“We can do it. We must do it. Hawai`i has set an example for the nation with our energy policies,” he said. “We should also replicate it [and] become an example for the stewardship for our water resources.”
Schatz, as chair of the Senate’s water and power subcommittee, said he convened the forum to hear a variety of local perspectives on water supply issues and to learn more about the impacts climate change will have in Hawai`i. Together with a similar panel discussion at the Hawai`i Conservation Conference, also held in August, it seems that resource managers at the state level and on O`ahu, at least, are well aware of the potential impacts climate change will have on supply and are working to mitigate them.
“We keep thinking that future end game, that black swan … is not going to happen to us,” said state Commission on Water Resource Management director William Tam, who spoke at both events. “We have to rethink how we live here.”
Mauka to Makai
Data indicating that climate change has caused drops in rainfall and stream flow throughout Hawai`i have been available for some time. For state Department of Land and Natural Resources director William Aila, the impacts of climate change became personal only recently.
“This past Thursday, coming back from a cabinet meeting in Kona, I arrived home to about seven fire trucks in my yard,” battling a fire in what used to be a sugar plantation reservoir. Aila blamed the changing weather patterns.
“We used to have regular summer rains. There have not been any summer rains for the last 10, 15 years,” said Aila, a lifelong resident of Wai`anae on O`ahu’s leeward coast. “The brown time seems to be expanding. We used to get rains all the way through May. Now, it’s to February or March. Rains used to rain out Halloween. We don’t get rains ‘till Thanksgiving now,” he said. “This entire reservoir was reduced to grass, brown grass, that burned hotly and intensely for eight hours.”
For more than a year now, with its Rain Follows the Forest campaign aiming to double the amount of protect forest areas over the next decade, Aila’s department has been a forerunner in the state’s effort to combat the impacts climate change is expected to have on the state’s water supplies and ecosystems.
Aila said that when he started his job as head of the DLNR, he quickly began to receive briefings from scientists about the future being drier and bringing more intense storms to the islands.
“Now that you know about it, you can’t ignore it. … A good forest acts as a sponge” that benefits not only the state’s aquifers, but its marine organisms as well, he said.
“We have a very strong mauka to makai relationship,” he continued, noting that pelagic fish rely on a certain amount of larval fish from coral reef ecosystems for food. And those larval fish rely on freshwater discharges into the ocean.
This past legislative session, the Rain Follows the Forest program received appropriations totaling $11 million over two years.
When discussing ways to ensure the state has adequate water for agriculture, Aila hinted at a rift in his department over implementation of dam safety rules adopted by the Land Board years ago in response to the Kaloko reservoir breach on Kaua`i that killed seven people. The rules potentially require dam and reservoir owners to make expensive improvements
“Carty pulls his hair out whenever I talk about dams,” Aila said, referring to Carty Chang, head of the DLNR’s engineering division, charged with overseeing dam safety and implementing the rules.
“If we are to become more self sufficient, we need to store more water,” Aila said, adding that he is looking at ways to manage dams and reservoirs “in a more flexible way than our engineers had envisioned.”
Draining dams may be good from a safety standpoint, but it’s not good for agriculture, he said.
‘Reduce, Reuse, Recycle’
Climate change is definitely putting the Honolulu Board of Water Supply in a pinch. If the steady decrease in rainfall over the past few decades is factored into the sustainable yield for the island, pumpage is already at capacity, said the BWS’ Barry Usagawa at the Hawai`i Conservation Conference. Currently, the permitted capacity is 294 mgd. On an average day, only about 180 mgd is used.
The BWS currently serves nearly 1 million people, a number that is expected to grow to 1.1 million by 2030. Under the current sustainable yield of 407 mgd, there is still ample capacity to grow, Usagawa said.
“By 2030, we should be okay. What happens if the sustainable starts to decrease because of lower rainfall, when the wells are too concentrated [and] pull up brackish water? We’re always constantly looking at that,” he said.
The agency hopes to control development so it doesn’t damage the ability of the island’s aquifers to recharge, said BWS engineer Ernie Lau at Schatz’s forum. In addition, Usagawa said, the BWS has developed a policy to minimize production of new water sources on the island’s windward side because tapping the high-level dikes there would impact streams.
To protect traditional and customary practices, the BWS has adopted a policy not to develop any new sources that affect surface water, Usagawa said.
To help preserve the island’s overall water supply, the BWS has recently entered into agreements with the DLNR to fund the protection of forested recharge areas and control invasive species, among other things.
Usagawa said he was embarrassed when he found out Maui County donates $2 million annually to watershed partnerships. Until recently, O`ahu had only donated about $20,000 a year to partnerships with the DLNR.
The BWS has also been investigating ways to improve conservation and develop alternative water supplies, including recycled/brackish water and desalinization.
Tam has frequently touted the idea of recycling the wastewater that feeds the city’s treatment plants at Sand Island and Honouliuli.
“At Sand Island, 60 million gallons of wastewater goes into the ocean. At Honouliuli, it’s 20 to 30 million gallons. [That’s an] asset we’re throwing away,” Tam said at the HCC.
The BWS currently recycles eight to ten mgd of wastewater at the Honouliuli wastewater treatment plant and is “very interested in expanding as the plant goes to secondary treatment,” said Lau at the state Capitol forum.
The City and County of Honolulu has not yet needed to develop a desalination plant because of the success of its conservation programs, Usagawa said. (One was built in the early 1990s, in a three-way partnership involving the BWS, the DLNR, and the Campbell Estate. The $8 million plant never worked well and was later abandoned.)
When asked about ways to expand the use of recycled water on O`ahu, Usagawa said the technology exists to do small-scale, on-site recycling, but “we lack the leadership.”
The need for recycled water is also there, he continued, pointing to the municipal Ala Wai golf course as an example.
“A sewer transmission main goes through [the property]. The caprock wells are salty, [so] they’re using potable water. They can use recycled water,” he said. But it takes three county departments to come together to make it happen: the Department of Enterprise Services, the Department of Environmental Services, and the BWS, he said, adding that if they ever find a way to make it happen, it would save 250,000 gallons of potable water a day.
“The University of Hawai`i College of Engineering came up with conceptual designs. I can’t get it moving forward,” he complained.
Effluent-cleaning facilities could produce irrigation water for golf courses in Makaha, and for landscaping in Mililani if the Koa Ridge development ever gets built, he said.
The city’s Wahiawa wastewater treatment plant is expected to soon produce high-quality recycled water, which farmers will use, he added.
Stream Gages
At Schatz’s forum, one glaring weakness in the state’s effort to deal with climate change stood out: the loss of U.S. Geological Survey long-term stream gages.
In the 1970s, the agency operated 200 stream gages across the state. But due to a lack of funding, today, there are only 58, reported Stephen Anthony, director for the USGS Pacific Island Water Science Center.
“We need good data. We are losing gaging and rainfall stations. … That’s the early warning system. That’s the canary in the mine,” Tam lamented.
University of Hawai`i coastal geologist Chip Fletcher added that monitoring streams at a time when rainfall is decreasing, “that’s a period where we need to know much more.”
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