The new on-ramp from westbound E. Washington Street to northbound Highway 101 will open at 5 a.m. Wednesday, Sept. 25, according to Caltrans spokesman Allyn Amask. No changes will be made to the on-ramp for eastbound motorists on E. Washington Street.

Leading up to the new on-ramp,  northbound loop on- and off-ramps at that interchange will be closed Tuesday, Sept. 24, from 10 p.m. to 5 a.m. One lane of E. Washington Street in each direction also will be closed from 8 p.m. to 5 a.m.

After the new northbound ramp is opened, Caltrans will reconfigure the northbound off-ramp to E. Washington Street and continue work on the southbound on-ramp.

Caltrans urges caution at motorists adjust to changes on westbound E. Washington Street that include reconfiguring the two left lanes as through lanes, adding a bike lane and, on the far right, a lane leading to the northbound on-ramp.

·        Motorists will no longer turn left at the intersection to reach the northbound loop on-ramp. Instead, motorists will merge right to use the northbound U.S. 101 on-ramp.
·        When turning onto westbound E. Washington Street from N. McDowell Boulevard or S. McDowell Boulevard, motorists must merge right to enter the new northbound U.S. 101 on-ramp. The existing left turn pocket from westbound E. Washington Street to the northbound U.S. 101 on-ramp will be eliminated.
·        The left turn pockets from east bound E. Washington Street to northbound N. McDowell Boulevard will be lengthened to increase storage capacity.
·        Pedestrians will continue to use the sidewalk on the south side of E. Washington Street, as there is no sidewalk on the north side of E. Washington Street.

Lane closures at Hwy. 101, Lakeville Road, Petaluma Blvd. South

From 10 p.m. to 5 a.m. Thursday, Sept. 19, Caltrans will close the northbound U.S. 101 on- and off-ramps at State Route  16/Lakeville Road to realign the northbound on-ramp.

From 11 p.m. to 6 a.m. Thursday, Sept. 19, Caltrans will close one lane of northbound Highway 101 from just north of the Sonoma County line to the Kenilworth Pedestrian Overcrossing. One southbound lane will be closed from 10 p.m. to 4 a.m. Friday, Sept. 20.

Full freeway closures will be necessary Tuesday-Friday, Sept. 24-27, at the Petaluma Boulevard South / Highway 101 interchange for bridge construction.

Northbound Highway. 101 will be closed from 11:59 p.m. to 6 a.m. Tuesday and Wednesday, and perhaps Thursday if work isn’t completed.

Southbound Highway 101 will be closed from 10 p.m. to 4 a.m. Thursday and 11 p.m. to 6 a.m. Friday.

For more information about the project, visit or follow Caltrans District 4 on Twitter @Sonoma101.