WAIKIKI (HawaiiNewsNow) - Imagine a flood that raised the level of the Ala Wai Canal just seven feet. It's possible, and engineers are working on a way to keep those waters from overflowing into Waikiki.
A flood that could happen once in a hundred years would damage more than 3,000 structures with a loss of $318 million.
"If we didn't have the project, most of Moiliili and McCully and almost all of Waikiki are underwater," said McCully-Moiliili Neighborhood Board member Ron Lockwood, who was among more than a hundred people who attended a public meeting on flood control measures at Washington Middle School Wednesday.
The Ala Wai did run over its banks in 1965 and again in 1967. And in 2006, torrential rain also brought the canal close to overflowing.
The U.S. Army Corps of Engineers has a $170 million project that would include building a four foot-high wall on the banks of the canal to prevent the flooding from flowing into Waikiki.
"We want to do it where it fits the aesthetics of the area," said Derek Chow, Chief of Civil and Public Works for the corps. "It also fits the historic district, because the canal is part of a historic district."
The plan would control floods upstream before they reach the canal.
"We are talking about small detention basins, may in a series, to reduce the actual size of each basin so that it doesn't have the potential to cause any harm if it was to fail," said Chow.
In all, the proposal includes six detention basins that would hold back excess floodwater in the upper reaches of Makiki, Manoa and Palolo Streams. There also would a debris catchment basin for Manoa Stream, along with multi-purpose detention basins in open space areas, such as parts of Ala Wai Park.
"I think they're doing something that should have been done a long time ago," said Barbra Accoutrement of the Diamond Head-Kapahulu-St. Louis Heights Neighborhood Board.
It has actually taken more than 15 years for the project to reach this point, and it could be another seven years before anything it actually built. Funding would have to be approved by Congress.
While it is impossible to say when construction could begin on the project, there is a Nov. 9 deadline to comment on the draft environmental impact statement.
Related Link: Ala Wai Canal Project