Where to put the water?

Since December Lahontan Valley ranchers and farmers have been euphoric because of the increasing snowpack in the Sierra Nevada mountain range that will eventually fill Lahontan Reservoir.

Yet, water always presents itself with a good news, bad news scenario.

First and foremost, farmers expect to have a banner growing year with the abundance of water, something they haven’t seen since 2012 when the reservoir filled up.

Now, the bad news, especially for those who live downstream from the Lahontan Dam. Once the snowpack melts and sends cold mountain water rushing down the Carson River to Lahontan, the reservoir will rapidly reach capacity, thus triggering a plan to redirect water to mitigate any lowland flooding.

Water master Kelly Herwick of the Truckee-Carson Irrigation District is soon to become a genie with a magic ball once the water roars down the mountain.

“We’re now at a point to figure out the forecast of how much (precipitation) is in the mountain and how much will be coming into the Carson River,” Herwick said.

Because of the deep snowpack in the Sierra, which ranges upward to 26-feet deep in the Lake Tahoe Basin, Churchill County, state and federal officials are juggling with numbers and scenarios. Earlier this month, TCID officials shut off water from the Truckee River to the Truckee Canal, which also flows into Lahontan, because of an operating agreement. Bureau of Reclamation hydrologists constantly monitor the added accumulation of water. For the time being, water from the Truckee River will keep flowing into Pyramid Lake.

TCID relies on the lessons learned from previous years when flooding occurred downstream from the reservoir and through the Carson River corridor to the Carson Sink northeast of Fallon. If Herwick sees the reservoir filling up faster than predicted, he said Reclamation then guides TCID on precautionary drawdowns. TCID then follows a procedure to send extra water to the Stillwater National Wildlife Refuge in one or all three irrigation canals, marshes, reservoirs such as Harmon or Sheckler or Carson Lake south of the Greenhead Hunting Club on Pasture Road.

The fourth and final scenario, he said, is sending the water to the Carson Sink to mitigate any potential flooding in low-lying areas.

“In 2011, we had precautionary drawdown,” Herwick said, noting Lahontan Reservoir had about 191,000 acre feet of water on May 1. “We had quite a lot of storage with the reservoir. The drawdown worked out pretty good.”

Each acre-foot of water equals less than 326,000 gallons of water and is enough to cover one acre of land one-foot deep.

A similar scenario occurred during the winter of 1996-97 when a Pineapple Express weather pattern from the South Pacific moved over the Sierra in late December 1996, melting a substantial snowpack and sending water down the Truckee and Carson rivers that flooded low-lying areas from Minden to Fallon.

Rusty Jardine, TCID’s district manager, said his agency meets weekly with Reclamation via videoconferencing to discuss the forecast and modeling done to determine snow totals. Additionally, Jardine said TCID is constantly in contact with the National Weather Service.

Churchill County Sheriff Ben Trotter said similar concerns are occurring now as they did in 2011 with the spring runoff. He said the flooding upstream on the Carson and Truckee rivers combined with the Sierra snowpack are causing officials to evaluate the county’s readiness.

“We are asking for residents who live along the river to make sure you don’t have any cross fences in the river or obstructions that would block flow or collect debris when water is released into the river later in the year,” Trotter strongly advised.

Herwick said residents who live near the river should be aware of any structures or debris that could impede the river’s flow.

In 2011, Trotter and local officials issued the same advice and warnings about eyeballing the river and reporting any obstructions to TCID or the sheriff’s office.

Jardine said TCID has applied for a state permit to clear out the river channel of any debris and other obstacles from the Carson River.