Imagine Clean Water for Generations to Come

Imagine flushing your toilet directly into the ground, just inches from our pristine groundwater and coastal resources. That is the current reality for thousands of Hawaiʻi island residents who rely on outdated cesspools. These aging systems pose risks to public health, drinking water quality, and our fragile coral reef ecosystems.

ACT 125: Hawaiʻi’s Cesspool Mandate

In 2017, the Hawai‘i State Legislature passed Act 125, requiring the elimination and replacement of all cesspools statewide by 2050. The Hawai‘i Department of Health (DOH) was tasked with prioritizing replacements based on risk to public health and the environment. In 2022, Act 87 (SLH 2022) expanded compliance options to include system upgrades, conversions, or connections to municipal infrastructure.

To support our community through this transition, the County of Hawai‘i Department of Environmental Management (DEM) developed the Cesspool Conversion Evaluation Report.

Is My Cesspool on the Map?

The University of Hawaiʻi Water Resources Research Center is updating the statewide inventory of existing cesspools and needs community input. Because historic records are limited, local knowledge is critical to improving accuracy.

If you spot an error on the map—such as a listed cesspool that doesn't exist, or an unlisted cesspool that does—please let us know:

• Explore the Map: Visit the UH Wastewater Mapping Tool.

• Submit Corrections: Email details, descriptions, or spatial data/shapefiles to infowrrc@hawaii.edu.

Understanding the Cesspool Conversion Evaluation Report

The Cesspool Conversion Evaluation Report serves as a technical evaluation and for County leadership and policymakers. It is part of the County's Integrated Wastewater Management Plan, which is a comprehensive review of the County’s wastewater infrastructure and a long-term effort to protect public health and the environment, improve the reliability of aging systems, and plan for future improvements.

Scope of the Cesspool Conversion Evaluation Report

• Evaluating Existing Sewer Networks: Identifies potential opportunities where existing municipal treatment facilities could extend sewer service.

• Exploring Decentralized Solutions: Identifies candidate communities where shared wastewater systems could be constructed if external capital and operational funding are secured and where private partnerships can be formed.

• Individual Wastewater System (IWS) Upgrades: Outlines guidance for rural and remote areas where private, on-site upgrades (such as septic or aerobic systems) remain the primary long-term solution.

⚠️Important Note on Scope & Funding:

The Cesspool Conversion Evaluation Report is an analytical tool—it is not an active capital implimentation plan or a funded municipal project. The Department of Environmental Management provides this technical analysis to assist the County and public partners in evaluating options.

Project implementation, infrastructure construction, and sewer extensions are contingent upon securing funding, including state/federal grants, legislative appropriations, Sewer Improvement Districts, and Community Facilities Districts. Under State law, private landowners are ultimately responsible for maintaining compliant wastewater systems on their properties.

Timeline & Public Engagement

Regulatory Enforcement & Permitting

BE A PART OF THE SOLUTION

📆Attend Public Meetings

• Join our upcoming public sessions to review findings and discuss potential community solutions:
  1. Environmental Management Commission Meeting 
     • August 26th @ 9AM
     •  Via Zoom https://www.zoomgov.com/j/1612028078
     • Meeting ID: 161 202 8078
     • PHONE: +1 669 254 5252
  2. County Council Committee Meeting September 2026 

📝Review the Presentation 

Integrated Wastewater Management Plan Presentation

📩Get in Touch:

• Cesspool Rules & Permitting (DOH): webmail@doh.hawaii.gov
• Evaluation Report (County DEM): cohdem@hawaiicounty.gov | 808-961-8099

💡Learn More

• Hawaiʻi Department of Health
• US Environmental Protection Agency

CONTACT US

 ✉️ cohdem@hawaiicounty.gov

📞 808-961-8099