Q. Does Denver Water sell water to other states, such as California?
Denver Water does not sell water outside the state of Colorado. No one else sells water to California either, because it is not permissible to sell Colorado’s water outside the state.
The water that flows from the Colorado River to California was allocated under the 1922 Colorado River Compact, which is an agreement among the upper basin and lower basin states about how to allocate water in the Colorado River. Each state was allocated a portion of the river’s flow, and those states that did not take all the water they were entitled to had their rights preserved forever. (Normally, under western water law, if one doesn’t use the water to which he/she has rights, those rights can be taken away.)
Because Colorado didn’t have enough demand in 1922, it did not (and still does not) take its entire share of water to which it was entitled. California, however, has taken more than its share for many years. Recently, the U.S. Department of the Interior moved to stop California from taking more than its share. That water is being held in a reservoir on the lower Colorado River now. The compact was affirmed by Congress and is a part of federal law now. It can only be terminated by an act of Congress and with the unanimous consent of the compact states.
Q. Why can't Denver Water customers reuse their own graywater for outdoor use?
Colorado water law allows each customer just one use of water before it goes down the drain, through a wastewater treatment plant and back into the river for others to use. By law, Denver Water customers are not allowed to use bath or laundry water (commonly referred to as graywater) for other purposes. After this water is used once by Denver Water customers, it must return to the South Platte River where it will be used seven or eight times before it gets to Nebraska. Denver Water does not endorse graywater systems.
Q. Can I collect rainwater?
Capturing rainwater is an ongoing issue in Colorado, and it is not allowed if it will injure vested water rights. For the most part, Colorado law does not allow Denver Water customers to collect rainwater.
In 2009, however, the Colorado State Legislature passed two laws that carve out exemptions from the general rule.
The first law says that if you are not served by a domestic water system, such as Denver Water, and you are located in a designated ground water basin or your collection system qualifies as exempt from 37-92-602(1)(g)(I), you are allowed to capture rainwater for household, fire protection, stock watering and irrigation of up to one acre of lawns and gardens as long as it is applied to uses specified in the well permit that applies to your property.
The second law allows the state to participate in a study of 10 new developments to determine the impact of capturing rainwater on streams, rivers and tributary groundwater.