If you own or are considering buying property in Maui containing cesspools, staying informed is important. Sewage management is a serious problem in Hawai’i, and these 88,000 cesspools pose a real, immediate concern. Several state laws have been enacted recently, with a new bill under consideration. As Maui residents ourselves, the Maui Property team has looked into this potentially daunting subject multiple times. In particular, the Upcountry areas of Maui contain a lot of cesspools, while the Wahikuli neighborhood north of Lahaina is known to have them as well. In my experience of purchasing property in the area, this issue deserves thorough research. Here is a summary of the Hawaii Cesspool Laws of recent years:

2016's Act 120 banned the construction of new cesspools. It offered $10,000 tax breaks for converting a qualified cesspool to a septic tank system, an aerobic treatment unit system, or connecting to a sewer system. This incentive was good until the end of 2020.
In 2017, Act 125 required upgrading all existing cesspools by 2050, and the state Department of Health was asked to develop a method for determining which areas should be prioritized first.
2018's Act 132 set up the Cesspool Conversion Working group to create a comprehensive plan for cesspool conversion, consisting of government and industry partners, including Hawai‘i REALTORS®. The cesspool conversion working group was created to generate a detailed, statewide conversion strategy for all cesspools to be accomplished by 2050. The objectives outlined for this group include providing interim reports and their suggested recommendations to the legislature on or before December 31st, 2020, and 2021. In addition, a final report, along with any proposed legislation, must be handed to the legislature no later than twenty days before the start of the 2023 legislative session.
In 2021, a new bill titled SB369 SD1 was introduced that calls for the Department of Health to inspect and repair any individual wastewater system at the time of sale or transfer of residential real property connected to it, excluding certain sales or transfers. It also removed the limitation on types of wastewater systems to which cesspools must be upgraded or converted and requires it to be done before January 1, 2050. Testimonies were submitted both in favor and against the bill, and the full testimonies can be found online.
Data from the 2009 and 2014 University of Hawai‘i, Department of Health and Environmental Protection Agency joint effort shows estimates of the number of cesspools by island and their total discharge. This estimate was compared to housing data from the same year's census. This is important to know when buying or selling properties with cesspools on Maui.
For Specific Questions about Cesspools on Maui contact:
Phone: (808) 586-4294
Fax: (808) 586-4300
Wastewater Branch
Environmental Management Division
Hawaii State Department of Health
Hale Ole Building
2827 Waimano Home Road, Room 207
Pearl City, Hawaii 96782