There has only been one major rain event since Eddie Joseph Memorial Stadium was available for public use and Wharton’s Lake Nett residents were affected by flood waters.
Those complaints came to a head several months ago during a meeting when dozens of concerned Lake Nett residents met with city, school, and county officials at Wharton City Hall.
Recently, the Wharton Independent School District introduced a question and answer sheet regarding the stadium storm water drainage. The Q and A sheet was produced as a result of the Sept. 23 meeting.
According to Wharton ISD, it is very likely that the body of water that is in Lake Nett “could reach capacity during an extended period of heavy precipitation or during an extreme event such as a hurricane.” The sheet also explains that the pond could reach capacity if the level of Lake Nett does not allow an WISD official to pump additional water into the lake. The question was the fifth of six on the sheet.
The sixth asks what happens to any additional runoff from the site should the detention pond be full, and the answer was “the north bank of the detention pond is designed to function as an overflow for the pond should the pond reach capacity. Water exiting the pond through this overflow would sheet flow to the north and into Cat Island Slough.”
The second question asks what type of pond WISD constructed on the stadium site.
It read that the construction team of WISD comprised of RWS Architects, Brooks and Sparks Engineering, and the CMAR for the project Polasek Construction all determined that the most efficient system for the district to use that meets the requirements of the City of Wharton is the water detention system.
“The decision was made with student safety as the priority and that other considerations were the economics of maintenance and site aesthetics,” WISD concluded in its answer.
WISD said there is a difference between a retention and detention pond, with the latter being what was constructed on the stadium site.
“Retention ponds maintain a pool of water throughout the year and hold storm water runoff following storms; detention ponds hold water for a short period,” WISD said. “This pond temporarily holds water before it enters the outflow that is assigned to receive the runoff.”
At the meeting, Lake Nett residents were told by WISD’s Mike Lanier that by law, water cannot leave a developed site at a rate greater than it did prior to construction.
WISD has said that the five-acre detention pond (10 feet at the shallow end to 15 feet at its deepest end) is part of a large underground pipe manifold system that covers the entire 25 acre developed site.
“The total capacity of the system, including the pond and the underground pipe manifold system is slightly more than 31 acre feet of storage. “This number exceeds the capacity required by the City of Wharton,” WISD said. “Water from the site is captured by a series of drains connected to the manifold system and is moved to the detention pond before it is allowed to exit the property.”
The last question was where does the water go after it enters the pond?
The pond is designed to be drained by an automatic pump system (consisting of three pumps) that would remove water as a rate not to exceed 863 gallons per minute. These pumps move water from the pond into a 10-inch pipe that is connected to an existing 16-inch pipe under Lakeshore Drive that allows water to flow into Lake Nett.
“A float system controls the activation of the pumps. The pumps would be automatically turned on as Lake Nett is capable of handling additional water and turned off when the level of the lake reaches the predetermined stage. The levels for turning the pumps on and off are approved by Jones and Carter, which is the city’s engineer. WISD has the ability to manually turn off the pumps if necessary.