In certain Colorado circles — call them Water Buffs as opposed to Water Buffaloes — Republican gubernatorial candidate Dan Maes has been criticized for sounding ignorant when he addressed the Colorado Water Congress in Vail last week.

“If it starts in Colorado, it’s our water,” he said. “The question is how do we keep it here. We need to store as much of our water in Colorado as possible.”

In theory, his policy certainly would solve Colorado’s water supply problems. Our state covers about 66.6 million acres. Informed estimates of our average annual statewide precipitation run from 16 to 18 inches. Going with the conservative 16 gives us 88.8 million acre-feet.

If an acre-foot a year is enough for the typical suburban household with a lush lawn and four inhabitants, then enough water falls on Colorado for 355 million people — more than the current population of the U.S.

So where does all this water go if we’re not using it? If Tom Tancredo, candidate from the Constitution Party, had addressed the issue, he might have mentioned that some of our water flows to Mexico via the Rio Grande and the Colorado, and he could stop that by sealing the border.

But let us return to reality. Thanks to prodding from the U.S. Supreme Court, which hears cases between states, Colorado has negotiated agreements to deliver water to downstream states. The most famous is the seven-state Colorado River Compact of 1922, but Colorado is party to many other river compacts: South Platte, Arkansas, Rio Grande, Republican, Laramie, La Plata, North Platte, even Costilla Creek.

While that may annoy Maes, it seems only fair. Water flowed downstream long before there was a Colorado. If your farm water came from an 1850 acequia along the Rio Grande in New Mexico, why should you lose your irrigation because some new state was created to the north in 1876 and its governor later decided that since the water started above the state line, he could keep it there?

If Maes tried “keep it here” because “it’s our water,” we’d see years of expensive litigation as we contended with Kansas, Wyoming, New Mexico, Nebraska, Utah, Arizona and California. As for the mechanics of keeping it, Maes wants to build more reservoirs, which would be expensive. Coloradans are generally rather adverse to tax increases or water-rate increases, so it’s a mystery where the money would come from. Perhaps the private sector will step in, but what if a private firm decided it could make more by selling the water to Arizona or California?

The simple fact is that most Colorado precipitation doesn’t reach our rivers so it can be stored in reservoirs or delivered to downstream states. It doesn’t disappear beneath the surface, either. What doesn’t evaporate directly is taken up by plants. Some by farmers’ crops, but mostly by buffalo grass, tamarisk and cottonwoods, by mountain meadows, aspen and ponderosa.

In the early 1970s, Shelton Farms in the Arkansas valley cut down some useless water-sucking cottonwoods, then claimed a right to the water that had formerly been wasted on the phreatophytes. The Colorado Supreme Court held that our law does not allow such water rights; instead, the “salvaged” water belongs to the entire river system, not the tree-cutter. However, the court noted that the legislature could change the law.

So there’s an approach for Maes. He could campaign for the change, so as to increase Colorado’s water supply by decreasing the number of trees — which seems to be happening anyway, thanks to pine beetles.

But he didn’t propose this logical and legal way to increase our water supply. Does that mean he’s ignorant about our laws and obligations? Not really. Since he says “it’s our water” and we should keep it here, it appears that he understands the saying, “I’d rather be upstream with a shovel than downstream with a water right.”

Ed Quillen (ekquillen@gmail.com) of Salida is a regular contributor to The Denver Post.