estimated wave heights were given in Brower, et. al., (1972) as

In the Galveston area, waves greater than 11 feet have been observed

for all months of the year. Heights of 20 feet or greater have been observed from September to April and in June (Brower, et. al., 1972). In general waves are not as high during the summer months when average wind speeds are less. An average wind speed of 11.7 knots for the Galveston area usually results in approximately 5 foot waves. Statistical estimates of wave heights were given in Brower, et. al., (1972) as follows:

Mean Recurrence Interval 5 yr 10 yr

50 yr

25 yr

D. The Biological Environment and Communities of the Coastal Zone

The boundaries of the area to be discussed are roughly

of coastline from 93°10' to 96°40' west longitude and from about 20 feet above MSL to mean high tide.

the arc

The coastal zone includes bays, salt marshes, estuaries, barrier islands, beaches, and upland prairies and wooded lands. The entirety of the coastal zone is contained in the botanical province known as the Gulf coast Prairies and Marshes which, according to Suter (1971) is a nearly level plain, slowly drained, and less than 150 feet in elevation, with numerous sluggish rivers, creeks and bayous and other waterways. It is characterized by level grass lands that support ranching and farming, by low woodlands primarily along streams, and by wetlands. The climax vegetation of the Gulf Prairies is largely southern cordgrass prairie and bluestem sacahuista prairie or post

oak savannah. However, in Texas, much of the area has been invaded by trees and brush such as mesquite, oaks, prickly pear, and several acacias. Woodlands along streams and wetlands may consist of pine, willow, ash, cottonwood, live oak, bald cypress, and others. Vegetation of the coastal zone is indicated in Figure 13, a-d.

The following pages include brief discussions of the estuaries and several represent transects along the coast.

1. Sabine Lake 1/

Sabine Lake is a shallow estuary that lies on the Texas

1/

Information sources:

Stevens (1960a, b, c, 1962).

Figure 13.

Simplified Illustration of the Natural Vegetation of the
Upper Texas Coastal Zone (From Fisher et. al., unpublished
draft, Beaumont-Port Arthur Sheets - Environmental Geologic
Atlas of the Texas Coastal Zone; Fisher et. al., 1972;
Texas A & M Univ., 1972)