The San Juan #Water Conservancy District sees draft of #SanJuanRiver water supply and demand analysis — The #PagosaSprings Sun

Pagosa Springs Panorama. Photo credit: Gmhatfield via Wikimedia Commons

Click the link to read the article on the Pagosa Springs Sun website (Dorothy Elder). Here’s an excerpt:

The San Juan Water Conservancy District (SJWCD) Board of Directors saw the first draft of an Upper San Juan River Basin water supply and demand analysis at its July 25 meeting.

The analysis, conducted by Lakewood-based consultant Wilson Water Group (WWG), studied the supply and demand through 2050 in the Upper San Juan River Basin and was commissioned by the SJWCD. Presenting the results, Erin Wilson, principal at WWG, noted that the results are still a draft and that its findings could be revised or expanded depending on feedback from the board.

The goals of the analysis were to document “current and potential future demands for water from municipal, agricultural, and environmental and recreational users” in the region, as well as “identify options for meeting any potential shortages in water supply in the future,” Wilson stated. The “unprecedented growth” of the Town of Pagosa Springs and ongoing drought conditions of the San Juan region emphasize the importance of this study, Wilson explained…

These demands showed an average annual future shortage that ranges from around 4,100 acre-feet to 73,000 acre-feet in the analysis. Wilson clarified that the shortages incorporate the area’s current water storage capabilities. From these numbers, the analysis suggests potential Dry Gulch reservoir sizes that could meet the needs of the demand projections. The limiting factors in reservoir sizing are the legally and physically available water to fill the reservoir, the 50 cubic feet per second (cfs) filling constraint, and the demands driving reservoir releases, the analysis explains. The 50 cfs limit is based on the Dry Gulch Reservoir water right, and the Dry Gulch environmental flow stipulations have to be met when the reservoir is filling, Wilson explained.

“Note that because the annual high demand shortages are greater than water available for filling (limited by 50 cfs), the reservoir inflow cannot keep up with the reservoir releases; therefore, a reservoir cannot meet the high demand shortages regardless of size,” the report reads.

The recommendations for the reservoir size are 1,600 acre-feet to meet low demand and 10,000 acre- feet to meet mid-range demand. Wilson clarified these calculations are usable volume numbers, not the total volume of the reservoir. The report also offers alternatives to the construction of a reservoir that could potentially lessen shortages and meet demand projections. These include stream restoration, agricultural fallowing and improved forest health…Many of these potential solutions are experimental at this point, and the report suggests that SJWCD “continue to monitor on-going projects to see how the results could be applicable in the Upper San Juan basin.”

Overall, board members brought forward many suggestions to strengthen the report. This included a deeper analysis of wildfire resiliency, leaking issues with PAWSD and a more in-depth look at the need for a reservoir.

There was also a dispute over the 226 gallons per capita per day metric, which board member Joe Tedder thought sounded too high based on Colorado averages.
Wilson clarified the number is the region’s entire demand — commercial included — and not just household use.

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