Septic Installation & Cesspool Conversion in Volcano Village
We install septic systems and convert cesspools in Volcano Village and the subdivisions around it, about 30 minutes up Highway 11 from our equipment yard in Keaau. Volcano is nothing like the lava lots of lower Puna. It’s high, cool and wet, it sits on volcanic ash rather than bare rock, and since late 2024 it has had to deal with tephra falling out of the sky.
Volcano at a Glance
- 2020 population. The Census counted 736 people in 387 households in the Volcano CDP. The neighboring Volcano Golf Course area is counted as its own CDP, with 363 residents in 2020.
- Elevation of about 3,700 to 4,000 feet. The CDP stretches from below 2,800 feet in the southeast to an uninhabited northern end above 6,200 feet. Highway 11 runs through the southern part.
- A lot of rain, and cool. The University of Hawaii Rainfall Atlas puts most of the village at roughly 115 to 125 inches a year. At the national park headquarters next door, the 1991 to 2020 normals show rain on about 295 days a year and an average daily low of 53 degrees.
- Next to the national park. Volcano sits on the border of Hawaii Volcanoes National Park, 27 miles from Hilo by Highway 11.
- Catchment water. For many households here, rainwater catchment is the main source of water for everyday use.
- No DOH priority area. Volcano is not one of the five Hawaii Island priority areas in the 2017 DOH report. You can check your own parcel on the UH Cesspool Prioritization Tool.
Ash Soils, Not Lava Rock
Most of Puna is a lava rock problem. Volcano is more often a wet soil problem. NRCS describes the Puaulu soil series from a site just off Highway 11 in the Volcano quadrangle at about 3,800 feet. It formed in volcanic ash over lava, it’s deep (the reference profile runs 60 inches without hitting rock), and it occurs between 3,200 and 4,500 feet where rainfall runs 110 to 160 inches. NRCS rates it moderately well drained with moderate permeability. Its classification includes the term “aquic,” which means the soil stays wet near the surface for part of the year.
What that means for a septic system here:
- The soil profile matters more than the rock. The engineer’s 5-foot soil profile and percolation test decide the design. On a deep ash lot, a conventional tank and leach field may work without a soil replacement bed.
- Seasonal wetness is the thing to watch. HAR 11-62 requires at least 3 feet of separation between the bottom of the disposal area and groundwater. Wet ash soils can show signs of a high water table, and that can push a design toward a raised field or a different system.
- Not every lot is deep soil. Closer to Kilauea, lava flows and spatter come nearer the surface. The profile is what settles it, lot by lot.
- Cool soil, steady rain. A leach field here takes rain on most days of the year, so drainage around the field and keeping roof runoff away from it count.
Cost drivers differ from lower Puna. There it’s rock removal and imported fill. Here it’s more often site drainage, field sizing in wet soil, and access through wooded lots. Our conversion cost guide breaks down where the money goes.
Tephra, Catchment and Your Septic
Kilauea’s current summit eruption began on December 23, 2024, and has gone on in fountaining episodes since, with episode 54 on August 25, 2026. Several episodes dropped tephra on neighborhoods outside the park. USGS reported tephra from the Volcano Golf Course to Ohia Estates during episodes 15 and 16. In April 2026, episode 44 sent it toward Kilauea Military Camp and the Volcano Golf Course subdivision, and Hawaii County Civil Defense opened a tephra information center at the Cooper Center in Volcano Village. In June 2026, volunteer plumbers installed catchment diverters at 30 Volcano homes so owners could send rainwater away from their tanks while ash was on the roof.
For wastewater, the practical point is simple: keep tephra out of the system. When you clean it off roofs, decks and driveways, don’t wash it into floor drains or toward tank lids, cleanouts or the leach field. Gritty material that ends up in a septic tank takes up space the tank needs. If your tank lids sit at grade, a quick check after a heavy fall is worth it.
What Volcano Homeowners Usually Need
- Older homes on cesspools. The village’s historic residential district includes homes from as far back as the 1930s. Any home built before 2016 may have a cesspool, and the 2050 deadline applies.
- Guest cottages and vacation rentals. Many park visitors stay in the village. A cottage usually means more bedrooms on the permit, which can lead DOH to require a wastewater upgrade. Under the rules, a 70-square-foot room counts as a bedroom.
- Owner-builder homes on forested lots. On Hawaii Island, the DOH wastewater review comes before the county building permit. Our new home septic requirements guide covers the steps.
- Buying or selling. A sale does not trigger conversion, but buyers here ask about it. See our guide to buying or selling a home with a cesspool.
Getting In: One-Lane Roads and Tree Cover
Some streets in the older part of the village are one lane, and many lots are wooded. Before we schedule an excavator, we want to know the width of the road and driveway, any overhead branches or lines, and where a truck can turn around. Wet ground also matters. After a long rainy stretch, we may need to wait for the site to firm up before digging so we don’t rut the yard or the field area.
Rules and Funding That Apply Here
- 2050 deadline. Volcano cesspools have until January 1, 2050 under Act 125. Our Act 125 explainer has the details.
- Sewer. Ask the county Department of Environmental Management if you’re unsure about service on your street.
- Funding. USDA Section 504 offers repair loans to very-low-income rural owners and small grants to those 62 and older, so check eligibility with the USDA office in Hilo. The state’s Act 204 loan fund is expected to open in late 2026.
- ATU upkeep. If the design calls for an aerobic treatment unit, it needs a service contract with inspections every six months.
Other Volcano-Area Pages
Plan Your Volcano Project
Tell us where the house is, whether it has a cesspool now, and whether you plan to add a cottage or bedrooms. We’ll talk through what the soil and the site are likely to need. Request a free estimate
Frequently Asked Questions
Do Volcano lots need soil replacement like lower Puna?
Not always. Many Volcano lots have deep volcanic ash soil, so a conventional field may work. The engineer’s soil profile and percolation test decide.
Does the wet climate make septic harder at Volcano?
It can. With rain most days of the year and ash soils that stay wet for part of it, the 3-foot separation to groundwater and drainage around the field get extra attention.
Can tephra damage my septic system?
Tephra in the tank or field area is something to avoid. Keep it away from tank lids, cleanouts and drains when you clean up after a fall.
I want to turn my Volcano cottage into a rental. Does that affect my cesspool?
If the building permit adds bedrooms, DOH can require an upgrade. It’s better to plan the septic work with the remodel than to find out at permit review.
Is Volcano a cesspool priority area?
It isn’t one of the 2017 DOH priority areas. The 2050 deadline still applies, and you can look up your parcel on the UH prioritization tool.
Will my septic system affect my catchment water?
A properly designed and sited system shouldn’t. Tell the engineer where your catchment tank and lines are so the layout keeps them apart.