Large snowpack and high river bring water safety to forefront

Even with a “blurry” crystal ball for predicting weather, temperatures and precipitation will determine impacts to communities along the Carson River heading into summer. The threat of flooding looms, but actual flows in and around Carson City could remain in the realm of high, fast-moving water without major flooding. One thing is certain: a huge remaining snowpack in the Sierra Nevada will make the river dangerous in the coming weeks.

“One thing I would point out is the flows on the Carson River are going to be very high for a long period. The water will be cold and moving fast. People need to be careful around the river,” said Ed James, general manager of the Carson River Subconservancy District.

James doesn’t foresee major flooding upstream of the Lahontan Reservoir unless there’s a major heatwave.

“As I look into my crystal ball, which is very blurry, this is what I see the runoff will be for this spring,” he said. “Based on 1983 and 2017 snowpack and runoff, I do not anticipate any large flooding on the Carson River upstream of Lahontan Reservoir. We will experience some very high flows and some minor flooding in the lower lying areas. This is based on historic norms, which this year is anything but normal. If we get some very hot or wet weather over the next two months, we could see some moderate flooding.”

Jeff Anderson, hydrologist for the Natural Resources Conservation Service in Nevada, pointed out how much snowpack remains at the headwaters of the Carson.

“The Carson Basin’s snowpack peaked on April 9 with an average of 59 inches of water content based on the SNOTEL sites in the basin,” he said. “This amount was 284 percent of the normal (median) peak and surpassed the 2017 by 10 inches. As of May 1, the basin average snow water content stood at 48.7 inches, which means 83 percent of the basin water content remained to melt.”

Anderson said most of April’s melt occurred at lower elevations.

“Spratt Creek SNOTEL at 6,063 feet elevation is the only SNOTEL that is currently melted out,” he said. “Normally other sites such as Monitor Pass would also be melted out by this time of year, but it still has 6 feet of snow on the ground waiting to melt.”

Anderson said the NRCS produces streamflow forecasts for total volume of water over certain periods. For example, roughly 500,000 acre-feet of water are expected to travel through the Carson River corridor in Carson City from May to July.

“Our forecasts indicate that this year’s runoff from now through July will very likely break previous records for the East Fork Carson near Gardnerville, the West Fork Carson at Woodfords and the main Carson at both Carson City and Fort Churchill,” he said.

However, NRCS forecasts don’t provide guidance on “peak discharge magnitude or timing.”

“Peak flows are generated by either rapid snowmelt or rain or both which depend on future weather,” he said.

Anderson pointed to river forecasts produced by the U.S. National Oceanic and Atmospheric Administration as tools with which to gauge short-term flows. The forecasts can be accessed online: https://www.cnrfc.noaa.gov/. As of Monday, the Carson River in Carson City is projected to stay below monitor stage of eight feet through Saturday. The river hit 7.4 feet on May 3. According to the National Weather Service, temperatures are expected to warm this weekend to 5 to 10 degrees above normal.

“With the warmer temperatures, snowmelt will once again start to become enhanced with a return of higher flows to rivers, streams and creeks,” said the NWS Reno office.

Local first responders are preparing for the runoff as well. On May 5, members of the Carson City Fire Department met in Brunswick Canyon to train for swift water rescue. The river was swollen and running at about 2,500 cubic feet per second. Days before, during a warm spell, it was running above 4,000 cubic feet per second, according to CCFD Driver Operator Craig Cook.

Cook said during a similar training last year, the river was at 300 cubic feet per second.

“The most dangerous part about our river — which is even more dangerous than other ones — is there are so many strainers on our river,” he said.

Cook pointed to trees and bushes as potential “strainers.”

“A strainer is anything that water can go through that you cannot,” he said. “Think of like a branch hanging in the water. If you come up on that, it holds you there, and it basically drowns you.”

For experienced kayakers and rafters looking to take advantage of high flows, Cook urged caution. He noted flows can change from day to day depending on weather.

“If you’re a rafter or kayaker, look at the river and the flow and preplan it,” he said.

Leaving Carson City, the Carson River flows through rugged canyonland, making access difficult in places. CCFD Firefighter Paramedic Bret Waszkiewicz stressed the cold temperature of the water.

“By the time we get here, you’ll be verging on hypothermia,” he said.

Sandy Wartgow, CCFD division chief of emergency medical services, provided another warning.

“If you’re going to get in the water, have a PFD (personal flotation device) on,” she said. “You’re not going to be able to control your body in this water. You have to have something that will keep your body afloat.”

Wartgow added, “Drinking (alcohol) and rapids don’t match up very well.”