NORTH BEND — Emergency repairs to the Coos Bay North Jetty are expected to begin within the next few weeks. And it truly is an emergency.

Experts say the jetty could breach without immediate repairs. And some worry a channel could form north of the jetty from increased wave action hitting the coast.

The goal of the repairs is to ensure the integrity of three specific points that have deteriorated, particularly during last winter’s storms.

Everyone agrees the work needs to be done. But government officials and recreational users disagree about access to the North Spit.

Representatives from the U.S. Army Corps of Engineers and the U.S. Bureau of Land Management summarized the who, what, when and why of the project at the North Bend Public Library on Wednesday.

Natalie Richards, the project manager, said Corps personnel determined there is a 50 percent chance the jetty could breach. Worse yet, the North Spit just north of the jetty is at risk of eroding away.

The jetty preserves the shipping channel by blocking sediment buildup. Because of the weak points in the jetty, wave action washes away sand from the beach and eats away at the coast on the bay side. If left to its own devices, the ocean could create a new channel north of the jetty, undercutting the jetty’s usefulness.

The solution involves patching three locations near the sandy portion of the North Spit, including the  easternmost end of the jetty, with 45,000 tons of stone. A more permanent repair is slated to begin in 2013, subject to getting funding from Congress.

Richards said she expects the Corps will hire a contractor for the project today, with preliminary work beginning next week. She could not say for certain when work would begin on the North Spit, though she said it is tentatively scheduled to start Sept. 15.

When the work begins, about eight sand trucks will ferry stones from a staging area at the parking lot leading into the South Dike and Foredune roads. Both routes will be closed for the duration of the project, Richards said. Access to the beach will be restricted to foot traffic from Horsfall Beach.

Several users of the North Spit were unhappy with this arrangement. They asked if they could drive along the road hugging the edge of the bay to get to the beach near the North Jetty.

Richards would not relent.

“You aren’t even supposed to be there. It is federal land,” she said. “We understand you want to surf right in there, but our issue is public safety. It’s not advisable for you to be anywhere near there.”

She noted the trucks are the width of the road and as high as the dunes they will drive next to. They also are hard to slow down if something comes across their path, she said.

“There’s going to be a lot of equipment out there,” she said.

Coos County Chairman John Griffith, a longtime surfer himself, said he agrees the work is important and must be done, but he suggested the public would demand access.

“It’s why people live here, some of them,” he said. “And that’s the best time to be here.”

“And that’s the only time we can be there,” said Richards in response. The Corps is only allowed to transport the stone between Sept. 15 and March 14, when snowy plover are not in residence.

Dennis Turowski, Umpqua field manager for the BLM, said efforts would be made to give access to the public as much as possible. If work crews get time off around Christmas, then the roads could be opened. Or, should the contractor decide not to work on weekends.

The need to transport stone across the North Spit might have been averted had the Corps been able to bring in stone on barges. The National Marine Fisheries Service had requested a detailed study of impacts on aquatic species, and such a study would have been too costly and time-consuming, Richards said.