From The Greeley Tribune (Eric Brown) via The Fence Post:
Roundtable members, made up of water experts and officials in northeastern Colorado, stressed during their meeting that — because it takes water-supply projects, such as new reservoirs, 20-30 years to come to fruition, from the planning stages to their completion — the expected shortfalls in the South Platte’s water availability could arrive before enough new projects can come to fruition. That is, unless much more aggressive planning among regional and state water officials begins to take place soon, members agreed…
South Platte Roundtable members also made note of the ongoing push from others in the state — particularly those from the Western Slope — to heavily rely on conservation efforts to meeting future water needs, rather than depend on building new projects that transport water from the Western Slope to the Front Range. Roundtable members pointed out that conservation is complicated in the South Platte, because so many of its users depend on reused water. They noted that many other people in the state don’t fully understand that, and more education is needed.
Unlike other basins in the state, water in the South Platte Basin is reused six or seven times before it flows out of the state. South Platte water users, particularly those east of Greeley and further downstream, are dependant on water that’s used in the Denver area and other parts of the upper South Platte region, treated before it returns to the river and then flows downstream to be used again. It’s estimated that about 50 percent of the water used by farmers in flood irrigating returns to the river — either by soaking through the soil and into underground aquifers, or through ditch runoff. About 18 percent of water used in residential lawn irrigating is estimated to return to the river.
With its reuse system in place, the South Platte Basin’s economic value per acre-foot of water is higher than any other basin in the state.
More South Platte River basin coverage here.