The Senate Committee on Ways and Means passed a bill Tuesday with amendments to allocate funds for a U.S. Army Corps of Engineers plan to lessen flood risks at the Ala Wai Canal.

The committee’s passage of the bill cleared a crucial hurdle for the project, which has been some two decades in the making. The canal was built in the 1920s to create land for Waikiki development. Waikiki is at risk if the canal overflows.

The state and the Army spent about $5 million each on feasibility studies for the project, which is only about 35 percent into the design phase. So far, the the corps is proposing to put a 4-foot-tall concrete wall around the canal and place six in-stream debris and detention basins in the upper reaches of the watershed that flows into Waikiki. The project also includes pump stations, a stand-alone debris catchment and three multipurpose detention areas in open spaces throughout the watershed.

Congress already has appropriated $345 million in emergency funds, which don’t expire but could be re-appropriated at the discretion of Congress and the assistant secretary of the Army for civil works. Gov. David Ige’s budget seeks $125 million to meet a federal cost-share requirement. But it’s unclear whether state lawmakers will approve Ige’s request and, even if they did, whether the project would move forward since it still lacks a nonfederal partner.

Next the bill must go before the full state Senate. If it clears that vote, it would cross over to the House, where it could get a frostier reception. House Finance Committee Chairwoman Sylvia Luke has previously said the Ala Wai flood control project is a Hono­lulu city works project.

The Army also needs the state, the city or both entities to agree to become project signatories. City and state officials told lawmakers Tuesday that they are negotiating but so far have not reached agreement.

Ways and Means Chairman Donovan Dela Cruz said his committee added a new section to the bill that requires the city to enter into a partnership with the Army Corps of Engineers and “accept all the project features identified in the Ala Wai Flood Risk management project upon completion.”

Because state funds are limited, Dela Cruz said the committee report also would reflect that the state may use a portion of the city’s share of Honolulu’s Transient Accommodations Tax for a 30-year payment option.

The committee, which wasn’t unanimous in its approval of the bill, also changed the effective date to provide more time for discussion to 2050. So far, three neighborhood boards — Manoa; Diamond Head, Kapahulu, St. Louis Heights; and Makiki, lower Punchbowl and Tantalus — have passed resolutions asking state lawmakers to put the project on hold until communities can provide more feedback. Residents and schools on or near the project’s sites also have objected.

Sen. Brian Taniguchi (D, Manoa-Makiki-Punchbowl) cast the sole “no” vote on the bill.

“I respect the work that the corps does and respect that we have to be concerned about Waikiki, but felt that the way that they handled this was not right. The people upstream are paying for it without any real benefit,” Taniguchi said after the hearing. “I had the sense that there wouldn’t be that much flexibility in terms of changing plans.”

Several senators passed the measure with reservations, including Sharon Moriwaki (D, Waikiki-Ala Moana-Kakaako), Maile Shimabukuro (D, Kalaeloa­-Honokai Hale-Ko Olina­-Nanakuli) and Kurt Fevalla (R, Ewa Beach-Ocean Pointe-Iroquois Point).