Incineration Toilet Could Solve Cesspool Problem

Courtesy of HIMB

The first incineration toilet is now in operation the Moku o Loʻe (Coconut Island) at the University of Hawaiʻi at Mānoa’s Hawaiʻi Institute of Marine Biology (HIMB).

Toilet, which doesn’t use water and produces no sewage, could help in reducing or eliminating cesspools. The toilet uses a small amount of energy from propane gas to incinerate both liquids and solids and produces pathogen-free, odorless ash that can be disposed of in the trash or used as a soil amendment in gardens or compost piles.

“We know that water is precious and scarce in Hawaiʻi and we really want to conserve water whenever we can,” said Judy Lemus, interim director at HIMB. “So as a conservation-based research institution we’re very interested in identifying sustainable solutions.”

HIMB is connected to municipal water, sewer and electricity services on Oʻahu through high-density polyethylene conduits that run underneath Kāneʻohe Bay. While cesspools are not the issue, resources are limited and utilities are expensive.

“The incineration toilet adds an environmentally sustainable bathroom on island for employees and visitors in a high traffic location where there were previously no facilities,” officials stated.

The self-contained system does not require connections to municipal water, sewer, or electrical infrastructure.

“They look exactly like a regular toilet, and they can burn both solid and liquid waste and they’re excellent for areas in which you don’t have any other municipal connections,” Lemus said.

The toilet can handle four uses per hour and the ash container only needs to be emptied once per week. HIMB estimates that the five-gallon propane tank will last for 120–150 uses.

There are an estimated 88,000 cesspools in Hawaiʻi, the highest number per capita in the country, that discharge more than 53 million gallons of raw sewage each day, according to the Hawaiʻi Department of Health Wastewater Branch.

We really need to protect our resources in Hawaiʻi and so a solution like the incinerator toilet is a great alternative,” Lemus said.

The Hawaiʻi Department of Health is requiring that all cesspools are upgraded, converted, or closed by Jan. 1, 2050.

The project is a collaboration between HIMB, Wastewater Alternatives and Innovations and Cinderella Eco Group. Lemus helped facilitate the project.