Septic Installation & Cesspool Conversion in Keaau

We install septic systems and convert cesspools in Keaau, the town where our excavators are based. Keaau is the crossroads where Highway 11 and Highway 130 meet, so every trip we make into Puna starts here. The town also gave its name to the cesspool priority area that covers much of the district.

Keaau Facts That Affect Septic Work

  • 1,195 residents and 382 households in the Keaau census area in 2020. That area only covers the village itself, not the big subdivisions people often call Keaau. The 2020 to 2024 American Community Survey estimates about 523 housing units.
  • About 341 feet elevation, roughly 8 miles south of Hilo.
  • Mauna Loa lava meets Kilauea lava nearby. USGS places the southern edge of the Mauna Loa flows about a mile southeast of Keaau, where Kilauea flows begin.
  • About 154 inches of rain a year at the federal soil survey’s reference site for the Panaewa soil series, in Shipman Park next to Keaau village.
  • 8 to 20 inches of soil over pahoehoe in that same Panaewa series.
  • No county sewer. The county provides no wastewater service anywhere in Puna.
  • DOH Priority 2 area, named for Keaau, with about 9,300 cesspools.

From Ahupuaa to Sugar Town

Keaau used to be called Olaa. In 1881, W.H. Shipman and two partners bought the entire ahupuaa of Keaau, about 70,000 acres, from the estate of King Lunalilo for $20,000. In 1899 Shipman leased land to the new Olaa Sugar Company, which built a large mill in 1900. The mill ran until 1982, by then operating as Puna Sugar Company. W.H. Shipman Limited, the company he founded in 1923, still owned about 17,000 acres in Puna in 2009, and today it runs Keaau Village and the Shipman Business Park.

The company still leases out agricultural land. If your property is leased from any landowner, check what the lease says about permanent improvements before any digging starts.

The Ground Under Keaau

Keaau sits where Mauna Loa’s lava meets Kilauea’s, so what you dig into can change within a short distance. The federal soil survey uses sites near the village as reference points for two common thin soils:

  • Panaewa series (reference site in Shipman Park): volcanic ash over pahoehoe, with rock at 8 to 20 inches. Water moves moderately through the soil but very slowly through the solid rock below, except where that rock is cracked.
  • Keaukaha series (reference site about 3.5 miles southeast of the village on Highway 130): mostly organic matter with traces of ash, just 2 to 20 inches over pahoehoe, and high runoff.

Neither soil comes close to the depth a standard leach field needs. Under the state rules for fractured lava, the fix is to dig into the rock, haul in fill, and build the treatment bed in it, keeping 3 feet or more between the bed and groundwater.

Rain is the other factor. At around 154 inches a year, excavations here take on water quickly, so we plan the open-trench part of a job to be as short as we can make it.

Why the Health Department Named an Area After Keaau

In its 2017 ranking of cesspool problem areas, the Department of Health rated the Keaau area Priority 2, for potential drinking water impact. No other Hawaii Island area made that tier. The report found:

  • About 9,300 cesspools across 91 square miles, discharging about 4.9 million gallons a day.
  • The area follows a 4.3-mile-wide corridor along the groundwater flow path down Kilauea’s east slope.
  • Public water isn’t available, and many residents rely on private wells.
  • A UH study found that water can travel from the ground surface to the groundwater in as little as a fraction of an hour.
  • 25 percent of domestic wells that DOH sampled in the area tested positive for wastewater indicator bacteria.

The deadline is still January 1, 2050, the same as everywhere else. The ranking explains the stakes: in this corridor, a failing cesspool can reach someone’s drinking water fast. You can check your parcel’s rating with our priority area how-to.

Keaau in the County’s Puna Sewer Plans

Keaau shows up in almost every option in the county’s 2023 programmatic environmental study of wastewater service for Puna. One option puts a subregional treatment plant in Keaau. Another puts a single regional plant for Puna on an 18 to 20 acre Keaau parcel. Others would pipe wastewater from Keaau to the Hilo plant. The county even held the study’s public scoping meeting in the Keaau High School cafeteria.

None of these has been chosen or funded, and the study assumed construction contracts would run until about 2047. It’s fair to ask the county Department of Environmental Management what’s planned near you, but don’t build your 2050 plan around a sewer line that doesn’t exist yet.

Typical Keaau Projects

Keaau has a village core with larger lots spreading out toward the subdivisions. Common needs here:

  • Village homes on cesspools on tight lots, where the 5-foot setbacks from buildings and property lines limit where a tank can go.
  • Bedroom additions and ohana units, which can lead DOH to require an upgrade at permit time. One system serves at most five bedrooms.
  • New homes on vacant land, which need an engineered system from the start.

Logistics and Funding

Our yard is in town, so moving machines to a Keaau job is easy. The one thing we plan around is the Highway 130 junction at rush hour, when Civil Beat has reported Pahoa to Hilo commutes of up to an hour and a half.

On money, very-low-income households can ask the USDA office in Hilo whether their Keaau address qualifies for Section 504 repair help. Hawaii’s Act 204 loan program is slated to start taking applications around the end of 2026. More on our funding options page.

Where Else We Work From Keaau

See Hawaiian Paradise Park and Orchidland Estates down Highway 130, Kurtistown up Highway 11, and Panaewa toward Hilo. For the whole district, see our Puna septic services overview.

Talk to Us About Your Keaau Property

We’ll look at the lot, work with your engineer, and tell you plainly how much rock work to expect. Request a free estimate

Frequently Asked Questions

Is downtown Keaau on a county sewer line?

The county doesn’t provide wastewater service anywhere in Puna, and Keaau is in Puna. A 2023 county study looked at building a treatment plant in or serving Keaau, but nothing has been built. To check a specific property, contact the county Department of Environmental Management.

Keaau is a Priority 2 area. Does that mean I have to convert before 2050?

No. Priority 2 flags the risk to drinking water. It doesn’t shorten the 2050 timeline, though DOH can step in sooner after a bedroom addition or repeated overflows.

We drink from a private well. Should that change our plans?

It’s a good reason to act sooner. DOH found wastewater bacteria in a quarter of the domestic wells it sampled around Keaau. Ask your engineer to keep the system as far from the wellhead as the lot allows.

How deep is the soil around Keaau?

Usually not deep. The soil series mapped right by the village has 8 to 20 inches of material over pahoehoe, and a nearby series can be as thin as 2 inches. Expect rock excavation and imported fill.

Does it matter whether my house sits on Mauna Loa or Kilauea lava?

It can. USGS puts the edge of the Mauna Loa flows about a mile southeast of Keaau. Older flows generally have had more time to build soil, but every lot is different, so the engineer’s soil profile is what counts.

I lease my land. Who signs off on the septic work?

Read your lease first. Many leases require the landowner’s approval for permanent improvements like a septic system. Get any required approval in writing before the engineer submits plans.