waves was greater than could be removed from the inlet by the tidal currents. 
2. Wave Run-Up on Shore Structures - Preparation of the first interim 
report, a revised testing program, and cost and time estimates were completed 
and forwarded to the Beach Erosion Board. Testing was deferred pending ap- 
proval of the revised testing program and cost and time estimates. The results 
of tests described in the first interim report (test data for a vertical-faced 
monolithic seawall) show that the volume of overtopping water and height of wave 
run-up vary with both wave height and length. The variation is discontinuous. 
The volume of over-topping water and height of wave run-up vary in cycles from 
minimum to maximum and increase as wave height and wave length increase. 
Ve Beach Erosion Board, Research Division, Project Status Report for 
Quarter ending 31 December 1952. 
In addition to the research projects under contract to the various 
institutions which are reported on above, the Research Division of the Beach 
Erosion Board is carrying out certain projects with its own facilities. The 
main projects were described in the last Bulletin (October 1952) and a short 
description of the work accomplished through the last quarter is given below. 
Study of Effects of Tidal Fluctuations on Wave Produced Beach Profiles - 
The priority projects which had interrupted work on this project have been 
completed, and the 85 foot concrete indoor tank is being converted back to its 
original condition for the completion of these tests, The resumed test 
schedule will nee the remainder of tests for a l-hour tidal cycle with 0.50 
and 0.25 feet tidal range; thereafter eetne will be made on l-hour tidal 
eycles with 0.50 and 0.28 feet tidal range 
Stag of Quantity of Sand in Suspensibn in Coastal Waters (in two 
i 
ta 
Part 1. Laboratory development of a suspended sediment sampler for use 
in studies of sand transport by wave action - The report on this phase of 
study has been completed and is under review for possible publication. 
Part 2. Field investigation of suspended sediment in surf zone at 
Mission Bay, California - The report on this field investigation has been 
completed and is under review by the staff. A suspended sediment sampler, 
auxiliiary parts, instructions for operation and maintenance, etc., were 
shipped te Scripps Institution of Oceanography for use on similar work. 
Correlation of Effectiveness of South Lake Worth (Florida) Inlet By- 
Passing Plant with Rate of Drift Reaching Plant - The field data on this* 
study are being analyzed and areport is in preparation. Preliminary analysis 
of a portion of the collected data indicates that a relationship between 
wave energy and material pumped by the by-passing plant can be developed 
for the period of observation. The procured sand samples are being studied 
in an effort to correlate the material movemant with sediment characteristics. 
44 
