Bulldozers, dumps trucks and an excavator will be on the move in Newell Open Space Preserve near American Canyon this summer, not building the area’s latest development project, but rather storm-proofing eroding trails.
Workers will use the type of heavy equipment seldom seen in a nature preserve to improve old ranch roads that serve as trails. One goal is to stop sediment during winter rains from washing from trails into creeks and ultimately the Napa River, possibly hurting fish habitat.
“This is a sediment-saving project,” said Bill Birmingham of the Napa County Resource Conservation District.
Another goal is to create a better Newell hiking experience. Erosion has taken a toll on the trail surfaces.
“It’s created a lot of cracks and ruts that have made the unstable soil surfaces hard to access at times and to be safe at times,” American Canyon Parks and Open Space Project Coordinator Shelan Zuhdi said.
Hikers will have be patient after Newell dries out from the rainy season and work begins. City Parks and Recreation Director Creighton Wright said trails in the lower reaches of the park up to the picnic area will remain open, but that the upper ridge trails will be closed.
The 640-acre Newell Open Space Preserve is owned and run by American Canyon. Hikers can head into the brushy hills and cross into adjoining Lynch Canyon Open Space Park in Solano County, enjoying views of American Canyon, wetlands, San Pablo Bay and a distant Mount Tamalpais along the way.
American Canyon and the Resource Conservation District are teaming up for the Newell sediment reduction effort.
“The old ranch roads of Newell Open Space Preserve were never quite constructed and implemented properly,” Zuhdi told the American Canyon City Council on April 2.
One solution is to add “rolling dips” of crests and troughs on the trails to spread out the drainage points. Water would no longer simply run down the trails, but would drain off at the dips. Dozens of rolling dips will be constructed.
The Newell Open Space Preserve sediment reduction project is hardly an experiment or novelty.
“We’ve been doing these types of projects for probably close to 10 years throughout the Napa River watershed,” Birmingham said. “I would say all of those are on private properties in general.”
For example, in summer 2016 the Resource Conservation District improved the roads at Enchanted Hills Camp and Retreat property in Wing Canyon on Mount Veeder. That effort was designed to keep 4,759 cubic yards of sediment – enough to fill more than 400 commercial dump trucks – out of local waterways over the next 20 years.
“Road systems are perhaps the most significant and easily controlled sources of sediment production and delivery to stream channels,” said a 2004 Resource Conservation District report on Wing Canyon Creek.
Too much sediment running off poorly constructed rural dirt roads and other erosion sources into waterways can hurt habitat for the Chinook salmon and steelhead trout. The Napa River watershed has been designated as critical habitat by the National Marine Fisheries Service for both species.
Jack and Bernice Newell donated the Newell Open Space Preserve land to the American Canyon in 1999 and the property opened to the public in 2014. The Land Trust of Napa County holds a conservation easement on the property that ensures it won’t be developed.
But the Newell property could have met a very different fate. Part of the site during the 1980s had been purchased by the American Canyon Development Co. to become a landfill, according to the city’s Newell management plan.
The Newell Open Space Preserve storm-proofing project is to cost about $90,000.
American Canyon is providing up to $25,000 for construction costs, after already paying about $9,000 for such things as a biological assessment. Money is coming from Measure A, the Napa County half-cent flood control sales tax that expired last year, a city report said.
Other money is to come from a Federal Clean Water Act Section 319 grant obtained by the Resource Conservation District.
The City Council on April 2 approved right-of entry and right-of construction agreements for the project with the Resource Conservation District. The District Board of Directors was scheduled to approve the agreements.