A letter to City Manager Peter Zanoni says the city wants to pause some freshwater releases from reservoirs while lake levels remain critically low.

CORPUS CHRISTI, Texas — Corpus Christi Water (CCW) is asking state regulators to temporarily modify environmental water release requirements as the region continues to face historic drought conditions.

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In a memo dated May 28, CCW Chief Operating Officer Nicholas Winkleman told City Manager Peter Zanoni that the city has hired consulting firm HDR, Inc. to help review possible changes to the Texas Commission on Environmental Quality, or TCEQ, Agreed Order tied to the Wesley Seale Dam.

The agreement controls how much freshwater must flow through the reservoir system into the Nueces Estuary to help protect downstream habitats when water is available.

According to the memo, the city manager directed CCW staff to work with HDR, TCEQ, the Nueces River Authority, and the City of Three Rivers to request a temporary modification to the agreement due to ongoing drought conditions.

Under current rules, no environmental releases are required when reservoir levels fall below 30%. But city officials are asking TCEQ for flexibility so those release requirements would remain paused until reservoir levels recover to 50%.

The memo states the temporary adjustment would stay in place while officials consider whether a long-term change to the agreement is needed.

The agreement was first established through the city’s surface water permits and requires scheduled freshwater inflows each month into the Nueces Estuary. 

Officials say the purpose is to help mimic the natural flow of the Nueces River and maintain the health of the estuary system.

The agreement has been in place in some form since the early 1990s and was last amended in 2001.

The memo also notes that no changes to the agreement can be made without unanimous approval from the certificate holders, unless permitted by law.

As of May 28, the combined capacity of Choke Canyon and Lake Corpus Christi was listed at 10.3%.

At that level, the city is not currently required to make environmental pass-through releases under the existing agreement.

According to the memo, annual pass-thru requirements are based on reservoir levels:

Above 70% capacity: 138,000 acre-feetBetween 40% and 70%: 97,000 acre-feetBetween 30% and 40%: 14,400 acre-feetBelow 30%: No pass-thru required