SUNSET BEACH — For the second time in seven years, the city's plans to complete a well-used bike path from Pupukea to Sunset Beach have been canceled because of unexpected problems.

But this time, the discovery of erosion control problems has doubled the price of constructing a 700-foot extension of the path to $300,000, leading some residents and officials to wonder whether it will ever get done.

"This is one of those that's nice to have but we feel it's too expensive," said Michael Oshiro, chief of the Traffic Engineering Division. Bicyclists now swing out onto Ke Nui Road and will have to continue doing that, Oshiro said. "Ke Nui Road is a residential street with limited traffic so we don't feel it's a safety issue between the bicyclists and motorists."

But Rex Dubiel, who has championed the project since 2000, said Ke Nui, which runs parallel to Kamehameha, is heavily used by surfers who come to the North Shore in their vehicles.

Dubiel said she couldn't overstate the need for the bike path with the millions of tourists that pass through the community every year. More than half of the visitors to the island drive to the North Shore, she said, adding that with those kind of numbers, children's safety is a major concern.

"We shoulder so much tourist traffic and so many cars," Dubiel said. "It's not a safe passage on Ke Nui Road."

She said the 3.5-mile bike path that runs along the entire coast of Sunset Beach and Pupukea is one of the busiest on the island.

The Ke Ala Pupukea bike path was constructed in 1995, according to the city. Most of it is off the main highway, but it does travel along Kamehameha Highway at Ke Waena Road for a short time. There are several gaps in the route where bikers are forced to use Ke Iki and Ke Nui roads, but for the most part it is an isolated thoroughfare.

The meandering asphalt path is a haven that dips and turns, taking riders under trees and past gardens planted by community residents.

Dubiel, a vice president of the North Shore Outdoor Circle, said this extension project was funded and ready to install seven years ago. The contractor won the bid for three bike projects and he had applied for a single permit for all three, she said. One of the paths held up the permit and eventually all three projects lost their funding, Dubiel said.

This time the design didn't take into account an erosion issue that was not included in the contract, Oshiro said.

"It might have been an oversight," he explained.

At a community meeting, City Councilman Donovan Dela Cruz's office indicated that he would initiate another request to complete the project.

But Richard Torres, deputy director for the city Department of Transportation Services, held out little hope for the project.

Torres said the city is funding bike paths in other areas that need them more, including at the University of Hawai'i, where ridership is greater and safety is more of an issue.

"The cost benefit to really do this 700 feet at that amount is quite extensive," he said.

Reach Eloise Aguiar at eaguiar@honoluluadvertiser.com.