People traveling or working in the Soscol Avenue/First Street area will have a front-row seat over the next seven months as a federal contractor builds the largest ditch that Napa has ever seen.
Work is about to start on the much anticipated Oxbow flood bypass channel — 1,300 feet long (a quarter mile), 200 to 300 feet wide and as much as 12 feet deep.
Traffic delays, at least one street closure and dust are some of the main public impacts from the Army Corps of Engineers’ effort to reduce flooding in the Oxbow and Soscol Avenue areas.
When finished, the channel will divert about half the water from a so-called 100-year flood.
The sides of the enormous ditch will be covered with concrete walls, while the bottom will be mostly turf-reinforced matting, with some sections of concrete. During dry times, it will serve as public open space — complete with trails, river access and places to gather.
Nordic Industries Inc., which was awarded the $12.5 million federal contract, held two informational meetings last week to let the public know about specific details of the work to come. Roger Lueck, a Nordic representative, said mass excavation of the channel will begin on the east side of the site, near McKinstry Street and the Napa Valley Wine Train parking lot.
“Throughout the major construction portion of the project, there will be some dust and noise from traffic and construction,” he said. “But hopefully we can minimize most of it by keeping it contained in the channel itself.”
The contractor will be digging up 150,000 cubic feet of earth and hauling most of it down Soscol Avenue to the Napa Pipe project site on Highway 221. Large trucks will be running continuously from 8 a.m. to 5 p.m., Monday through Friday, along designated routes.
Some 30,000 cubic feet of material will be relocated within the channel for landscaping, said Lueck.
“We’re looking at about 1,200 truckloads total,” he said. “That’s somewhere between 12 and 13 trucks per day hauling for a total of 60 working days. But if there’s going to be major disruption, we’ll warn the public in advance.”
One such warning will come when the company shuts down McKinstry Street for 45 days in the late summer to lower the street across the bypass. Sara Southam, owner relations and property manager of the Westin Verasa Napa hotel on McKinstry, said she’s not looking forward to that portion of the project.
“Construction is always tough to get through,” she said. “But at least the work isn’t occurring in our peak season.”
When hauling begins from the east side of the planned channel, trucks will enter the site off McKinstry, on the south edge of the Napa Valley Wine Train parking lot. They will load up and exit at the same location, travel north to Soscol Avenue and drive south to Kaiser Road — eventually dropping the truckload at the Napa Pipe site.
Later, on the west side of the project, trucks will access the bypass off the dead end of West Street, and drive east on Pearl Street to Soscol.
Nordic hopes that the majority of excavation and channel construction work will be finished by the end of November, leaving only landscaping and concrete and trail work through the following summer. The project is expected to be completed by June 2015, but Lueck pointed out that after Dec. 1, very little heavy construction will occur.
Nordic will also remove the redwood trees, which were trimmed in March to look like large toothpicks, and bury the trunks in the Napa Creek bank to create fish habitat.
“We trimmed the trees that way to prevent birds from nesting in them before we cut them down” Lueck said. “But everything you see will be 100 percent used.”