 p. 16 NOAA's Estuarine Eutrophication Survey: Volume 3 - North Atlantic NO A A. 1991. Nutrient-enhanced coastal ocean pro- ductivity. Proceedings of a workshop, Louisiana Uni- versities Marine Consortium, October 1991. Held in conjunction with NOAA Coastal Ocean Program Of- fice. TAMU-SG-92-109. Galveston, TX: Texas A&M University Sea Grant Program, pp. 150-153. NOAA. 1989. Susceptibility and status of East Coast estuaries to nutrient discharges: Albemarle /Pamlico Sound to Biscayne Bay. Rockville, MD: NOAA Office of Ocean Resources Conservation and Assessment. 31 p. Nixon, S.W. 1995. Coastal marine eutrophication: A definition, social causes, and future concerns. Ophelia 41:199-219. Ryther, J.H. and W.N. Dunstan. 1971. Nitrogen and eutrophication in the coastal marine environment. Sci- ence 171:1008-1013. Smayda, T.J. 1989. Primary production and the global epidemic of phytoplankton blooms in the sea: A link- age? In: E.M. Cosper, V.M. Bricelj, and E.J. Carpenter (eds.), Novel phytoplankton blooms: Causes and ef- fects of recurrent brown tides and other unusual blooms. Coastal and Estuarine Series 35. Berlin: Springer- Verlag. pp. 449-483. Stevenson, J.C, L.W. Staver, and K.W. Staver. 1993. Wa- ter quality associated with survival of submerged aquatic vegetation along an estuarine gradient. Estu- aries 16(2):346-361. Nixon, S.W. 1983. Estuarine ecology: A comparative and experimental analysis using 14 estuaries and the MERL mesocosms. Final report to the U.S. Environ- mental Protection Agency, Chesapeake Bay Program, Grant No. X-003259-01. April 1993. Nixon, S.W., CD. Hunt, and B.N. Nowicki. 1986. The retention of nutrients (C,N,P), heavy metals (Mn, Cd, Pb, Cu), and petroleum hydrocarbons in Narragansett Bay. In: P. Lasserre and J.M. Martin (eds.), Bio- geochemical processes at the land-sea boundary. Amsterdam: Elsevier Press, pp. 99-122. Orth, R.J. and K.A. Moore. 1984. Distribution and abundance of submerged aquatic vegetation in Chesa- peake Bay: An historical perspective. Estuaries 7:531- 540. Paerl, H.W. 1988. Nuisance phytoplankton blooms in coastal, estuarine and inland waters. Limnology and Oceanography 33:823-847. Rabalais, N.N. 1992. An updated summary of status and trends in indicators of nutrient enrichment in the Gulf of Mexico. Prepared for the Gulf of Mexico Pro- gram, Technical Steering Committee, Nutrient Sub- committee, Stennis Space Center, MS. Publication No. EPA/800-R-92-004. 421 p. Rabalais, N.N. and D.E. Harper Jr. 1992. Studies of benthic biota in areas affected by moderate and severe hypoxia. In: Nutrient-enhanced coastal ocean pro- ductivity. Proceedings of a workshop, Louisiana Uni- versities Marine Consortium, October 1991. Held in conjunction with NOAA Coastal Ocean Program Of- fice. TAMU-SG-92-109. Galveston, TX: Texas A&M University Sea Grant Program, pp. 150-153. Whitledge, T.E. 1985. Nationwide review of oxygen depletion and eutrophication in estuarine and coastal waters: Executive summary. (Completion report sub- mitted to U.S. Dept. of Commerce.) Rockville, MD: NOAA, NOS. 28 p. Whitledge, T.E. and W.M. Pulich Jr. 1991. Report of the brown tide symposium and workshop, July 15-16, 1991. Port Aransas, TX: University of Texas Marine Science Institute. 44 p. 17 Estuary Summaries This section presents one-page summaries on the status and trends ofeutrophication conditions for the 18 North Atlantic estuaries. The summary information is organized into four sections: algal conditions, nutrients, dissolved oxygen, and ecosystem/community responses. Each page also includes a salinity map depicting the spatial framework for which survey information was collected, selected physical and hydrologic characteristics, and a narrative overview of the survey infor- mation. Salinity Maps. Salinity maps depict the estuary extent, salinity zones, and subareas within the salinity zones. Salinity zones are divided into tidal fresh (0.0-0.5 ppt), mixing (0.5-25.0 ppt), and seawater ( >25.0 ppt) based on average annual salinity found throughout the water column. Subareas were identified by survey partici- pants as regions that were either better understood than the rest of a salinity zone, or that behaved differently, or both. Each map also has an inset showing the location of the estuary and its estuarine drainage area (EDA) (see below). Physical and Hydrologic Data. Physical and hydrologic characteristics data are included so that readers can better understand the survey results and make meaningful comparisons among the estuaries. The EDA is the land and water component of a watershed that drains into and most directly affects estuarine waters. The average daily inflow is the estimated discharge of freshwater into the estuary. Surface area includes the area from the head of tide to the boundary with other water bodies. Average depth is the mean depth from mid-tide level. Volume is the product of the surface area and the average depth. Survey Results. Selected data are presented in a unique format that is intended to highlight survey results for each estuary. The existing conditions symbols represent either the maximum conditions predominating one or more months in a typical year, or whether there are resource impacts due to bloom events. The trends (circa 1970-1995 unless otherwise stated) symbols indicate either the direction and magnitude of change in concen- trations, or in the frequency of occurrence. The four sections on each page include a text block to highlight additional information such as probable months of occurrence and periodicity for each parameter, limiting factors to algal biomass, nuisance and toxic algal species, nutrient forms, and degree of water-column stratification. Some parameters are not characterized by symbols on the estuary pages. These include macroalgal and epi- phyte abundance, biological stress, minimum average monthly bottom dissolved oxygen trends, temporal shifts in primary productivity, benthic community shifts, intertidal wetlands, and planktonic community shifts. These parameters are described in the Regional Overview section (starting on page 6) and, where relevant, are highlighted in the text blocks under each parameter section on the estuary pages. See the next page for a key that explains the symbols used on the summary pages. See Table 1 on page 3 for complete details about the characteristics of each parameter. page 29 30 31 32 33 34 35 36 37 Estuary page Estuary St. Croix River/Cobscook Bay 20 Casco Bay Englishman Bay 21 Saco Bay Narraguagus Bay 22 Great Bay Blue Hill Bay 23 Hampton Harbor Penobscot Bay 24 Merrimack River Muscongus Bay 25 Plum Island Sound Damariscotta River 26 Massachusetts Bay Sheepscot Bay 27 Boston Harbor Kennebec / And roscoggin Rivers 28 Cape Cod Bay 18 NOAA's Estuarine Eutrophication Survey: Volume 3 - North Atlantic Key to Symbols Used on Estuary Summaries Tidal Fresh Mixing M 25-50% +\ Seawater Subarea X Subarea Y M 50-100% 1> L & Salinity Zone Absent: if the salinity zone is not present in the estuary the entire box is left blank Spatial Coverage: surface area over which condition occurs (not listed for nuisance/toxic algae or low/not observed conditions) Reliability: indicates assessment made from speculative inferences Salinity Zone Divided: salinity zones are often divided into subareas to account for unique characteristics H 50-100% Existing Conditions Trends (circa 1970-1995) Concentrations (Chi a, Turbidity, Nutrients, SAV) E hypereutrophic chl-a: >60 ug/l H hi9h chl-a: >20, _<60 ug/l turbidity: secchi <1m TDN: >1 mg/1 TDP:^0.1 mg/l SAV >50, £100 % coverage |\/| medium chl-a: >5, <20 ug/l turbidity: secchi j>1 m, <3m TDN:>0.1,<1 mg/l TDP:>0.01, <0.1 mg/l SAV >25, < 50 % coverage |_ low chl-a: >0, <5_ug/l turbidity: secchi >3m TDN: >0, <0.1 mg/l TDP: >0, <0.01 mg/l SAV >10, < 25 % coverage y|_ very low SAV >0, _<1 0 % coverage N§ no SAV in zone g blackwater area 9 unknown Event Occurrences (Nuisance/Toxic Algae, d.o.) Y impacts on resources nuisance algae: impacts occur toxic algae: impacts occur or low d.o. is observed anoxia: 0 mg/l hypoxia: >0, <2 mg/l N no resource impacts no nuisance algae impacts no toxic algae impacts or low d.o. not observed no anoxic events no hypoxic events *> unknown Direction of Change Magnitude of Change (Concentrations or Frequency of Event Occurrences) *^K increase "^K ni9n no trend 9 unknown >50%, <100% decrease <> medium U >25%. <50% y\ low >0%, <25% /9\, magnitude unknown 19 NOAA's Estuanne Eutrophication Sun*ey: Volume 3 - North Atlantic St. Croix River/Cobscook Bay Salinity Zones Algal Conditions Tidal Fresh Mixing M N N I r Seawater SI Croix Rival Cobscook Bay L ? ■ ... M iO-IOOS" 9 ■ M 50-10014 N N Y — Y — Highest turbidity occurs episodically throughout the year in the mixing zone and in late fall in the seawater zone due to wind, dredging, and resuspension. A decrease in turbidity is attributed to a decrease in paper mill effluent. Toxic Alexandrium spp. and Pseudonitzchia spp. occur periodically in summer in subareas of the seawater zone Ecosystem/Community Responses s dal FfMh M ring S«awater St Crott Rfvw Coteoook Bay NS ---] NS 9 ■ VL /\ Primary productivity is dominated by the benthic community Planlctonic community is a diverse mixture throughout the seawater zone SAV increase in Cobscook Bay is attributed to disappearance of wasting disease. St. Croix River/Cobscook Bay, chlorophyll a concentrations are low and turbidity concentrations are medium. There are no biological resource impacts due to nuisance algae blooms, but toxic algal blooms occur in the seawater zone. Nitrogen and phosphorus concentrations are reported as medium throughout the estuary, and there are no reported observa- tions of anoxia or hypoxia. In Cobscook Bay, SAV spatial coverage is very low. Most conditions were stable with the exception of a decrease in turbidity in the mixing zone, and an increase in SAV in Cobscook Bay. Trends were unknown in the St. Croix River for chlorophyll a, turbidity, anoxia, hypoxia, and SAV. Physical and Hydrologic Characteristics Estuarine Drainage Area (mP) n/a Avg. Daily Inflow (cts) 2,850 Estuary Tidal Fresh Mixing Seawater Surface Area (mi1) 63.3 2.5 St. Croix_River Cobscook Bay 24.7 36.1 Average Depth (it) 72.0 40.0 72.8 26 Volume (billion cu It) 127 2.7 123.4 26.1 A complex estuary consisting of bays and interconnecting channels. The northern part of the bay is shallow and gently sloping while the more southern reaches are much steeper. Freshwater inflow from the St. Croix is minimal compared to the tides, therefore circulation is dominated by intense tidal exchange. Gulf of Maine salinities occur throughout the estuary due to tidal influence. The system is well mixed with a tidal range of approximately 18 ft throughout the main bay area ( 18.2 ft near Eastport). Nutrients Tidal Fresh Mixing M M Seawater Cobscook Bay M M 50-100% M 50-100% M 50-100% Maximum concentrations occur from October through March. Dissolved Oxygen Tidal Fresh Mixing Seawater St Crax River Cobscook Bay N ■ N 9 ■ N N 9 ■ N 9 ■ N Biological stress is speculated to occur on bottom in Cobscook Bay episodically in association with Salmon enclosures from July through September. High magnitude increase of bottom dissolved oxygen in mixing zone occurred 1970-1995. 20 Key on page 19 NOAA's Estuarine Eutrophication Survey: Volume 3 - North Atlantic Englishman Bay Salinity Zones Q Tidal Fresh ■ Mixing Zone fj Seawater Zone Machias Chmndhr Rlvr Algal Conditions Tidal Fresh 'Tidal Fresh area not characterized tor this estuary Mixing Seawater M tf N Ch]-fl maximums and toxic Alexandrium spp. occur periodically. Ecosystem/Community Responses Tidal Fresh Mixing Seawater c NS 9 ■ VL 9 ■ Primary productivity is dominated by the pelagic community. Planktonic community is a diverse mixture in the seawater zone; benthic community is predominantly annelids in the mixing zone. In Englishman Bay, with the exception of SAV, all of the re- sponses for the mixing zone are unknown. In the seawater zone, chlorophyll a concentrations are medium and turbid- ity concentrations are low. There is no impact on biological resources due to nuisance algal blooms, but impacts occur due to toxic algal blooms. Nitrogen concentrations are me- dium and phosphorus concentrations are unknown. There are no observations of anoxia or hypoxia. SAV is not present in the mixing zone, and is present at a very low spatial cov- erage in the seawater zone. Most trends were unknown with the exception of an increase in turbidity, and no change in toxic algal bloom occurrences or nitrogen concentrations. Physical and Hydrologic Characteristics Estuarine Drainage Area (mi2) 1,017 Avg. Daily Inflow (cfs) 1,600 Estuary Tidal Fresh Mixing Seawater Surface Area (m?) 86.7 1.6 85.1 Average Depth (it) 41.5 11.8 42.1 Volume (bUlion cu tt) 100.4 0.5 99.9 Consists of Englishman Bay, Machias Bay and several smaller embayments. Receives majority of freshwater from the Machias and East Machias Rivers. Most salinity variations occur within the upper reaches of the estuary. Circulation is affected largely by tidal mixing and nontidal currents. Considered to be a well mixed estuary with rapid flushing. Tidal range is 12.1 ft near the mouth of Great Cove. Nutrients Tidal Fresh Mixing Seawater 9 ■ 9 ■ M •> 9 ■ 9 ■ 9 II* ■ II " Medium concentrations occur July through September. Dissolved Oxygen Tidal Fresh Mixing Seawater (h 9 ■ 9 ■ N ■ 9 ■ 9 ■ 'nII* Key on page 19 21 NOAA $ Estuanne Eutrophtcation Sunvy: Volume 3 - North Atlantic Narraguagus Bay Addison Harrington Algal Conditions Tidal Fresh Mixing 'Tidal Fresh area not characterized lor this estuary M N Seawater N ChJ-o maximums occur periodically July through September with light as the limiting factor. Toxic Aexandrium spp. occurs in the mixing zone, and periodically in summer in seawater zone. Ecosystem/Community Responses TKJaJ Freeh Mbdng Seawater ■ 9 ■ 9 ■ 9 ■ 9 ■ In Narraguagus Bay, chlorophyll a concentrations are me- dium in both zones, and turbidity is unknown in the mixing zone and low in the seawater zone. There are no biological resource impacts due to nuisance algal blooms, but toxic al- gal blooms occur. Nitrogen and phosphorus concentrations are unknown, and there are no observations of anoxia or hypoxia. SAV spatial coverage is also unknown. Trends throughout the entire estuary are unknown. Physical and Hydrologic Characteristics Estuarine Drainage Area (mi2) 1,131 Avg. Daily Inflow (cfs) 900 Estuary Tidal Fresh Mixing Seawater Surface Area (m?) 79.3 1.5 77.8 Average Depth (it) 34.0 10.6 34.5 Volume (bfllbn cu It) 75.2 0.4 74.8 Consists of Narraguagus Bay, Western Bay and several smaller embayments. Receives majority of freshwater from the Narraguagus and Pleasant Rivers. Most salinity variations occur within the upper reaches of the estuary. Circulation affected largely by tidal mixing and nontidal currents. Is well mixed with rapid flushing. Tidal range is 11.1 ft near the mouth of Pleasant River. Nutrients Tidal Fresh Mixing Seawater 9 ■ 9 ■ 9 ■ 9 ■ 9 ■ 9 ■ 9 ■ 9 ■ Dissolved Oxygen Tidal Fresh Mix.ng Seawater N 9 ■ N 9 ■ N 9 ■ N 9 ■ 22 Key on page 19 NOAA's Estuarine Eutrophication Survey: Volume 3 - North Atlantic Blue Hill Q Tidal Fresh ■ Mixing Zone O Seawater Zone Algal Conditions Tidal Fresh Tidal Fresh area not characterized tor this estuary Mixing M N Seawater M N Highest turbidity speculated to occur persistently throughout the year. Toxic Alexandrium spp. occurs episodically in summer. Ecosystem/Community Responses Tidal Fresh Mixing Seawater \ VL • VL • Primary productivity is dominated by the pelagic community. In the seawater zone, planktonic and benthic communities are a diverse mixture. In Blue Hill Bay, chlorophyll a concentrations are unknown in the mixing zone and medium in the seawater zone, and turbidity concentrations are medium in the mixing zone and low in the seawater zone. There are no known impacts on biological resources from nuisance algal blooms, but there are impacts in the seawater zone due to toxic algal blooms. Nitrogen and phosphorus concentrations are medium throughout the estuary, and there are no observations of anoxia or hypoxia. SAV spatial coverage is speculated to be very low in both the mixing and seawater zones. Trends were unknown for algal conditions in the mixing zone. For most of the remaining parameters, in both the mixing and seawater zones, no changes occurred. Physical and Hydrologic Characteristics Estuarine Drainage Area (m&) 880 Avg. Daily Inflow (els) 1,300 Estuary Tidal Fresh Mixing Seawater Surface Area (m?) 121.9 0.8 121.1 Average Depth /to 76.7 42.1 77.0 Volume (billion cu ft) 260.9 0.9 260 Consists of Union River Bay, Blue Hill Bay and smaller embayments. Receives majority of freshwater from Union River. Gulf of Maine salinities exist throughout much of the estuary. Within the narrow, upper portion of Union River Bay, vertical stratification of salinities may exist all year. Circulation is affected largely by tidal and nontidal currents. Tidal range is approximately 10 ft near the mouth of Union River. Nutrients Tidal Fresh Mixing Seawater M 50-100% M 50-100N M 50-100*. M 50-100N Medium concentrations occur October through March. Dissolved Oxygen Tidal Fresh Mixing Seawate' N [n" N In Key on page 19 :; NOAA's Estuanne Eutrophicatton Survey: Volume 3 - North Atlantic Penobscot Bay Salinity Zones □ lid*] Fresh | Mixing Zone Q Seawater Zone Rockland Algal Conditions Tidal Fresh Mixing Seawater 1 L 9 ■ L 9 ■ L 9 ■ M 50-100% 9 ■ M 50-100% 9 ■ L 9 ■ l? 9 ■ N N \h\ 9 9 I " II " I i N Nitrogen is the limiting factor for chl-a in the seawater zone. Highest turbidity occurs persistently throughout the year. Ecosystem/Community Responses Tktol Fresh Mixing Seawater |nsit] L 9 ■ L 9 ■ Primary productivity is dominated by the pelagic community. Flanktonic community is predominantly diatoms in the tidal fresh zone, and a diverse mixture in the mixing and seawater zones. Benthic community is dominated by mollusks in the tidal fresh and mixing zones, and is diverse in the seawater zone. In Penobscot Bay, chlorophyll a concentrations are low in all salinity zones, and turbidity concentrations are medium in the tidal fresh and mixing zones, and low in the seawater zone. Biological resource impacts from nuisance or toxic al- gal blooms are unknown in the tidal fresh zone, and do not occur in the mixing and seawater zones. Nitrogen and phos- phorus concentrations are low throughout the estuary. There were no observations of anoxia or hypoxia reported. There is no SAV in the tidal fresh zone, andlow spatial coverage in the rest of the estuary. Most of the trends were either unknown or stable. How- ever, there were decreases in nitrogen concentrations (specu- lative) in the mixing zone, and decreases in both anoxia and hypoxia in the tidal fresh and mixing zones. SAV trends are unknown. Physical and Hydrologic Characteristics Estuarine Drainage Area (mi2) 3,160 Avg. Daily Inflow (cfs) 16,100 Estuary Tidal Fresh Mixing Seawater Surface Area (mP) 387.0 0.5 13.1 367.1 Average Depth (tt) 70.1 19.5 31.0 75.1 Volume (bUBon cu ft) 755.3 0.3 11.3 743.7 Consists of Penobscot Bay with several islands interspersed throughout the estuary. Seaward boundary is difficult to define. High salinities can occur in upper reaches of the Bay. Receives majority of freshwater from Penobscot River. During periods of high flow, vertical stratification is very apparent. Lower flow periods exhibit moderate salinity stratification. Tidal range is 9.6 ft near Rockland. Nutrients Tidal Fresh Mixing Seawater I L 9 ■ L * L * L L L Dissolved Oxygen Tidal Fresh Mixing Seawaler \K 4- N 4- N N I 4- n][T N High magnitude increase in bottom dissolved oxygen concentrations occurred 1970-1990. All trends attributed to point source changes. 24 Key on page 19 NOAA's Estuarine Eutrophication Survey: Volume 3 - North Atlantic Muscongus Bay 0 Tidal Fresh ■ Mixing Zone D Sea water Zone Algal Conditions J Tidal Fresh Mixing Seawaler Ej] 'Tidal Fresh BjS area not fcj characterized B^l /or fh/s estuary Medomak River St George River 9 ■ 9 ■ M 5O-10O% 9 ■ 50-100% I 9 ■ 9 ■ 9 ■ 9 ■ 9 ■ 9 ■ I N 9 ■ N 9 ■ N 9 ■ | N 9 ■ N 9 ■ Y 9 ■ Chl-o maximums occur periodically June through August in the mixing zone, and in March-April and August-September in the seawater zone. Toxic Alexandrium spp. occurs episodically in summer. Ecosystem/Community Responses j Tidal Fresh Mixing Seawater r Medomak River St. George River 9 ■ 9 ■ 9 ■ 9 ■ 9 ■ 9 ■ Primary productivity is dominated by the pelagic community. Benthic community is speculated to be a diverse mixture. In Muscongus Bay, chlorophyll a concentrations are medium and turbidity concentrations are unknown. There are no bio- logical resource impacts from nuisance algal blooms, but there are impacts from toxic algal blooms in the seawater zone. Nitrogen and phosphorus concentrations are medium. There are no observations of either anoxia or hypoxia. Trends are unknown with the exception of stable conditions reported in the seawater zone for chlorophyll a, nitrogen and phosphorus, and in the mixing zone for anoxia and hypoxia. SAV spatial coverage and trends are unknown. Physical and Hydrologic Characteristics Estuarine Drainage Area (mi2) 346 Avg. Daily Inflow (cfs) 600 Estuary Tidal Fresh Mixing Seawater Surface Area (mi2) 77.8 M<*V>T.*k R SI G«o^« P 1.1 1.3 75.4 Average Depth m 45.7 6.7 7.9 46.9 Volume (billion cu It) 99.1 0.2 0.3 98.6 Consists of Muscongus Bay with several small islands. Receives minimal freshwater inflow from the Medomak and St. George Rivers. Most salinity variations occur within the upper reaches of the estuary. Circulation affected largely by tidal exchange and nontidal currents. Tidal range is 8.8 ft near the Georges Islands. Nutrients Tidal Fresh Mixing Seawater Medomak River St George Rrver 9 ■ 9 ■ JVL SO-10O% 9 ■ M 50-100% 5 9 ■ ■ M SO 100% ■ M 50-100% Conditions occur all year in St. George River and from October through March in seawater. Dissolved Oxygen Tidal Fresh M.xmg Seawater j Medomak Rivef St George River 9 ■ 9 ■ N • N 9 ■ 9 ■ 9 ■ N • N 9 ■ A high spatial extent of biological stress is observed periodically July through August throughout the water column in the Medomak River. Key on page 19 25 NOAA's Estuannt Eutrvphiariwn Suney: Volume 3 - North Atlantic Saco Bay r-i W 4/ }" "*> \+ Ltt, / Cape S Elizabeth V ■a Shaft Pine Point ^3 C / •♦ / °u / Saco .Cataract Dam Saco.l^-^ \ c •^^•/vS^X / 0 1.25 Salinity Zones 2.5 0 Tidal Fresh ■ Mixing Zone □ Seawater Zone / Miles Algal Conditions Tidal Fresh Mixing Seawater L L M 5O100N 9 ■ L 9 ■ N 2J]E^ Y Y Ecosystem/Community Responses Tidal Freth Mixing Seawater s VL ■ NS 9 ■ Primary productivity is dominated by wetlands in the mixing zone and by the pelagic community in the seawater zone. In Saco Bay, chlorophyll a concentrations are low, and tur- bidity concentrations range from low to medium. Nuisance algal blooms have not impacted biological resources, how- ever toxic algal blooms have. Nitrogen and phosphorus con- centrations are medium in the mixing zone and low in the seawater zone. There are no observations of anoxia, but hy- poxia was observed in the seawater zone. SAV spatial cov- erage is either very low or nonexistent Trends were stable for most parameters. However, trends were unknown for turbidity, dissolved oxygen, and SAV. Physical and Hydrologic Characteristics Estuarine Drainage Area (mi2) 1,787 Avg. Daily Inflow (cfs) 3,600 Estuary Tidal Fresh Mixing Seawater Surface Area (ml2) 19.0 1.0 18.0 Average Depth m 35.3 10.2 36.7 Volume (blllton cu ft) 18.7 0.3 18.4 A highly stratified, saltwedge-type of estuary. Freshwater inflow is dominated by the Saco River. Salinity stratification is more pronounced during periods of high freshwater inflow. The estuary begins below the Cataract Dam on the Saco River. Tidal range is 8.6 ft near the mouth of the estuary. Nutrients Tidal Fresh Mixing Seawater M L 50-100% M L 50-100% Maximum concentrations occur from December through March. Dissolved Oxygen Tidal Fresh Mixing Seawater 7T] 9 ■ N 9 ■ N 9 ■ 0 10-A 9 ■ Hypoxia occurs in seawater bottom water episodically in August. Since 1970 there has been a high magnitude increase in bottom dissolved oxygen concentrations in Saco River, attributed to changes in point sources. ' 30 Key on page 19 NOAA's Estuarine Eutrophication Survey: Volume 3 - North Atlantic Great Bay V Tidal Dam f fiwh Cr—kd Coehtoo \ ff/nr V m TWal^A*. Dam >&> Sa/mon k F»M» " R/vw fa ■ * ■ ~ 3) ( m 3 . A TWal .-^Oytmr r7/wr%£ Dam7 ' r^* — *>— Spinney p^ v »! Croafc ' N^O-^-. &rs_ Tidal (**"A Portsmouth ^"^fcc $$y~ NewmarkefNa*^ K Sagamore Creek (No Data) \/ V North t y Guit / ot 1 Ualno Salinity Zones TV* Dam / 0 U5 2.5 Q Tidal Fresh ■ Mixing Zone HJ Seawater Zone Miles Algal Conditions Mixing Piscataqua/ Great Bay/ Oyster Salmon Falls/ Lamprey RJ River Cocheco R. Squamscott R. Spruce Creek H M M M M 25-50% 9 ■ M M 9 9 ■ ■ Y N — N — N 9 ■ N — N ... N — N — Seawater M? 9 9 ■ a N — Y N ... Y ? In mixing zone, chl- M 9 ■ Primary productivity driven by pelagic and benthic mixture. Pelagic and benthic communities are diverse. SAV increase in mixing and seawater zones is attributed to natural cycle and some replanting in seawater zone. In Great Bay, chlorophyll a concentrations range from low to high andturbidity from low to medium. Nuisance and toxic algal blooms have an impact on biological resources in subareas of the mixing and seawater zones. Nitrogen and phosphorus concentrations are medium. There are no ob- servations of anoxia, however hypoxia is reported in small subarea of the mixing zone. SAV coverage ranges from very low to high. Most trends were stable, except an increase in SAV spatial coverage in subareas of both salinity zones and a decrease in phosphorus concentrations in a subarea of the mixing zone. Physical and Hydrologic Characteristics __ Estuarine Drainage Area (mP) 997 Avg. Daily Inflow (cfs) 2,000 Estuary Mixing Seawater Surface Area tmf) 20.8 Piacatagua/ Great BaW Ovate* Sprue* Salmon FaJle/ Lamprey H./ R/ver Craa* Cocheco R. Squameoon R. 2.5 7.3 0.3 0.4 In Sf»v»ir General :•— . 10.1 0.2 Average Depth (tt) 11.4 n/a n/a n/a n/a n/a n/a Volume (bilSon cu tt) 6.6 n/a n/a n/a n/a n/a n/a Consists of Great Bay, Little Bay, Piscataqua River and several smaller coastal streams and rivers. Upper broad section of estuary is shallow while lower seawater section can reach depths over 80 ft. Well mixed estuary due to tidal velocity and height, as well as estuary geometry. Moderate stratification occurs during high flow periods. Tidal range is approximately 9 ft near Portsmouth. Nutrients Mixing Piscataqua/ Great Bay/ Oyster Spruce Salmon Falls/ Lamprey HJ River Creek Cocheco R Squamscott R M M M M M 50 1 00*. ... M Fftuanne Eutrophicatwn Surrey: Volume 3 - North Atlantic Hampton Harbor f. ^X^/*""^\ Hampton Rfvwr M ** s^ Ok Hampton Falls L/ ^ — ^nT^^C^ \ O fj \. ) Gu/r * A" Hvrpun f of \ /o^smttor \ Maine Brown* r*C\ rV { Salinity Zones 3 \ North Q Tidal Fresh | Mixing Zone □ Sea water Zone \ f \ 9 o as o.$ \ Milr. Algal Conditions Tidal Fresh Mixing M N N — Seawaler M N N ChJ-a maximums occur periodically in summer in the mixing and seawater zones, with nitrogen as the limiting factor in the seawater zone. Ecosystem/Community Responses ! TkW Fresh Mixing Seawaler NS — NS — Primary productivity is dominated by both pelagic and benthic communities in the mixing and seawater zones. Benthic community is diverse. In Hampton Harbor, chlorophyll a concentrations are me- dium and turbidity concentrations are unknown. There are no biological resource impacts from nuisance or toxic algal blooms. Nitrogen concentrations range from medium to high, and phosphorus concentrations are medium. There are no observations of anoxia or hypoxia. SAV is not present. Stable trends were reported for nuisance and toxic algal blooms and SAV spatial coverage. All other trends were unknown. Physical and Hydrologic Characteristics Estuary Tidal Fresh Mixing Seawater Surface Area (mP) 1.5 0.6 0.9 Average Depth m n/a n/a n/a Volume (billion cu It) n/a n/a n/a A small, very shallow system consisting of several small coastal streams and rivers. Most of the surrounding area is made up of extensive salt marshes and tidal flats. Shallowness, rapid flushing, and limited freshwater inflow contribute to it being a well mixed estuary. Tidal range is approximately 9 ft near Hampton Harbor. Nutrients Tidal Fresh Mixing Seawater 1 H 9 ■ M 9 ■ 0-10% 10-25% ■a M 9 ■ 50-100** 9 ■ 50-100% Reported nutrient concentrations occur throughout the year. Dissolved Oxygen Tidal Fresh Mixing Seawater N 9 N ■ N 9 ■ N 9 ■ Biological stress is observed over a small spatial extent of the mixing zone episodically from July through October. 32 Key on page 19 NOAA's Estuarine Eutrophication Survey: Volume 3 - North Atlantic Merrimack River Gulf of Maine North 1.2S 2.5 Miles Algal Conditions Tidal Fresh 9 9 ■ ■ Mixing L Salinity Zones Q Tidal Fresh ■ Mixing Zone □ SeawaterZone Seawater Ecosystem/Community Responses Tidal Fresh Mixing Seawater 9 ■ 9 ■ M \ 1 In the Merrimack River, every parameter is unknown ex- cept for SAV spatial coverage, which is medium in the mix- ing zone and has decreased Dy a high magnitude since 1 970. Physical and Hydrologic Characteristics Estuarine Drainage Area (mi2) 2,313 Avg. Daily Inflow (cfs) 8,400 Estuary Tidal Fresh Mixing Seawater Surface Area (mi2) 6.7 3.3 3.4 Average Depth (ft) 11.8 13.2 10.1 Volume (billion cu It) 2.2 1.2 1.0 Shallow, riverine, salt-wedge estuary. Salinities tend to be moderately to highly stratified throughout the year. Freshwater inflow is dominated by the Merrimack River. Tidal range is 8.2 ft near the mouth of the estuary. Nutrients Tidal Fresh Mixing Seawater 9 ■ 9 ■ 9 ■ 9 ■ 9 ■ 9 ■ 9 ■ 9 ■ Dissolved Oxygen Tidal Fresh Mixing Seawaier El 9 9 ■ 9 ■ 9 ■ 9 ■ |_ 9 ■ 9 ■ 9 ■ Key on page 19 33 NOAA's Estuarine Eutrvphicatton Survey: Volume 3 - North Atlantic Plum Island Sound ^"\. \ f Merrimack V *\M Plum ^ \ Ulmnd JJ \ r -T Sutf rfL_ Parker River w* ol Maine flotnay JZ.J bland fUy Sound flpwwlch /^ Iptwlch.^ NortA D,m I ♦ J 0 L2S 2.5 ^ 5 ?fe?> Salinity Zones 0 Tidal Fresh \ ■ Mixing Zone . D SeawaterZone Miles Jt Algal Conditions Tidal Fresh Mixing H Seawater H ?5-50% N N M — N N Chl-o maximums occur periodicaUy in summer in the mixing zone and in winter in the seawater zone, with limiting factors of light and nitrogen for both zones. Highest turbidity occurs throughout the year. Ecosystem/Community Responses T• yLsv \ f tr^ Massachusetts \ L \ B*^ \ $ tf~X Boaton\ * Boston N&ponsel ^6C M j-flrf-^Js , North 0 4 8 Miles Algal Conditions Tidal Fresh Mixing Seawater M 50-100% ... I ... N Y — Chl-a maximums occur periodically in fall in the mixing zone and in winter in the seawater zone, with a limiting factor of nitrogen for both zones. Nuisance Phaeocystis spp. is present, but speculated not to be a problem to biological resources. Toxic Alexandrium spp. blooms occur periodically in summer. Ecosystem/Community Responses Tidal Fresh Mixing Seawater n VL 0 Primary productivity is dominated by the pelagic community. Planktonic and benthic communities are a diverse mixture, except in urban areas where the benthic community is dominated by annelids. The decrease in SAV is attributed to increased point sources and physical alterations to the watershed. In Massachusetts Bay, chlorophyll a concentrations are me- dium and turbidity concentrations are low. Nuisance algal blooms do not have an impact on biological resources, but toxic algal blooms do occur. Nitrogen and phosphorus con- centrations are medium. There are no occurrences of anoxia or hypoxia. SAV spatial coverage is very low. All of the conditions have been stable, except SAV coverage which has slightly declined. Physical and Hydrologic Characteristics Estuarine Drainage Area (mi2) 1,197 Avg. Daily Inflow (cfs) 2,900 Estuary Tidal Fresh Mixing Seawater Surface Area (mi2) 297 297 Average Depth (it) 89.5 89.5 Volume (billon cu ft) 741 741 A large coastal bay with smaller coastal embayments. Gulf of Maine salinities exist within the main bay. Circulation is strongly influenced by tidas and nontidal surface currents. Tidal range is approximately 9 ft near Beverly Harbor. Nutrients Tidal Fresh Mixing Seawater M 50-100% M 50- 100*. Medium concentrations occur all year. Dissolved Oxygen Tidal Fresh Mixing Seawater j N 1 N — ! Key on page 19 35 NOAA s Estuanne Eutroplucatton Survey: Volume 3 - North Atlantic Boston Harbor j^V 1 r / X Jjj/ Mito ) — , ,p - 1 Massachusetts Bay €*v Boston «_ /nrw ry Harbor IS Boston Harbor • Ji Boslon v V — fn f ^ /I 8*y \ \ mpwn Mar k_ /^ OiAicy W^ S Bay . c4 HinghvnBiy ^f~/)^ «•/ 0 North *"V**^ t 2.5 Salinity Zones 0 Tidal Fresh ■ Mixing Zone O Seawater Zone Miles Algal Conditions Tidal Fr»sh Mbdnfl M 50 10ON 9 ■ M 5C 100% N ? Seawater Boslon Inn* Hirbor Boslon Hsrbor M SO 100-..- M 50-100% M 50-1 0O%- • M 50-100% N 9 ■ N 9 ■ N ? N 9 ■ N 9 ■ Ch]-ey: Volume 3 - North Atlantic Muscongus Bay Seth Barker* Lee Doggett* Paul Mitnik* John Sowles* Damariscotta River Seth Barker* Lee Doggett* Chris Garside* Peter Larsen* Theodore Loder* Bernard McAlice Lawrence Mayer* Paul Mitnik* Byard Mosher* Carter Newell John Sowles* David Townsend Robert Vadas Sheepscot Bay Arnold Banner* Seth Barker* Lee Doggett* Chris Garside* Peter Larsen* Theodore Loder* Bernard McAlice Lawrence Mayer* Paul Mitnik* Byard Mosher* John Sowles* Robert Vadas Maine Dept. of Marine Res. Casco Bay Estuary Project Maine DEP Maine DEP Maine Dept. of Marine Res. Casco Bay Estuary Project Bigelow Laboratory Bigelow Laboratory University of New Hampshire Bigelow Laboratory Darling Marine Center - UNH Maine DEP University of New Hampshire Great Eastern Mussel Farm Maine DEP Bigelow Laboratory University of Maine U.S. Fish and Wildlife Maine Dept. of Marine Res. Casco Bay Estuary Project Bigelow Laboratory Bigelow Laboratory University of New Hampshire Bigelow Laboratory Darling Marine Center - UNH Maine DEP University of New Hampshire Maine DEP University of Maine Kennebec/Androscoggin Rivers Seth Barker* Lee Doggett* Chris Garside* Peter Larsen* Theodore Loder* Lawrence Mayer* Paul Mitnik* Byard Mosher* John Sowles* Casco Bay Arnold Banner* Seth Barker* Lee Doggett* Chris Garside* Chris Heinig Peter Larsen* Lawrence Mayer* Paul Mitnik* Carter Newell Dave Phinney* Frederick Short John Sowles* Maine Dept. of Marine Res. Casco Bay Estuary Project Bigelow Laboratory Bigelow Laboratory University of New Hampshire Darling Marine Center - UNH Maine DEP University of New Hampshire Maine DEP U.S. Fish and Wildlife Maine Dept. of Marine Res. Casco Bay Estuary Project Bigelow Laboratory Intertide Corporation Bigelow Laboratory Darling Marine Center - UNH Maine DEP Great Eastern Mussel Farm Bigelow Laboratory University of New Hampshire Maine DEP Saco Bay Seth Barker* Lee Doggett* Chris Garside* Chris Heinig Peter Larsen* Paul Mitnik* Carter Newell Frederick Short John Sowles* Great Bay Chris Garside* Frederick Short Hampton Harbor David Burdick Richard Langan Arthur Mathieson Stephen Jones Merrimack River n/a Plum Island Sound Charles Hopkinson, Jr. Massachusetts Bay Larry Cahoon Cathy Coniaris* Michael Connor Jack Kelly Theodore Loder* Caroline Martorano* James Maughn Michael Mickelson Candace Oviatt Boston Harbor Michael Connor Kenneth Keay Jack Kelly Cape Cod Bay Cathy Coniaris* Michael Connor Theodore Loder* Caroline Martorano* Maine Dept. of Marine Res. Casco Bay Estuary Project Bigelow Laboratory Intertide Corporation Bigelow Laboratory Maine DEP Great Eastern Mussel Farm University of New Hampshire Maine DEP Bigelow Laboratory University of New Hampshire University of New Hampshire University of New Hampshire University of New Hampshire University of New Hampshire Woods Hole Ocean. Institute University of NC, Wilmington University of New Hampshire MA Water Resources Authority Independent Contractor University of New Hampshire University of New Hampshire CH2M Hill MA Water Resources Authority University of Rhode Island MA Water Resources Authority MA Water Resources Authority Independent Contractor University of New Hampshire MA Water Resources Authority University of New Hampshire University of New Hampshire 40 Appendix 2: Estuary References The following references were recommended by one or more Eutrophication Survey participants as critical background material for understanding the nutrient enrichment characteristics of individual North Atlantic estuaries. In some cases, the survey results are based directly upon these publications. This list is not comprehensive; some estuaries are not included because no suggestions were received. St. Croix River/Cobscook Bay Davidson, V.M. 1934. Fluctuation in the abundance of planktonic diatoms in the Passamaquoddy region, New Brunswick, from 1924-1931. Cont. Can. Biol, New se- ries 8: 359-407. Fefer, S.I. and P.A. Schettig. 1980. An ecological char- acterization of coastal Maine (north and east of Cape Elizabeth) Volume 2. FWS/OBS-80/29. Newton Cor- ner, MA: United States Fish and Wildlife Service. Gran, H.H. and T. Braarud. 1935. A quantitative study of the phytoplankton in the Bay of Fundy and the Gulf of Maine (including observations on hydrography, chemistry and trubidity). Journal of Biological Bd. Can. 1: 279-467. Kelly, J.R. and P.S. Libby. 1996. Final report on dissolved oxygen levels in select Maine estuaries and embayments. Wells Bay National Estuarine Research Reserve and Maine Dept. of Environmental Protection. Shenton, E.H. and D.B. Horton. 1973. Literature review of the marine environmental data for Eastport, Maine. TRIGOM publication, report no. 2A. 130p. + appendi- ces. Shumway, S.E., S. Sherman-Caswell, and J.W. Hurst. 1988. Paralytic shellfish poisoning in Maine: monitor- ing a monster. Journal of Shellfish Research 7(4): 643- 652. Wildish, D.J., J.L. Martin, A.J. Wilson, and M. Ringuette. 1990. Environmental monitoring of the Bay of Fundy salmonid mariculture industry during 1988-89. Can. Tech. Rep. Fish. Aquat. Sci. Rept. No. 1760. 126 p. Wildish, D.J., P.D. Keizer, A.J. Wilson and J.L. Martin. 1993. Seasonal changes of dissolved oxygen and plant nutrients in seawater near salmonid net pens in the macrotidal Bay of Fundy. Can. J. Fish. Aquat. Sci. 50: 303-311. Englishman Bay Fefer, S.I. and P.A. Schettig. 1980. An ecological char- acterization of coastal Maine (north and east of Cape Elizabeth) Volume 2. FWS/OBS-80/29. Newton Cor- ner, MA: USFWS. Shumway, S.E., S. Sherman-Caswell, and J.W. Hurst. 1988. Paralytic shellfish poisoning in Maine: monitor- ing a monster. Journal of Shellfish Research 7(4): 643- 652. Narraguagus Bay Fefer, S.I. and P.A. Schettig. 1980. An ecological charac- terization of coastal Maine (north and east of Cape Elizabeth) Volume 2. FWS/OBS-80/29. Newton Cor- ner, MA: USFWS. Shumway, S.E., S. Sherman-Caswell, and J.W. Hurst. 1988. Paralytic shellfish poisoning in Maine: monitor- ing a monster. Journal of Shellfish Research 7(4): 643- 652. Blue Hill Bay Fefer, S.I. and P.A. Schettig. 1980. An ecological charac- terization of coastal Maine (north and east of Cape Elizabeth) Volume 2. FWS/OBS-80/29. Newton Cor- ner, MA: USFWS. Kelly, J.R. and P.S. Libby. 1996. Final report on dissolved oxygen levels in select Maine estuaries and embayments. Wells Bay NERR and Maine DEP. Shumway, S.E., S. Sherman-Caswell, and J.W. Hurst. 1988. Paralytic shellfish poisoning in Maine: monitor- ing a monster. Journal of Shellfish Research, Vol. 7, No. 4, 643-652. Penboscot Bay Fefer, S.I. and P.A. Schettig. 1980. An ecological charac- terization of coastal Maine (north and east of Cape Elizabeth) Volume 2. FWS/OBS-80/29. Newton Cor- ner, MA: USFWS. Kelly, J.R. and P.S. Libby 1996. Final report on dissolved oxygen levels in select Maine estuaries and embayments. Wells NERR and Maine DEP. 41 ■Villi S Estuarine Eutroplmation Survey Volume 3 - North Atlantic Shumway, S.E., S. Sherman-Caswell, and J.W. Hurst. 1°SS. Paralytic shellfish poisoning in Maine: monitor- ing a monster. Journal of Shellfish Research7(4): 643- 652. Muscongus Bay Fefer, S.I. and PA. Schettig. 1980. An ecological charac- terization of coastal Maine (north and east of Cape Elizabeth) Volume 2. FWS/OBS-80/29. Newton Cor- ner, MA: USFWS. Hurst, J.W. and CM. Yentsch. 1981. Patterns of toxification of shellfish in the Gulf of Maine coastal wa- ters. Can. J. Fish. Aquat. Sci. 38: 152-156. Kelly, J. R. and PS. Libby. 1996. Final report on dissolved oxygen levels in select Maine estuaries and embayments. Wells Bay NERR and Maine DEP. Shumway, S.E., S. Sherman-Caswell, and J.W. Hurst. 1988. Paralytic shellfish poisoning in Maine: monitor- ing a monster. Journal of Shellfish Research 7(4): 643- 652. Damariscotta River Fefer, S.I. and PA. Schettig. 1980. An ecological charac- terization of coastal Maine (north and east of Cape Elizabeth) Volume 2. FWS/OBS-80/29. Newton Cor- ner, MA: USFWS. Hurst, J.W. and CM. Yentsch. 1981. Patterns of toxification of shellfish in the Gulf of Maine coastal wa- ters. Can. J. Fish. Aquat. Sci. 38: 152-156. Incze, L. and C. Yentsh. 1981. Stable density fronts and dinoflagellate patches in a tidal estuary. Estuarine Coastal and Shelf Science 13:547-556. Mayer, L. M. 1982. Retention of riverine iron in estuar- ies. Geochimica et Cosmochimica Acta. 46:1003-1009. Shumway, S.E., S. Sherman-Caswell, and J.W. Hurst. 1988. Paralytic shellfish poisoning in Maine: monitor- ing a monster. Journal of Shellfish Research 7(4): 643- 652. Sheepscot Bay Fefer, S.I. and PA. Schettig. 1980. An ecological charac- terization of coastal Maine (north and east of Cape Elizabeth) Volume 2. FWS/OBS-80/29. Newton Cor- ner, MA: USFWS. Garside, C. G. Hull, and CS. Yentsch. 1978. Coastal source waters and their role as a nitrogen souce for primary production in an estuary in Maine. In: M.L. Wiley (ed), Estuarine Interactions. Academic Press, New York, San Francisco, London, pp. 565-575. Hurst, J.W. and CM. Yentsch. 1981. Patterns of intoxification of shellfish in the Gulf of Maine coastal waters. Can. J. Fish. Aquat. Sci. 38: 152-156. Mayer, L. M. 1982. Retention of riverine iron in estuar- ies. Geochimica et Cosmochimica Acta. 46:1003-1009. Shumway, S.E., S. Sherman-Caswell, and J.W. Hurst. 1988. Paralytic shellfish poisoning in Maine: monitor- ing a monster. Journal of Shellfish Research 7(4): 643- 652. Kennebec/Androscoggin Rivers Fefer, S.I. and PA. Schettig. 1980. An ecological charac- terization of coastal Maine (north and east of Cape Elizabeth) Volume 2. FWS/OBS-80/29. Newton Cor- ner, MA: USFWS. Hurst, J.W. and CM. Yentsch. 1981. Patterns of toxification of shellfish in the Gulf of Maine coastal wa- ters. Can. J. Fish. Aquat. Sci. 38:152-156. Shumway, S.E., S. Sherman-Caswell, and J.W. Hurst. 1988. Paralytic shellfish poisoning in Maine: monitor- ing a monster. Journal of Shellfish Research 7(4): 643- 652. Casco Bay Fefer, S.I. and PA. Schettig. 1980. An ecological charac- terization of coastal Maine (north and east of Cape Elizabeth) Volume 2. FWS/OBS-80/29. Newton Cor- ner, MA: USFWS. Hurst, J.W. and CM. Yentsch. 1981. Patterns of toxification of shellfish in the Gulf of Maine coastal waters. Can. J. Fish. Aquat. Sci. 38:152-156. Kelly, J.R. and PS. Libby. 1996. Final report on dissolved oxygen levels in select Maine estuaries and embayments. Wells NERR and Maine DEP. Saco Bay Mayer. L. M. 1982. Retention of riverine iron in estuar- ies. Geochimica et CosmochimicaActa. 46:1003-1009. Great Bay Daley, M.A., AC. Mathieson, and T. L. Norall. 1979. Temperature, salinity, turbidity and light attenuation in the Great Bay estuary system. 1974-1978. JEL Con- tribution Series no. 85. 42 NOAA's Esiuarine Eutrophication Survey: Volume 3 - North Atlantic Jones, S.H. and R. Langan. 1996. Assessment of nonpoint source pollution in tributaries entering Great Bay. Final Report. Concord, NH: NH Office of State Planning, NH Coastal Program. Jones, S.H. and R. Langan. 1995. Assessment of nonpoint source pollution in tributaries entering Great Bay. Final Report. Concord, NH: NH Office of State Planning, NH Coastal Program. Jones, S.H. and R. Langan. 1995. Assessment of bacte- rial and nutrient contamination from subsurface dis- posal systems in the seacoast area. Final Report. Con- cord, NH: NH Office of State Planning, NH Coastal Program. Jones, S.H. and R. Langan. 1995 Strategies for assess- ing nonpoint source pollution impacts on coastal wa- tersheds. Final Report. Concord, NH: NH Office of State Planning, NH Coastal Program. Jones, S.H. and R Langan. 1994. Assessment of nonpoint source pollution in tributaries entering Great Bay. Fi- nal Report. Concord, NH: NH Office of State Planning, NH Coastal Program. Jones, S.H and R. Langan. 1994. Land use impacts on coastal water quality in NH. Final Report. Concord, NH: NH Office of State Planning, NH Coastal Program. Jones, S.H. and R. Langan. 1993 Nonpoint source pol- lution in the Oyster River watershed, NH. Final Re- port. Concord, NH: NH Office of State Planning, NH Coastal Program. Langan, R. and S.H. Jones. 1996. A monitoring plan for the Great Bay Estuarine Research Reserve. Final report for year 5. NOAA Tech. Memo. NA170RO182-05 Langan, R. and S.H. Jones. 1995. A monitoring plan for the Great Bay Estuarine Research Reserve. Final report for year 3.5. NOAA Tech. Memo. NA170RO182-04. Langan, R. and S.H. Jones. 1995. A monitoring plan for the Great Bay Estuarine Research Reserve. Final report for year 3. NOAA Tech. Memo. NA170RO182-03. Langan, R. and S.H. Jones. 1994. A monitoring plan for the Great Bay Estuarine Research Reserve. Final report for year 2. NOAA Tech. Memo. NA170RO182-02 Langan, R. and S.H. Jones. 1993. A monitoring plan for the Great Bay Estuarine Research Reserve. Final report for year 1. NOAA Tech. Memo. NA170RO182-01. Langan, R. 1994. Characterization of water column con- ditions in the vicinity of the Portsmouth Naval Ship- yard. In: Johnston, R.K. et al. (eds.), An Estuarine Eco- logical Risk Assessment Case Study for Naval Ship- yard Portsmouth, Kittery, Maine. Phase I: Problem For- mation. US EPA, US Navy NCCOSC, NRaD Technical Report 1627. Loder, T.C., J.A. Love, J. P. Kim, and C.G. Wheat. 1983. Nutrient and hydrographic data for the Great Bay es- tuarine system, New Hampshire-Maine, Part II. Janu- ary 1976-June 1978. UNH Marine Program Publication UNH-MP-D/TR-SG-83-4. Mitnik, P. 1994. Salmon Falls River waste load alloca- tion. Maine DEP, Bureau of Land and Water Quality. Mitnik, P. and D. Valleau. 1996. Salmon Falls/ Piscataqua River WAtershed TDML Project Data Re- port. April 1996. Maine DEP and NEIWPCC. Norall, T. L. and A.C. Mathieson. 1976. Nutrient and hydrographic data for the Great Bay estuarine system and the adjacent open coast of New Hampshire-Maine. JEL Contribution Series. Norall, T.L., A.C. Mathieson, and CE. Penniman. 1982. Nutrient and hydrographic data for the Great Bay es- tuarine system, New Hampshire-Maine. Part I. Septem- ber, 1973-December 1975. JEL Contribution Series 150. UNH-D/TR-83-1. Swift, M.R., J. Scott, J. Debois, A. Bilgili, S.H. Jones, R. Langan, and B. Celikkol. 1996. Nonpoint source mod- eling of the Oyster River. Final report submitted to the NH Coastal Program, NHOSP. September 1996. Reid, A., B.S. Meeker, J. Morrill, and D. Burt. 1995. Great Bay Watch annual report. Durham, NH: Great Bay Watch. 53 pp. + apps. Hampton Harbor Jones, S.H., R. Langan, L.K. Branaka, T.P. Ballestero, and D. Marquis. 1996. Assessment of septic system design criteria on coastal habitats and water qualitv. Final Report. Concord, NH: NH Office of State Plan- ning, NH Coastal Program. 143p. Jones, S.H., R. Langan, L.K. Branaka, D. Marquis, and T.P. Ballestero. 1995. Assessment of bacterial and nu- trient contamination from subsurface disposal systems in the Seacoast area. Final Report. Concord, NH:NH Office of State Planning, NH Coastal Program. 50 p. Mathieson, A.C. and R.A. Fralick. 1972. Investigations of New England marine algae. V. The algal vegetation of the Hampton-Seabrook estuary and the open coast near Hampton, New Hampshire. Rhodora 74:799-827. Mathieson, A.C. 1969. A floristic and descriptive eco- logical study of the Hampton-Seabrook Estuary and the adjacent open coast of New Hampshire. UNH/JEL 43 Ni'.ll - I'fluannt Eutmphicatiott Survey: Volume 3 - North Atlantic report. JI£L Contribution Series #85. Normandeau Associates. 1996. Seabrook station 1995 environmental studies in the Hampton-Seabrook Area: a characterization of environmental conditions during the operation of the Seabrook Station. Northeast Utili- ties Company Publication. Plum Island Sound Alderman, D., B. Balsis, I. Buffam, R. Garritt, C. Hopkinson, and J. Vallino. 1995. Pelagic metabolism in the Parker River/ Plum Island Sound Estuarine System. Biological Bulletin 189:250-251. Balsis, B., D. Alderman, I. Buffam, R. Garritt, C. Hopkinson, and J. Vallino. 1995. Total system metabo- lism in the Plum Island Sound estuary. Biological Bul- letin 189:252-254. Hopkinson, C. S. and J. Vallino. 1995. The relationship between man's activities in watersheds and estuaries: a model of runoff effects on estuarine community me- tabolism. Estuaries 18:598-621. Ingram, K., C. S. Hopkinson, K. Bowman, H. Garritt and J. Vallino. 1994. From watershed to estuary: assess- ment of nutrient loading, retention and export from the Ipswich River Basin. Biol. Bull. 187:277-278. Peterson, B. J. , B. Fry, M. Hullar, S. Saupe, and R. Wright. 1994. The distribution and stable isotopic com- position of dissolved organic carbon in estuaries. Estu- aries 17:111-121. Vallino, J. , C. Hopkinson and J. Hobbie. 1996. Model- ing bacterial utilization of dissolved organic matter: optimization replaces Monod growth kinetics. Limnol. Oceanogr. 41(8):1591-1609. Wright, R.T and R.B. Coffin. 1983. Planktonic bacteria in estuaries and coastal waters of northern Massachu- setts: spatial and temporal distribution. Marine Ecol- ogyProgress Series 11:205-216. Townsend, D.D., L.M. Cammen, J. P. Christensen, S.J. Eckleson, M.D. Keller, E.M. Haugen, S. Corwin, W.K. Bellows, and J.F. Brown. 1991. Seasonality of oceano- graphic conditions in Massachusetts Bay. Technical Report No. 83. West Boothbay Harbor, ME: Bigelow Laboratory for Ocean Sciences. 114 pp. Boston Harbor Galya, D.P, J. Bleiler, and K. Hickey. 1996. Outfall moni- toring overview report: 1994. Environmental Quality Department technical report series No. 96-4. Boston, MA: Massachusetts Water Resources Authority. 50 p. Kelly, J.R. and J. Turner. 1995. Water column monitor- ing in Massachusetts and Cape Cod Bays: anuual re- port for 1994. Environmental Quality Department tech- nical report series No. 95-17. Boston, MA: Massachu- setts Water Resources Authority, 163 p. Townsend, D.D., L.M. Cammen, J. P. Christensen, S.J. Eckleson, M.D. Keller, E.M. Haugen, S. Corwin, W.K. Bellows, and J.F. Brown. 1991. Seasonality of oceano- graphic conditions in Massachusetts Bay. Technical Report No. 83. West Boothbay Harbor, ME: Bigelow Laboratory for Ocean Sciences. 114 pp. Cape Cod Bay Gardner, G.B., T.A. Villereal, T.C. Loder, V. Schneider Graham, C. Lefebvre, C. Coniaris. in review. Biological and physical processes controlling nutrient dynamics and primary production in Cape Cod Bay. Boston, MA: Massachusetts Bays Program. Kelly, J.R. and J. Turner. 1995. Water column monitor- ing in Massachusetts and Cape Cod Bays: anuual re- port for 1994. Environmental Quality Department tech- nical report series No. 95-17. Boston, MA: Massachu- setts Water Resources Authority, 163 p. Massachusetts Bay Galya, D.P, J. Bleiler, and K. Hickey. 1996. Outfall moni- toring overview report: 1994. Environmental Quality Department technical report series No. 96-4. Boston, MA: Massachusetts Water Resources Authority. 50 p. Kelly, J.R. and J. Turner. 1995. Water column monitor- ing in Massachusetts and Cape Cod Bays: annual re- port for 1994. MWRA Environmental Quality Depart- ment Technical Report Series No. 95-17. Massachusetts Water Resources Authority, Boston, MA. 163 pp. 44 Appendix 3: NEI Estuaries One hundred twenty-nine estuaries are included in the National Estuarine Inventory (NEI). Some estuaries are actually subsystems of larger estuaries, although each is being evaluated indepedently for the Eutrophication Survey project (e.g., Potomac River is a sub-system of Chesapeake Bay). There are additional estuaries characterized for the Eutrophi- cation Survey project that are not NEI estuaries. However, those estuaries may be added to the NEI in the future. For more information on the National Estuarine Inventory, see the inside front cover of this report. North Atlantic (16) Passamaquoddy Bay Englishman Bay Narraguagus Bay Blue Hill Bay Penobscot Bay Muscongus Bay Damariscotta River Sheepscot Bay Kennebec/Androscoggin Rivers Casco Bay Saco Bay Great Bay Merrimack River Massachusetts Bay Boston Bay Cape Cod Bay Mid Atlantic (22) Buzzards Bay Narragansett Bay Gardiners Bay Long Island Sound Connecticut River Great South Bay Hudson River/Raritan Bay Barnegat Bay New Jersey Inland Bays Delaware Bay Delaware Inland Bays Maryland Inland Bays Chincoteague Bay Chesapeake Bay Patuxent River Potomac River Rappahannock River York River James River Chester River Choptank River Tangier/Pocomoke Sounds South Atlantic (21) Albemarle/Pamlico Sounds Pamlico/Pungo Rivers Neuse River Bogue Sound New River Cape Fear River Winyah Bay North /South Santee Rivers Charleston Harbor Stono/ North Edisto Rivers St. Helena Sounds Broad River Savannah River Ossabaw Sound St. Catherines/Sapelo Sounds Altamaha River St. Andrew /St. Simons Sounds St. Marys R. /Cumberland Snd St. Johns River Indian River Biscayne Bay Gulf of Mexico (36) Florida Bay South Ten Thousand Islands North Ten Thousand Islands Rookery Bay Charlotte Harbor Caloosahatchee River Sarasota Bay Tampa Bay Suwannee River Apalachee Bay Apalachicola Bay St. Andrew Bay Choctawhatchee Bay Pensacola Bay Perdido Bay Mobile Bay Mississippi Sound Lake Borgne Lake Pontchartrain Breton/Chandeleur Snds Mississippi River Barataria Bay Terrebonne /Timba Her Bays Atchafalaya/Vermilion Bays Mermentau Estuary Calcasieu Lake Sabine Lake West Galveston Bay Coast Brazos River Matagorda Bay San Antonio Bay Aransas Bay Corpus Christi Bay Upper Laguna Madre Baffin Bay Lower Laguna Madre West Coast (34) Tijuana Estuary San Diego Bay Mission Bay Newport Bay San Pedro Bay Alamitos Bay Anaheim Bay Santa Monica Bay Morro Bay Monterey Bay Elkhorn Slough San Francisco Bay Cent. San Francisco Bay/ San Pablo/Suisun Bays Drakes Estero Tomales Bay Eel River Humboldt Bay Klamath River Rogue River Coos Bay Umpqua River Siuslaw River Alsea River Yaquina Bay Siletz Bay Netarts Bay Tillamook Bay Nehalem River Columbia River Willapa Bay Grays Harbor Puget Sound Hood Canal Skagit Bay North Atlantic Mid Atlantic South Gulf of V Atlantic Mexico A U.S. GOVERNMENT PRINTING OFFICE: 1997 41S-5Q2 40042 45 V? °' c<\ £flj^v *'*rf , C ' ^BP PF.NN STATE UNIVERSITY LIBRARIES ADDDD31b?27S7