Maui Nui Marine Resource Council holds July 6 talk on nature-based solutions to cesspools

Part of Maui Nui Marine Resource Council’s monthly series, a free Zoom webinar called “Nature Based Solutions to Cesspools and Injection Wells — Latest Findings from Field Research” will be held at 5:30 p.m. Wednesday, July 6.

Are there effective nature-based solutions that can help replace the 90,000 cesspools in the State of Hawaiʻi that are currently releasing nearly 53 million gallons of raw, untreated human waste into the environment each day?  

Can nature-based methods also provide quick-to-install alternatives to the injection wells located throughout the state that are used for wastewater disposal, often to the detriment of nearshore ocean waters and coral reefs?   

Those questions and more will be answered by presenters Paul Sturm, founder and executive director of the nonprofit organization Ridge to Reefs, and John Astilla, a local farmer and founder/owner of Sunshine Vetiver Solutions, a news release said. 

Admission is free, but advance reservations are required. To reserve a spot, click here.

The presentation is part of Maui Nui Marine Resource Council’s monthly Know Your Ocean Speaker Series, supported by the County of Maui.

Sturm will discuss a nature-based treatment system for cesspool conversion, which has been shown to be highly effective in six months of testing with University of Hawaiʻi. It relies on native plant and restoration plant species that use evapotranspiration to reduce the concentration and volume of effluent released to the environment and functions as a zero discharge system. 

Astilla and Sturm will also discuss the results of a pilot project adjacent to the Kīhei wastewater plant that demonstrates an alternative to injection wells that is less costly, highly effective and more space efficient.

This pilot project demonstrates techniques that can be used to treat effluent from any of Maui’s three wastewater plants. 

Cesspools are little more than holes in the ground that discharge raw, untreated human waste into the environment, where it finds its way into groundwater drinking supplies, rivers and the ocean.

There are about 12,000 cesspools on Maui and 1,400 on Molokaʻi.

In 2017, the Hawai‘i State Legislature passed Act 125, which mandates that by January 1, 2050, all cesspools in the State, unless granted exemption, shall upgrade or convert to a septic or aerobic treatment unit, or connect to a sewer system (Act 125, 2017). 

But replacing a cesspool with an approved septic system requires a significant cash outlay for most homeowners, with an average cost of more than $23,000 per cesspool replacement.

“More than 53 million gallons of human sewage enters Hawaii’s environment each day through cesspools; this sewage contaminates groundwater drinking water supplies and our coastal ocean waters, creating algae blooms and harm to corals,” Sturm said. “That’s why Ridge to Reefs has focused on finding affordable nature-based alternatives to cesspools, to ease the financial burden on homeowners and businesses, and provide a solution to this pollution issue.” 

Sturm and Astilla will also be describing an affordable, nature-based methods to replace the use of injection wells to re-use or dispose of treated wastewater.

These methods have been tested at a pilot site near the Kihei Wastewater Reclamation Facility. Results of this pilot project will be presented during the Zoom webinar.

“Throughout the state of Hawaii, more than 500 injection wells, most of which were dedicated to the disposal of treated sewage effluent, had been installed by 1985,” Sturm said. “Unfortunately, this effluent has been found to enter our coastal waters, where it contributes to coral reef deterioration.”