Water Use Summary

​LCRA compiles water use information for the lower Colorado River basin in the annual Water Use Summary.

The dry conditions in place at the end of 2020 continued into 2021, with the basin seeing below-normal rainfall until the spring and summer. A wetter pattern began in late spring and continued through July, but the Highland Lakes saw limited runoff, as the rain fell intermittently and largely soaked into the soil. Dry conditions returned to the Highland Lakes watershed through the fall.

Total water use from the Highland Lakes and lower Colorado River decreased from 2020 to 2021. Water use from the Highland Lakes decreased by 43%, with reductions in all types of use. The increased runoff in the Colorado River downstream of the Highland Lakes in the late spring and early summer helped meet customer and environmental needs downstream. Diversions from the lower Colorado River increased by 18% from 2020 to 2021.

*Water use from the Colorado River was 358,185 acre-feet.

Water use by source – LCRA uses two basic sources of water to meet customer and environmental needs: water stored in lakes Buchanan and Travis and water naturally flowing in the Colorado River. When the natural flow into the Highland Lakes is greater than customer needs and environmental obligations, LCRA stores the excess in lakes Buchanan and Travis for later use.

Highland Lakes water use – Contracts for water stored in lakes Buchanan and Travis can be for firm or interruptible supply. LCRA also supplies water from the Highland Lakes to help maintain environmental flows, as required by the state-approved Water Management Plan. In 2021, the Highland Lakes supplied 211,841 acre-feet of water for all uses.

Firm water contracts – These contracts supply cities, businesses and industries that need a reliable long-term water supply. Firm supply is expected to be available through a repeat of the driest conditions the region has experienced. Firm customers accounted for 135,415 acre-feet, or about 64% of all water used from the Highland Lakes, in 2021. This includes 1,450 acre-feet used in hydroelectric generation to meet emergency needs for electricity, mostly in February during Winter Storm Uri.

Interruptible water contracts – These contracts supply agricultural customers. Interruptible water is subject to cutbacks during drought conditions. Interruptible customers used 45,109 acre-feet, or about 21% of all water used from the Highland Lakes, in 2021.

Environmental – FFrom time to time, LCRA releases water from the Highland Lakes to meet environmental flow requirements for the Colorado River downstream of Austin and for Matagorda Bay. In 2021, LCRA released 31,317 acre-feet, or about 15% of water released from the Highland Lakes, for environmental flows.