Caltrans is alerting motorists about around-the-clock one-way traffic control next weekend on State Highway 99 about 10 miles north of Gridley in Butte County.

Crews plan to conduct one-way traffic control from 8 p.m. Friday, Sept. 17, to 5 a.m. Monday, Sept. 20, in the Cottonwood Creek area.

Motorists may expect traffic back-ups and 20-minute delays during peak travel times. Caltrans advises motorists to use alternate routes.

Flaggers at each end of the construction zone will be utilized along with a pilot car. Motorists are reminded that pilot vehicles are to be followed at all times within the project zone for the safety of construction crews and travelers.

Failure to follow pilot vehicles may result in a $220 citation with traffic fees doubled in construction zones. The California Highway Patrol will be on site, monitoring traffic safety during construction.

The following weekend, Nelson Avenue will be closed at Highway 99 from 8 p.m. September 24 to 5 a.m. September 27. Nelson Avenue residents will be detoured to Highway 162 then to Wilbur Road to connect with Nelson Avenue.

The extended closures will allow crews to construct a new highway alignment leading to the newly built Cottonwood Creek Bridge. Teichert Construction of Sacramento is the contractor on the $8 million bridge project.

Weather or unexpected events may delay or postpone work.