Now that the Star Valley Watershed Safe Yield study has been released, Mayor Bob Edwards said he hopes Payson can now sit down with Star Valley to discuss what the report really means.
Edwards said he thinks it "obviously" means two things.
He said the report, to him, shows there is a sizable amount of water in Star Valley's watershed and the Tower Well is not threatening their watershed.
The Star Valley Watershed Safe Yield study revealed that it is theoretically possible to capture 4,300 acre-feet of groundwater outflow from the Star Valley area without causing long-term declines in regional water levels.
However, according the executive summary that was released this week, it would not be realistic to capture the entire outflow from the basin without local effects that could be detrimental or result in localized water level declines.
Southwest Groundwater Consultants, in a 1998 study, concluded that 80 percent of the safe yield was a more appropriate value for use in water management decisions for the Town of Payson, to allow for uncertainty in the estimates.
In July 2006, the town council agreed to hire Clear Creek Associates to conduct a similar study.
Using this approach, according to the summary, a practical safe-yield study value for the study area would be 3,440 acre-feet per year or 80 percent of the 4,300 acre-feet safe yield estimate.
The study that the Town of Payson paid $50,000 for revealed:
- Approximately 4,300 acre-feet is available in the watershed based on the average precipitation of 21.53 inches a year.
- Safe yield is an average value reflecting long-term precipitation rates from 50 to 100 years.
- The approximate population of Star Valley is 2,500 residents. Using 100 gallons per person per day as an estimate of water use, the annual groundwater demand would be 280 acre-feet.
- Taking into account the pumpage from the Mayfield Canyon Well of approximately 100-acre feet per year, the total demand would be 380-acre feet per year.
- There would be, in addition, some use from the Payson wells in Chaparral Pines.
Payson Town Manager Fred Carpenter said the town council next Thursday will vote on whether to accept the report.
He also said if the report is approved, it would be used for the future in water resources planning.
Star Valley Town Manager Vito Tedeschi said LFR Environmental Management & Consulting Engineering will review the report and inform its council what it means.
Star Valley Mayor Chuck Heron said he had just received the report and was going to refrain from comment until the rest of the council could see it.