plan test than during the base test. Subsequent analysis of the data by 

 the Environmental Protection Agency (EPA) indicated that, because pollut- 

 ants actually decay with time, water quality in the area would actually 

 be improved as a result of the delay in arrival time. The substantial 

 reduction in pollution from local sources is caused by pollutants flow- 

 ing out through the new inlet during ebb currents but not completely 

 returning during the subsequent flood currents; thus, the rate of flush- 

 ing of such pollutants is much faster with the new inlet in place. In 

 summary, the new inlet would reduce pollution concentrations in the study 

 area from all of the three principal sources. 



It is emphasized that the actual test data obtained from the model 

 were very comprehensive in nature. Tides, current velocities, and 

 salinities were measured at hourly intervals or less over complete tidal 

 cycles at many stations throughout the study area, and current velocities 

 and salinities were measured at several points in the vertical at each 

 station. In the dye-tracer tests simulating pollutants, surface and 

 bottom samples were obtained for analysis at more than 100 stations in 

 and adjacent to the study area. Time-exposure photos showing surface cur- 

 rent patterns and velocities were obtained at hourly intervals throughout 

 the tidal cycle in the new inlet and in all adjacent areas where flows 

 could be affected by the new inlet. All of these test data were furnished 

 to Federal, State, and local agencies concerned with the effects of the 

 inlet on the water quality. 



i. Hurricane Surge Protection — Galveston Bay . 



(1) Project. Construction of a hurricane surge protection 

 barrier. 



(2) References . Marines and Woodward (1968); Reid and Bodine 

 (1968); Brogdon (1969); Bobb and Boland (1970a, 1970b); Sager and McNair 

 (1973a, 1973b); and Section VII, 8, b of this report. 



(3) Laboratory . WES (physical models); U.S. Army Engineer Dis- 

 trict, Galveston, and Texas A§M University (mathematical model). 



(4) Test Period . January 1965 to April 1970. 



(5) Problem . The Texas coast frequently experiences hurricane 

 surges; therefore, consideration had to be given to protection of this 

 area from inundation resulting from storm surges. A long-range plan was 

 developed by the U.S. Army Engineer District, Galveston, to investigate 

 the feasibility of construction of such protection with the initial effort 

 directed toward the problems surroionding the Galveston Bay complex. The 

 design of an adequate protection system involves not only reducing water 

 heights resulting from hurricane surges, but many other factors such as 

 salinity conditions in the bay, effects of the plan on flushing and cir- 

 culation characteristics, fish and wildlife, navigation requirements, and 

 flooding of the bay during periods of high upland discharge. 



(6) Purpose of Model Study . The physical model studies were 

 conducted to (a) determine the effects of all proposed structures on 



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