Construction to widen the Santa Maria River Bridge will result in northbound Highway 101 traffic south of Nipomo being rerouted onto newly constructed lanes over the next two nights, according to Caltrans.

The detour will occur from 7 p.m. Monday until 6 a.m. Tuesday, and again on Tuesday from 7 p.m. until 6 a.m. Wednesday.

This detour will then be in effect for approximately six months to allow for the resurfacing of the northbound lanes.

Cyclists traveling south can detour along Thompson Avenue to Highway 166 East to Bull Canyon Road to Donovan Road.

Cyclists traveling north can detour along Donovan Road to Bull Canyon Road to Highway 166 West to Thompson Avenue.

Caltrans is cautioning cyclists to be aware of limited shoulder space on the bridge during construction.

The project will widen the bridge from two to three lanes in each direction, and will include a bicycle path near the southbound lanes behind a concrete barrier.

In addition, all traffic lanes will be resurfaced.

The contractor for the $31 million project is Flatiron West Inc. of San Marcos. Construction is expected to be completed in early 2014.

AnnMarie Cornejo is a reporter with the San Luis Obispo Tribune. Contact her at acornejo@thetribunenews.com.