Waihe’e Aquifer Fact Sheet

FACT: Waihe’e aquifer water is some of the best quality water on Maui

FACT: Few families living beyond the Waihe’e river (Kahakuloa side) have any access to a public water source.

WHERE IS WAIHE’E AQUIFER?

• Waihe’e aquifer extends from Waihe’e stream to Kahakuloa, an area of around 12 square miles. 

WHAT IS ITS CAPACITY?

• Scientists once estimated Waihe’e could produce 8 million gallons of water a day. All the county wells are concentrated in only one section of the aquifer.
• Hydrologist John Mink suggested a limit of 4 million gallons per day (mgd) of pumping use by county wells, because they did not span the whole aquifer.
• More scientific studies suggested that 8 mgd was too high to be a realistic expectation for the whole aquifer, due to geological conditions.

WHO USES WAIHE’E AQUIFER?

• Maui County currently reports 4 wells pumping from Waihe’e aquifer.
• An additional well is drilled, but used for aquifer monitoring.
• The County’s North Waihe’e well field lies between Waihe’e stream and the Boy Scout Camp at Maluhia .
• County well sites were purchased from C. Brewer/ Wailuku Ag around 15 years ago.

HOW MUCH WATER DO WAIHE’E WELLS ALREADY PUMP?

• The North Waihe’e Well Field wells average 3.63 million gallons of use each day (2011).
• Five years ago use was at 4.6 mgd (2005-06)
• Each well currently pumps a little less than 1 mgd
• The combined pump capacity of the wells is 6 mgd

WHY ARE WAIHE’E WELLS IMPORTANT?

• Waihe’e wells relieve use on the Iao aquifer, although both aquifers are connected.
• Waihe’e Wells serve central and south Maui residents through the Central Maui system
• Waihe’e wells are at moderate elevations, which means moderate pumping costs and its waters have no reported agricultural contaminants
• The four Waihe’e wells produce 40% more clean water (3.6 to 4 mgd) than the 9 wells in the County’s Lahaina water system (2.4 mgd)

WHO ELSE WANTS TO USE WAIHE’E AQUIFER?

• North Waihe’e wells are located on TMK 3-2-01: port 3,
• This 369 ac parcel, formerly owned by Betsill Brothers, is in foreclosure.
• Two Betsill Wells, drilled in 2004, are on the same parcel and are proposed for a commercial water bottling plant.
• The wells are each permitted to pump up to 220,000 gallons per day
  
• Several other private wells exist in Waihe’e aquifer, towards Kahakuloa.

HOW IS WAIHE’E AQUIFER MANAGED?

• In 2002 ‘Iao and Waihe’e aquifers were proposed for “designation as state water management areas.” This means the state Commission on Water Resource Management (CWRM) would carefully manage any permitted withdrawals to keep aquifers healthy.
• 1n 2002 a “trigger” was set for Iao aquifer: use averaging over 18 mgd
• Iao aquifer reached its trigger point in July 2003, and was designated.
• Waihe’e aquifer also had a “trigger,” based on a 1 foot decline in water level in one North Waihe’e well.
• In 2004 the trigger level for Waihe’e aquifer was removed, but the CWRM and Maui County agreed on a MAXIMUM pumping level of 4 mgd from the North Waihe’e wells, averaged over one year.

HOW MUCH MORE WATER CAN BE SAFELY PUMPED FROM WAIHE’E AQUIFER?

• County wells currently withdraw what is considered a safe pumping level from Waihe’e aquifer yet some months pumping still exceeds the 4 mgd limit.
• Higher pumping can result in well water levels beginning to drop over time
• CWRM staff recently stated, “water levels in the Waihe’e aquifer are already close to triggering designation for state management, and additional pumping could bring it closer to that point.”

 

WHY DID THE WATER COMMISSION PERMIT THE 2 BETSILL BROTHERS WELLS?

• The Commission issued two well permits to “Ko’olau Cattle Co.” in 2004 for Waihe’e wells: one well for domestic use at .220 mgd capacity and one well for irrigation at .24 mgd capacity.
• CWRM staff expected modest use from the wells for many years as 24 subdivision lots were gradually sold and residences developed. 
• Irrigation wells were expected to help recharge the aquifer. Domestic use also would offer some recharge.
• No mention was made of a commercial water bottling plant that would use half or more of the aquifer’s remaining legal capacity and send the water off-site

WHAT HAPPENS NEXT?

• Maui County Planning Director Will Spence said he believed the Maui Planning Commission would need to approve a special use permit in order for a water-bottling operation to be constructed on the property, which is in an agricultural zone.
• CWRM staff stated that the wells would need to be re-permitted for the proposed commercial use. Other well or stream users could object.
• Regular pumping by a bottling plant could cause the aquifer to exceed its safe capacity and be designated as a water management area, or force the county wells to cut back use.
• Department of Land and Natural Resources Chair William Aila said the county could adopt a policy stating that the remaining capacity of Waihe’e aquifer should be used for the public system.
• 200,000 gal a day would allow water permits to be issued for 300 affordable homes and a new school.

 

 

BOTTOM LINE: Should kuleana users and public water systems be given preference over for-profit commercial interests or vice versa?

Let county officials know what you think is the highest and best use of this resource.