Conditions
2025 Critical Period Calculator
This auto-fill calculator allows you to accurately determine your authorized groundwater withdrawal amount for the current total number of days that a stage of Critical Period Management (CPM) has been in effect in the San Antonio and Uvalde Pools. To use, simply select the pool for your area along with the corresponding year of critical period and the program will automatically display the stage(s), number of days, and applicable reduction rates. To calculate your accurate reduction, enter your annual authorized groundwater withdrawal amount in the appropriate box and click the Calculate button. Your new authorized amount is displayed in red. Reset the calculator each time to repeat the process as necessary.
If you wish to forecast your possible end-of-year reduction please use the Critical Period Forecast Calculator or the Interactive Critical Period Calculator if you are an irrigation user who has filed a Notice of Intent to Finish Out a Crop form.
| Stage | % | Days in Stage | Start | End | Reduction |
|---|---|---|---|---|---|
| Stage 4 | 40% | 109 | 01/01/2025 | 04/19/2025 | 11.95% |
| 109 | 11.95% | ||||
| Stage | % | Days in Stage | Start | End | Reduction |
|---|---|---|---|---|---|
| Stage 5 | 44% | 109 | 01/01/2025 | 04/19/2025 | 13.14% |
| 109 | 13.14% | ||||
The above Critical Period calculator is made available to you by the Edwards Aquifer Authority (“EAA”). It is provided to you as a tool to monitor and manage your water use. The EAA makes no claims as to the accuracy or completeness of the results, for any particular purpose, produced by the calculator. If you use the results for any purpose, the responsibility of that use is entirely with you, the user. By using the calculator, you are accepting all the terms of the disclaimer notice.
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