It's time for the North Shore, one of the largest communities on O'ahu still without a centralized sewage system, to take on the issue of cesspools.

City officials today will launch a yearlong planning process that could result in fewer cesspools in the area from Turtle Bay to Mokule'ia with its 18,000 residents and 2 million visitors a year.

Cesspools leach waste into the ground, and, with many North Shore homes built near the ocean, there is a potential the waste could leak into the sea.

"One thing I'm very clear about is nobody on the North Shore wants an ocean outfall anywhere," said Bob Leinau, a North Shore Neighborhood Board member.

North Shore residents rely on cesspools and septic systems to process household wastewater.

An Environmental Protection Agency mandate shut down large-scale cesspools across the nation in 2005, and the city no longer issues permits for them for residential use.

But North Shore residents already have made it clear they don't want a large treatment plant like those that serve Windward O'ahu, Honolulu and 'Ewa.

City officials say one plan for the North Shore might be several smaller treatment plants to help minimize the risk of failures.

"We know we're not going to build a Sand Island Treatment Plant," said Bill Brennan, city spokesman.

Residents have a chance to get involved in the planning beginning at this morning's meeting.

The wastewater treatment plan that eventually emerges could affect everything from development to water quality in the coming decades.

Leinau welcomed the planning process and stressed the need for residents to become educated about the treatment systems and what they can do to improve the North Shore.

An environmental consulting company, Brown and Caldwell, hosts the first public meeting today. "They'll be helping the group look at all the different wastewater technologies that might serve the needs of the region over the next 10 to 15 years," said Leland Chang, project coordinator.

The city is reversing its usual process and involving the community at the start, said Brennan.

"We're trying to have them even more on the front end," Brennan said. "We're meeting with a community working group who will advise the consultant on what should be built and where, which is the opposite way we usually do things."

Blake McElheny, a North Shore Neighborhood Board member, wonders if any centralized system is necessary since there have been few beach closures because of sewage spills.

An informed decision about what system to use requires research and studies about water quality, McElheny said, adding that the community doesn't know if it is at risk, and if money is spent, whether it will benefit the community or a few big landowners.

"Truthfully, I believe that there may be interests on the North Shore, and I'm talking possibly about major landowners, that will benefit from a municipal sewage collection system in the sense it will be easier for them to develop residential subdivisions," he said. "If we're trying to benefit the public, then we should know what kind of improvements we're expected to see in the water quality."

Reach Eloise Aguiar at eaguiar@honoluluadvertiser.com.