Frequently Asked Questions About Western Water Law

Q. Does Denver Water sell water to other states, such as California?

A. Denver Water does not sell water anywhere outside the State of Colorado. No one else sells water to California either since 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 Colorado River Compact over 80 years ago. It is a compact among the upper basin and lower basin states that receive waters from the Colorado River. Each state was allocated a portion of the river’s flow and those states that did not take all the water that they were entitled to had their rights to their share preserved forever. (Normally, under western water law, if one doesn’t use the water to which he/she has rights, those rights can be permanently forfeited.)

Since Colorado didn’t have enough demand in 1922, it did not take its entire share of the water to which it was entitled and still doesn’t. California, however, has taken more than its share for many years. Recently, the Department of the Interior moved to stop California from taking more than its share because the state did not come up with a voluntary plan. (That water is being held in a reservoir on the lower Colorado as of 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 gray water for outdoor use?

A. Colorado water law allows each customer just one use of the 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 permitted to take their bath or laundry water (commonly referred to as gray water) and dump it on their outdoor plants or garden. 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 more times before it gets to the state line (Nebraska). State water laws are enforced by the State Engineer's office (PDF). Denver Water does not endorse any gray water systems.

However, Denver Water customers are encouraged to catch unused clear water in a bucket or other container as it comes out of the tap and then use this water once; to mop floors, refresh pet water or water plants. For example, try catching water that comes out before the shower water warms up and then use this water to flush toilets or rinse the shower.

Q. Why doesn't Denver Water have rebates for rain barrels so we could catch our rain and put it on our plants?

A. Colorado Water Law requires that precipitation fall to the ground, run off and into the river of the watershed where it fell. Because rights to water are legally allocated in this state, an individual may not capture and use water to which he/she does not have a right. We must remember also that rain barrels don't help much in a drought because a drought by its very nature supplies little in the way of snow or rain. The reuse of household water (gray water) is regulated by the Colorado State Board of Health Guidelines On Individual Sewage Disposal Systems (PDF). Local health agencies are responsible for implementation and enforcement of the Guidelines.

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