Castle, Maroon Creek reservoirs inappropriate and unnecessary |

Castle, Maroon Creek reservoirs inappropriate and unnecessary

Will Roush
Guest column

Tonight, the Aspen City Council will vote on whether to go to Colorado water court to prove they “can and will” build dams on Castle and Maroon creeks. Wilderness Workshop strongly urges council members to abandon the conditional water rights they hold to ensure the city never has the option to construct reservoirs on two of the State’s most iconic creeks.

At the City Council work session Sept. 27, all five council members described how important it was for Aspen to maintain the option of building dams in literally the last places anyone would rationally consider. All five council members referenced a need to keep these inappropriate reservoirs on the books in case they were needed in the future.

Given the council’s emphasis on the need to keep these reservoirs on the books for some future need, it’s worth looking at that claim a bit more. The city’s argument begins with two reasonable assumptions: population growth will increase the amount of water we use and climate change will make providing that water more challenging. Unfortunately, there was little connection made between these future impacts to our community and the need for reservoirs. There was no analysis of whether water storage would be the best way to meet these challenges or if so, whether these two reservoirs are in the best locations to do so. In fact, there was no discussion whatsoever of the reservoirs themselves.

What the city did reference was information from its 2016 Water Supply Availability Study that concluded, “The city can always provide sufficient potable and raw water supplies.” This study models projected water demand under different population growth scenarios for 50 years into the future and concludes that under the most aggressive growth projections of 1.8 percent, our indoor water use would increase from a maximum daily use of 3.4 cubic feet per second to 8.2 cfs. Outdoor water use in the summer peaks at almost double this, but I’ll give the City Council the benefit of the doubt and assume they wouldn’t justify flooding the Maroon Bells so we can water our lawns. The same report is much more vague on how climate change would impact streamflows on Castle and Maroon creeks, but the little information provided shows that under even the warmest and driest climate scenarios Castle and Maroon creeks would remain above 20 cfs each at their lowest flows (October-April). Clearly there would be plenty of water in the streams to turn on the tap in Aspen.

If it’s puzzling to you why the city would move forward with reservoirs when their own study shows no need, join the club. Perhaps though, as one or two council members suggested, these reservoirs are a failsafe to a doomsday climate scenario that their study didn’t contemplate. The problem with this reasoning is that this type of extreme future won’t affect just Aspen. If streamflows drop to such levels as would require damming these two creeks, it is almost assured that far more senior water-right holders across the West will prevent Aspen from using its relatively junior 1965 rights to fill the two reservoirs. If it’s bad here it’s going to be a lot worse in Las Vegas or Los Angeles, and the state of Colorado is legally bound to send water downstream.

If the city really thinks it needs to include storage as part of its water plan, it should do two things. First, conduct an analysis to determine if there is an actual need. And second, it should take a hard look at the feasibility of ever building dams on Castle and Maroon creeks. In my view, both reservoirs have fatal flaws, most notably a lack of social license to flood two spectacular valleys. But in particular, large portions of the Maroon Creek Reservoir would inundate the Maroon Bells-Snowmass Wilderness and require a never-before-granted approval by the president. The Castle Creek reservoir would require purchase of several multimillion-dollar properties and faces significant geologic problems. None of these issues were presented by city staff or discussed by the council.

It’s also worth setting the record straight on a false notion suggested by several council members on Sept. 27, namely that if Aspen gives up its rights, someone else could take that water. The Colorado Constitution guarantees that “the right to divert the unappropriated waters of any natural stream to beneficial uses shall never be denied.” At any time, anyone else could begin diverting water out of these two streams regardless of whether Aspen holds rights for reservoirs. Case law has shown over and over again that Aspen’s paper, conditional water rights provide no legal protections for these two streams. To stop someone from taking water out of the streams, the city would have to build the reservoirs.

The bottom line here is that Castle and Maroon creeks couldn’t be worse locations to build reservoirs. Aspen doesn’t need the water, and they have an opportunity to be environmental leaders by abandoning these rights to ensure these iconic and beloved valleys are not the site of industrial development.

Will Roush is the Conservation director of the Wilderness Workshop.