People on Oahu will soon have a much easier way to know if they live, work, or visit an area at risk from dams and breaches.

It’s an issue KHON2 and Always Investigating have been following since last week’s Nuuanu Reservoir scare.

After heavy rains from Tropical Storm Olivia, the Board of Water Supply was quickly pumping water to reduce the levels at Nuuanu Reservoir #1. The BWS said 10,000 residents could have to evacuate if the situation didn’t improve.

It turns out many of those residents didn’t know they were at risk, and we wanted to know the plans for other communities in similar situations.

Always Investigating found very little public knowledge about what to do and who would have been affected not just in Nuuanu, but near the more than 130 other regulated dams statewide.

Honolulu County is being the most proactive in making quick changes, and state lawmakers want to see such action elsewhere too.

Before last Thursday’s scare in Nuuanu, concerns about dams and the areas of potential evacuation have not been included in broad disaster readiness messaging.

“Frankly for this particular one, not too many folks were aware,” said Mel Kaku, director of the Honolulu Department of Emergency Management.

Always Investigating researched the largest reservoirs on every island, and we asked each of those dam owners — public and private — to share the evacuation maps from the emergency action plans (EAPs) that state law requires they make.

Click here for a list of Hawaii’s largest regulated dams.

Honolulu County provided all of their county-controlled plans. That includes the much larger Nuuanu Reservoir #4, and the even bigger Kaneohe dam, plus another in Waianae. Click to view:

The private owner of the biggest in Hawaii — the Wahiawa dam — didn’t want the whole EAP shared, but we found the evacuation map portion within an 800-page county emergency plan from 2007.

The largest private dam owners on the neighbor islands, including Kaloko where a deadly 2006 flood happened, have not given us anything yet.

Maui County shared their big county dam’s evacuation map for the Piiholo reservoir.

But Hawaii County and several state departments that own Big Island and Kauai dams resisted, some stating security, confidentiality and not wanting to scare residents as among their reasons to withhold.

“It doesn’t create the right perception as well as the right response in the event we do last-minute notifications,” Kaku said. “It’s better to share that information to the extent possible.”

“I think the last thing we should be worried about is scaring people, we have to remember what happened in the Kaloko situation on Kauai. Several people died as a result of that dam breach,” Rep. Sylvia Luke said.

DLNR has 132 of these maps on file but declined to share them, telling Always Investigating in a statement: “The DLNR Engineering Division considers Emergency Action Plans sensitive documents that have the potential to pose a security issue and frustrate emergency activities, including evacuations and remediation activities.”

Lawmakers want to change that.

“Those things all need to be public,” Luke said. “If there is a future breach, what are they going to do?”

Always Investigating asked what lawmakers intend to do about it.

“We are going to be meeting, having several meetings…to ensure that there’s better communication and more information to the public,” Luke said.

The DLNR points out that people can plug in an address to a mapping website to see if they live in a flood zone. DLNR says it “will be proceeding with discussions with the respective County Emergency Management Agencies on how to better advise the public on their risks for dam failures and the evacuation areas for these risks.”

All county emergency management agencies internally have maps and plans in place, even templates for warning messages. While rainwater rise can be averted with drainage ahead of the storm or pumping during and after, a major break such as from an earthquake would rush millions of gallons of floodwater through some good-size towns within minutes.

Always Investigating asked, what are some ways emergency officials can achieve outreach to those areas instantly?

“One of the notification features that we have planned for is use of sirens in that particular general location,” Kaku said. “We feel if we have sufficient time, we’ll go door to door, which is the 100-percent method of confirmation.”

In the April storm that flooded Kauai, police and firefighters went door to door to evacuate about 20 homes near Kalihiwai dam.

As for reaching out by mobile phone and mobile alert in a geographic area, Honolulu DEM is close to being able to do that.

“We are planning to implement something similar to that, rather than do island-wide,” Kaku said, “especially for a specific hazard. The idea is to identify a polygon area and the idea is if you’re passing through for that individual to be able to get the that notification.”

Meanwhile, Honolulu County’s DEM director says they’re meeting as early as next week on how to get even more maps up for the public to see.

We’ll follow up on any next steps to make evacuation plans more transparent statewide.