Two major road projects in downtown Eau Claire will kick off this week, but it means new detours will be in place.

Work on State Street will begin Wednesday, said city engineer David Solberg, from Bartlett Court to about 375 feet south of Hamilton Avenue. On Monday, Lake Street will be closed from Farwell Street to the Chippewa River Bridge.

The entire $3.5 million State Street project is about 5,200 feet in length — just shy of one mile.

“It’s our biggest project this year, with adding the three roundabouts,” Solberg said. “It’s a pretty big deal on city streets.”

A proposed fourth roundabout was rejected; Solberg will bring new plans to the City Council in July.

Phase one of the State Street project is about 3,800 feet long and is scheduled to be done by Oct. 11. The second phase will begin at that time and go through mid-November, as roundabouts are placed.

The State Street work will make the road slightly narrower, but will add a bicycle lane, as well as wider sidewalks. Underground utility work has already been going on for about a month.

The Lake Street project costs about $1.13 million, Solberg said.

“The pavement has deteriorated prematurely,” Solberg said. “We’re also realigning the turn lanes. And there is minor utilities work underneath.”

When finished, the street landscape will match other roads, he added.

“It will continue the pedestrian-friendly concept,” Solberg said.

Solberg reminded the public to watch out for detour signs and be aware of workers.

“We stress safety,” he said. “Follow the detour routes and don’t go around barricades. These are very big projects.”