By Alan Prendergast
By Michael Roberts
By Michael Roberts
By Amber Taufen
By Patricia Calhoun
By William Breathes
By Michael Roberts
By Melanie Asmar
By the 1960s, it was evident that the era of reservoir and dam building was nearing an end when the Army Corps of Engineers would not recommend construction of a massive reservoir on the South Platte at a place east of Brush called The Narrows. In 1964, concerned farmers banded together into the Lower South Platte Conservancy District to push for the project, which would have been the third-largest reservoir in the state next to the CBT's Lake Granby. But the reservoir plan was defeated by a vote of the taxpayers.
Despite the moratorium on reservoirs and increasing demands, the South Platte seemed to be growing. As far back as the turn of the century, the state engineer, as well as hydrologists at what was then Colorado A&M (and now Colorado State University) had noted that the South Platte was flowing longer than it had in the past. In fact, the river could be drained dry at one ditch's headgate and yet have water in it again a few miles downstream. Under "one-time use" Colorado water law, farmers do not have the right to recapture and reuse water that isn't consumed by crops after they've irrigated a field. They're required to return the unused portion, usually by ditches created for that purpose, back to the main ditch or river so that it can be used by the next farmer downstream.
These return ditches alone, however, couldn't account for all the water flowing in the river. The experts finally realized that some of the water had to be seeping from the ditches or soaking into the ground, then making its way to the river. And if that was the case, the water still belonged to whomever had a senior right.
Even with the added flow, the reservoirs couldn't meet the needs of all the water users on the South Platte. So the '50s marked the start of extensive reliance on irrigation wells. These were not small, household wells, but wells capable of pumping thousands of acre-feet from below the surface in a day. At first, no one gave much thought to where all that well water was coming from or the effect it might have on the river itself -- but that time was coming.
Water law was becoming more complex, and keeping up with who owned what priority right was increasingly difficult. River drainages obviously cross county lines, and decisions weren't always communicated from one district court to the next. So in its 1969 act, the legislature decided to divide the state up into seven divisions -- one for each of the major river drainages, and each with its own centralized, and specialized, water court with a single judge. The South Platte was the focus of Division One, with its court in Greeley.
But the act did more than create the divisions and courts. The legislature also established a "division engineer" position to oversee and police Colorado water law in each division, as well as consult with and make recommendations to the water court judges; the division engineer would report to the state engineer. The water commissioners, each responsible for a piece of the drainage -- such as Boulder Creek or the St. Vrain River or a stretch of the South Platte -- now worked for the division engineers.
The act attempted to bring well owners into compliance with the rest of the state's water users, too. Farmers with senior water rights had looked at their dry ditches and thirsty crops, and then at their neighbors upstream, who had junior rights on the river but were pumping thousands of gallons of water onto their fields, and complained: That had to be their water going to the underground flow. Few issues in Colorado carry the weight of water, and the lawmakers listened.
Well users were now required to register their wells and fall in line under the "first in time, first in use" doctrine - putting them at the back of the line. They would have to find a means to augment, or replace, the water they used and put it back in the river, or they would have to stop pumping.
Replacing water isn't as easy as simply buying some from an owner upstream and shipping it down the river to the injured party. The replacement water would never make it unless it was shepherded by the water commissioners past senior water rights holders, which the act authorized them to do.
This replacement process could cost more than it was worth. For every mile of river it travels, about 1 percent of the water is lost to seepage and evaporation. So about half of the 100 acre-feet of water released fifty miles upstream would be lost before the rest reached its destination. Well users preferred to find a source of replacement water near the point of impact on the river.
One of the first hurdles was determining how quickly underground water flowed to the river. Water pumped by a well a number of miles from the river might have taken years to reach the river; thus the "injury" and need to rectify it wouldn't occur until that point. This rate could vary depending on such factors as type of soil underground or steepness of the ground. So studies were conducted to map Stream Depletion Factors, or SDF, so that division engineers could calculate when water from a certain area could have been expected to reach the river.