Septic Installation & Cesspool Conversion in Hawaiian Acres
We install septic systems and convert cesspools in Hawaiian Acres, the big ohia-forest subdivision above Kurtistown, a short drive up from our equipment yard in Keaau. What makes Hawaiian Acres different is its size and elevation: lots of about 3 acres, ground that climbs from 650 to 1,350 feet, rain approaching 200 inches a year at the top, and 72 miles of mostly unpaved road that nobody is required to pay to maintain.
Hawaiian Acres Facts That Affect a Septic Job
- Population: 3,426 in the 2020 Census, nearly double the 1,776 counted in 2000.
- Housing units: 1,569 in 2020, with 11.9 percent vacant.
- Size: 19.43 square miles, more land than HPP, Orchidland or Kurtistown.
- Origins: In 1958, Tropic Estates bought 12,191 acres between Kurtistown and Mountain View and divided it into 4,008 lots. They sold for $500 to $1,000, with no infrastructure.
- Lot size: most are about 3 acres.
- Elevation: 650 to 1,350 feet, according to the community association.
- Rainfall: 130 to 200 inches a year, per the association. The UH Rainfall Atlas shows about 164 inches near the center.
- Lava: flows 200 to 750 years old across most of the subdivision, with some lots along G Road on flows about 3,000 years old. USGS places Hawaiian Acres on the Ailaau (Kualoloa) flow field, and the association says it’s in Lava Hazard Zone 3.
- Water: the association says all homes use rain catchment.
Building a Leach Field Under Ohia Forest
Most of Hawaiian Acres is ohia forest with tree ferns and an understory of introduced guava and Tibouchina. Before we can dig a leach field, the area has to be cleared, and that clearing should be limited to what the system, the house and driveway actually need. Tree roots near the field are a long-term problem, so your engineer and we will plan the layout with that in mind.
Under the forest, the ground is young lava. Where it’s fractured, the state wastewater rules call for a soil replacement system, meaning the trench is cut into rock and backfilled so there are at least three feet of filtering material above groundwater. Older ground along G Road may have more weathered material on top, but you won’t know until the engineer digs the test pit for your lot.
Rain is the bigger day-to-day factor. At up to 200 inches a year, there are stretches when the ground and the roads never really dry out. The association also notes that overflow from the county’s Mountain View drainage project can run five feet or more deep in heavy storms, and that Olaa Sugar’s diversion walls, built starting in 1938, send floodwater through parts of the subdivision. If your lot sits near one of those flow paths, tell your engineer before design.
Owner-Builders and Off-Grid Homes
Hawaiian Acres lots were sold with no infrastructure, and residents have long done a lot for themselves. The association’s history says early residents had no electricity and used outhouses, and many households still run on solar, generators or wind. The association describes homes today as using septic systems. Any house built before March 2016 could still have a cesspool, though, and no new cesspools have been allowed statewide since then.
The projects we see most often here:
- New homes on wooded lots. The county won’t finish your building permit until DOH has reviewed the wastewater plan. Our new home septic requirements article lays it out.
- Permitting an older owner-built house. A building permit on Hawaii Island brings a DOH review of the wastewater system, and adding bedrooms can lead DOH to require an upgrade. Lofts and bonus rooms can count as bedrooms.
- Ohana units. State rules cap a single system at five bedrooms. A main house with an ohana can go over that, and a 3-acre lot leaves room for a second system if you need one.
If you have a cesspool from before 2016, it has to be converted or upgraded before January 1, 2050. Our Act 125 explainer covers the details.
72 Miles of Road and No Mandatory Dues
Here’s the issue every Hawaiian Acres homeowner knows. The subdivision has 72 miles of private road, and fewer than 10 are paved, according to the Hawaiian Acres Community Association (HACA). Road dues are voluntary. HACA and the Hawaiian Acres Road Corporation (HARC) maintain the unimproved roads with those dues and volunteer work, and they say it isn’t enough for even minimal upkeep.
Residents have pushed for a fix. In a 2020 HACA survey, nearly 600 of 714 respondents favored a road improvement district. When Puna’s council member brought a resolution in 2021, county officials gave preliminary estimates of more than $16 million just to study the roads and about $837 million to bring all of them up to county standards. The committee postponed it. In January 2024, the Tribune-Herald reported that the County Council had unanimously passed Bill 82, which lets county funds patch and resurface some privately owned roads that serve at least 50 parcels, mainly to improve emergency access.
For a septic job, the practical result is that the last stretch to your lot may be gravel, potholed or soft. Before we schedule, we drive the route with the excavator trailer and tank truck in mind. Lots far up the numbered roads take longer to reach, and after a big storm we may wait a day or two for the road to firm up.
What Hawaiian Acres Jobs Cost and Who Can Help
Statewide, most conversions run about $20,000 to $50,000; septic tank and leach field jobs about $20,000 to $40,000. Lava rock, forest clearing and long gravel access add to the total in Hawaiian Acres. Our cost guide explains the line items.
Owners on limited incomes should look at USDA’s Section 504 program, which makes low-interest repair loans and, for seniors, small grants; the Hilo office can tell you if you qualify. Our grants and loans page also follows the new state loan fund that HGIA plans to open.
Neighboring Communities
Hawaiian Acres borders Kurtistown, Mountain View, Fern Acres and Orchidland Estates. See Puna septic services for the whole district.
Walk the Lot Before You Buy or Build
Tell us which road you’re on and how far in. We’ll look at the access, the forest and the rock, and explain what your system will take. Request a free estimate
Frequently Asked Questions
Will your trucks make it to a lot on an unpaved Hawaiian Acres road?
Usually. We check the route first, because conditions vary a lot from road to road. After heavy rain we may hold off until soft spots dry out.
Do I have to pay Hawaiian Acres road dues before you can work?
That’s between you and the association; HACA’s road dues are voluntary. Paying them does help keep the roads passable for everyone, including the trucks delivering your tank.
How much forest needs to be cleared for a leach field?
Only the system footprint plus working room. Your engineer’s plan sets the size, and we try to keep large trees well away from the field so roots don’t get into it later.
My lot is near a drainage channel. Is that a problem?
It can be. HACA reports that drainage overflow can run five feet deep in big storms. Your engineer will keep the system out of flow paths and meet setback rules.
I have an old owner-built house with no permit. Can I still get a septic system?
Yes. A licensed engineer designs it and DOH reviews it. If the house is being permitted at the same time, the DOH review comes first.
Does the 3,000-year-old ground on G Road make septic easier?
Possibly. Older flows can have more weathered material, but there’s no guarantee. The soil profile on your lot is what counts.