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State water management officials fear some aquifers in West Maui might be showing signs they are surpassing their sustainable yield in pumping water, raising questions about water allocations for future developments.

Officials with the state Commission on Water Resource Management say they’re starting to notice salinity levels in Napili and Kaanapali rising in certain instances with more pumping.

Based on the studies, it could be an indicator that the quantity being pumped might not be sustainable, officials said.

In the last 20 years, West Maui has received less rainfall, and the department is tracking the situation. At Honokohau Stream, the mean daily flow has decreased by 11.5% in the last 20 years, according to the study.

Less rainfall means reduced runoff and reduced recharge to the aquifers.

The Lahaina aquifer is comprised of six aquifers, including Honokohau, Honolua, Honokowai, Launiupoko, Olowalu and Ukumehame.

There is a monitoring well at Mahinahina, and state officials said plans are to have a monitoring well farther south at Launiupoko, where there appears to be a potential for more groundwater.

According to state officials, about 1.2 million gallons a day of groundwater is pumped daily from Launiupoko, which has an estimated sustainable yield of 7 million gallons daily.

The department said that since the Commission on Water Resource Management has designated ground and surface water under its jurisdiction in West Maui, state commission permits will be required for some developments.

A meeting about the permit procedures is set for at 9:30 p.m. April 28 at the Lahaina Civic Center.

A meeting at Lahainaluna High School was held April 7 as a preview to the meeting later this month.