Septic companies in Hawaii

Who Regulates Septic Systems in Hawaii

Sources: Hawaii State Department of Health, Wastewater Branch. Checked 2026-09-21.

Hawaii approves wastewater systems from the state, through the Department of Health Wastewater Branch. Your county issues the building permit, and the wastewater review is a separate state process that your engineer drives. Septic is also the wrong word for a lot of property here, because what is in the ground is often a cesspool.

The state's own term for a house system is an individual wastewater system. An IWS is typically required for single family homes with flow rates less than 1000 gallons per day opens in a new tab, and the Wastewater Branch issues an approval to construct to the engineer once the design complies with its rules opens in a new tab. Above that flow you are into treatment works, which is a heavier process.

Your county does have a part, and it is the building permit. For the status of a building permit application the Department of Health sends you to your local county building department opens in a new tab, while the wastewater approval stays with the state. Two applications, two offices, and they do not wait for each other.

Licenses and What to Check Before You Hire

Sources: Hawaii State Department of Health, Wastewater Branch. Checked 2026-09-21.

Hawaii's answer to who you hire first is unusual, because it is an engineer rather than a septic contractor. The Department of Health's own guidance is to hire a licensed wastewater engineer for help with your specific system opens in a new tab, and the branch primarily communicates with only the engineer to keep the review moving opens in a new tab. If you are not talking to an engineer, you are not in the process yet.

That arrangement also sets what you can expect on timing. The branch has at most one reviewing engineer for each county against thousands of applications a year opens in a new tab, so the queue is real and a slow answer is usually not your engineer stalling. Ask your engineer for the submission date and the comment history rather than a promise.

Pumping carries its own state credential, and it is worth asking about. Cesspools and septic tanks must be regularly pumped by a registered pumper and hauler opens in a new tab, so ask whether the truck at your house belongs to one. We hold no Hawaii register of our own, so no listing on this site carries a verified credential for this state.

Permits, Inspections and Selling a Home

Sources: Hawaii State Department of Health, Wastewater Branch. Checked 2026-09-21.

Hawaii puts the cost of a non-compliant system on the buyer, which makes diligence here worth more than anywhere else on this site. If the wastewater system on the property is not in compliance with the rules, the new homeowner will be held accountable for bringing it into compliance along with any costs that it may entail opens in a new tab. Read that once more before you waive an inspection.

The deadline behind that warning is fixed in statute. Before 1 January 2050, every cesspool in the state must be upgraded to an individual wastewater system or connected to a sewer system opens in a new tab, and a homeowner in violation of the water pollution chapter can be fined up to $60,000 for each separate offence, with each day counting as a separate offence opens in a new tab. A cesspool is a liability with a date on it.

There is also a plain test for whether the thing has already failed. A cesspool that has been pumped more than twice in the last 12 months counts as failing opens in a new tab, so ask the seller for pumping receipts rather than reassurance. Receipts are the only honest record of a buried system.

Scale is the other thing a buyer should price in. There are approximately 88,000 cesspools in the state, with nearly 50,000 on the Big Island, almost 14,000 on Kauai, over 12,000 on Maui, over 11,000 on Oahu and over 1,400 on Molokai opens in a new tab, and 43,000 of them pose a risk to water resources opens in a new tab. Everyone on your island is queueing for the same engineers and the same excavators.

Keeping a System Working

Sources: Hawaii State Department of Health, Wastewater Branch. Checked 2026-09-21.

Hawaii gives an interval for the whole system rather than just the tank: an individual wastewater system should be inspected about every 5 years to ensure continued operation opens in a new tab. Cesspools and septic tanks also have to be pumped regularly, by a registered pumper and hauler, to prevent overflows and backed up wastewater opens in a new tab.

Help Paying for Repairs

Sources: Hawaii State Department of Health, Wastewater Branch. Checked 2026-09-21.

Hawaii runs the largest conversion effort in the country, and the money is moving again this year. Act 125, passed in the 2017 legislative session, requires the replacement of all cesspools by 2050 opens in a new tab, and cesspools in Hawaii release approximately 53 million gallons of untreated sewage into the ground each day opens in a new tab, which is why the state keeps funding the work. Check the Department of Health's support page before you commit to anything.

The live statewide programme is a loan rather than a grant, and one word in it matters. The 2026 Cesspool Conversion Revolving Loan Program offers low-interest or forgivable loans for eligible households to upgrade or convert existing cesspools in all counties, or to connect a property to a sewer opens in a new tab. Forgivable is the term to ask the administering authority about.

County money exists too, and Kauai's round is the one with numbers on it. Kauai County's second residential cesspool conversion grant round put 50 grants of $20,000 on the table opens in a new tab, and eligibility runs off the state's priority areas, where Priority 1 means cesspools that present a significant risk of human impacts, drinking water impacts or draining to sensitive waters opens in a new tab. Find your priority area before you spend a day on an application.

One correction, because older advice still repeats it as if it were live. The Department of Health lists the 2016 to 2020 income tax credit for a qualified cesspool, worth $10,000, under completed programmes alongside the 2023 pilot grant opens in a new tab. Do not budget around that credit without checking what applies in the current tax year.

What Your County Does, and Does Not, Do

Hawaii approves wastewater systems from the state, through the Department of Health Wastewater Branch, so no county here issues the septic approval. Your county building department handles the building permit, which is a separate application on a separate clock. Kauai County is the one with its own money attached, a residential cesspool conversion grant covered further down this page. Checked 2026-09-21.

Questions People Ask