PORT ANGELES — Four-hour delays on U.S. Highway 101 around Lake Crescent will begin Monday, Oct. 30 and continue through late November for rock bolting work, Olympic National Park said.

The delays will be between 9 a.m. and 1 p.m. Monday through Thursday until the project shuts down for the winter.

Work began in the spring on the $27.5 million project to rehabilitate 12 miles of U.S. Highway 101 around Lake Crescent and East Beach Road. The National Park Service and Federal Highway Administration are managing the project.

During the four-hour delays, the turn for Barnes Point where Lake Crescent Lodge, Storm King Information Station, NatureBridge and trailheads are located will be accessible only from Highway 101 eastbound from Forks.

Highway 101 westbound from Port Angeles will be open to East Beach Road near milepost 232.

Those traveling through can use state Highway 112 and 113 as an alternate route.

During the four-hour delays, Clallam Transit’s Route 14 will continue all eight trips between Port Angeles and Forks — but not all will make the entire journey, according to Steve Hopkins, operations and planning manager.

Between the hours of the closure — 9 a.m. to 1 p.m. — the bus will travel from Port Angeles to East Beach Road while the bus from Forks will travel to Sol Duc hot springs stop. The buses will then return to their starting points.

This provides local service, such as to the Lower Elwha Health Clinic, Hopkins said.

The other six trips will go through.

Construction work will continue during the four-hour delays on other portions of the project outside the rock bolting area and travelers on Highway 101 at Lake Crescent should continue to expect half-hour delays Mondays through Fridays during work hours.

Traveling before 7 a.m. and after 7 p.m. might help travelers avoid the half-hour delays.

During the half-hours delays, Clallam Transit has suspended the 1:30 p.m. bus trips from Port Angeles and Forks, Hopkins said.

“Delays on the lake are now are so great that we can’t maintain a schedule,” that includes the 1:30 p.m. runs, Hopkins said.

Rock scaling work was completed during a complete Highway 101 closure Sept. 11-15. The current phase of work on the rock face is referred to as rock bolting.

Holes are drilled from 5 feet to 25 feet into the rock to secure weathered, less stable rock near the surface to structurally sound rock deeper within, park spokeswoman Penny Wagner said in a press release.

Surface rock is then secured to stable rock under tension with surface plate washers and epoxy inside the drilled holes.

“When complete, this work will significantly mitigate the rockfall hazard in this area,” Wagner said.

Additional safety measures are now in effect after two recent instances of property damage during rock bolting operations, one involving a failed drill rig anchor bolt, Wagner said.

No drilling or repositioning of drilling rigs will take place during periods of traffic movement, she said.

The park’s partner for this project, Western Federal Lands Highway Division, has “a high level of confidence that these new safety procedures will provide for safe public travel through the work zone,” Wagner said.

Maps of the area and current project information are available on the park website at http://tinyurl.com/PDN-101delays.