Endangered Watershed

Aerial tour underscores danger to water supply on which Rim Country depends


The long, narrow Blue Ridge Reservoir holds some 14,000 acre-feet, but two years of drought have left it half full, although mechanical problems have shut down Salt River Project’s pumps.

The long, narrow Blue Ridge Reservoir holds some 14,000 acre-feet, but two years of drought have left it half full, although mechanical problems have shut down Salt River Project’s pumps. Photo by Andy Towle. |

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The dry and spindly forest rises and slopes across the terrain, an unbroken ocean of trees crowding right to the edge of a sinuous snake of aqua-blue, with a shed skin of raw, exposed rock.

Rim Country’s future lies beneath that unbroken canopy of tinder dry trees and along the twisted banks of that canyon-caught Blue Ridge Reservoir, as revealed this week during a helicopter tour hosted by the Salt River Project.

From any street corner in Payson, the reservoir seems distant — almost hypothetical. However, the whole region’s future growth now depends on the town’s ability to complete a $34 million pipeline to double the town’s long-term water supply — and the future capacity of that now half-empty reservoir.

The helicopter flight underscored the intimate connection between the reservoir and the political and physical geography of Rim Country.

Recent developments have underscored that connection as well, from Payson’s struggle to finance the hefty construction bill now that water impact fees have dried up, to the upper East Verde riverbed left bone dry by the shutdown of the SRP pipes due to a failing pressure valve.

Perhaps most urgently, one of the hottest, driest years on record has left the thickly overgrown forest on the Blue Ridge watershed vulnerable to wildfires that could send mud sluicing into the half-full reservoir, permanently reducing its storage capacity.

The tour followed the bed of the East Verde from Payson all the way up the already fire-scarred canyon in the face of the Mogollon Rim from which the streams that normally feed it originate.

Decades ago, the mining company Phelps Dodge built a dam on East Clear Creek that created the Blue Ridge Reservoir. The company then installed pumps to get the water out of the deep, narrow canyon and into a pipeline that ran across the forested Rim to a giant water tank, which then sent the water rushing down another pipe to a hydroelectric generator at Washington Park. After passing through the generator, the mining company released the water into the East Verde as part of a deal with the Salt River Project. The mining company swapped the water from Blue Ridge for water rights SRP controlled for use in its mining operations in eastern Arizona.

Eventually, the mining company traded the whole Blue Ridge system to SRP for water rights elsewhere. Acting on a directive from Congress, SRP then struck a deal with Payson. That deal bars Payson from drilling any new groundwater wells in return for 3,000 acre-feet annually from Blue Ridge. The legislation also set aside 500 acre-feet for other northern Gila County communities, but so far, only Mesa del Caballo has negotiated a buy-in to the pipeline. The deal will more than double the water bills in the little, unincorporated community, but should also end water rationing and boost property values.

Before securing rights to Blue Ridge, Payson had the toughest growth limits in the state, imposed as a result of the alarming drop in well levels. Those wells produce about 1,800 acre-feet per year, with the once-controversial Tower Well in Star Valley capable of producing another several hundred acre-feet, although Payson has rarely tapped into that potential.

The Blue Ridge water will therefore more than double Payson’s water supply. The town intends to run the pipeline nine months a year and, at least initially, put a large share of the water back into wells to recharge the water table. The town estimates that the Blue Ridge water will supply an eventual population of 38,000 or more.

So far, Payson and SRP have spent millions upgrading the facilities on top of the Rim. Moreover, Payson is close to awarding contracts for the start of construction for a new, 15-mile-long, $34 million pipeline that will run along Houston Mesa Road from Washington Park to a not-yet-built $7 million water treatment plant next door to Mesa del Caballo.

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The mining company Phelps Dodge built this dam, which holds back the long, narrow, now half-empty Blue Ridge Reservoir. The lake can hold up to roughly 14,000 acre-feet, which includes some 3,500 acre-feet allocated to Payson and other northern Gila County communities.

The aerial view illustrated the fitful bounty of the East Verde, since SRP several weeks ago shut down the pumps on the existing system due to the breakdown of the pressure control valve. SRP sent the broken brass valve to a high-tech machine shop, where engineers will fashion a new valve from a block of steel. The valve regulates the flow of water down the steep pipeline into the turbine that generates the electricity needed to pump the water out of the reservoir atop the Rim.

Once upon a time, the East Verde flowed almost year-round along its length thanks to a wealth of springs releasing water that originally fell as rain and snow atop the Rim. However, a century of cattle grazing and fire-suppression atop the Rim resulted in a hundred-fold increase in tree densities. As a result, the thirsty thickets of trees atop the Rim now suck up much of the water before it can soak in past the root zone, reducing the amount of water that runs down the canyons or seeps into the spring. That has dried up many of the springs that once fed year-round streams gushing out of almost every canyon along the face of the Rim — including the East Verde.

The view from the helicopter revealed that without the supplemental flow from SRP’s pumps, the East Verde disappears underground for miles at a time. The creek has gone bone dry along much of its upper reaches through Whispering Pines. It re-emerges due to underground rock formations above Beaver Valley as it passes through Water Wheel, but then goes underground again just below Beaver Valley. The stream doesn’t emerge again until it reaches Flowing Springs, miles downriver. It flows sluggishly through East Verde Estates, then stays above ground through the deep canyon alongside Crackerjack Road, almost all the way to Doll Baby Ranch.

SRP officials note that because of the underground rock formations that line the riverbed all the way from Whispering Pines to the eventual junction with the Verde River, nearly 95 percent of the Blue Ridge water released at Whispering Pines makes it into the Verde River. From there, it flows into Horseshoe Reservoir, where it becomes part of the Valley’s water supply.

The helicopter ride also showcased the danger the thickly overgrown forest poses to Payson’s just-secured future water supply.

Ponderosa pines cover the entire Blue Ridge watershed so thickly that hardly a meadow or bare spot shows from the air. The accounts of early settlers describe a forest there with grass belly-high to their horses. Riders could gallop in a straight line for miles through the giant, widely-spaced trees — most of them 400 to 800 years old.

But overgrazing removed almost all the grass, which eliminated the low-intensity ground fires that once kept the forest open. Clear cutting removed many of the big, fire-resistant trees and a century of Smokey Bear crusading against fires replaced that open, fire-resistant forest with fire-prone tangles of trees.

The view through the window of the helicopter revealed an unbroken carpet of treetops, perfect conditions for a fierce crown fire able to spread from treetop to treetop. Such fires burn so fiercely that they consume every living tree and often sear the soil, creating a water-resistant crust of fused elements that make the soil “hydrophobic.”

Payson Ranger District head ranger Angie Elam, also on the tour of the watershed, noted that such fierce fires can work permanent changes in the forest. For instance, she said that ponderosa pines may never reclaim the steep hillsides charred by the Water Wheel Fire four years ago. The fire started near a popular camping area and only a lucky fluke of the wind kept the flames from consuming both Beaver Valley and Whispering Pines as it roared up slopes that hadn’t burned in a century. The fire dramatically increased silt and mud flowing into the East Verde and the slopes remain ghostly and barren. Only scrub oaks and chaparral brush has started to regenerate, with no sign whether the great mix of trees once there will ever return, she said. Fires on similar watersheds — like Four Peaks — have caused a permanent shift in vegetation types.

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