Sewage pollution warning signs are gone from most O'ahu beaches and people are returning to the water, but the state continues to monitor key sites and is working to improve how it gets the word out to the public.

A 48 million-gallon sewage spill into the Ala Wai Canal in late March and numerous smaller spills triggered by heavy rains prompted beach closures in Waikiki, East O'ahu and Windward O'ahu.

In the Ala Wai-Waikiki area, 103 warning signs were posted from Makalei Beach near Diamond Head to Point Panic at Kewalo Basin.

Many of the signs came down last month as water quality improved, but signs remained yesterday at Kualoa Beach Park and along the Ala Wai Canal and its outlet warning the public to stay out.

"As long as we can see the bottom, we think it's all right," said Yenlinh Tran, 37, who surfed at Kaiser's yesterday. "We've seen the warning signs (closer to the Ala Wai Canal mouth). We don't go over there."

State health officials continue to check water quality at more than a dozen sites in the Waikiki-Ala Wai area, but have scaled back from daily water sampling to twice a week.

Larry Lau, state deputy director for environmental health, said the department wants to make some changes in the way it gets information out to the public, such as holding daily news conferences and improving the Department of Health Web site.

There was a lot of interest from the public in knowing the bacteria counts for the various beaches that were closed but that data alone doesn't tell the story and other factors come into play when deciding to close a beach, he said. Lau said he would like to give the public additional information and let them decide.

Improving communication with hotels and giving more information to lifeguards are also being considered, he said.

"The thing we're going to work on first is clarifying when we warn and how," Lau said. "We want the public to be informed. We want the public to be protected."

Amy Brown, from California, said she put her trust in the state and has allowed her 13-month-old daughter to play in the water off Hilton Hawaiian Village every day of their visit.

"I figured if it wasn't safe they wouldn't allow us in," said Brown, who is on a business and vacation trip. "If they would have said, 'You can't go in,' obviously I would not have put her in."

Peter Okano, 49, said he ignored the sign and used his own judgment before going surfing yesterday at Ala Moana Bowls, which is close to the mouth of the Ala Wai Canal. He said his friends have been surfing there for the past two weeks and haven't come down with anything and added that the water didn't smell bad. He said he has surfed the area since the 1970s and that the Ala Wai has long been polluted.

"That sign will be up forever because the Ala Wai will be polluted forever," he said.

At Kualoa Beach Park, Mara Bland, a newcomer to Kane'ohe, said she missed the warning signs on the way to the water. Friends were visiting from Utah and one of them was in the water as she sat on the shore with the other. Bland said she thought it would be better to bring them to Kualoa because of the pollution problems in Waikiki, Bland said.

"We walked right between the signs," she said as she gathered up her things to leave.

The state needs to do a better job of warning and keeping people informed, said Bruce Anderson, president of Oceanic Institute and a former state health director.

Lifeguards should be updated daily so people at the beach can ask them about the water quality, Anderson said.

The state should form a response team similar to the kind it uses in emergencies, only this one would include University of Hawai'i specialists in such things as current movement, and federal ocean experts who can help project how spills will spread, he said.

"I think there was an opportunity lost here to learn more about the impact of sewage spills," Anderson said.

State tourism liaison Marsha Wienert said the industry is pleased that water quality is back to normal, but "I don't think anyone is going to be happy and unconcerned until the sewer lines are upgraded and fixed."

Reach Eloise Aguiar at eaguiar@honoluluadvertiser.com.