You may have heard some discussion about the phrase Use It or Lose It lately. First, about how it is a guiding principle when using water under Colorado’s prior appropriation system. Then, more recently, about how it can be a misleading cliché.

It’s true that in certain straightforward situations, failure to use a water right for its decreed use will result in the loss of some or all of the water right. However, from there, it gets more complicated.

In 2015, a group of Colorado water professionals representing interests from around the state collaborated to explore Use It or Lose It’s application to water use. The discussion was initiated by the Colorado Water Institute. The Water Institute approached the concept by first identifying five areas where water users have concerns about losing their water rights.

The first three areas of concern are Maintaining a Conditional Water Right, the Continued Use of an Absolute Water Right and Abandonment of a Water Right. In Colorado a water user may obtain a conditional water right based on a non-speculative plan to use the water. If that person does not apply the water to its decreed use within a period of time, or at least maintain a diligent effort to develop the water right, it may be terminated by the water court. The water right is lost due to lack of use.

When the owner of a water right considers the risk of abandonment of some portion of a water right or the possibility of changing a water right to a different beneficial use (the fourth area of concern), the owner of the water right may consider it advantageous to divert as much water as possible — more than is needed for the applied use. The unintended consequences of doing that can range from unnecessarily taking water that could be used by water rights immediately downstream, to impacting sensitive fish and wildlife habitat, to increasing the water right owner’s own return flow obligation if the use is changed. Further, the water court doesn’t consider water diverted but not consumed as water that may be applied to a new use. So the practice of diverting more water than is needed, which is called “waste” in water administration, can actually be detrimental.

A fifth area of concern is the effect that Conservation and Sustainability Efforts can have on the value of a water right. To understand more about that area of concern and the rest of this issue, read Special Report No. 25: “Is ‘Use It or Lose It’ an absolute?” available on the Colorado Water Institute home page.

Kevin G. Rein is the deputy state engineer for Colorado Division of Water Resources.Kevin G. Rein is the deputy state engineer for Colorado Division of Water Resources.Kevin G. Rein is the deputy state engineer for Colorado Division of Water Resources.