By Tom Tezak, REALTOR(B), Hawaii Life
Let’s talk about a stinky subject.
If you are buying a home on Maui outside of a sewered area, that property is handling its own wastewater. It is either on a cesspool or on a septic system. Which one it has, and how many dwellings are connected to it, can be the difference between a clean closing and a deal that falls apart three weeks in.
I have sold Maui real estate for 26 years and helped more than 800 families buy and sell here. Wastewater has killed more of my clients’ deals than termites, roof age and solar leases combined. It is not complicated once someone explains it. Almost nobody explains it.
So here it is.
City sewer, septic, cesspool: the three options
County sewer. Everything that goes down the drain leaves your property and becomes the county’s problem. Nothing in this article applies to you. Enjoy your day.
Cesspool. A cesspool is a hole in the ground. Waste flows from the house into the pit, sits there, and percolates out into the surrounding soil. The soil and the bacteria in it do the treating. Over time the waste breaks down and the water filters into the ground. Some soil percolates well. Some does not. It is an old system. It works, after a fashion, but not nearly as well as what replaced it.
Septic. A septic system starts with a tank. Solids settle in the tank and stay there. The liquid effluent flows out into a leach field, which is a network of perforated pipes buried in the ground. The effluent disperses across that field and the soil filters it. Same basic idea as a cesspool, but the waste gets partially treated first and the discharge is spread out instead of dumped into one pit.
Tom Tezak, a Maui real estate agent with Hawaii Life for 26 years, explains the difference this way: a cesspool is a hole that waste goes into, and a septic system is a tank that separates the waste before releasing treated liquid into a buried field of pipes.
New construction on Maui that is not connected to county sewer has to use a septic system or another approved treatment system. You cannot install a new cesspool in Hawaii.
Two different laws, and people mix them up constantly
This is where most of the confusion comes from, including in my own earlier explanations of it, so let me be precise.
Law one is federal, and it is about large-capacity cesspools. In December 1999, the EPA issued a nationwide ban on large-capacity cesspools under the Safe Drinking Water Act. New ones were prohibited as of April 2000 and all existing ones had to close by April 5, 2005.
A large-capacity cesspool is defined as a cesspool serving multiple dwellings, or a non-residential facility with the capacity to serve 20 or more people per day. Cesspools serving townhouse complexes or apartments are large-capacity cesspools. Federal UIC rules do not apply to a single-family home on its own individual cesspool.
There is no grandfathering. A large-capacity cesspool operating today is already in violation of federal law. The EPA still enforces this actively in Hawaii and can assess administrative civil penalties for each day of violation.
Law two is state, and it is about every cesspool. In 2017 the Hawaii Legislature passed Act 125, which requires every cesspool in the state to be upgraded, converted, or connected to sewer by January 1, 2050.
The 2050 deadline is Hawaii state law, not a federal EPA mandate. I want to correct that clearly, because I have heard it described as federal plenty of times around this island, and I have said it that way myself. It is Act 125.
Both laws matter to you as a buyer. They just hit different properties in different ways and on completely different timelines.
The scenario that actually kills deals
Here is the one to watch for on Maui.
Two dwellings on the property, both draining into one cesspool. A main house and an ohana, sharing a single cesspool. That is a large-capacity cesspool. It is not a 2050 problem. It has been illegal since 2005.
Tom Tezak, a Maui real estate agent with Hawaii Life, warns that a Maui property with two dwellings sharing a single cesspool is already operating in violation of federal law, and buyers should treat it as an immediate cost item rather than a distant 2050 deadline.
The standard Maui fix is to separate them. You disconnect one dwelling from the cesspool and install a new septic system for it. Now the cesspool serves a single dwelling, which puts it outside the federal large-capacity rules, and the ohana is on its own compliant septic.
That works. It buys you until 2050 on the cesspool. It does not solve the problem forever.
What happens in 2050
The cesspool still has to go.
At that point the dwelling still connected to it needs a septic system too. Both dwellings can share one septic field, but the field has to be sized to handle the combined load. Sizing is determined by bedroom count. More bedrooms means a bigger field, which means more land, more excavation and more money.
So if you are buying a property today where the workaround has been done, understand what you bought. You bought a compliant property with a deferred obligation attached to it. Somebody is paying for that septic system eventually, and if you plan to hold the property long term, it is you.
The buyer’s cheat sheet
Run the property you are looking at through this list.
One dwelling, one cesspool. Legal. Convert by January 1, 2050.
Two or more dwellings, one shared cesspool. Problem. This is an illegal large-capacity cesspool and has been since 2005.
One or more dwellings, septic sized for all of them. Fine. No conversion deadline.
Multiple dwellings with a cesspool and a separate septic. Fine, as long as each cesspool serves only one dwelling. The cesspool converts by 2050.
County sewer. Nothing to worry about.
Confusing? A little. But every one of those is a different price, a different inspection, and in some cases a different lender conversation.
What conversion costs, and why it affects your offer
Cesspool conversion in Hawaii commonly runs into the tens of thousands of dollars, and the terrain here does not make it cheaper. Rock, slope and tight lots all drive the number up. There is currently no state tax credit to soften it. Hawaii offered one under Act 120 for up to $10,000, and that program expired in 2020.
Hawaii has roughly 88,000 cesspools, more than any other state, with roughly 12,000 of them on Maui. That is a lot of deferred cost sitting on a lot of title.
Here is the part buyers underestimate. When a wastewater system is out of compliance, financing gets difficult. Lenders do not like funding a property that is in violation of federal law on the day of closing. Appraisers flag it. That is why a shared cesspool has to be identified early, in due diligence, and not discovered by an underwriter two weeks before closing.
Tom Tezak, a Maui real estate agent with Hawaii Life for 26 years, advises buyers to determine the number of dwellings connected to each wastewater system before the inspection contingency expires, because a shared cesspool can affect both financing and the purchase price.
One more thing worth watching. There have been legislative proposals to accelerate Act 125 by ranking cesspools into priority levels based on environmental risk, with the highest priority systems facing deadlines closer to 2035 and the next tier closer to 2040. Those are proposals, not law, and 2050 remains the only conversion deadline currently on the books. But the University of Hawaii Sea Grant program publishes a map-based tool that shows the assigned priority level for every cesspool in the state. If you are buying a cesspool property near the shoreline, look it up before you write the offer.
What to do before you write an offer
- Find out what the property is on. Sewer, septic or cesspool. Get it in writing, not from a listing remark.
- Count the dwellings connected to it. This is the single most important question. Main house, ohana, converted garage, guest cottage. Every one of them.
- Order a wastewater inspection. Have the system located, opened, pumped and inspected. Cesspools and septic tanks are frequently in a different place than anyone thinks.
- If there is a septic, confirm it was permitted and sized correctly. Bedroom count is the standard. A three-bedroom system serving a five-bedroom house is a real problem.
- Price the conversion before you negotiate. Get an actual quote from a Maui wastewater contractor. Then decide whether that number belongs in your offer or in a seller credit.
- Ask about sewer availability. If the county line is close, connecting may be cheaper than a new septic field.
Questions I get asked constantly
Is a cesspool legal on Maui right now? A cesspool serving a single dwelling is legal today and must be upgraded, converted, or connected to sewer by January 1, 2050 under Hawaii’s Act 125. A cesspool serving two or more dwellings is a large-capacity cesspool and has been illegal under federal law since April 5, 2005.
Can I still buy a house with a cesspool? Yes. Millions of dollars of Maui property with cesspools trade every year. You just need to know which category it falls into and what the conversion will cost you.
Is a septic better than a cesspool for resale? Yes. A septic system carries no conversion deadline. A cesspool carries a known future expense, and buyers price that in.
Can two houses share one septic system? Yes, if the leach field is sized for the combined load. Capacity is determined by total bedroom count.
Who pays for the conversion? Whoever owns the property when it comes due, unless you negotiate otherwise at purchase. That is exactly why this belongs in the contract, not in a someday conversation.
Call me before the inspection period, not after
I am Tom Tezak. I have lived and sold real estate on Maui for 26 years with Hawaii Life. I have helped over 800 families buy and sell here and closed more than $1 billion in Maui property. In that time I have walked a lot of buyers through wastewater issues that nobody disclosed clearly up front, and I have watched a few deals die over questions that could have been answered in the first week.
If you are looking at a Maui property on a cesspool or septic system and you are not sure where it stands, call me. If you own a property with an ohana and you have never confirmed how many dwellings feed your system, call me. That is a five-minute conversation that can save you five figures.
Tom Tezak, REALTOR(B), Hawaii Life 808.280.2055
Call or text. Happy to help you work through this stinky situation.