Texas Freshwater Fisheries Center (Athens TX): Water Improvements

SPI, under contract with TPWD, was assigned this project at the Texas Freshwater Fisheries Center near Athens, Texas. The project had some interesting features and required some complex design from the SPI not usually found in our typical projects. Construction also presented some challenges. Construction was completed at a cost of $2,1 million. Heavy winter and early spring rains have delayed completion of the project. The project consists of construction of a new storage reservoir, restoration of two ¾ acre effluent ponds, and construction of a new 18” recirculation line and new wet well.

The new four surface acre reservoir provide a storage buffer for the Center’s hatchery operations and visitor’s center. Previously, water was pumped from Lake Athens to a small divider box where non-potable supply water is then distributed to the hatching ponds and visitor center. Pumps ran constantly. Construction of the new reservoir would provide protection for supply in case of mechanical failure of the pumps. The reservoir included screening structures, an outlet control structure, aeration facilities, and concrete cleaning ramp structures.

The reservoir included concrete screening, outlet, aeration, and cleaning ramp structures. Over 160,000 square feet of geo-membrane liner was specified for covering the bottom and interior slopes of the pond. A floating baffle was included to direct water around the pond to improve aeration and sediment control. Due to sandy on-site soils, interior reservoir slopes were plated with a clay liner.

The existing effluent ponds at the TFFC needed restoration as well. Deposited sediment and old geo-membrane liner were removed, the pond earthwork reshaped, and 55,200 square feet of new geo-liner installed. Because the hatchery could not operate without the use of one of the ponds, the pond restoration work was phased to allow by-pass of one of the ponds while the other was restored and vice-versa. In conjunction with this work, 1,225 LF of 18” C900 PVC pipe was installed to provide the Center with the ability to recirculate up to 100% of the effluent from the hatching ponds. Before the new system, effluent was returned to Lake Athens via a natural stream. A new Parshall Flume was included in the design to measure amounts recirculated. An existing Parshall Flume measures return flow to Lake Athens per the Center’s agreement with the Athens Municipal Water Authority and the TCEQ.

Finally, a new wet well intercepts the recirculation flow near the existing pump station to introduce supply back into the system at the Center’s option. The new wet well consists of a 5’ x 5’ x 21’ deep concrete structure. One challenge during design and construction was bringing the lake supply water on-line with the new wet well as it heads to the existing pump station. Divers were enlisted to provide a temporary cut and plug to the supply line to allow for connection of the line to the wet well. A total upgrade of the Center’s SCADA system has been added to the project by change order.