The Regional Transportation Commission received a preview of the South Carson Street Complete Streets Project.
The project is now 30 percent designed and on Wednesday the RTC voted to recommend the Board of Supervisors accept it.
The project covers nearly 2.5 miles of Carson Street, from Appion Way to 5th Street, and will reduce the roadway to two lanes in each direction with a center turn lane.
According to the design, the lane reduction starts north of Snyder Avenue. After Stewart Street, where there’s a proposed roundabout, the northbound side of Carson Street will reduce to a single lane, probably with a righthand turn lane for traffic turning onto 5th Street.
The roundabout is at about 15 percent design, said Dan Stucky, city engineer, because Kimley-Horn, the design consultant, was the last contractor to join the project.
The preliminary design calls for a single-lane roundabout with 10-foot or more offsets and rolled curbs to enable trucks to make the turn.
On the northbound side, the right-hand turnoff for Stewart Street will remain so travelers turning there won’t enter the roundabout.
Southbound will have a bypass lane so traffic traveling straight on Carson Street won’t enter the roundabout either.
Fairview Drive also will likely be re-striped so the three westbound lanes at the intersection will have one lane for a right turn only, a middle lane for going straight or turning left, and a third lane for left turn only.
One entrance to the frontage road, which will remain, will be realigned to be directly across from Rhodes Street.
Also, on-street parking may be added north of Stewart Street and the city is now considering where to place some pedestrians crosswalks along the road. The crosswalks would likely have pedestrian-triggered signals to cross one side of the street, a safe way station in the middle of the road, and then another signal to cross the other side of the street so traffic would only be stopped in one direction at a time.
“Between Koontz and Fairview there is no crossing so we need to have something in that stretch,” said Dirk Goering, senior transportation manager.
Another change will be a reduction in the speed limit. North of Stewart will probably be 25 mph while south of that will be 35 mph, although there may be a stretch at 45 mph, said Stucky.
Last month, city staff met with 248 businesses along the project corridor to talk about the work and potential impacts. Stucky said the project should be less disruptive than recent downtown work on Curry Street and Carson Street because there’s more roadway available to divert traffic while the street is under construction.
The city also scheduled a public meeting on the project for Dec. 11.
The city plans to have a final design approved by July and construction to start before the end of 2019.
The total project cost is estimated at $18.7 million. The bulk of the funding is coming from a $7.57 million federal grant and $6.25 million from the state. The remainder comes from five city funds, including $2.9 million from the stormwater fund.
