Homeowners can be held financially liable if improper care of their portion of the stream leads to damaging floods, and the city wants to remind them about that.

At a news conference yesterday, Mayor Mufi Hannemann introduced the Clean Stream educational campaign that outlines stream maintenance laws and offers suggestions about maintaining waterways.

October marks the second anniversary of a flood that devastated parts of Manoa Valley, causing millions of dollars worth of damage. Because tons of debris in the stream had clogged passageways, water overflowed the stream banks and poured into the community.

Like other waterways in the islands, Manoa Stream has many owners, including the state and private citizens. The city is hoping to convince them all to participate in the effort.

The city says stream owners have a duty to maintain, dredge and clear their stream, and if they don't the city can step in and do it. However, the owner will have to pay. Fines up to $500 a day can be assessed for violating the maintenance ordinance.

The Clean Stream pilot program, to kick off in Manoa, is designed to help landowners whose property includes or abuts streams prevent potential flooding, Hannemann said.

With the city emphasis on basic services and responsibilities and the stepping up of efforts to ensure those are taken care of, the city wants state and private landowners to take responsibility for their properties and do their part in the protection against flooding, he said.

"What I'm trying to avert here is a situation whereby we're going to be called upon to expand our responsibilities in areas that are not city property," Hannemann said. "I feel rather than wait for that to occur and get into the finger-pointing situation, let's be very clear now."

Helen Nakano, with Malama O Manoa, said ownership is a big hurdle to maintaining the streams because people own to the middle of the stream. At one time, residents had suggested that the city take ownership of the streams but that went nowhere, Nakano said.

Malama O Manoa does regular stream cleaning in Manoa but more needs to be done, she said, adding that it can't be done because ownership is so scattered.

"It's not a simple matter of everybody cleaning up," she said. "That's not going to go very far or very long."

Nadine Nishioka, chairwoman of the Manoa Neighborhood Board, welcomes the effort and said education should be done year-round, not just on the anniversary of the flood.

For the past two years, schools, organizations and neighbors have been spreading the word about flood causes and people are more vigilant about litter and debris, she said.

Even the city has been quick to respond to reports of problems, Nishioka said.

People haven't forgotten and even during a planning meeting for the new library, residents questioned the wisdom of building underground parking because of flooding possibilities, Nishioka said.

"So flooding is still on everyone's mind," she said.

Reach Eloise Aguiar at eaguiar@honoluluadvertiser.com.