Shoring up river flooding concerns
Over about 200 miles extending from its headwaters at Ebbetts and Monitor passes in the Sierra to the Stillwater National Refuge, the Carson River has provided a lifeline to generations of Nevadans.
Those who are experienced with the river’s history are well aware, however, that the river’s flow has not always been so peaceful. Raging floods have been documented, most recently in 1997, when heavy snow followed by heavy rain brought devastation around Northern Nevada.
Nearly 20 years later, Tod F. Carlini, in his dual role as East Fork Fire Protection District Chief and director of Douglas County Emergency Management, along with community members are working to minimize the impact of a repeat event in Carson Valley and beyond. Concerns fueled by four years of drought conditions that resulted in vegetation overgrowth and a build-up of debris along both forks of the river led to implementation of the Carson River Flood Event Planning Project, which saw completion of its initial phase this spring.
“How this all started was the concern over El Niño,” Carlini said. “We were kind of concerned about the flood potential for the river, and quite honestly, we were spurred on a little bit by one of the local ranchers, Clarence Burr, who had some genuine concerns about the condition of the river system.”
The result was a community meeting in December to identify problem spots.
“Chief Carlini wanted to get an idea where the possibility of flooding (existed) because at that time we were already starting to get some heavy snows and we were all concerned about the spring runoff,” said Norman Harry, program director for the Washoe Tribe Environmental Protection Department.
To an eye trained by flood experiences, the potential for disaster was easily visible.
“You didn’t have a lot of water coming through, doing natural scouring and removing some of the material,” Carlini said. “The concern was that along the entire river system, the channel capacity was either impeded or it was made smaller because of the deposits of material or rock and sand.”
Lessons learned from 1997 were called on to help identify potential points of flooding along the river.
“We kept coming back to the ’97 flood, so we felt one of the key components to really understanding this would be to bring in people that had a relationship or connection with the river,” Carlini said. “We had about 24 people or so come in and they mostly turned out to be some of our older representatives in the ag community — Fred Stodieck, Andy Aldax, Gary Aiazzi, Bob Chichester, Julian Larrouy, Brett Reed — people that had experience, they had seen it, understood it and knew what had happened.”
Stodieck is one of five Douglas County representatives on the Carson Water Subconservancy District board of directors. In 2008, the agency’s Watershed Floodplain Management Plan was adopted by six counties along the river — Churchill, Lyon, Storey, Carson City and Douglas in Nevada, in addition to Alpine County in California — to establish long-term goals and objectives for floodplain management.
Harry credited Washoe ranch managers Stan Smokey and Reed for contributions they brought to the conversation.
“They were a huge benefit to me just because they were able to provide a lot of historical information,” he said.
Initial discussions didn’t revolve around engineering, but rather was based more on personal knowledge and information.
“We projected the river system in sections up on the map, passed around a laser pointer and they pointed out spots from the power dam all the way to Cradlebaugh on the East Fork. Then we did the same thing on the West Fork,” Carlini said.
Carlini said a list of 50 items identified future projects that needed to be addressed. Topping that list was a half-mile restoration project on the East Fork between Washoe Tribe land south of the Carson Valley Golf Course, a major breech point in 1997, in addition to a site where significant land loss had occurred to Tribe lands due to bank erosion and instability.
“There was a build up of gravel bars and a lot of dead fall,” Harry said. “We had almost eight to 10 feet of build-up of sand and gravel and dead fall. The idea was to essentially do a widening project to alleviate high flows and to disperse the energy that’s coming down the river.”
Craig Burnside, who retired as Douglas County Parks Department superintendent in October, only took a short break before he resurfaced as river-grant coordinator for the Carson Valley Conservation District at the start of 2016.
Burnside said Nevada Sen. James Settelmeyer, R-Minden, provided guidance that helped the conservation district solicit $100,000 in funding, about half of the total needed for the project.
“There is a fund that was established through the legislature a number of years ago, the snag and clearing fund, just for doing maintenance on rivers,” he said.
He added that the rest of the funding came from various sources such as Douglas County, the Allerman-Virginia Canal Company, Gardnerville Town Water, the Gardnerville Ranchos General Improvement District, the Carson Valley Medical Center and the Carson Water Subconservancy District
“It was truly a community event,” Burnside said. “And I think by the time it was decided ‘We need to get this done,’ that was in December and the project was done by early March,” Burnside said. “It took about three months, which was amazing.”
Carlini added that the Carson Valley Golf Course paid for the permits through the Nevada Division of Environmental Protection.
“The good thing about all of this, we brought these people together and it was one of the best experiences I’ve ever participated in here in terms of people forgetting who they represented and were looking at this whole problem as belonging to everyone,” Carlini said.
MORE WORK REMAINS
“This was a huge success, but as Tod pointed out, there were just under 50 problem areas that were identified along the river from the old power dam down to Cradlebaugh,” Burnside said.
And there are no guarantees that a repeat of the ‘97 will not occur.
“You’re still going to have that potential for those types of flood events, but you can do things that will help mitigate the impacts,” Carlini said.
Harry described the collaborative effort as a success.
“It was nice to see the project completed on time and within budget,” he said. “I think there were some lessons to be learned, but I think the most important thing is that everybody was working together as hard as they possibly could to make this thing happen before the spring runoff.”
Carlini acknowledged additional work on the river such as a recently-completed $1.6 million Nevada Department of Transportation project to buttress Cradlebaugh bridge on Highway 395. Two bridges cross the Carson River and two cross the adjacent Cradlebaugh Slough were seismically retrofitted with approximately 20,000 pounds of reinforcing steel and other improvements for enhanced safety and stability during potential earthquakes. Roughly 8,000 cubic yards of rock was also placed in the riverbed to reduce future erosion of the bridge supports.
“Little by little, we’ll get there because as we also improve some of the river channel areas and do some of those things,” Carlini said. “Flows are going to go through and some of the natural processes are going to start taking place that we haven’t had for a long time.”