The Blue Ridge Reservoir has dwindled to just 28 percent of its capacity in the wake of one of the driest years ever recorded on the watersheds of the Salt and Verde rivers.
The reservoir on which Payson’s water future depends never got much above 60 percent full, thanks to a dry winter and near-rainless spring.
The alarming drop in the Blue Ridge water levels in the face of one of the most severe droughts on record worries some people about the long-term reliability of the Blue Ridge Reservoir and has sent ripples through the increasingly contentious Payson mayor and town council race. The Blue Ridge Reservoir actually drains north, into the Little Colorado River, but watershed sustaining the reservoir has also suffered a dry year. However, the 77-square-mile watershed remains one of the most productive in the state and the reservoir could refill in a single wet year, said Jeffrey Lane, an SRP spokesman.
This year the crucial watershed draining into the Salt River Project reservoirs generated about one-third of its normal runoff, the fourth dry year in a row.
Salt River Project delayed the normal start of releases from Blue Ridge into the East Verde River and now has significantly drained the 15,000 acre-foot lake. SRP will continue releasing water until levels fall below the 2,100 acre-foot minimum called for in SRP’s agreement with the federal government.
Lane said the reservoir could hit the 2,100-foot mark in early August, which would mean SRP would then shut down the extra flow of water into the East Verde.
SRP noted that last winter’s snowmelt season on the Salt and Verde river systems produced just 148,000 acre-feet, the eighth-driest year since the start of record-keeping 116 years ago. The watershed got less than 3 inches of precipitation from December 2013 to March 2013 — about 37 percent of normal.
That vast watershed protected by the Tonto National Forest normally produces 534,000 acre-feet, according to the running, 30-year median. The water runs into a chain of reservoirs on the Salt and Verde rivers, with Roosevelt Lake holding about two-thirds of the total supply.
Roosevelt has fallen to about 42 percent of its capacity. However, the total system still holds 52 percent of its capacity, despite a series of poor water years.
Fortunately, the development of warm, eastern Pacific surface water pattern known as El Niño promises a perhaps wetter-than normal monsoon and winter season. One good winter could refill Roosevelt and Blue Ridge.
The region enjoyed a wet winter in 2010, with runoff of 1.4 million acre-feet — nearly three times the normal. The system of reservoirs can store 1.2 million acre-feet and SRP delivers at least 1 million acre-feet of water annually to the Valley. That wet winter filled all the reservoirs to capacity in May of 2010.
However, rainfall has remained well below normal ever since, gradually draining the reservoirs.
SRP Manager of Water Resource Operations Charlie Ester said, “In spite of the consecutive dry winters, our reservoir system is in a good position to provide full allocation to our water customers because of SRP water resource management practices. We’re keeping our fingers crossed for an active 2015 runoff season, and so far the early indications are good.”
Blue Ridge started 40 feet below full pool even before SRP started pumping the extra water released into the East Verde. SRP pumps the water out of the reservoir, then it runs downhill all the way to Washington Park, generating enough electricity as it runs downhill to run the pumps. At Washington Park, the water gushes out of a huge pipe and into the East Verde.
Payson spent 20 years winning legal right to 3,000 acre-feet of Blue Ridge water annually, more than doubling its long-term supply. Town officials say the Blue Ridge water will provide all the water the town needs even if it grows to the 38,000 population possible with build-out to maximum densities under the current general plan. However, skeptics say that a projected increase in drought in coming decades may reduce the yield of the reservoir.
Payson’s agreement with SRP gives it rights to a rolling average of 3,000 acre-feet annually. That means in some years it may not get its full 3,000 acre-feet due to drought, but could draw more than 3,000 acre-feet when the reservoir refills.
Payson pays 27 percent of the cost of running and maintaining the existing system under the terms of its agreement with SRP, even though it isn’t yet getting any water. Payson’s 3,000 acre-feet is currently flowing into the Verde River and down to SRP’s Horseshoe Reservoir for use in the Valley.
Payson Mayor Kenny Evans noted that SRP indicated it would nearly empty the reservoir this year in order to work on the pumps and intake tunnel normally deep beneath the surface by the dam. SRP needs to make improvements on the system for getting water from the reservoir to Washington Park at the headwaters of the East Verde, since once Payson hooks up to the system it will be providing drinking water.
Payson originally intended to pay for the roughly $50 million Blue Ridge project mostly with a $7,500-per-house water impact fee on new construction. However, the collapse of construction during the recession dried up impact fees. The town raised its water rates and has since sought ways to boost water sales to provide the revenue stream needed to qualify for some $28 million in long-term, low-cost state or federal financing to finish the pipeline.
However, things like a repeal of a ban on swimming pools and a long-term contract to sell water to the two country clubs to keep golf courses green has spurred a debate between incumbents seeking re-election and their challengers.