Instream Flow Studies

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Instream Flow Studies

Instream Flow Studies

Did you know that the banks and areas around our waterways are just as important to the health of our drinking water as the water itself? The Brazos River Authority studies the changes at eight sites across the Brazos River basin. Fluctuations to instream biological communities, including fish, aquatic insects, freshwater mussels, and aquatic vegetation are documented, as well as changes in the riparian zone to the tree community, bank shape, and sediment deposition.

Sometimes called a stream or riverbank, the riparian zone is the vegetated area between the river or stream and the higher ground. In the riparian zone, water, soil and vegetation interact. Healthy riparian zones also provide habitat for both aquatic and land species. One of the key components of a healthy stream is a healthy and intact, undisturbed zone of native vegetation.

These assessments help to establish a baseline dataset or the current health of the area for environmental conditions. The assessments also monitor current conditions and provide information that serves as a basis for future water management decisions.

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The Brazos River watershed crosses eight ecoregions and seven climate zones ranging from the semi-arid area near the city of Lubbock to the subtropical zone near the Gulf of Mexico. Because of this, the basin is home to a broad ecological community, including many different types of water and land-based plants and animals that rely on a sufficient amount of healthy water moving through the system.

At these sites, the BRA team collects data on fish and benthic macroinvertebrates (aquatic insects and freshwater mussels), as well as data on their instream homes. The team also conducts surveys of the plants and trees that grow along the banks. They study the watercourse’s channel and conduct sediment sampling of the dirt and sand in the stream or riverbed to assess how various streamflow conditions affect the amount and diversity of the plants and animals that are dependent on the stream.

This data allows us to make sure we meet water-demand needs while maintaining sound ecological environments throughout the basin.

In the future, the BRA will add two more sites for these types of surveys on the Little River.

Learn more about riparian vegetation here. Learn more about what a riparian zone is here.