The following video is from the University of Wyoming Cooperative Extension Service and gives a basic overview of the prior appropriation of water rights to the State’s rivers and streams.  A transcript follows the embedded video.  The short of it is that when it comes to appropriative rights, it’s first in time, first in right.

TRANSCRIPT:

You hear that?  It’s water being sucked through a headgate.

Now across most of Wyoming, more water will evaporate during a year then will fall as rain or snow.  That’s why we irrigate.

Mark Twain said, “Whiskey’s for drinkin’, and water is for fighting.  “It’s because water vastly increases land productivity, value and ability to sustain Wyoming’s agriculture.

Wyoming water is owned by the State and rights to use the water are issued by the State through the Wyoming State Engineer’s office, though there are other permitted uses. Irrigation is by far the greatest use of Wyoming water.

Like most western states, the oldest rights get first dibs on stream flow. The oldest water rights on a stream are allotted two cubic feet per second per seven acres of land. Now that figures out to be about 15 gallons a second for a 70-acre piece.  In more familiar terms, it’s about like sprinkling an inch and four tenths of water on your lawn every other day.

Now, when stream flow isn’t abundant, younger water rights are shut off in favor of older water rights. That’s a mighty frustrating prospect for a junior water right and it’s the source of Mark Twain’s observation.

From the University of Wyoming Cooperative Extension Service, I’m Eric Peterson.