The impending threat of sea-level rise from climate change has prompted the Honolulu City Council to consider increasing shoreline setbacks to push development away from vulnerable coastal areas.

A proposed measure, Bill 41, would increase the general 40-foot shoreline setback to between 60 and 130 feet, depending on the location and size of the property. It is just one step the Council is examining to move in the direction of “managed retreat” from the coastal shoreline.

Chip Fletcher, director of the University of Hawaii Climate Resilience Collaborative, and his team have been studying annual coastal erosion rates around Oahu for decades. He said the type of setbacks the Council is considering in Bill 41 would be particularly useful because they would be applied on a sliding scale based on local conditions and not a flat rate for all properties.

Bill 41 sets a base shoreline setback for new development of 60 feet but adds increases of 70 times the annual coastal erosion rate, up to a maximum 130-foot setback.

For example, if the annual coastal erosion rate for a beach is 0.5 foot, the shoreline setback for the property would be 60 feet plus 35 feet — or 0.5 multiplied by 70 — for a total of 95 feet.

However, under Bill 41, urban Honolulu from Pearl Harbor to Kahala would be subject to only a uniform 60-foot setback.

Council member Esther Kiaaina said she wants to make sure that discussions on how to move communities away from retreating shorelines start now.

“For public discourse, it’s healthy for all of us to realize we may not have the solutions, and of course the government wouldn’t be able to afford to compensate people or relocate everybody, but we have to have that dialogue,” she said.

“As it pertains to coastal erosion, the magnitude is going to be big, and is Hawaii ready for it? I don’t believe we are because we’re not even talking about it. I’m not professing to know the answer, but to not have the dialogue, I think, is unhealthy.”

She said the city should at least adjust property tax valuation to reflect a decrease in value due to the portions of land that would be affected by the increased setbacks.

Naalehu Anthony’s family has been on its shoreline property in Kaaawa since around 1978. He is concerned about the families who have held onto coastal properties for years, hoping to pass their land down to their children.

“When you start to think about some of these rules that could be in place, we’re really talking about what happens to generational wealth-building in some of these families that could be eviscerated,” he said.

“It’s not to say that we shouldn’t be having a conversation about climate change … but we also want to look at the challenges and not just say, ‘We need a setback, we can’t build anymore,’ because that’s going to change the fabric of how wealth is built here, and it may adversely impact those of us that have just been really trying to hang onto what’s left.”

One of the ways the city Department of Planning and Permitting is trying to incentivize people to move away from the shoreline is by a “transfer of development,” which is proposed in Council Bill 10, for properties in special management areas, namely those areas near the ocean.

If that measure were to pass, the city would begin identifying properties most affected by the next 6 feet of sea level rise and then find comparable parcels more inland. The city would then allow the property owners to relocate to the more inland parcel but retain the same zoning rights as on their coastal property in order to establish themselves on the new site.

DPP Director Dean Uchida said the department is still working out the details, such as whether the city should trade owners of coastal property for new property elsewhere, or if there would be some type of costs to property owners, since the city would likely need to install infrastructure to serve the new lots.

“The transfer development rates would be used for somewhere along the coastline. If they have a house, maybe they can transfer to an area we identify for residential, and they can take whatever the zoning is on the lot along the coast and move it up to the place to relocate,” Uchida said.

“That’s the concept we’re talking about, and transfer of development right in (Bill 10) would give us that tool, the flexibility to do it on a going-forward basis.”

However, especially for families who have lived in their coastal homes for generations, the answer is just not as simple as relocating.

Kealoha Domingo, who owns coastal land in Koolauloa on the North Shore, said family properties are meant to be cared for and passed down.

“It’s not a commodity that I want my value to be elevated so that I can sell it for a profit. I want it to be there for my family and for my kids for generations to come,” he said.

Domingo said his family is one of the longest-standing in the area, and his property has a family burial on it.

“That’s an even deeper connection. We’ve been there for generations, and we have the bones and the headstones to prove it,” he said. “So that’s just a responsibility that goes beyond any law that you can recite to me. …

“But on the scientific side of it, sea level rise is a real thing — I know that. It’s unfortunately somewhat inevitable.”

Fletcher explained that managed retreat and mitigation plans for both rural coastal zones and urban Honolulu need to be established in this decade, as over time, flooding, land loss and an increase in so-called king tides, the highest tides of the year, continue as precursors to the imminent impacts of climate change.

However, he emphasized that the community needs to be driving the strategies to avoid perpetuating the history of land-taking in the state.

Anthony agreed that communities need to be heard during the decision-making process.

“I don’t want to fight and deny climate change. I want to fight for solutions for these communities. I want to figure out how it is that we buy time, how it is that we modify our behavior, how it is that we can make changes together to figure some of this out,” he said.

“I think that there are solutions out there. They’re going to be expensive; not all of them are going to work. We’re going to have to try really hard. Our communities are going to have to work together, but that’s what island communities have been doing for centuries.”

The Council is expected to discuss and vote on Bill 41 for second reading Wednesday.