Payson has reached 99 percent of safe yield, according to the 2003 Water Status Report released by the town Friday.
The report also shows that significant recharge of town wells did not occur during the past water year -- April of 2002 through March of 2003, that consumption was up nine percent during 2002, and that the drought that has gripped the Rim country for several years continues. As a result, Water Conservation Level 2 measures will be imposed on town water customers beginning May 1 under terms of the new water conservation ordinance passed by the town council earlier this year.
Town hydrologist Mike Ploughe explained the formula mandated by the new ordinance, which took effect March 1:
"We look at last year's consumption and last year's overall usage and then we project out the production rates for the wells for this coming summer based on their lows for the last summer, and we can see if we're going to meet peak demands," Ploughe said. "And we will -- we're going to be OK this year again -- but the annual precipitation was far enough below normal to keep us at Level 2 for the next full water year."
According to the report, a total of 18.07 inches of precipitation fell during the 2002-03 water year, 17 percent below the average annual precipitation of about 22 inches. Ploughe said he is not optimistic that the town's water situation will improve anytime soon.
"I'm just not very excited about the long-term precipitation," he said. "I hope it changes, but there's a 60-year cycle and it takes 30 years to get to the bottom of it; we've got another 12 (years to go) before we're in the bottom."
"It was above normal only because of one-and-a-half to two weeks of heavy precipitation in February, but that doesn't do it," Ploughe said. "What we need is average or above average (precipitation) every month. It doesn't do the aquifer (much) good when you get it all at once, because it just can't soak it all up."
Ploughe blames at least part of the increase in consumption on the lingering drought.
"Water demand increased quite a bit last year because of the drought," he said. "Normally -- on average -- we'd expect the increase from one year to the next to be about 3 or 4 percent. We've got 9 percent growth, and that's just an average."
The report shows that monthly consumption ranged from a 26 percent increase in April over 2001 to a 23 percent decrease in November due to a record high demand during that month in 2001. The only other month that experienced a consumption decrease in 2002 was September (-0.4 percent), thanks to above normal precipitation.
The drought and increased consumption combined to push the town to the brink of exceeding safe yield for the first time.
Safe Yield is the point where the amount of groundwater consumed is at or below the amount naturally or artificially replenished. When the consumption exceeds 100 percent of safe yield, the town will be using more groundwater than is being replenished.
"In Payson, this value has been estimated to be 1,826 acre-feet per year. This means that so long as no more than 1,826 acre-feet of groundwater is consumed, the town of Payson is within its safe yield ... Unless conservation measures are practiced, safe yield will more than likely be exceeded in 2003."
A table in the report shows that the percentage of safe yield has steadily increased from 55 percent in 1990. Ploughe said reaching safe yield is the most significant finding in the report.
"The big one is safe yield," he said. "We're at 99 percent of safe yield as of the end of last year, and to date the town council has been taking the line that we do not want to go over safe yield, so certain things are going to have to be done to make sure that doesn't happen this year."
The restrictions automatically imposed by the new water conservation ordinance are a necessary part of a drought management plan, according to the report.
"A key component of the ordinance is the possible institution of water use restrictions each spring in order to achieve reduced water consumption commensurate with the amount of local precipitation that occurred in the previous year," the report says.
The Level 2 restrictions that will be automatically imposed as a result include a ban on washing paved areas such as sidewalks and driveways and limiting outside water use to odd or even days of the week depending on street address."
Other efforts include an increase in conservation education and an increase in water rates that will take effect in May.
The new rate structure is aimed at high water users and reflects an increase in every use category except 2,000 gallons or less per month.
The town council added a $1 per month surcharge to the base rate and directed that the extra revenue be used on conservation programs.
Ploughe hopes it will be enough.
"I wouldn't say it's ‘grim,'" he said. "But I would say it's pretty clear that we're still in a drought cycle that could last a number of years. We need to be conservative in our water use."