Galveston District holding back water in Addicks & Barker Reservoirs for outflow measurements tests

U.S. Army Corps of Engineers Galveston District
Published Nov. 22, 2021

The U.S. Army Corps of Engineers (USACE) Galveston District, in coordination with the United States Geological Survey (USGS), will close the Addicks and Barker reservoirs for varying periods to obtain a specific non-flooding pool elevation to take flow measurements through the new outlet structures.

A new outlet structure at Barker Dam was put into operation on February 14, 2020, and a new outlet structure at Addicks Dam on March 24, 2020. The closures will allow the Galveston District to take field measurements that will be used to validate and calibrate the outflows from the dam’s new outlet structures when the pools inside the reservoirs are at various elevations. The tests will ensure the dams are in compliance with USACE policy for the operation of both dams. 

The testing is tentatively scheduled to occur sometime between late-November 2021 to January 2022. The extended period of time is required to generate the desired pool elevations within each reservoir: approximately 49 days for Addicks to reach an elevation of 90 feet and 39 days for Barker to reach an elevation of 87 feet. Once the optimal pool elevations are reached, both reservoirs will drain for a period of 7-10 days to measure outflows.

The reservoirs will be closed one at a time, starting with Barker Reservoir. USACE Dam and Levee Safety staff will be monitoring the reservoirs during this time to ensure there is no risk to the reservoirs. Flows downstream of the reservoirs may be slightly reduced because only one reservoir will be releasing; however the Buffalo Bayou Watershed will not be impacted.

USACE Water Management will monitor the weather continuously and a contingency plan is in place in the event the Greater Houston Metro Area receives excess rainfall during the testing period. Additionally, should sufficient rainfall occur during the testing period, the time needed for the reservoir closures may be shortened.

During the reservoir closures some trails will not be accessible at Barker Reservoir. Additionally, Patterson Road, Bear Creek Agrilife Center and some areas nearby may be impacted at Addicks Reservoir. 

The Addicks and Barker dams and reservoirs are federally funded and operated projects located adjacent to each other on the upper watershed of Buffalo Bayou. The dams were constructed in the 1940s in response to damaging floods on Buffalo Bayou that struck Houston in 1929 and 1935. They are designed to collect rainfall and release that rainfall down Buffalo Bayou at a controlled rate that reduces risk of flooding in downtown Houston and the urban areas west of downtown.

For more news and information, visit our website at or visit the Addicks and Barker Facebook page at

SWG Public Affairs
2000 Fort Point Road, Galveston TX

Release no. 21-021