Here’s a look at the plan to bank water rights in priority before the Colorado River Compact, from Bob Berwyn writing for the Summit Daily News. From the article:
The Colorado River Water Conservation District and the Southwest District met in Durango last week to discuss details of the plan, which would put senior water rights into a bank where they could be tapped in case of such a compact call.
Water users with pre-1922 rights (those senior rights are not affected by a downstream call) would be compensated for offering their senior water rights to junior users for temporary critical uses like drinking water and firefighting. The temporary use would only be permitted if a compact call were in effect or imminent.
Under the 1922 interstate contract, Colorado is obligated to deliver an average of 7.5 million acre feet of Colorado River water downstream annually. In a worst-case scenario, Colorado water users could be forced to cut some of their existing uses if the downstream states demand their full allotment. Water rights established before the compact was signed are not subject to the agreement.
Most of the water rights available for such a bank are held by ranchers and farmers.