Caltrans will close Petaluma Boulevard South and the northbound Highway 101 off-ramp to Petaluma Boulevard South on Sunday from 4 a.m. to 11:59 p.m.

• The demolition of the old northbound Highway 101 bridge over Petaluma Boulevard South is being completed in one day to avoid several nights of ramp and road closures.

• Residents may notice increased noise as work is completed above Petaluma Boulevard South.

• Detour 1 (east side of Petaluma Blvd. S. closure): Northbound 101 traffic that usually exits at Petaluma Boulevard South will be diverted to the next exit at Highway 116/Lakeville Highway.

• Detour 2 (east side of Petaluma Blvd. S. closure): Residents who live or work on the east side of the freeway or on Kastania Road can exit at Highway 116/Lakeville Highway, take southbound 101, and exit at Petaluma Boulevard South to access their residence or business.

• Detour 3 (east side of Petaluma Blvd. S. closure): During the closure of Petaluma Boulevard South, park and ride users, local residents, and businesses who want to travel north on 101 can take the southbound 101 on-ramp from Petaluma Boulevard South, travel to the Redwood Landfill interchange, and return to northbound 101.

• Detour 4 (west side of Petaluma Blvd. S.): take Petaluma Blvd. S., turn right on D Street, turn right on Lakeville Street, and continue to 101.

The work is weather dependent. If work on Feb. 8 is cancelled due to weather conditions, closures will be rescheduled for Feb. 10.