The Lake Travis vicinity lies predominantly within a carbonate rock terrane and is the site of ongoing intensive residential development. Such development may impose adverse environmental effects such as upland erosion, rapid infilling of the lake with sediment, and the ultimate lowering of surface- or ground-water quality. Furthermore, inhabitants may be subjected unwittingly to geologic hazards such as flooding or mass wasting.

Historical monitoring in the vicinity of the Brazos River delta (San Luis Pass to Brown Cedar Cut) records the nature and magnitude of changes in position of the shoreline 'and vegetation line and provides insight into the factors affecting those changes.

The public tends to dismiss floods as somewhat unreal catastrophes or occasional inconveniences that usually affect others. When a flood disaster strikes at the local level, the magnitude of the event is appraised in terms of the damage to human works on the river-valley floor or, in some cases, in terms of the loss of life. Resources are mobilized to combat the disaster, and discussions ensue concerning flood control plans and projects.

Change, both natural and man-induced, is a significant and defining element of the Coastal Zone. Man-induced change, by definition, can be controlled if desired. The work of nature, however, is altered and modified with much more difficulty, if at all, and attempts to do so commonly lead to unintended results. Prudent use and adequate management of the Coastal Zone must consider natural changes.