Locating a site for a new Oahu landfill became a more — not less — urgent problem with the city’s announcement just over a week ago that it would seek a two-year extension to keep the Waimanalo Gulch landfill near Kapolei open.

Late last year, the city’s Landfill Advisory Committee, charged with finding a new site in place of Waimanalo Gulch, voted not to recommend any of six proposed locations. That decision seemed to push the city to once again make Waimanalo Gulch in West Oahu the fallback.

After repeated, failed attempts by the city to find another suitable location on Oahu, however, residents’ patience is wearing thin — and the cumulative effect of continued Waimanalo Gulch operations on those living nearby is approaching a point of no return.

Mayor Rick Blangiardi has pledged to work diligently to find an alternative, and close the West Side site. Community residents, environmentalists and all of Oahu, which depends on the current landfill to take our garbage, will be watching closely to see what comes next, and for reassurance that the city administration is not merely paying lip service to a search for alternatives.

The city’s request for an extension comes under pressure from a 2019 state Land Use Commission (LUC) order that the landfill be closed by 2028. However, in 2020, Hawaii’s Act 73 placed new restrictions on potential landfill sites, banning placement in conservation zones or near housing. That left Honolulu with limited options.

Six locations were identified by the city — but the Honolulu Board of Water Supply (BWS) rejected them all. Each is located over the island’s aquifer system or in a “No Pass Zone,” believed vulnerable to groundwater contamination that could jeopardize Oahu’s drinking water supply.

BWS holds that no measures can completely isolate Oahu’s water supply from contamination if a landfill is placed in a vulnerable location. The Red Hill leaks have emphatically, catastrophically, brought this message home, and it’s likely that most residents of Oahu would prefer not to endanger its sole source of drinking water.

That leaves a couple of other options. One is looking at military property. The other is taking a hard look at the Act 73 restrictions that leave so little land on Oahu available to consider.

There is already one military landfill on Oahu, at Kaneohe Marine Corps Base Hawaii. That raises the possibility that other military property is suitable on Oahu, and this could present an attractive option, particularly if it does not require loosening other restrictions.

Given the Navy’s disaster at Red Hill — where fuel and toxic firefighting foam have both spilled more than once, threatening the island’s water supply and requiring extensive, expensive remediation — it’s justifiable to expect that the military should step up to aid Oahu in siting a new landfill in the safest, most suitable location possible.

More must be known about suitability on military lands, but the U.S. Department of Defense, along with Hawaii’s federal, state and city representatives, should immediately launch a good-faith exploration into the possibilities.

Other options for a landfill outside of the BWS’ No Pass Zone would require a change in the restrictions imposed by Act 73. Roger Babcock, director of Honolulu’s Environmental Services Department, has suggested that an exception could be sought to allow a landfill on property currently zoned for conservation. This option, too, must be fully explored.

Should the LUC agree to extending the search for a replacement to Waimanalo Gulch, the city must take this as an ironclad commitment to be out of the West Side as soon as a new location can be prepared, and as close to 2028 as possible.