Santa Rosa Marathon to cause traffic disruptions

The Santa Rosa Marathon returns to local streets Sunday morning with more than 3,500 runners hitting the course for the 26.2-mile test of strength and endurance as well as the attendant events, a half-marathon and a downtown 5-K race.

Race organizers expect as many as 5,000 people to gather along the course to encourage the runners.

The event will impact local vehicle travel.

These are the schedule road closures:

Downtown loop, generally within the boundaries of Fifth Street to the north, Mendocino Avenue to the west, Sonoma Avenue to the south and Hope Street to the east.

Santa Rosa Avenue, 5-9 a.m.

Sonoma Avenue, 5-9 a.m.

E Street and D Street, 5-9 a.m.

First Street through Seventh Street, 5-9 a.m.

Mendocino Avenue from Seventh Street to Sonoma Avenue, 5-9 a.m.

Note: Brookwood and B Street will be open for drivers to proceed through the area.

County loop

This series of roads following the county portion of the marathon course and will be closed from 6-11 a.m.

Willowside Road

Guernville Road, 6-11 a.m. from Fulton past the Raley's supermarket to Lagune Frei Road.

Olivet Road

West Olivet Road

Oakwild Lane

Woolsey Road

Wood Road

Fulton Road will be one-lane south from Wood Road to Piner Road

Note: Through traffic to the west can use River Road or Hall