individuals or corporations on South Padre Island, North Padre Island, and Sargent Beach 

 (Figure I) have completely failed or have been so severely damaged that costly repairs 

 were required to maintain them. A representative example is found on South Padre 

 Island (Figure 5) where a privately built seawall constructed in 1962 was destroyed by 

 Hurricane Beulah in 1967. This seawall was built by the landowner after a previous 

 seawall, constructed seaward, foiled in the early I960's. The position of the former 

 seawall is now completely submerged by the open gulf. Furthermore, continued erosion 

 has removed the beach in front on the second seawall (Figure 5). 



The most recent examples of extensive seawall damage occurred on North and 

 South Padre islands during Hurricane Allen (1980). The fact that a large seawall built 

 with corporate funds did not survive the storm (Figure 6) is important for several 

 reasons. First of all, the seawall failed even though (I) the storm center was more than 

 130 km (80 mi) away and (2) at landfall the storm was relatively weak by hurricane 

 standards. Secondly, considerable damage occurred on the landward side of the seawall 

 owing to overtopping by storm waves and the hydrostatic head (back pressure) developed 

 by flood waters as the storm surge subsided. Thirdly, this massive and expensive 

 structure needed extensive repairs less than 15 years after it was built to protect a 

 resort development. 



Figure 6. Seawall on North Padre Island damaged during Hurricane Allen, 



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