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FYI
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For more detailed information on erosion response activities, see the General Land
Office's (GLO) 1996 Texas Coastwide Erosion Response Plan: A Report to the 75th Legislature and Dune Protection and Improvement Manual for the Texas Gulf Coast.
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Shoreline erosion is an issue of economic and environmental concern on the Texas
coast. Erosion, caused by both natural and human actions, results in the loss of beaches, coastal highways, residential and commercial structures, and wildlife habitat.
Several factors can determine the amount of erosion that takes place on a given beach:
wave energy might remove more sediment from the beach than is "supplied by longshore currents"; human-made structures, such as jetties, and coastal dredging can
affect the amount of beach sediment; and droughts and other climatic occurrences might determine the amount of sediment brought to the beaches by rivers.* The economic and environmental costs of erosion have prompted action at local, state, and
federal levels. To slow down erosion, some states have required set-back rules, which prohibit construction of buildings and homes so many feet onto the beach, and some
communities have prevented "hard structures" like jetties.
It has been estimated that more than 27,000 acres of gulf shoreline were lost to erosion from the mid-1800s to 1982.* Erosion rates vary up and down the Texas coast from an average of 24 feet per year at Sargent Bay to 7 feet per year at South Padre Island.* According to the University of Texas Bureau of Economic Geology, where there has been
human modification (residential and commercial development, jetties, dredging) along the Texas Gulf Coast, the rate of shoreline erosion has accelerated.*
The causes of bayfront erosion are different from the causes of gulf shore erosion. Within the bay system, which is
considered more complex than the gulf shore system, erosion is caused primarily by human actions, particularly the
subsurface withdrawal of groundwater and oil and gas. Texas bay shores are eroding at rates that vary from 1 to 10 feet a year.*
According to the Texas General Land Office, an effective response to the problem of coastal erosion is thwarted by the
lack of economical sand sources for replacement sediment and by poor coordination among federal, state, and local agencies.* The GLO does not point to the lack of controls over residential or commercial development, though other
coastal experts do.
State guidelines for responding to coastal erosion for the most part recommend "soft" remedies, such as establishing
shoreline vegetation, providing beach nourishment, and rebuilding dunes, rather than erecting permanent structures.
Hard structures such as seawalls and bulkheads erected by property owners can accelerate erosion and damage
neighboring properties. In Galveston Bay, where shoreline loss has been about 2.2 feet per year, specific grasses are
being planted at various sites, and wave barriers made of used parachute material are being used to protect the new plantings.*
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