Posted on July 19, 2016
By Howard Yune, Napa Valley Register
The long-awaited deepening of the Napa River should start as early as mid-September and last six to nine weeks, according to federal officials overseeing the waterway’s first dredging project in nearly two decades.
In a public forum Tuesday at the Napa Valley Yacht Club, the U.S. Army Corps of Engineers outlined more details of the project that aims to deepen a waterway where boaters have had to cope with increasing siltation since the last federally funded dredging in 1998.
The Corps project will remove sediment from sections of a 13-mile river stretch, from the Third Street bridge in downtown Napa – the northern limit of the navigable channel – south to Asylum Slough near Highway 37 in Vallejo. The work will produce a waterway with a minimum depth of 9 feet at low tide, concentrating on spots where the formation of shoals has created hazards to watercraft.
After the Corps chooses a dredging contractor, work should begin between the middle of September and early October, according to Corps project manager Pamela Patton. River work must be completed by Nov. 30 due to federal and state protection of salmon, smelt and other fish species.
Dredging will take place within the river’s federal navigational channel – 75 feet wide north of the Butler Bridge and 100 feet wide south of the span. Sediment will not be removed from the entire Napa-to-Vallejo riverbed but from areas with the shallowest low-tide depth.
Maps shown during Tuesday’s conference show extensive dredging planned for several northern sections including the downtown Napa dock and at Jack’s Bend near the yacht club on Riverside Drive, but only in smaller and isolated patches below the future Napa Pipe site.
Daily work will take place between 7 a.m. and 11 p.m. from Third Street down to Tulocay Creek, and 24 hours a day south of the Creek, Patton announced.
About 300,000 cubic yards of spoils pulled from the river bed will be deposited at two sites: one northwest of the South Napa Century Center and the other at the future home of the Napa Pipe housing development, north of the Butler Bridge on Highway 29.
Those living or boating by the river can expect to hear construction noises up to 90 decibels with sporadic spikes above 100 dB, said Corps project engineer Jessie Burton-Evans, who compared that level to “the average sound of a bulldozer or a loader.” Such noises would occur for a day or two in any given location before the dredging equipment is moved farther south, she told audience members.
A Napa-area boater and resident at the forum praised the belated dredging effort, though he also called on the city and county to enforce limits on speed and wake creation to further improve the boating experience.
“I was surprised when (the Corps) said they’d do it,” said Mark Dallman, a resident of the Milton Road area south of the city. “If they’d had container ships here, we’d have had no problem because they would be dredging like crazy.”
Although dredging traditionally had taken place in the Napa River roughly every seven to 12 years, the waterway in recent years had lost out on Congressional funding to busier waterways with more commercial and industrial traffic, officials said. An increase in shallow spots has complicated low-tide boating even for smaller vessels and, in December 2015, led the Napa yacht club to call off its Lighted Boat Parade due to shoaling problems.
City officials also hope to see an increase in Napa River traffic to and from the downtown dock, which it opened in 2013 near the north end of the boating channel. Napa in 2015 began negotiating with Tideline Marine Group to oversee daily dock operations and start a water taxi service to San Francisco and other Bay Area ports.
Source: Napa Valley Register