(Updated at 2:15 p.m.) A large stretch of the northbound George Washington Parkway will be shut down this weekend due to rock stabilization work.

All northbound lanes of the parkway will be closed from Spout Run to Chain Bridge. The closure is scheduled to be in place from 7:15 p.m. on Friday, Oct. 5, to 5:30 a.m. on Monday, Oct. 8, according to the National Park Service.

“Detours will be posted, variable message boards have been placed, but alternate routes are strongly advised,” NPS said.

One possible way around the closure for GW Parkway drivers is to take the northbound Spout Run Parkway to Lee Highway, Lee Highway north to Military Road, Military Road north to Glebe Road, Glebe Road northeast to Chain Bridge Road, and Chain Bridge Road north to back to the GW Parkway. Another alternative route, for drivers heading to the Beltway, is to take Spout Run to Lee Highway to westbound I-66.

The rock stabilization project is being performed through Dec. 19 by the Federal Highway Administration. The goal is to stabilize the “rock slopes” of two sites near Spout Run that experienced recent “rock fall events.” The second site, just north of Spout Run, had a boulder fall onto the parkway as a result of the Aug. 23, 2011 earthquake, according to FHA.

In addition to the closure this coming weekend, one of the three northbound lanes of the parkway near Spout Run is closed through the end of the project, and a second (middle) lane is closed during non-rush hours. On top of that, two additional full weekend closures are also planned this month.

“A second and third full weekend closure at the north slide is tentatively scheduled for the weekends of October 13th and 14th and October 20th and 21st,” according to the Park Service.

Photo via the Federal Highway Administration