Cesspool Conversion in Puna, Hawaiʻi Island
Puna properties may rely on catchment, private wells, or available public water depending on location. Wastewater design must account for water sources, setbacks, lava terrain, groundwater, lot size, and access.
If you own property in Puna and need to convert your cesspool, these conditions make the process different from other parts of the island.
What makes Puna challenging
Very high groundwater tables. In Puna, groundwater often sits just a few feet below the surface. A standard septic system needs dry soil for its disposal field to work properly. When water is that close, most properties need an aerobic treatment unit (ATU), which treats wastewater more thoroughly before it leaves your property. ATUs cost more upfront and require ongoing maintenance with regular pump-outs.
Private wells in many areas. Many households in Puna rely on private wells for drinking water. The DOH requires strict setbacks between your disposal field and any well, typically 100 feet or more depending on elevation differences. On smaller lots, meeting those setbacks can be difficult and may require creative engineering solutions.
Volcanic activity history. Parts of Puna were affected by the Kīlauea eruption that began in May 2018. If your property is in or near the impacted zone, additional environmental review may be required before a wastewater system permit can be approved. Soil conditions in these areas have changed significantly since the eruption.
Sewer availability
Puna does not have municipal sewer service in most of the district. Some newer developments and areas near Keaʻau may have access to public sewer lines. If your property is close enough to connect, that eliminates the need for a cesspool conversion entirely. For properties without this option, individual wastewater systems remain the path forward.
The process: same steps, unique conditions
Site visit. A licensed civil engineer evaluates your soil type, water table depth, available space for a disposal field, and distance to wells. In Puna specifically, the engineer pays close attention to groundwater levels that often dictate whether an ATU is required instead of a standard septic system.
Design and permitting. The engineer creates an Individual Wastewater System (IWS) plan tailored to your property conditions and submits it to the Hawaiʻi DOH. Puna properties tend to take longer in this phase because ATU designs require more detailed review from the DOH, including water quality impact assessments near well clusters.
Installation. A licensed installer excavates, sets the tank and components, runs pipe lines, backfills, and restores your yard. Puna's warm climate means fewer weather-related delays during installation compared to Hilo or North Kohala.
Ongoing maintenance. If your property requires an ATU (which most do), plan for regular pump-outs every 3-6 months and occasional electrical component replacement. This is an ongoing cost that does not exist with a standard gravity-fed septic system.
Selling property in Puna
A cesspool can complicate a sale, refinance, inspection, or buyer negotiation because people may ask about conversion cost, timing, risk, and compliance. An engineer assessment gives the owner clearer information before listing, negotiating, remodeling, or planning future work.
Getting started
The first step is a site visit by a licensed civil engineer who understands Puna groundwater conditions and DOH requirements for this area. They will tell you whether your property can support a standard septic system or requires an ATU, and give you a realistic cost range before any major expense.
If you want help connecting with an engineer familiar with the southeast coast, tell us about your property. It takes two minutes and there is no commitment, just a clearer picture of what your conversion looks like on paper.
This article is for informational purposes only and does not constitute legal or engineering advice. Actual costs and timelines vary by property. Hawaiʻi Cesspool Help coordinates between homeowners and licensed professionals — we do not provide engineering services directly.