Sam Rayburn Reservoir

The Sam Rayburn Dam and Reservoir was constructed by the U.S. Army Corps of Engineers, Ft. Worth District in cooperation with the Lower Neches Valley Authority (LNVA) of Beaumont.  It was designed to control floods, generate hydroelectric power and conserve water for municipal, industrial, agricultural, and recreational uses.  Construction began in 1956 and deliberate impoundment of water began in March 1965.  The estimated cost, including development for public use, is $66 million.  With a flood control storage of 1,145,000 acre-feet, it is estimated that annual benefits of $4,958,000 result from the operation of Sam Rayburn Reservoir due to the control of floods, conservation of water for various purposes, generation of power, and the preservation of fish and wildlife.

At the Angelina & Neches River Authority (ANRA), the primary association with the Sam Rayburn Reservoir has been the On-site Sewage Facilities (OSSF) Control Zone Program initiated in September 1972 by the Neches River Conservation District (NRCD).  Once ANRA was formed in 1977, the program continued and ANRA established a water quality presence at Sam Rayburn to protect the reservoir from wastewater discharges due to the absence of or defective on-site wastewater systems.  The effort through the years to establish this program has been successful.  The current license total in the ANRA on-site system database is approximately 4,200.  These licensed systems are on file and known to exist by ANRA.  Through the years, many of the systems changed ownership, were replaced by new systems, or were modified.  It is estimated that 4,200 on-site systems in approximately 141 subdivisions are located in the five county regulated zone (an area within the Sam Rayburn Reservoir watershed lying between the take line or 171-foot contour and a line parallel to it 2,000 feet from the take line).

The current ANRA Order for the Sam Rayburn Reservoir control zone was approved by the Texas Commission on Environmental Quality (TCEQ) and issued to ANRA on April 3, 2000.  This Order authorizes ANRA to regulate on-site sewage facilities (OSSF) pursuant to Chapter 366 of the Texas Health and Safety Code and Texas Administrative Code (TAC) Title 30: Environmental Quality, Chapter 285. 

Water Quality at Sam Rayburn Reservoir

Sam Rayburn Reservoir (Segment 0610) is classified by the TCEQ as water quality limited and the designated water uses are Contact Recreation, High Aquatic Life Use, and Public Water Supply.  There are 29 wastewater dischargers in this segment (16 municipal, 13 industrial) with a combined total discharge of approximately 22.54 MGD.  The elevations range from 530 feet MSL to 164 feet MSL at the reservoir power pool.  The principal tributaries of the segment are Attoyac Bayou (segment 0612), Ayish Bayou, Carrizo Bayou, Mill Creek, and Harvey Creek.

The 2000 Texas Water Quality Inventory prepared by the TCEQ pursuant to Section 305(b) of the Federal Clean Water Act summarizes the general use support and water quality concerns for the Sam Rayburn Reservoir.  The contact recreation use and public water supply use are both supported for the reservoir, however the aquatic life use is not supported in several areas.

These areas include 5,120 acres at the upper end of the Angelina River arm downstream of Paper Mill Creek.  The aquatic life use is partially supported in five other areas, due to depressed dissolved oxygen concentrations.  In three acres at the extreme upper end of the Angelina River arm upstream of Paper Mill Creek, the aquatic life use is not supported because of sub-optimal fish community characteristics.  The aquatic life use is partially supported in 5,120 acres in the middle portion of the Angelina River arm near SH 103 because dissolved aluminum concentrations exceed the acute aquatic life criterion at a 25% frequency. 

The fish consumption is partially supported throughout the reservoir because of a restricted fish consumption advisory issued by the Texas Department of Health in November 1995 due to elevated levels of mercury in fish tissue.  General uses are partially supported in the main body of the reservoir near SH 147 because pH values are outside the criterion range. 

Dissolved oxygen is an aquatic life concern in the Attoyac Bayou arm near SH 103.  Oil and grease, arsenic, manganese, and nickel in sediment are concerns at numerous locations throughout the reservoir.  Ammonia-nitrogen and orthophosphorus are concerns at several locations throughout the reservoir.  In the upper end of the Angelina River arm, water color and odor are concerns.