As Hurricane Lane approaches Oahu, there are no safeguards in place if the Ala Wai Canal tops its banks and causes major flooding in Waikiki and the surrounding areas.

The Army Corps of Engineers and state Department of Land and Natural Resources have been working on a plan to mitigate flooding in the event of a major storm since 2001. In July, Congress appropriated $345 million toward that effort, but work hasn’t begun.

Asked whether state officials were monitoring the canal as Hurricane Lane fast approaches, or had a plan in place in the event of a flood, DLNR spokesman Dan Dennison said that the only active measure involved clearing debris from the state-controlled waterway.

DLNR’s Division of Boating and Ocean Recreation has instructed its contractor H.E. Johnson to clean debris from a trap at the bridge on Ala Moana Boulevard as soon as possible after the storm passes, he said. The trap is in place to limit upstream debris entering the canal from flowing into the harbor and ocean.

Army Corps officials couldn’t be reached for comment Thursday. But the corps has warned for years that a major storm, or so-called 100-year flood, could cause major damage to Waikiki, knocking out the state’s major economic engine for an indefinite period of time and putting life and property at risk.

A major flood could damage 3,000 structures and cost more than $1 billion in repairs, according to corps estimates. It’s not clear how significant a threat Hurricane Lane poses to the canal, but its approach from the south is particularly worrisome.

Karen Ah Mai, who leads the Ala Wai Watershed Association, a community group that for years has advocated for flooding controls, said that she’s concerned about the direction of the storm and the heavy rain.

“It’s going to be a lot of water, and I’m going to be watching it for sure,” she said.

The canal has topped its banks and caused flooding in Waikiki before — during storms in 1965 and 1967, as well as during the passage of Hurricane Iniki in 1992.