Monsoons Fail To Deliver

Salt, Verde rivers dwindle to one-third of their normal flows as summer rains bypass the Rim


Unless the skies open up soon, Rim Country will endure the second driest monsoon season in 110 years.

Payson normally gets about 22 inches of rain in a year, including 3 inches during August. But with October looming, Payson has had just 7.3 inches of rain since January — including less than half an inch in August.

Salt River Project meteorologist James Walter said the Salt and Verde river watersheds have gotten less than half their normal rainfall this summer — a parched 2.3 inches.

The high altitude winds that normally steer wet storms north from the Gulf of Mexico and the Gulf of California have veered far to the south. “The moisture is all staying down in Mexico,” he said.

The lack of runoff can be read in the flows as low as one-third of normal in the Salt River and Verde River — and the complete disappearance of Tonto Creek before it reaches Roosevelt Lake.

The bizarre rain patterns and “monsoon” summer rains have produced spot water shortages in communities that depend on shallow wells and an off-kilter fire season, with big fires burning late into the summer when afternoon rains normally douse them.

Some observers fear a return to the decade of severe drought that killed millions of trees, raised alarms about sustainable water supplies and nearly drained massive Roosevelt Lake.

However, Walter said an early shift to fall weather patterns could steer storms into the high country.

Moreover, warming surface water temperatures in the Pacific along the equator known as El Niño have set up the potential to produce a wet winter. However, Walter cautioned, for reasons no one understands, El Niños have failed to produce winter rain in Arizona for the past five years.

“Are we still in drought?” asked Walter, “that’s a tough question. It depends on your definition.”

A few months ago, Roosevelt Lake was brimming with water during a short, wet winter. However, it has already declined to 84 percent of its 1.4-million acre-foot capacity.

The reservoir continued to lose more than 2,500 acre-feet each day, nearly 500 of that from evaporation.

However, Walter said the system remained in “excellent” shape for this time of the year, since the reservoirs will likely refill as a result of the winter rains.

“No one is worried, not at all. We’re doing very well,” he said.

Still, the Salt River’s flow into the lake has dwindled to 125 cubic feet per second, about one-third of normal.

The Verde River at Tangle is holding up a little better, with a flow of 91 cubic feet per second, about 44 percent of normal.

Tonto Creek at this time of year normally has a flow of about 27 cubic feet per second where it merges with Roosevelt, but this week it remains bone dry.

The East Verde River has been at low flow for weeks, disappearing underground at places, to emerge downstream.

Normally, releases from the Salt River Project’s Blue Ridge Reservoir into the East Verde at Washington Park boost the flow substantially. However, SRP released water for a week or two at the start of the summer into the East Verde to pinpoint leaks in the pipeline on top of the Rim.

Water managers have kept the spigots closed since then while construction crews work on repairing the aging pipe to prepare it to receive Payson’s water supply, plus the 11,000 acre-feet SRP plans to release annually to replenish Verde River reservoirs supplying Phoenix.

Altogether, SRP’s reservoirs on the Salt and Verde have dwindled to 82 percent of their capacity, compared to 88 percent at this time last year.

Still, two relatively normal winters filled those reservoirs, providing several years of supply for the Valley, which consumes most of the water that flows through the Salt, Verde and Gila river systems, most of which never makes it past Phoenix.

Roosevelt’s 1.4-million acre-feet of storage accounts for most of the water in the system. Other Salt River reservoirs include Horse Mesa (1,906 acre-feet), Mormon Flat (1,657 acre-feet) and Stewart Mountain (1,542 acre-feet).

The two reservoirs near Phoenix on the Verde River hold about 3,500 acre-feet.


Use the comment form below to begin a discussion about this content.

Requires free registration

Posting comments requires a free account and verification.