X
GO

RESERVOIRS: STORING DURING WET TIMES TO HELP IN DROUGHT

With the ongoing exceptional drought, it would probably surprise no one that water levels are falling steadily at the 11 reservoirs in the Brazos River basin.

For those who live next to or like to visit one of these lakes and have seen water being released from the dam, you might wonder, “Why in the world are you letting out water from the lake when the level is already so low?”

This is a question posed often to the staff at the Brazos River Authority. After all, the lakes are popular destinations for many recreationists, from boater to anglers to families enjoying a weekend camping and swimming trip.

To answer the question, one must first understand that the reservoirs in the Brazos River Authority system were built for water supply and flood control. While we enjoy many recreational benefits from the reservoirs, recreation is not their primary purpose. The lakes are not designed to remain at a constant level but are rather part of a dynamic system.

The concept behind a water supply reservoir is to capture and store water during wet times for use during periods of droughts when rainfall and river flows are down. It might help to think of the lakes as massive storage tanks with an added recreational benefit. When the weather is kind to us and the lakes are full, they are great spots to go and have fun. But when Texans get thirsty, these tanks are ready to swing into action and send water their way. That makes them all the more vital in times of severe shortage, when other local water sources begin to dry up.

The current drought provides a good example. All of Texas, including the Brazos River basin, has seen unprecedented rainfall shortages over the last ten months, with some areas more than 20 inches below normal amounts. Add to this the large-scale evaporation caused by the string of record high temperatures and the drought quickly takes a toll on Texas water supplies.

Currently, there is little, if any water flowing into the reservoirs. In fact, the Brazos River upstream of Possum Kingdom Lake is entirely dry. So imagine that the reservoirs did not exist today. Those that rely on the rivers’ flow for drinking water would literally be left “high and dry.”

Following the drought of the 1950 the US Army Corps of Engineers and state organizations such as the Brazos River Authority, built numerous reservoirs for both flood control and water supply. The stored water in the reservoirs provides access to water supply even in these exceptional drought conditions.

During drought and when water supply is needed, the reservoirs are able to release water to flow downstream to those in need. Releases from these reservoirs also provide environmental benefits. The current flow of water on the majority of tributaries.