There’s not enough for all projects planned, proposed; viability of cloud forest a worry
By ILIMA LOOMIS, Staff Writer
WAILUKU – Building out all the developments that have already been planned or proposed on Lanai would result in more water being pumped out of the island’s wells than could be sustained, according to the county’s draft Lanai Water Use and Development Plan.
The plan also finds that as much as 28 percent of the water pumped on the island is unaccounted-for due to loss or waste in the system, and that the island’s watershed is so fragile that a loss of the Lanaihale cloud forest could reduce water levels in the island’s only viable aquifer by 50 percent.
The findings and recommendations of the water plan will be discussed at a meeting of the county’s Board of Water Supply on Lanai on Wednesday. The meeting will be from 5 to 8 p.m. at the Lanai High and Elementary School.
Lanai’s water system is owned and operated by Castle & Cooke Resorts. According to the report, hydrologists estimate the total sustainable yield of the island’s aquifers, or the amount that could be drawn without damaging the aquifers’ viability, is 6 million gallons of water per day. Total withdrawals in 2008 were about 2.2 million gallons per day, according to the report.
But the report notes that a 2009 Castle & Cooke development proposal estimates that total demand for water would be almost 7 million gallons per day if all the projects were built out. That proposal plans for 1.5 million gallons per day that would come from “alternative sources” that are not specified, the report notes.
While project districts at Manele and Koele were approved in 1986, only a small fraction of the hotel and housing units approved in those plans has been constructed, leaving hundreds more units that are unbuilt but fully approved, the report notes.
The Lanai Water Use and Development plan draft also notes that a significant amount of the water already being pumped on the island appears to be lost due to waste. Islandwide, 28.3 percent of the pumped water is unaccounted-for.
The report also estimates that 485,000 gallons per day could be saved through “reasonably achievable conservation.” That number includes an estimated 200,000 gallons per day that could be conserved by repairing the leaky Palawai Grid, 111,000 gallons per day that could be saved on landscaping with more efficient irrigation, and 100,000 gallons that could be saved by replacing fixtures.
The report also raises serious concerns about the loss of forest on Lanaihale. With little rainfall and no known natural surface water sources, more than 65 percent of the water that recharges the island’s primary aquifer is believed to come from fog that accumulates on the leaves of forest trees and drips onto the ground.
But the cloud forest has been declining, due to grazing animals and invasive plants, according to the report.
“Loss of fog drip from Lanaihale would lead to the loss of over 50 percent of the water levels in the central aquifer, essentially the only viable water source for the island,” according to the report.
The draft plan includes recommendations for “aggressive forest conservation measures,” including fencing and ungulate removal. It also recommends allocating water for future build-out of development, not allowing unidentified sources to be included in water allocation, and taking steps to reduce water consumption and unaccounted-for water in the system.
It also said new projects should be allowed only in exchange for already-approved units, not in addition to them, and that prior approvals should be voided if fencing and other watershed protection efforts fail to make progress.
The draft plan can be viewed online at www.co.maui.hi.us/index.aspx?nid=1617, or copies are available at county Department of Water Supply offices in Wailuku or at the Lanai Public Library.