(Note: The Twin Buttes north pool is currently above the 1926.5' elevation, at which point the north and south pools are considered equalized as a single body of water. The conservation acre-feet storage capacity, used in determining the full capacity of the reservoir, is taken from the revised March 2018 tables developed by the United States Department of the Interior, Bureau of Reclamation, Great Plains Region (using 1964 tables plus 1970 USGS Survey data) for the Middle Pool, with an additional 4,602 acre-feet added to account for the additional water in the south pool.)
San Angelo is in Standard Conservation, which restricts outside watering to once every seven days at no more than 1 inch per week, no watering between noon and 6 pm. Hand watering of lawns, gardens, landscape areas, trees, shrubs or other plants being grown outdoors or foundations may be done on any day, except during the prohibited watering hours of noon to 6 p.m., provided the allowable application rate of 1 inch per week is not exceeded. Landscape or foundation watering with a drip irrigation system such as a soaker hose, deep root watering system, drip pipe or tape, or bubbler shall be permitted on any day and at any time of day provided that the total amount of water applied shall not exceed 1 inch per week. Golf course greens may be watered daily except during the prohibited watering hours of noon to 6 p.m. Runoff of more than 150 feet down any street, gutter, alley or ditch is prohibited.