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Trinity Aquifer Hydrology

Middle Trinity Aquifer

Texas Map of the Middle Trinity Aquifer

The Trinity Aquifer region consists of early Cretaceous age rocks that range in a band from the Red River in North Texas to the Hill Country of south-central Texxas and provides water in all or parts of 55 counties. The Hill Country region of the Trinity Aquifer provides water for nine counties. These counties form the Hill Country Groundwater Conservation Districts Alliance (HCA). The HCA is a newly formed organization that funds the research of 40 groundwater-monitoring stations that examine the aquifer leveling various points throughout the HCA region.