Cesspool Priority Tool Walkthrough for Big Island Homeowners
The Hawaiʻi Cesspool Prioritization Tool shows a screening priority for mapped cesspools. A rating does not tell you the condition of a cesspool, the system a property needs, the project cost, funding eligibility, or the deadline for a particular property. Use it as background information and have the property evaluated by a licensed professional.
1. Confirm the wastewater system
Check utility bills, seller records, cesspool cards, approved plans, and other property documents. A listing may call a system “septic” even when the records show something different.
If the system type remains unclear, gather the TMK and any records you have. Hawaiʻi Cesspool Help can connect you with a licensed professional who can evaluate the property.
2. Check the mapped priority rating
Use the Hawaiʻi Cesspool Hazard Assessment and Prioritization Tool to review the mapped rating. Save the result with the date you checked it.
The rating is a statewide planning tool. It should not be used by itself to predict approval, system type, site conditions, cost, or timing.
3. Check current legal requirements
State law sets a general deadline to upgrade, convert, or close cesspools before January 1, 2050, subject to exemptions and other applicable requirements. Current DOH guidance also identifies circumstances that can require action sooner, including certain building modifications, nuisance or health conditions, excessive pumping, repeated spills, and direct disposal into groundwater.
A property sale does not automatically create an earlier statewide conversion deadline. Review the current DOH guidance and the facts for the property before drawing a legal conclusion.
4. Get the property evaluated
A Hawaiʻi licensed civil engineer must prepare and submit an individual wastewater system design. The final design depends on the property, wastewater flow, soils, setbacks, access, and DOH requirements.
Start with Hawaiʻi Cesspool Help. We collect basic property information and connect homeowners with licensed professionals who can evaluate the property and explain the next steps.
5. Understand approvals and funding
The DOH homeowner process includes design review, approval to construct, installation, construction documentation, and approval to use. The work and review time vary by property, design, contractor availability, and agency requirements.
DOH lists a 2026 Cesspool Conversion Revolving Loan Program that is under development and expected to be administered by the Hawaiʻi Green Infrastructure Authority. Check the official program page for current details. Eligibility, rates, application dates, and available funds should not be assumed before the agencies publish them.
6. Keep the result with the property records
Save the priority result, system records, approved plans, inspection documents, maintenance information, and agency correspondence together. Future maintenance depends on the installed system and its approved operating requirements.
Need help after checking the priority tool?
Send the TMK, the result, and your main property question. We will help connect you with a professional when a review of the property is needed.