By Benjamin Finnerty (S), REALTOR® (RS-83812) with Keller Williams Realty Maui · Kīhei, Maui · 808-481-9748

Quick Answer: Hawaiʻi’s Act 125 (2017) requires every cesspool to be upgraded, converted to septic or connected to sewer by January 1, 2050. Act 204, signed July 9, 2026, creates a Cesspool Conversion Revolving Loan Fund through the Hawaiʻi Green Infrastructure Authority, seeded with $2 million, offering low-interest or forgivable loans toward the typical $25,000–$50,000 conversion cost.

I’m Benjamin Finnerty, a REALTOR® in Kīhei with Keller Williams Realty Maui, and if you’re shopping for a home in Kula, Olinda, Haʻikū or anywhere else Upcountry, cesspools are one of the due diligence items I want on your radar early. There’s a good chance the property you’re eyeing has a cesspool instead of a septic system or sewer connection. This summer, Hawaiʻi finally put real money behind its cesspool deadline, and that changes how buyers, sellers and current owners should think about it.

What Is Hawaiʻi’s Cesspool Conversion Deadline?

The deadline is January 1, 2050. Act 125, passed in 2017, requires every cesspool in the state to be upgraded, converted to an approved individual wastewater system, or connected to municipal sewer by that date.

That date isn’t new. What’s new in 2026 is a financing tool. The current pace of conversions statewide is well short of what’s needed to hit the 2050 deadline, which is exactly why lawmakers created one.

What Does Act 204 Change for Maui Homeowners?

Act 204 creates a state loan program to help pay for cesspool conversions. Governor Josh Green signed it on July 9, 2026 (it was House Bill 1618).

The law creates the Cesspool Conversion Revolving Loan Fund, administered by the Hawaiʻi Green Infrastructure Authority (HGIA) and capitalized in part through the state’s Water Pollution Control Revolving Fund. Here are the key points:

• Seed money: $2 million in state Green Fee funds.
• Loan types: low-interest, and in some cases forgivable, loans.
• What it helps cover: conversion costs, which typically run $25,000 to $50,000 depending on the system and site conditions.
• Staffing: the legislature also funded a dedicated program manager position to get the fund running.
• Timing: HGIA is setting up the details now and has not yet announced when applications will open.

How Many Cesspools Are on Maui, and Where Are They?

Roughly 12,000 of Hawaiʻi’s estimated 88,000 cesspools are on Maui, according to the state Department of Health’s Wastewater Branch. That puts Maui behind Hawaiʻi Island (about 50,000) and Kauaʻi (about 14,000) in raw numbers.

Location matters more than the count. The DOH has designated Upcountry Maui one of just 14 “priority upgrade areas” statewide, and one of the very few ranked Priority 1, the highest urgency tier, reserved for cesspools posing the most significant risk to drinking water and sensitive coastal and stream ecosystems.

Kula, Olinda, Haʻikū and Maui’s North Shore rural pockets show up repeatedly in state data as areas where cesspools remain common on older parcels, along with some clusters near Wahikuli just north of Lahaina. In plain terms: if you’re buying or selling in one of these areas, cesspool status isn’t a footnote. It’s a real cost variable that regulators are actively watching.

What Should Buyers Check on an Upcountry Property With a Cesspool?

Confirm the wastewater system first. A cesspool isn’t automatically a dealbreaker, but it should factor into both your offer and your due diligence.

• Ask directly whether the home has a cesspool, septic system or sewer connection.
• Don’t rely only on the seller’s disclosure. Cesspools are sometimes buried, capped or simply unknown to sellers who inherited older systems.
• Check the map. The University of Hawaiʻi Sea Grant’s Cesspool Hazard Assessment & Prioritization Tool is a public interactive map that shows a property’s general risk tier based on DOH data.
• Price it in. If a conversion is likely in your near-term future, the $25,000–$50,000 range is a legitimate number to bring into negotiations, whether as a price adjustment, a seller credit or a budget line after closing.
• Ask about financing. Once the HGIA program opens, ask your lender or an HGIA representative whether a loan fits your timeline.

Water is the other big Upcountry question. If you’re looking at land, read my guide to the Upcountry water meter waitlist for Kula, Makawao and Haʻikū land, and for the bigger picture, my post on why buyers are looking at Kula, Makawao and Pukalani.

What Should Sellers Do If Their Home Has a Cesspool?

Get ahead of it rather than waiting for a buyer’s inspector to raise it. Some sellers convert before listing, particularly in Priority 1 zones where buyers and their agents increasingly ask the question upfront. Others price the eventual cost into the listing and disclose clearly.

Either approach can work. What tends to hurt sellers is surprise: a cesspool discovered mid-escrow erodes trust and can stall or reprice a deal that was otherwise moving smoothly.

My Take: What I’m Telling Upcountry Buyers and Sellers

The 2050 deadline is far off, but the money and the attention are arriving now. With Upcountry Maui ranked Priority 1, I expect cesspool status to keep coming up in negotiations, and I’d rather my clients address it on day one than on day twenty of escrow.

For buyers, my approach is simple: identify the system early, look up the property’s risk tier, and treat the $25,000–$50,000 conversion range as part of the purchase math. Whether it shows up as a lower price, a credit or a planned project, it shouldn’t be a surprise.

For sellers, I’d get a clear answer on the system before listing and decide upfront whether to convert or disclose and price accordingly. Both paths are defensible. Leaving it vague usually isn’t.

This is general information, not legal advice. Please confirm your situation with a Hawaiʻi attorney and a licensed wastewater professional.

Frequently Asked Questions

Do I have to convert my cesspool right now?

No. The statewide deadline is January 1, 2050. There’s no requirement to convert immediately unless a local ordinance, lender or specific transaction requires it.

Is Hawaiʻi considering moving the cesspool deadline up?

Lawmakers have discussed accelerating the timeline to 2035–2040 for the highest-risk cesspools, but no such change has been enacted as of this writing.

How do I find out if a property is in a cesspool priority zone?

The DOH-backed Cesspool Hazard Assessment & Prioritization Tool, maintained by University of Hawaiʻi Sea Grant, lets you look up general risk data by area.

Will the new HGIA loan program be open to Maui homeowners?

Yes. The HGIA Cesspool Conversion Revolving Loan Fund is a statewide program. HGIA has not yet announced an application date, so check with HGIA directly for the latest.

Ask Benjamin

Whether you’re weighing an offer on a Kula acreage lot, thinking about listing a Haʻikū property, or trying to understand what you’re inheriting with an older Upcountry home, I’m happy to help you sort out what a property’s wastewater situation means for your timeline and budget. I’m Benjamin Finnerty, and you can call or text me at 808-481-9748 or email benjamin@the808team.com. No pressure, just a straight answer about where things stand.