John Erwin
Director, Natural Resources Planning & Management
Last week TMWA informed the local media that we will ask customers to reduce outdoor watering by ten percent beginning in late July. Additionally, we will increase no-watering times by two hours—from 11:00 a.m. to 7:00 p.m. This is the hottest part of the day, when most evaporation occurs.
Since this information was released, we have received numerous calls and emails from our customers asking why we are not implementing these conservation measures immediately. The idea being that the earlier we begin saving, the more water we’ll have in our reserves later on.
The not-so-simple answer is: because of the way the Truckee River is operated. Water releases from Lake Tahoe and Boca Reservoir are required to meet minimum river flows at the CA/NV state line. These releases are administered by the Federal Water Master under court decrees from the 1940s. The current water supply forecast shows that upstream reservoir storage will be sufficient to provide releases for these required rates of river flow through about the end of July. When the water levels in Lake Tahoe and Boca Reservoir are no longer sufficient to release water for minimum flows, Truckee River flows will begin to drop off. At that time, TMWA plans to make releases from our drought storage reservoirs (Donner and Independence Lakes) to supply water to our treatment plants. That is the time when our customers can make a difference by conserving water, which will minimize the amount we need to release from our drought reserves.
Another important factor is that we are ready and we have been planning for just such an occasion. TMWA’s drought supply reservoirs – Donner and Independence Lakes – are full. Until we have room in our reservoirs, TMWA has no place to store additional conserved water. We are not planning to begin using our drought reserves until as late in the summer as possible and will ask our customers for their help in conserving when it counts—which will be when we start using those reserves. TMWA will continue its three-day- a-week watering schedules throughout the summer and encourages everyone to use water responsibly. Our customers have always been diligent about conservation and are encouraged to keep up the good work.