DEPARTMENT OF THE ARMY CORPS OF ENGINEERS THE BULLETIN OF THE BEACH EROSION BOARD OFFICE, CHIEF OF ENGINEERS WASHINGTON, D.C. el Woods Hole ie Oe hi Institution JULY 1957 Vol, “ No. [ TGS MBL/WHOI OA 0 0301 0044935 1 TABLE OF CONTENTS Model Tests of Wave Run-up for Hurricane Protection Project @eeseeeoeeeceoeneee ees eevee eec en @ Wave Refraction Plotter @ecesveveereee2eseeee2e000e2% Status of Research in Shore Line Protection ., Tests of River Crest Stage Gage Under Wave Action eeoeeeeeeveeeeeeeeeeneeeeeeee2ee0e0200 Progress Reports on Research Sponsored by the Beach Erosion Board e@eeeeeeveeveeveeeeeoeeeveee e080 List of Beach Erosion Board Technical Memo= randa @eeeevoseeeeceeveaeeeee2eeoeeeeeseeeeex2eee2e00 Beach Erosion Studies e@eeveeceeveteooeeeeoeeeveeeee Page No, 13 17 28 34 40 44, MODEL TESTS OF WAVE RUN=UP FOR HURRICANE PROTECTION PROJECT by Rudolph P. Savage Research Division, Beach Erosion Board Studies of protection for coastal areas against erosion damages and lowland flooding associated with the extreme high tide levels and wave action accompanying hurricanes are currently being made in several of the coastal divisions of the Corps of Engineers, A feasible method for providing this type of protection is the restoration or creation of an adequate dune barrier and protective beach by placement of suitable sand fill, In connection with a current investigation of this problem for an area which is exposed to the Atlantic Ocean it was necessary to evaluate the wave run-up to be expected for certain beach and dune conditions, In order to evaluate the wave run-up, an un- distorted 1:20 scale fixed-bed model of a representative section of the proposed fill and nearshore topography of the area was built in a wave tank at the Beach Erosion Board and the wave run-up was measured with tide and wave conditions believed to be representative of storm and/or hurricane design conditions for the area. Since these tests give information on one of the problems associ- ated with hydraulic fill design, the data from the tests are being presented for possible use in other problems of this type. It is realized that the conditions encountered in other problems may differ from those given here, but it is believed that the data may have ap- plication in some cases. The set-up for the model tests, shown in Figure 1, was installed in a wave tank 96 feet long, 2 feet deep, and 14 feet wide, The average profile for the offshore section. (see Figure 1) was obtained from a hydrographic survey made in the study area in 1955 and 1956, and was derived by using the intersection of mean sea level with the beach profile as a reference point in both the horizontal and vertical directions and then averaging selected measurements for all profiles except those in the immediate vicinity of an inlet, Assuming that within a short time after completion of the fill a similar profile would be formed (although located some distance seaward of the original profile), the beach and nearshore topography was constructed in the wave tank to a configuration as near that of the average profile as practicable using straight-line shapes, A dune slope of 1:10 approx- imates the present average value for existing dunes. The offshore bar in the tank model was composed of fine sand covered with a 43-inch layer of smooth concrete. The 1:20 beach foreshore slope, 1:10 and 1lom5dune slopes, and the berm of the beach were constructed of 3/4- inch plywood, Preliminary to the actual testing, wave generator settings were determined which would give the desired wave heightsseaward of the dN-NNY 3AVM JO SLS3L YOS dN-L3S TAGOW | SyYNdIS Japow-4e04 Sb Ov GE o£ rd oz sl (0) S (0) S- Ol- GI- Oz- Gz- 006 008 j o0¢ 002 001 002 - o0¢- adhjojoug—jae4 26] YoIDW pibog uolso1g yodeg (YySiuly ajau9U09 YyIM puUDS ) yudDL JO yODg 4Dq as0ys) Wwo}jOoq yud) (o) fo) wo + wo x (o) + aii TSW tbl+puo ‘Ol poe aes pos aa ee . Sl Ot sadojs aunp G:| pud Ol|——~ i NY 00" 1+ yuoy jo doy ——7 auab aADM adAjojo1g—1904 te} = os ‘Ot ¢ abn ayijoad japow (9G, -SS61) ajlyoud adAyoyoud abosaAy———— (yuawaonid }I! 42130) aj1youd adAyojoud abouaAD pasoipaid |apoW-4924 bar for all water depths and wave periods. Wave heights were measured during the tests at the positions indicated in Figure 1, Prototype water elevations of +9 feet and +6 feet MSL were tested with prototype wave periods of 8 and 12 seconds and wave heights ranging from 6 to 12 feet, prototype. Alli of these conditions were tested with berm crest elevations of +6, +8 and +10 feet MSL, berm widths of 50 feet and 150 feet, and dune slopes of 1:10 and 1:5, These test conditions and results are given in Tables 1 through 6. Later computations indicated that it was possible to have a surge peak of +14 feet MSL in the area, and so further tests were made using this water level with berm elevations of +10.0 and +14.0 feet MSL, a dune slope of 1:5, and slightly different wave heights, The latter test conditions and results are shown in Tables 7 and 8, The average wave run-up (determined by averaging the run-up for 9 to 15 waves disregarding the first 2 or 3 waves) is given in Tables 1 to 7, These values were obtained by comparing the run-up for two runs and; if agreement was good, no further runs were made, If agreement was not good, further runs were made to give a more re~ presentative average value. 8 In most of the tests the average run-up for the two runs agreed very well, differences being on the order of 0,0 to 0.2 foot (prototype), For these runs, the highest average run-up observed is given in Tables 1 to 7 if the difference was 0.1 foot, and the average value of the two runs is given if the difference was 0.2 foot. If the difference between the average run-up for the first two runs differed by more than 0.2 foot, the most consistent value of run-up is given, (Only 2 runs differed by 0.4 foot and 4 runs by 0.3 foot.) Wave heights were the same for all sets of runs, For the data shown in Table 8, the run-up values measured were erratic. Simce the reason for this erratic variation was unknown, it was believed that the average of the highest 1/3 of the run-up values would be more representative than the average run-up value. Consequently both the average run-up and the average of the highest 1/3 of the run-up values are given in Table 8. Waves breaking on the 1:20 beach slope and moving across the beach berm caused a layer of water to stand on the berm. This stand or set-up is given as "water set-up at toe of dunes" (Tables 1 through 8). When this set-up is added-to the "still water depth over the berm" (Tables 1 through 8), the “active water depth over the berm at toe of dunes" is obtained. The footnote "Breaks over bar" in Tables 1 to 7 designates any energy dissipation by turbulence as the wave passed over the bar and does not necesSarily indicate a plunging breaker. It may refer to a momentary "whitecap" or a "spilling" of the wave over a longer period of time, Calculations based on the solitary wave theory and empirical curves for breaker depth versus deep water wave steepness! indicate that none of the waves used in the tests with a 14-foot berm elevation should have broken in the 21,5 feet of water over the bar. For example, the calculations give a breaking depth of approximately 16 feet for the wave of 12-foot height and 8-second period and a breaking depth of approximately 20 feet for the 12-foot high, 12-second wave, These test waves did break however, and the most probable explanation is that the theoretical and empirical curves apply to the breaker depth for waves travelling up a continuous slope and may fail when the slope abruptly levels, This explanation is supported by the observa- tion that the test waves did not necessarily break on the seaward slope of the bar, but frequently spilled briefly over the level top of the bar, or in some cases, after passing the bar. 1, Beach Erosion Board, "Shore Protection Planning and Design", Beach Erosion Board Technical Report No. 4, June 1954, pp. 48=50. 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(4d) zeq B-V.Xs) yydep J3azeM 12 WAVE REFRACTION PLOTTER by R. Q. Palmer, Chief, Civil Works Branch Honolulu Area, San Francisco District U. S. Army Corps of Engineers The Honolulu Area of the San Francisco District, Corps of Engineers, recently prepared design analyses for several projects, each requiring a series of refraction diagrams. These diagrams were con- structed in accordance with instructions contained in Technical Report No. 4 of the Beach Erosion Board entitied "Shore Protection Planning and Design. The first series of refraction diagrams was constructed using a template, 1] iilustrated on figure 17 of Technical Report No. 4. The template is a great improvement over previous devices used and it can be used with charts of any scale. Nevertheless, the work was time consuning -nd occasional errors were made due to slippage of the template or triangles used to orient the template. To overcome these problems. the template was adapted to a wave refraction plotter which could be attached to an ordinary drafting machine2! (see Figure 1). Time trials by technicians trained on an equal period of time with both the template and the plotter showed that the production rate when using the plotter was more than twice that when using the template and fewer errors were made, Plotters can be fabricated for about $15 each in quantities of 2 or 3, but could be produced for about $10 each in amounts of 50 to 100, Hydrographic work charts are prepared in the same manner as when using the template. The plotter is oriented for the selected deep water wave direction and the azimuth on the drafting machine is set at zero. The lower motion is then locked, The upper motion of the drafting machine is freed and deflections are turned with the plotter. At all other times both motions are locked to fix the orientation of the plotter, The built-in pivot point is de= presSed with the palm of the hand when turning the deflection angles. A spring raises the pivot point when released, After each deflection angle is turned, the plotter is shifted slightly to bring the right angle- straightedge into position for extending the orthogonal, In the event that the orthogonal intersects the contours at angles less than 10 de- grees, this fact is shown by angle markings on the plotter. Thus, guesswork or continual checking to determine when it is necessary to change either to or from the R/J method is eliminated, When a change to the R/J method is required, it is only necessary to read the azimuth on the drafting machine and by ready reference to the chart attached 1| After Arthur, Munk & Issacs, 1952 2) When a drafting machine is used which has "stops" at 15-degree incre- ments, the trigger on the "stop"’ should be depressed by placing a number of rubber bands around the control knob, 13 SNIHOVW ONILAVYG OL GSHOVLLV Y311071d =< NOILOVYS3SY SAVM ‘| SYNdSI4 4 (dN-3SO19) YALLONd NOILOWYSSY 3AVM “2 3SYNdIS ———— ae tence Ment tte pete yeas es ro c Cg a ms e 15 to the plotter, the new azimuth is computed and set on the drafting machine to orient the plotter, Then the orthogonal is extended using the right angle-straightedge. Thus there is no loss of time in chang- ing from one method to the other, In beginning the trace cf each new orthogonal from deep water, the azimuth on the drafting machine is again set at zero degree; thus the plotter is properly oriented with- out other reference, For convenience the proper table of values of C,/c may be attached to the plotter as shown on the photograph in Figure 2, STATUS OF RESEARCH IN SHORE LINE PROTECTION by Joseph M, Caldwell Chief, Research Division, Beach Erosion Board Corps of Engineers, Department of the Army This paper was prepared for and delivered at the August 1955 meeting of the American Society of Civil Engineers at Berkeley, California. Since this paper was not printed in the Proceeding of the American Society of Civil Engineers nor included as one of their separates, but does rather completely sum up the overall picture regarding the status of investigation and knowledge in the field of coastal engineering, it is reproduced here as infor- mation of probable interest to readers of the Bulletin, Increasing use of the shores of the United States for recreation and seasonal housing developments has created greater public interest in the development of shore protection measures, Eroding shores have historically presented very interesting geological studies, but when the erosion exposes homes, roads, piers, parking lots, restaurants, hotels, railroads, canneries, beach clubs, and other miscellaneous con= structions to undermining and wave damage, the study of shore line protection becomes of more practical and immediate concern, The difficulty and expense of isolating and measuring the wave forces and shore characteristics which produce erosion militated against controlled research in this field until the economic pressure became great enough to clearly justify such action, Programmed research in this field began some fifteen years or so ago and has been accelerated since 1945 when Congress authorized the Beach Erosion Board of the Corps of Engineers to undertake research in this field, Prior to 1945, shore protection work in this country was done more or less on an empirical basis with relatively little funding to improve the status of knowledge. The empirical approach by itself was not adequate due to the variations in the problem from place to place; it led not only to remarkable successes but also to disappointing failures. Present re- search is generally pointed toward establishing the fundamental concepts of shore processes on a quantitative basis and melding these findings with empirical knowledge in order to make shore protection a practical engineering science, To describe the present status of research in shore line protection, the subject is broken down into three categories: 1, Wave action, i.e., the erosive force. 2. The reaction of the shore to the wave, 3. Improvement works to modify the reaction of the shore to the wave. WAVE ACTION Wave Generation. The generation, transmission, and decay of waves is a rather complex phenomenon, Classical-wave theory (Airy, Gerstner) by itself does little to help the practicing engineer understand the wave action he encounters around the seacoast. Empirical formulae available before 1940 left much to be desired. Present practice finds two basic methods developed in this country for forecasting the genera- tion and decay of waves. The first was developed during World War II to meet the need for accurate wave prediction in connection with amphibious landings; the method uses the concept of "significant waves" and is known as the Sverdrup-Munk method‘! after its developers. The method was subsequently modified by Bret schneider (2), More recently, a newer method of forecasting the generation and decay of wave trains has been developed which considers the entire component spectrum of the wave train in contrast to the Sverdrup=Munk definition of a single wave height and wave period as the significant wave, The more recent method was developed by Dr. Pierson and Dr. Neumann of the College of Engineering of New York University (3,3a), Dr. Darbyshire of England has developed a method(3>) which also results in the prediction of a wave spectrum, The Sverdrup-Munk method has scen widespread use over the past 10 years. The Pierson-Neumann method, being fairly recent and more complex in application, has not yet seen as extensive use, The Beach Erosion Board has had made a 3-year "“hindcast" from Synoptic weather charts using both methods 4,4a), A comparison of the results of these two hindcast studies shows a greater frequency of higher waves by the Sverdrup-Munk method; this difference may be attributed not only to differences in method and theory but also to the actual application of the methods (such as weather map analysis). Unfortunately there are not sufficient wave observations to check the relative accuracy of the two methods. Actually, both methods are completely dependent on accurate meteorological estimates of the velocity, extent, and duration of the winds which develop a given wave train, Further improvement in wave forecasting may accordingly have to await further developments in meteorology. Certainly, further improvements will have to await the accumulation of sufficient wave measurements to establish the accuracy of the prediction methods developed, *Numbers in parentheses refer to list of references on pages 23 to 27. 18 Wave Refraction and Diffraction. Considerable work has been done on the theory of wave refraction and diffraction as a dominant factor “in wave action in shoal waters(5,6,7), The basic concepts are simple; however, the application becomes very complex in an area of even moderately complex hydrography. Work is now under way at the University of California (Berkeley) under contract to the Beach Erosion Board to establish the degree of accuracy of present concepts for predicting wave refraction and diffraction over both simple and moderately complex hydrography. An estimation of the accuracy of existing methods and possibly simpler forms of their application may result from this study. It is to be recognized that the above discussion on refraction applies to simple wave trains only; actually the complex wave trains of the ocean further complicate the application of refraction methods to actual problems. It is felt, however, that a quantitative under standing of ‘the simpler ‘aspects must precede the under standing of the more com- plex aspects. Wave Dissipation, Waves may loose a considerable portion of their energy due to bottom friction and percolation as they move into the shallow water of the Continental Shelf, Theoretical studies of this have been made by Putnam and Johnson(8,9), laboratory studies have been made at the Beach Erosion Board‘10), and field studies in the Gulf of Mexico by Texas A&M Research Foundation 11 - Further progress on this phase of wave action will probably have to await a more comprehensive set of reliable field data showing the energy loss of wave trains travelling over the Continental Shelf, Littoral Currents, Any obliquity of wave attack on the shore re- sults in the generation of a littoral current along the shore face. For the most part these currents are more or less parallel to the shore but occasionally flow away from the shore as rip currents. Whatever their form, they have a considerable influence on shore processes, Due to the combination of complexities of wave actionand irregularities of hydrography that are found in most areas, the attempts to correlate littoral currents with the concurrent wave action have been somewhat disappointing, However, simultaneous observations of waves and littoral currents are being accumulated in increasing numbers, and some satisfactory correlation of the two should be expected within the next 3 or 4 years. Theoretical formulae are available (Putnam, Munk and Traylor (12) which develop the alongshore littoral current velocities to be expected from a simple, uniform wave train; however, the complexities of the natural ocean wave trains complicate the application of the method to natural conditions, Some work has been done on the gaining of a quantitative understanding of rip currents (Shepherd) (13) | but much remains to be done. SHORE PROCESSES Sand Movement, The movement of beach sands by wave action is poorly understood at the present time, However a number of studies have recently been commana 22 eo MTC or are now under way which should serve in the development of a quantitative understanding of this phenomenon, A laboratory study at Massachusetts Institute of Technology(19) ddals with the sorting action of waves on beach sands which results in the pulling of the fines into deep water; a laboratory study at the University of California(20) deals with the problem of fundamental mechanics of movement of sand particles by wave action, A field study at Scripps Institution of Oceanography deals with the seasonal changes in bottom depths from the shore line out to atout the 100-foot depth contour, These studies are sponsored by the Beach Erosion Board of the Corps of Engineers and should lay the foundation of a quantitative understanding of sand movement by wave action, Littoral Drift. The mass alongshore movement of sand by wave action is generally the key to shore erosion problems as well as many inlet navigation problems. The actual design of a shore protection plan frequently hinges on a proper estimate of the net rate and direction of littoral drift. At present this rate can usually be estimated accurately only where some structure, such as a breakwater or jetty, has created an impoundment area which enables a volumetric computation to be made. Some method of accurately estimating the rate of drift where no impoundments have taken place is needed. Attempts have been made along this line both in the laboratory(17,21) and in the fie1a(21a)(21b) by working out a correlation of net wave energy upcoast or downcoast with the resulting rate of littoral drift; the results are promising but as yet too fragmentary to justify adoption as a basis of engineering design. Effect of Natural Features. The effects of promontories and of inlets and submarine canyons in modifying the littoral drift and thereby the shore processes have only recently been subjected to intensive study. Studies at Scripps Institution of Oceanography (22) have led to a definition of the effect of submarine canyons on shore processes, Studies at the University of California (Berkeley )(23) have shown that rocky promontories extending out into as much as 30 feet of water are not barriers to the alongshore drift of beach sand, Small-scale studies at the Waterways Experiment Station are demonstrating the inf luence of littoral drift on tidal inlets and of tidal inlets on shore processes, Analytical studies of actual inlets and estuaries are also being made to develop a quantitative understanding of the part that inlets play in shore processes, These particular studies are sponsored by the. Beach Erosion Board and other agencies of the Corps of Engineers, Geologists are devoting an increasing amount of attention to the inshore area and their contributions are helping to clarify many aspects of shore behavior, 62425 From the broad viewpoint, however, the activity in the shore zone at a tidal inlet or the mouth of a large river presents a very complex- 20 problem, Much work remains to te done toward gaining a better under- standing of this feature of the shore. IMPROVEMENT WORKS Shore Structures, Shore structures are generally designed for one of two purposes: to protect the shore against erosion or to improve or shelter a navigation channel or harbor, Each design properly requires an answer to three basic questions: a. What must be the dimensions of the structure to cause it to function as required? b. What will be the forces imposed on the structure? c. What materials can most reasonably meet the required strength and endurance characteristics? The status of research for various types of shore structures relating to shore protection are given briefly in the following paragraphs. Beach Groins. Research is actively under way at the Beach Erosion Board on the proper height, length, spacing and profile of groins. Little work is being done to measure the forces exerted on groins, required strength being estimated largely on the basis of experience, A report on the use of steel in shore structures including groins(26) was issued in 1952 and one dealing with the use of timber 26a) was issued in 1955, The Portland Cement Association has a booklet on concrete(27) and the Asphalt Institute may possibly issue one in the near future. Recent studies at the Waterways Experiment Station for the Bureau of Yards and Docks on the stability of rock mounds have added greatly to our knowledge of the stability of rock structures in wave action(28), Seawalls. The influence of the shape of seawalls on wave run-up and quantity of overtopping water has been the subject of extensive tests for the Beach Erosion Board at the Waterways Experiment Station over the past three years, Vertical-face, stepped-face, curved-face, and sloping-face breakwaters have been tested over a wide range of wave conditions. Some of the results have been published(29 and a compre- hensive report is expected to be published in a year or so by the Beach Erosion Board. Work still needs to be done on erosion at the toe of seawalls, At least two exploratory studies 30,31) have been made recently of the wave forces developed against seawalls; however much additional work is needed before a quantitative understanding is gained. Studies of the suitability of materials for use in seawalls are essentially the same as those mentioned for "beach groins" in the pre- ceding paragraph, 2| Artificial Beaches, The establishment of beaches for rer.eational and protective purposes has come into widespread use in the last fifteen years. The protective effectiveness and stability of these beaches depends on the beach width, berm height, and grain size oi the beach material, The degree to which a hurricane can cut back a beach and the effect of placing sand on the beach of a different size from that normally found thereon ar 35 aay of the questions that still need to be answered. Numerous studies‘3 bearing on this problem of artificial beach design and construction have been made, but additional work must be done before the complete picture can be put together. Breakwaters and Jetties, Though properly considered as navigation improvement structures, breakwaters and jetties sometimes have a significant effect on the adjacent shores. A better understanding of the short term as well as long term effects of these structures on the adjacent shore lines is needed as many of the most severe and costly erosion problems around out coasts have resulted from breakwater and jetty installations which interrupt the littoral drift of sand along the shore, A hydraulic model test of the broad aspects of this problem is planned as a continuation of generalized tests of tidal inlets now under way at the Waterways Experiment Station. The severe downdrift erosion sometimes resulting from the installation of these structures has led to the consideration of means of bypassing the impounded sand past the breakwaters or jetties in order to maintain the downdrift beaches; this is discussed in the next paragraph. Sand Bypassing Methods, The obvious need at some jettied inlets and breakwaters to restore the normal littoral drift by bypassing the impounded sand has led recently to the consideration of methods of pumping the sand past the littoral obstruction, At least three bypassing projects are now in operation in the United States, one at Santa Barbara, California(34,35 » one at South Lake Worth Inlet, Florida(2la), and one at Virginia Beach, Virginia, Three others are in a trial status or under design for Port Hueneme, California, Lake Wor th Inlet, Florida, and Fire Island Inlet, New York. The design of these installations is somewhat problematical at present, the main question centering on what percentage of the net littoral drift can be reached by a fixed pumping plant, a trestle-mounted plant, or a conventional pipe-line dredge, It will probably be another four or five years before a definitive understanding of the best design to fit a given situation will be developed, Key Problems, Two problems which, if solved, would make the design of shore protection works more reliable are: 1, Given the total net littoral drift, determine the quantity of sand being moved alongshore in various depth zones under selected wave conditions, 22 2. Determine how this distribution of alongshore drift with depth is modified by the installation of groins, jetties, breakwaters, and seawalls, These two questions are inherent in all shore protection design pro- blems and are particularly so in the design of fixed sand bypassing plants, An adequate quantitative method of solution to these two problems has yet to be devised, although the preceding portions of this paper show that individual facets of these two problems are being worked on and solved. Recent Publications. In addition to the bibliographical references throughout this paper, there are six additional references of a rather comprehensive nature which, collectively, give a record of the present state of knowledge of shore processes ami the design of shore protection works, together with a picture of the present research effort in this field, Five of those documents(36,37, 8,39,40) are the published proceedings of the five coastal engineering conferences held under the auspices of the Council on Wave Research of the Engineering Founda- tion, Four of these conferences were held in the United States, one each on the shore of the Pacific (1950), the Gulf of Mexico (1951) , the Atlantic (1952), and the Great Lakes (1953). The fifth conference was held in Grenoble, France in 1954, Collectively these five volumes contain 160 papers of interest to engineers and others interested in coastal engineering, The sixth document (41) is Technical Report No, 4 of the Beach Erosion Board, entitled "Shore Protection Planning and Design"', published in 1954 and containing 242 pages plus six appendices, It is felt that the present paper would be incomplete if it failed to mention these six documents. Summary. A review of the statements made in this paper and a study of the references will show that considerable progress has been made over the past 15 years in gaining a quantitative understanding of the fundamentals of shore protection processes, This has resulted from the combined efforts of the meteorologist, the oceanographer, the geologist, the applied mathematician, the research engineer, and the field engineer, Much work remains to be done; however, it is believed that another ten years will probably witness a firming up of our understanding and the placing of most shore protection design on a rational, quantitative basis. REFERENCES ne "Wind, Sea and Swell: Theory of Relations for Forecasting," by H, U, Sverdrup and W. H, Munk, Navy Hydrographic Office, Publication No, 601, 1947, op "Revised Wave Forecasting Relationships," by C, L. Bretschneider, Proceedings of 2nd Conference on Coastal Engineering, Univ. of California, 1952, 23 3a. 4a. 10. ll, "A Unified Mathematical Theory for the Analysis, Propagation and Refraction of Storm Generated Ocean Surface Waves," by W. J. Pierson, Jr., Prepared for Beach Erosion Board and Office of Naval Research, Parts I and II, Research Div., College of Engineering, New York University, 1952, "On Ocean Wave Spectra and a New Method of Forecasting Wind- Generated Sea," by G. Neumann, Beach Erosion Board Tech. Memo, 43, 1953, "The Generation of Waves by Wind", by J. Darbyshire, Proc, Roy. Acad. A., Vol. 215, No. 1122, 1952, "North Atlantic Coast Wave Statistics Hindcast by Bretschneider-= Revised Sverdrup-Munk Method,'' by T. Saville, Jr., Beach Erosion Board Tech, Memo, 55, 1954, "North Atlantic Coast Wave Statistics Hindcast by the Wave Spectrum Method," by G. Neumann and R, W. James, Beach Erosion Board Tech, Memo. 57, 1955. "Graphical Construction of Wave Refraction Diagrams," by J. W. Johnson, M, P. O*Brien and J. D. Isaacs, Navy Hydrographic Office, Publication No. 605, 1948, "A Method for the Graphical Construction of Wave Refraction Diagrams," by T. Saville, Jr., and K, Kaplan, The Bulletin of the Beach Erosion Board, Vol. 6, No. 3, 1952. "The Accuracy of Present Wave Forecasting Methods with Reference to Problems in Beach Erosion on the New Jersey and Long Island Coasts, '' by W. J. Pierson, Jr., Beach Erosion Board Tech. Memo, 24, 1951. "The Dissipation of Wave Energy by Bottom Friction," by J. A. Putnam and J. W. Johnson, Trans. Am. Geoph, Union, Vol. 30, No, 1, 1949. "The Dissipation of Wave Energy by Flow in a Permeable Sea Botton," by J. A. Putnam, Trans. Am, Geoph. Union, Vol, 30, No. 3, 1949, "Laboratory Study of Wave Energy Losses by Bottom Friction and Percolation," by R. P. Savage, Beach Erosion Board Tech. Memo 31, 1953. "Modification of Wave Height Due to Bottom Friction, Percolation and Refraction," by C. L. Bretschneider and R. O. Reid, Beach Erosion Board Tech, Memo, 45, 1954, 24 12. 113} 14, W5' 16, We 18, 19, 20. 2g 21a. 21b. PLeby PIE 24. 256 "The Prediction of Longshore Currents," by J. A. Putnam, W. H. Munk and M. A. Traylor, Trans. Am. Geoph. Union., Vol. 30, 1949, "Longshore Current Observations in Southern California," by Dr. F.P,. Shepard, Beach Erosion Board.Tech. Memo 13, 1950, "Development and Field Tests of a Sampler for Suspended Sediment in Wave Action," by G. M. Watts, Beach Erosion Board Tech. Memo 34, 1953, "Laboratory Study of Equilibrium Profiles of Beaches," by R. L. Rector, Beach Erosion Board Tech. Memo 41, 1954, "Sand Movement by Waves,'’ by T. Scott, Beach Erosion Board Tech, Memo, 48, 1954, "Model Study of Sand Transport Along an Infinitely Long, Straight Beach,"' by T. Saville, Jr., Trans. Am. Geoph. Union, Vol, 31, No. 4, 1950, "Coast Erosion and the Development of Beach Profiles," by P. Bruun, Beach Erosion Board Tech, Memo, 44, 1954, "A Study of Sediment Sorting by Waves Shoaling ona Plane Beach," by A. T. Ippen and P.S. Eagleson, Beach Erosion Board Tech, Memo, 63, 1955. "Mechanics of Bot tom Sediment Movement Due to Wave Action," by M. Manohar, Beach Erosion Board Tech, Memo, 75, 1955. "Sand Transport by Littoral Currents,"' by J. W. Johnson, Proceedings of the 5th Hydraulics Conference, 1952, (Bulletin 34, Studies in Engineering, State Univ. of Iowa) "A Study of Sand Movement at South Lake Worth Inlet, Florida," by G. M. Watts, Beach Erosion Board Tech, Memo, 42, 1953, "Wave Action and Sand Movement Near Anaheim Bay, California", by Joseph M, Caldwell, Beach Erosion Board Tech. Memo. 68, 1956, "Submarine Topography and Sedimentation in the Vicinity of Mugu Submarine Canyon, California," by F.P. Shepard, Beach Erosion Board Tech, Memo, 19, 1950, "Movement of Sand Around Southern California Promontories," by P.D, Trask, Beach Erosion Board Tech, Memo, 76, 1955. "Rational Theory of Delta Formation,” by C. C. Bates, Bulletin Amer, Assoc, of Petroleum Geologist, Vol, 27, No. 9, 1953, "The Source, Transportation and Deposition of Beach Sediment in Southern California," by John W, Handin, Beach Erosion Board Tech, Memo, 22, 1951, 25 26. 26a. 27. 28. 29. 30. 31, 32. O36 34, S5le 36. 37. 38, 39, (NOTE : "Durability of Steel Sheet Piling in Shore Structures," by A. C. Rayner and C. W. Ross, Beach Erosion Board Tech. Memo, 12, 1952. "Ractors Affecting the Economic Life of Timber in Coastal Structures", by Robert A. Jachowski, Beach Erosion Board Tech, Memo, 66, 1955, "Concrete Shore Protection," by Portland Cement Association, Chicago, Illinois, 1940. "Stability of Rubble-mound Breakwaters; Hydraulic Model Investiga-= tion,'' Waterways Experiment Station Tech. Memo. 2-365, 1953. "Experimental Study of Wave Overtopping on Shore Structures," by T. Saville, Jr. and J. M. Caldwell, Proceedings of the International Association for Hydraulic Research, Minneapolis, 1953, "Wave Forces on Breakwaters,” by R. Y. Hudson, Proceedings Am, Society of Civil Engineers, Separate No. 113, 1952. "Laboratory Study of Shock Pressures of Breaking Waves," by - C. W. Ross, Beach Erosion Board Tech, Memo, 59, 1955, "Restudy of Test - Shore Nourishment by Offshore Deposition of Sand, Long Branch, New Jersey,"’ by R. L. Harris, Beach Erosion Board, Tech, Memo 62, 1954, "Beach Rehabilitation by Fill and Nourishment," by J. V. Hall, Jr. and G. M, Watts, Proceedings Am, Society of Civil Engineers, Separate No. 616, March 1955, "Beach Erosion at Santa Barbara, California," U. S. House of Represent atives, 75th Congress, 3rd Session, Document 552, (1938). "Santa Barbara, California, Beach Erosion Control Study," U. S. House of Representatives, 80th Congress, 2nd Session, Document 761, (1949), "Coastal Engineering," by Council on Wave Research, The Engineering Foundation, 1st Conference, Long Beach, California, 1950. (Same as above), 2nd Conference, Houston, Texas, 1951, (Same as above) ,3rd Conference, Boston, Massachusetts, 1952. (Same as above), 4th Conference, Chicago, Illinois, 1953, References 36-40 are published by the Council on Wave Research, The Engineering Foundation, and may be obtained from Council on Wave Research, 244 Hesse Hall, University of California, Berkeley 4, California. ) 26 40. "(Same as.above), 5th Conference, Grenoble, France, 1954, 41. "Shore Protection Planning and Design,'' Tech. Report No. 4, Beach Erosion Board, 1954. (For sale by the Superintendent of Documents, U. S. Government Printing Office, Washington 25, D. C, == Price $2.25.) PATE TESTS OF RIVER CREST STAGE GAGE UNDER WAVE ACTION by Thorndike Saville, Jr. Assistant Chief Research Division Beach Erosion Board ABSTRACT Tests were made of a river crest stage gage to determine the effect of superficial wave action on the maximum stage recorded, with the idea that gages of this type might be adopted for measurements of maximum water elevations in estuaries and adjacent low-lying areas resulting from hurricane surges. Even slight wave action introduced considerable error in the maximum level recorded with the gage as originally planned, but it was found that the gage could be modi- fied in such a way as to result in a maximum error of only a few tenths of a foot even with relatively high wave action. The Beach Erosion Board was requested by the U. S. Weather Bureau to make some observations of the effect of wave action on the maximum water level recorded by a gage designed to provide a record of the peak stage reached in stream flow. If the response of the gage to such surface wave action was found to be slight, the Bureau recognized that the gage could possibly be used to record maximum stages reached by hurricane surges, The Hurricane Survey Coordinating Committee of the Corps of Engineers also felt that such a gage would be of considerable use in gathering hurri- cane and other storm surge data for design purposes, and was instrumental in having the tests continued with a modified gage. The gage initially supplied by the Weather Bureau was a U. S. Geological Survey river crest stage gage consisting of a 2-inch diameter plastic tube with a screw-on bottom cap having an effective bottom opening of 0,17 square inch, this opening being provided to allow an interchange of water between the outside and inside of the tube, The top of the tube was provided with a screw-on cap vented to permit escape of air. Inside the tube was a metal measuring stick which rested freely on the bottom cap, and extended nearly to the top cap. The inside of the tube had an effective area (pipe area minus rod area) of 3.07 square inches. In field operation, the tubing would be of ordinary 2-inch metal pipe and would be mounted to a pier, piling, tree, building, or other suitable structure. Plastic tubing was used for the tests to permit easy visual observation of the effect of wave action, -The crest stage in the field is recorded by means of a small quantity of ground burnt cork placed in the bottom of the tube. 28 As the water rises in the tube, the cork floats on the surface until the maximum stage is reached, As the water level starts to fall in the tube, a quantity of the burnt cork adheres to the measuring stick to leave a fairly permanent ring showing the maximum stage. The maximum stage may then be determined at any later date by removing the measuring rod and reading the level of the cork ring. In the Board's tests the tube was mounted over a small wave flume, the bottom end of the tube extending 0.7 foot below the water surface; the water was 1.25 feet deep. Waves were then mechanically generated in the flume, and measurements of the amount of rise and fall of the water level within the measuring tube were made visually against a scale marked on the tube. Wave charac-~ ‘teristics (height and period) were measured simultaneously using a standard two-probe resistance gage. A 1 on 6=slope, wave-absorbing, gravel beach was placed in the far end of the tank to prevent wave reflection. Wave periods tested in this tank ranged from 0.72 to 4.70 seconds, and wave heights from 0.03 to 0.70 foot. The measured values are shown in Figure 1 as a dimensionless plot of R/H vs H/T“ where R is the water level rise inside the tube above the still water level, H is the measured wave height, and T is the wave period, The parameter H/T” is essentially the deep water wave steepness (H /L_) being related by the equation H/T = (g/2n) (H/L_); it is used rather than the actual steepness values because of its greater simplicity in computation, Actual measured values of water level rise ranged as high as 0.24 foot. The plotted points show that the rise inside the tube varied from as little as one-tenth of the wave height for very steep short period waves to as much as 8 or 9-tenths of the height for lower steepness, longer period waves. The points were segregated as to wave period to see if this had an additional effect. As may be seen from Figure 1, actual period value appeared to have very little effect as long as it was above a value of slightly over 1 second; but for periods lower than this value an effect was observed, To further test the possible effect of wave period, and to ascertain the validity of the model tested, certain tests were also made in the large prototype tank of the Board in conjunction with other tests being performed there, A 9=foot long tube was obtained and mounted near the wall of this tank, and measurements were obtained for essentially prototype waves of 5.6, 7.9 and 11,3-second periods ranging in height from 1 to 6 feet, in a water depth of 15 feet, Measurements were again obtained visually by reading against a scale mounted on the tubing. Measured rises inside the tube amounted to as much as 2.5 feet for a 6-foot wave. These prototype measurements are also shown in Figure 1, They may be seen to fall in with the much smaller scale data obtained in the small wave flume; they consequently show very little wave period effect to exist, other than that taken into account by variation in wave steepness. 29 004 002 OO! -OO| al a = Wave Period el Wave Height (a) Symbol Wave Period (secs.) x 0.72 oo 1.00 6.5 ft. Ilsec, 1.55 1.63 2.63 3.65 4.70 NOTE: Symbol @ indicates data from large prototype tank. Nos. opposite plotted pts. indicate height and period of test wave. .002 004 .006 .008 0! 02 FIGURE |. WATER LEVEL RISE DUE TO WAVE ACTION FOR CREST STAGE GAGE WITH REGULAR OPENING 30 ERRATA SHEET for BULLETIN OF THE BEACH EROSION BOARD = VOL, 11, NO. 1, (JULY 1957) Page 30 = Figure 1 of article titled “Tests of River Crest Stage Gage Under Wave Action" = correct Ordinate scale for R/T values to range from 9,01 to 10,0 instead of 0,001 to 1,0, Wave Period Soon ela : |_| Poa eal me oe is 02 Symbol Wave Period O01 x 0.72 .008 1.00 1.55 1.85 2.63 .004 3.65 -006 4.70 oo2 |_ NOTE: Symbol ® indicates data from large prototype tank. Nos. opposite plotted pts. indicate height and period of test wave. 001 -OO1 J .004 .006 .008 .OI ® H R Walues equal to zero T2 FIGURE 2. WATER LEVEL RISE DUE TO WAVE ACTION FOR CREST STAGE GAGE WITH REDUCED OPENING 3| c Wave Crest Passing(Reduced Opening) d. Maximum Water Level Rise (Reduced Opening ) FIGURE 3. PHOTOGRAPH OF CREST STAGE GAGE ; IN LABORATORY WAVE TANK 32 The magnitude of the response inside the tube to the wave fluctuations outside was deemed excessive, as leading to appre- ciable error in actual field measurements. Accordingly the gage was modified to reduce the ease of water interchange between the outside and inside of the tube by reducing the effective bottom opening to 0.040 square inch. The measurements were then repeated with this reduced section, Values obtained are shown in Figure 2, As may be readily seen, they were reduced considerably, the ride-up inside the gage never amounting to more than a quarter wave height, and most being less than a tenth. The highest value observed for tests in the small laboratory tank was 0.05 foot (for a 0.56=-foot wave of 2,63-second period). For a number of test waves, parti- cularly with the shorter periods, no measurable rise was recorded. In the prototype tank in only one case did the ride=-up inside the gage exceed 0.3 foot (when it reached 0.5 foot for a 6-foot, 7.9-second wave) and most values were on the order of 0.2 foot, The general degree of reduction in ride-up inside the tube with the reduced opening is also indicated in the photographs in Figure 3, Pigures 3a and 3c show the gage as a wave crest passes by; note than while the original gage shows a water level rise of almost 0,1 foot (about one-third the wave height), the choked gage shows no rise, Figures 3b and 3d show the conditions at maximum water level rise inside the tube. For the original gage, this was 0.15 foot, as compared to only 0.02 foot in the choked gage. Note that, due to time lag in the response of the water level in the tube, the maximum rise always occurred considerably after the passage of the crest. The lesser response to wave fluctuations of the water level inside the tube with the choked down opening was considered much more acceptable, and it is believed that most field installations by the Corps of Engineers since these tests have utilized gages with the lesser size opening. The effective area of 0.04 square inch approximates that of a 7/32=-inch hole (0.038 square inch). Actually as many of the standard river crest gages supplied by the U, S. Geological Survey (through their Equipment Development Laboratory) come with a bottom-cap drilled with six 1/4-inch holes, a standard gage with five of these six holes closed up probably would give acceptable results for hurricane surge stage determination, Attention is called to the fact that a series of tests in Southern California ocean waters in the 1930's showed that if the bottom of the gage is continuously submerged, algae growth will close a 1/4-inch or smaller diameter hole, Holes of 1/2-inch in diameter were not closed by algae, however. Although the tests were made to determine feasibility of using the gage to give a measure of the maximum hurricane high water Stages, the results with the gage having the larger bottom opening would seem to indicate that the applicability of the general gage to measuring peak stream flood flows might also be reexamined to determine the possible effect of superficial wind waves and ship waves on these measurements, 33 PROGRESS REPORTS ON RESEARCH SPONSORED. BY THE BEACH EROSION BOARD Summaries of progress made during the past year on the several research contracts in force between universities or other institutions and the Beach Erosion Board,together with brief statements as to the status of some research projects being prosecuted in the laboratory of the Beach &rosion Board, are presented below, These summaries supple- ment and continue those contained in prior issues of the Bulletin, I. University of California, Contract DA-49-055-eng-8, Sources of Beach Sand. Seasonal sampling of Pt. Reyes beach and other beaches in the San Francisco area was continued. A report, “Changes in Configuration at Pt. Reyes Beach, California 1955-56" was published as Technical Memo- randum No. 91, The report summarized the sand sample data at Pt. Reyes over a year’s period, and presents one type of statistical analysis of the data, The report indicates that the beach is highly variable, with the sand ranging from relatively coarse in the fall to considerably less coarse in late winter, Also included in the report are data on the cut-and-fill of the beach area over a 23-year period. iit. Massachusetts Institute of Technology, Contract DA-49-055-eng-16, Sorting of Beach Sand by Waves. Additional data have been gathered on a flatter slope (1 on 25), particularly with regard to the incipient and equilibrium conditions and the mean net sediment velocity, primarily for waves in the 0.005 to 0.01 steepness range. A report on these tests is scheduled for sub- mission shortly. III, University of California, Contract DA-49-055-eng-17, Fundamental Mechanics of Sand Movement by Waves. Additional data on the flow pattern near the bed under oscillating wave motion have been gathered by use of an oscillating bed. These data have been used in conjunction with a theoretical analysis to define coefficients for a description of bottom flow conditions for turbulent flow for the case of small amplitude waves and relatively deep water; a report dealing with this work was published as Technical Memorandum No. 97. Iv. University of California, Contract DA-49-055-eng-31, Wind Action Over Shallow Water. Experimental work on the effect of bottom roughness in wind set-up and wave generation was performed using equally spaced strips of window screen serving to represent the roughness, Results of this study show 34 that the roughness increased the set-up over smooth bottom conditions by as much as two times when the water depth was slightly above the roughness top, though decreasing it to a negligible amount when the water depth was about half way up on the roughness strips. Wave heights were not appreciably affected for large depths over the roughness tops, but were reduced for small depths; generally wave heights could be pre- dicted adequately by using an “effective” depth equal to the depth over the roughness. A report was published as Technical Memorandum No. 95 of the Board, Funds for this study were provided by the District Engineer, Jacksonville, Florida. Vie University of California, Contract DA-49-055-eng-44, Laboratory Study of Wave Refraction. Refracted wave characteristics were measured in the mcdel tank for a series of wave, slope, and depth conditions, Measurements show that these conditions are being isolated. Data also shows that in general Snell*s law applies (even for a vertical discontinuity in slope), although for certain conditions the waves considerably over-refract. Wb Agricultural and Mechanical College of Texas, Contract DA-49-055- eng-45, Wave Statistics in *he Gulf of Mexico, Wave hindcast data were comple ed for five locations on the Gulf Coast for deep water and four shallov water depths (12,24,48, 96 feet) and were published as Technical Memor. nda Nos, 85-89 of the Board, Also published (Technical Memorandum No. 8) was a description of the methods used in obtaining the data for the shallow water locations. A detailed analysis of a number of the more severe hurricanes in the Gulf was also prepared, and by uSing an energy coefficient, the relative severities of most of the hurricanes of this half century were obtained and compared (Technical Memorandum No. 98). VII. University of Florida, Contract DA-49-055-eng-55. Analysis of Existing Data on Tidal Inlets, Available data on certain tidal inlets in the United States and a few foreign localities have been reviewed, A detailed analysis of this data has been made for the inlets where sufficiently detailed data were found to exist. The purpose of the analysis is to derive, if possible, a mathematical expression interrelating the variables which govern the cross-sectional area and controlling depth of an inlet. An interim report has been submitted and a report is being prepared for publication, This study is administered by the Beach Erosion Board for the Corps of Engineers" Tidal Hydraulics Committee, VIII, Agricultural and Mechanical College of Texas, Contract DA-49-055- Civ-eng-56-4, Estimation of Hurricane Surges. A method was devised for taking into account the effect of bottom roughness and the resultant bottom shear stress on the flow of water 35 into and through an estuary, and consequently the final water elevation around the shores of the estuary due to hurricane surge and for associated wind set-up (published in Technical Memorandum No. 93). Computations of surge distribution in Narragansett Bay have been made by applying this method using IBM computers, for several design hurricane conditions, These in turn are being utilized in conjunction with tests underway at the Waterways Experiment Station to obtain design criteria for the New England Division, IX. Dr. W. C. Krumbein (Consultant). Study of Beach Sampling Methods. A report was published (Technical Memorandum No. 90) comparing a number of (beach) sampling designs to indicate the factors involved in beach sampling for different purposes. In addition, data were obtained and analyzed on the behavior of artificially placed material in beach fill and nourishment projects to determine or verify design criteria for artificially placed beach material. Xe Waterways Experiment Station, Corps of Engineers. a. Study of Interrelation of Tidal Iniets and Adjacent Beaches. Testing was continued, expanding on studies made in previous years. A report was prepared (Technical Memorandum No. 94) describing the test results, primarily of two similar tests, one with a relatively deep lagoon and the other with a shallow lagoon. In both cases a down-beach inlet migration occurred, but where breakthroughs of the outer bar occurred several times with the deep lagoon, none occurred with the shallow lagoon until one was forced by superimposing a storm tide con- dition on the model. This study is supported jointly by the Beach Erosion Board and the Corps of Engineers Tidal Hydraulics Committee. b. Study of Durability of Concrete. A report summarizing the factors affecting concrete durability in Coastal Structures was published in Technical Memorandum No, 96, The publication also reports on the results of tests of specimens, and selected service records of specific prototype installations. XI. Dr. John H. Davis - Contract for Study of Dune Stabilization. A report on the study of shore protection by vegetation and planting on coastal dunes has been prepared and will be published as a Technical Memorandum, The report summarizes the mechanics of dune formation and the stabilization of these dunes by plants in the various coastal regions of the United States. It also presents data on the history of several continuing efforts to stabilize dunes by plants. 36 XII. Beach Erosion Board Staff. (a) Wave Forces on Piles Numerous measurements have been made of the wave forces on a vertical 12-inch pile with a 3-foot sensitive (instrumented) section. The pile is cantilevered from a frame at the top of the tank and may be raised or lowered to place the 3-foot sensitive section at various heights. Waves with periods ranging from 5 to 16 seconds, and heights ranging from 2 to 6 feet have been tested in water depths ranging from 7 to 15 feet. The forces on the 3-foot sensitive section ranged from 20 to 100 pounds for nonbreaking waves, and breaking waves produced forces of short duration as high as 1,000 pounds, (b) Wave Run-up Testing of eight smooth slopes ranging in steepness from 1 on 30 to a vertical wall has been completed and most of these slopes have been tested for the effect of roughness on wave run-up by roughening the slopes with five sand sizes ranging from 0.2 to 10 millimeters in median diameter, Also, most of the slopes have been tested for the effect of permeability op wave run-up for the same sands used in the roughness tests, The data show that slope roughness and permeability reduce wave run-up considerably below that observed for smooth slopes. (c) Study of Sand Bypassing Operation at Port Hueneme As a continuation of the observational program, a survey of the area wasS made in May 1957. The data taken before, during and after the Port Hueneme dredging to June 1955 have been analyzed and the report was published as Technical Memorandum No. 92. Computations to establish the volumetric changes between June 1955 and June 1956 have been made and according to these computations, over 2 million cubic yards of material was lost from downcoast beaches while the upcoast area gained in the order of 200,000 cubic yards of materia]. It is recognized that the major portion of the material from updrift is shunted into Hueneme Submarine Canyon by the west jetty and lost from the survey record. (d) Laboratory Study of Effects of Groin Field on Littoral Drift Passing Field Preliminary tests were made in the Shore Processes Test Basin to establish an equilibrium profile on which the groins will be placed. Installation of a new trapping and sand=moving system using eductors to transfer the trapped sand to the feeder beach area was completed. The new system has been used in several tests and works very well. (e) Measurement of Suspended Material in Laboratory Wave Tanks Sampling has been continued in the Shore Processes Test Basin (groin study) and the large outdoor wave tank. Analysis of the data is in progress and a draft of the report is being prepared, oi (f£) Wave Forecasting Methods of forecasting for shallow water wave generation have been presented in Technical Memorandum No. 84 "Wave Forecasting Relationships for the Gulf of Mexico", Procedures include taking bottom friction into account, Formulas and techniques used are calibrated with respect to hurricane wind and wave data from Lake Okeechobee, Florida and some wave data for lighter winds of the Gulf of Mexico. Analysis and comparison of the Bretschneider revised Sverdrup- Munk method with the spectrum method developed by Neumann and Pierson are being continued in an attempt to reconcile the two methods and establish more accurate values of the exponents used in the two methods, The development of a joint distribution function for height and length, converted to a joint distribution function for height and period has been in progress, From this distribution function, a general form of the wave spectrum is being studied. A report on the above will be issued in the next year. (g) Equilibrium Profile Tests Equilibrium profiles were obtained in the prototype tank for the following wave conditions: Wave Height Wave Period 5.5 feet 11.33 seconds Sie) 5.60 5.0 B55 2.9 16.0 5.3 16,0 Most of these wave conditions were also tested in the small wave tanks at 1:10 and 1:15 scales. The resulting data are to be used to establish profile scale relationships in movable bed beach models. A paper was prepared covering the results of the tests and is to be given at the meeting of the International Association of Hydraulic Research in Lisbon, Portugal. (h) Hurricane Studies The staff of the Board had been called upon to support the present hurricane study program of the Corps of Engineers, Considerable work has been done by the staff in developing and improving methods for estimating storm surge heights and wave heights under a variety of shoreline conditions, Wave forces and wave overtopping phenomena con= nected with seawall and dike design have also been studied. 38 (i) Recorded Wave Characteristics Routine compilations were made of recorded wave characteristics at: Huntington Beach, California; Daytona.Beach, Florida; Clearwater Beach, Florida; Palm Beach, Florida; Evanston, Illinois. (j) Sand Movement Study at Moriches Inlet, Long Island, N. Y. The report on sand movement at Moriches Inlet is being edited for publication, (k) Reexamination of Beach Pill Projects This includes a continuing program of reexamination of artificially nourished beaches to determine the effectiveness of the fill material within the beach zones, and to better establish the factors upon which to base the design characteristics of fill material. Reexamination report of a project at Virginia Beach, Virginia has been completed and is being edited for publication as a Technical Memorandum, Reexamination is now under way of projects at Plum Island, Massachusetts, West Haven, Connecticut and Presque Isle, Pennsylvania. (1) Technical Report No. 4, “Shore Protection Planning and Design" This involves a continuing study to improve and supplement present chapters of this publication. General corrections and addenda have been completed and will be disseminated when printed. Pertinent data from the Technical Memoranda on durability of concrete in coastal structures (TM 96) and on stabilization of dunes by vegetation will also be incorporated into Technical Report No. 4. (m) Regional Studies Data on the geomorphology and characteristics of littoral materials similar to that compiled for the Delaware Coast are being compiled for the South Shore of Long Island and being completed for the shore sector from Cape Henlopen, Delaware to Cape Charles, Virginia. XIII, Publications Technical Memoranda published by the Board to date are listed below. Those designated with an "x" are out-of-print, but others can be furnished on request to persons within the United States, 39 Title and Date A Model Study of the Effect of Submerged Breakwaters on Wave Action, 1940 Abrasion of Beach Sands, February 1942 Shore Processes and Beach Characteristics, May 1944 Surface Features of Coral Reefs, May 1944 A Wave Method for Determining Depths Over Bottom Discontinuities, 1944 An Ocean Wave Measuring Instrument, October 1948 ShoreCurrents and Sand Movement on a Model Beach, September 1944 Depths of Offshore Bars, July 1945 Proof Test of Water Transparency Method of Depth Determination, July 1948 Experimental Steel Sheet Pile Groins, Palm Beach, Florida, 1948 Reflection of Solitary Waves, November 1949 Durability of Steel Sheet Piling in Shore Structures, February 1952 Longshore Current Observations in Southern California, January 1950 Report on Beach Study in the Vicinity of Mugu Lagoon, California, March 1950 Longshore Bars and Longshore Troughs, January 1950 Accretion of Beach Sand Behind a Breakwater, May 1950 Test of Nourishment of the Shore by Offshore Deposition of Sand, May 1950 Rayleigh Disk as a Wave Direction Indicator, July 1950 Submarine Topography and Sedimentation in the Vicinity of Mugu Submarine Canyon, California, July 1950 Beach Cycles in Southern California, July 1950 The Interpretation of Crossed Orthogonals in Wave Refraction Phenomena, November 1950 The Source, Transportation and Deposition of Beach Sediment in Southern California, March 1951 The Use and Accuracy of the Emery Settling Tube for Sand Analysis, May 1951 The Accuracy of Present Wave Forecasting Methods with Reference to Problems in Beach Erosion on the New Jersey and Long Island Coasts, April 1951 The Slope of Lake Surfaces Under Variable Wind Stresses, November 1951 Sand Movement on the Shallow Inter-Canyon Shelf at La Jolla, California, November 1951 Wind Set-up and Waves in Shallow Water, June 1952 Sources of Beach Sand at Santa Barbara, California, as Indicated by Mineral Grain Studies, October 1952 Artificially Nourished and Constructed Beaches, December 1952 Annotated Bibliography on Tsunamis, February 1953 Laboratory Study of Wave Energy Losses by Bottom Friction and Percolation, Pebruary 1953 x Qut-of