As the city prepares to open downtown streets to two-way traffic, it may pursue plans to construct two roundabouts and possibly reverse the directions of First and Second streets between Jefferson Street and California Boulevard.
Public Works Department staff said Tuesday it will ask the City Council this spring to add the roundabouts to the city’s Capital Improvement Project program, which covers pending projects over the next five years.
On Jan. 29, the city will hold a meeting at 6 p.m. in City Hall to get residents’ opinions on whether it should also pursue flipping the direction of First and Second between Jefferson and California as part of the roundabout project.
The roundabouts are the product of a $112,000 study the city commissioned in 2010 to look at traffic circulation west of downtown.
According to the study, conducted by Roseville-based Omni-Means LTD, emergency response times from the downtown fire station to Browns Valley Road and traffic flow could be improved with the installation of roundabouts and reversing street directions, making First eastbound and Second westbound between Jefferson and California.
The study looked at three scenarios: Making no changes, reversing the directions of the street couplet and opening First and Second two-way traffic, as is set to happen east of Jefferson in downtown.
Traffic counts, gathered from cell phones being driven through the survey area during morning and evening rush hour, showed that opening up each road to two-way traffic would worsen traffic flows, with First bearing the brunt of the traffic.
Reversing the direction of the streets would bring only minimal increases in vehicle trips to either street, and slightly reduce the number of cars on adjacent Third and Clay streets, according to Senior Civil Engineer Jason Holley.
With that information, Omni-Means explored how the addition of traffic circles would affect traffic.
Omni-Means said roundabouts on California Boulevard at First and Second streets would reduce the emergency response times to Browns Valley and improve the roads’ level of service.
These benefits would occur if the roads were left as they are now or if their directions were changed, according to a city staff report.
Thirty years down the road, roundabouts would provide even greater traffic relief, the city said.
“There is a need, as we look at future traffic projections for build-out, to do something at those intersections,” said Deputy Public Works Director Eric Whan.
With a traffic circle, motorists yield to those already in the circle and there is a continuous flow of traffic moving in and out, counter-clockwise, at a speed of \ 18 to 20 miles per hour.
Roundabouts typically don’t see the gridlock common at traditional intersections, city staff said. At a traditional four-way intersection, “only one leg of the intersection can go at a time,” Holly said. “When one guy is going, three are waiting, roughly. Everybody has to wait their turn and over time, you have a build-up of cars.”
Omni-Means President Ross Ainsworth cited studies to the council that show the safety of roundabouts, where fatalities are nearly nonexistent and collisions tend to be of the slow-speed, rear-end and side-swipe type.
Ainsworth went on to say that studies show most people have a negative view of roundabouts before they are installed, but hold a positive opinion once they have tried them.
Mayor Jill Techel joked about the notion that roundabouts would confuse visitors bound for downtown. “If we do roundabouts, it’s not like we haven’t confused them before,” she said, alluding to the current pattern of one-way streets.
Staff said the roundabouts would have sufficient signage and landscaping to prevent confusion. If someone happens to miss their exit, they may go around the circle an extra time and exit at the proper location.
Two downtown developers spoke in favor of making changes to the area. Peter Bartlett of Zapolski Real Estate, which bought the Shops at Napa Center last May after the city approved the Downtown Specific Plan, said the city needs to make it easier to access downtown from Highway 29.
“One of the crucial pieces of the Downtown Specific Plan and to us was the change in the circulation pattern downtown,” Bartlett said. “The piece west of downtown is also very important to all businesses downtown. ... Making it easy for inbound travelers to get to the downtown core commercial area of Napa is going to be critical to support the ongoing development that we’re experiencing in Napa right now.”
In the long term, the city could look at installing roundabouts farther west on First Street, at the northbound and southbound Highway 29 on/offramps and at the intersection with Freeway Drive. The hope is that such changes would eliminate the need to widen the First Street overpass, which is likely financially unfeasible, according to the city.
The cost of constructing the roundabouts at California Boulevard is $4.5 million, Holley said. Switching the direction of the couplet would cost an additional $1.5 million.
The city had previously estimated that replacing the First Street overpass would cost $60 million to $80 million.
Funding could come from federal, state and local sources and the city has already applied to the Napa County Transportation & Planning Agency for approximately $1 million in federal grants.
The project is one of many that department staff are drafting and will propose to the council as it develops its budget, likely in May, for the 2013-14 and 2014-15 fiscal years.