Critical Period/Drought Management

In times of declining groundwater levels, the EAA implements a Critical Period Management (CPM) Plan to help sustain aquifer and springflow levels. This program helps slow the rate of decline in aquifer levels and spring discharges during periods of little or no rain by reducing the amount of groundwater permit holders may withdraw.

Triggers, Stages and Reductions

Download Critical Period PDF

Reporting Requirements

During critical periods, all municipal, industrial and irrigation users are required to submit withdrawal reports monthly. These reports are reconciled at the end of the year to ensure permit holder compliance with the CPM reductions.

View Critical Period Management Tools

Jurisdictional Map

The EAA has regulatory jurisdiction in all of Bexar, Medina and Uvalde counties and portions of Atascosa, Caldwell, Comal, Guadalupe, and Hays counties.

EAA Notice for Intent to Finish Out a Crop

The Notice of Intent to Finish-out a Crop (NIFC) program has been recently revised. Please click the link below if you are an irrigator and need to learn about these changes. If you have any questions, don’t hesitate to contact us at 210-222-2204.

View Notice of Intent to Finish Out a Crop Video

What is CPM?

The EAA Critical Period Management (CPM) Plan helps sustain aquifer and springflow levels during times of drought by temporarily reducing the authorized withdrawal amounts of Edwards groundwater permit holders. By curbing pumping from the aquifer during periods of little or no rain, this program is designed to slow the rate of decline in aquifer levels and spring discharges until such time that it does rain and the aquifer can recharge itself.

Who does this apply to?

CPM stage reductions apply to all Edwards Aquifer well owners and groundwater permit holders authorized to pump more than three acre-feet annually. This applies to industrial, irrigation, and municipal users, including water utilities authorized to pump Edwards groundwater for delivery to their respective customers*.

In addition, all municipal, industrial and irrigation well owners are required to submit monthly withdrawal reports to the EAA for tracking of their pumping. These reports are reconciled at the end of the year to ensure permit holder compliance with the CPM reductions.

*It should be noted that the EAA does not enforce lawn watering activities or other general water limitations enacted. Any enforcement of such activities or limitations is enforced by a municipality. The EAA does not regulate the public, but instead regulates Edwards well owners with withdrawal permits authorizing their right to pump from the aquifer.

What are the stages of permit reductions and when are they declared?

The CPM Plan is divided into five stages of escalating reduced pumping requirements, each triggered by declining aquifer levels or springflow discharge rates as calculated in 10-day averages. In other words, required reductions increase as aquifer levels or springflows decrease. For example, Stage 1 of CPM is triggered and declared for the San Antonio Pool (all counties within EAA jurisdiction except Uvalde) when the 10-day average level at the J-17 Index Well, in Bexar County, drops below 660 feet above mean sea level (amsl) or the 10-day average spring flow at Comal or San Marcos Springs falls below 225 cubic feet per second (cfs) or 96 cfs, respectively. As a result, permit holders must reduce groundwater withdrawals by 20% of their authorized annual withdrawal amounts based on the number of days CPM is in effect.

See the graphic below for a detailed explanation of permit reductions for each stage of CPM.

Download Critical Period PDF

Reach out to your water provider to determine if stage restrictions have been declared.