Resubmerging a plastic sewage pipe that has floated to the surface of the Ala Wai Canal could take up to three weeks, but city officials reiterated Monday that the pipe is not leaking and poses no health risks.
The large pipe, which has been mistaken for everything from a log to the tail of a sea monster, emerged Saturday from the canal near the Hawai‘i Convention Center.
Blame warmer weather for creating more gas that caused the section of pipe to float, said Tim Steinberger, city environmental services director.
"Now that the weather has changed and such, and it gets a little warmer, you start getting gassing of the sewage, and so what has happened is all these fine bubbles have finally come together in one location," Steinberger said. "And over time it’s gotten so much gas in there that’s it’s caused the pipe to float."
To fix the problem, a collar will be put around the pipe section to control the flow of the gases; then the gases will be gradually released through filtering devices and probably routed to a sewer manhole across the street, Steinberger said.
Steinberger said he doesn’t know how much the repair will cost.
The 5,000-foot-long, high-density polyethylene plastic pipe was installed as temporary backup after the large Beachwalk force main broke in 2006, causing 48 million gallons of sewage to flow into the Ala Wai.
The pipe, which measures 48 inches in diameter on the outside and 42 inches on the inside, runs nearly the length of the canal from the community gardens in Kapahulu to Ala Moana Boulevard.
It connects with a 69-inch pipe that runs into the Ala Moana pump station.
"Right now all of the flows from Beachwalk run through the old force main. That’s our primary, but this is our backup so we want to make sure we do this right," Steinberger said. "We’ll probably be spending the next two to three weeks out here making sure this is done correctly."
There is "very, very low" risk of sewage seeping out of the floating pipe, he said. Little sewage was flowing into the pipe already, and that has now stopped entirely. "Right now it’s more of an eyesore than anything else."
The closing of the pipe will not affect construction of a new Beachwalk force main replacement project, which is scheduled to be complete by the beginning of 2013, Steinberger said. "When that is done, this pipe will be removed," he said.
Evelyn Hughes, who lives on the 16th floor of a nearby condominium, said when the pipe first surfaced Saturday, it was closer to the middle of the Ala Wai and closer to the convention center side of the canal. Monday afternoon the pipe appeared to have moved toward the Atkinson side and closer to Ala Moana Boulevard.
"It was longer and not as raised," Hughes said. "It was like a big tree trunk."
The commotion was not affecting canoe paddlers getting ready to take to the water at the Ala Wai.
Charity Kaina of Hui Lanakila said she expected her crews to paddle past it on the way to open ocean during practice.
Kaina said she didn’t know what to make of the pipe when she first saw it during the weekend. From a distance it looked like it may have been a whale.
"It was trippy because last week we didn’t see it," she said. "And then all of the sudden, it was like, What is that?"
