The Honolulu Board of Water Supply is moving forward with a plan to demolish the Haiku Stairs, although both supporters and opponents of the plan insist the fate of the popular — but now illegal — hiking trail is far from decided.

The board Sunday issued a formal notice that it is preparing an environmental impact statement that puts forward removal of the stairs as its “proposed action,” as well as three alternative plans that would keep what’s been dubbed “the Stairway to Heaven” in place.

Board officials have made it clear that keeping the stairs open and maintaining them are beyond the scope of their mandate to deliver a safe and reliable water supply to Oahu residents.

Water Manager Ernest Lau said in a statement Monday, “Managing Haiku Stairs draws BWS staff, financial, and other resources away from our core mission to efficiently and effectively meet the water demand of our customers.”

However, “although the BWS’s preference is to remove or transfer the stairs to a government agency to protect the public and eliminate liability to BWS and to our rate payers, it is also important to be open and listen to what the community has to say about these alternatives,” Lau said.

The 3,922-step “stairway” was created by the Navy in the early 1940s so personnel could reach communications equipment in the upper valley. It was also open to the public as a recreational resource, but it was shut down to the public in 1987 due to vandalism and liability concerns.

But hikers continue to flock there at the risk of being cited for trespassing, an offense that would require a court appearance and possible fines of up to $1,000, community service and possibly six months in jail.

The stairs’ popularity has also spurred a multitude of complaints from Haiku Valley residents who say hikers trespass onto their property, trash their neighborhoods and get into confrontations with them.

Public comments on the options are being sought, and are due to the Office of Environmental and Quality Control by May 23.

The nonprofit Friends of Haiku Stairs, which for years has fought to legitimize access to the trail, is urging the public to submit testimony highlighting the area’s significance and need for it be open.

Vernon Ansdell, Friends of Haiku Stairs president, said there remains significant support for keeping the trail open both locally and internationally. “Hopefully, we can convince (decision-makers) that it just makes no sense whatsoever to spend all this money to remove the stairs and destroy this world-class attraction,” he said.

“It’s fabulous up there. … It’s almost a spiritual experience once you get up there near the summit,” Ansdell said.

His group has come up with a financial plan that would allow the entire upper valley to be maintained as a park through a public-private partnership that would focus on educating people about the area’s natural and cultural resources, Ansdell said.

Assessing a fee would cover liability insurance and proper security, and reopening legal access would shift hikers away from the illegal entrance points and the area’s neighborhoods, he said. Such a plan would also allow for managing how many people are on the trail at a time. The group does not want the area turned into a theme park, he said.

Area City Councilman Ikaika Anderson said he would prefer that the community work together on a plan that would allow limited and controlled access while taking care of the neighbors’ issues.

But when he convened a public-private task force in 2014 to see whether stakeholders could come to a mutual agreement, BWS officials made it clear they would only consider transferring ownership of the land to another government agency because of liability issues.

At this point “it is obvious that no governmental entity will step forward anytime soon,” Anderson said. “As such, unfortunately, it is time to remove the stairs.”

As the issue has festered, area residents have been “verbally assailed and physically attacked on their own properties by trespassing hikers,” he said. “We cannot have the health and safety of our residents compromised.”

Ansdell said he’s seen little effort by BWS to find willing collaborators. “We’ve got different inquiries from different groups,” he said.

The board insists the tearing down of the stairs is not a certainty.

“The BWS is committed to evaluating each alternative thoroughly and providing an accessible process for public comment through small-group and public meetings with various agencies, landowners, community organizations and individuals with an interest in this project,” Lau said.

The EIS process is expected to take about a year, BWS spokeswoman Kathleen Pahinui said.