Groundbreaking and Blessing Held for New Wastewater Pilot Project in Kīhei

A blessing and groundbreaking ceremony was held on Thursday for a new wastewater pilot project on land owned by Haleakalā Ranch adjacent to the Kīhei Wastewater Reclamation Facility in South Maui.

Three new low cost, low energy, green infrastructure systems are being constructed this summer to purify water coming out of the Kīhei Wastewater Reclamation Facility. These new systems will harness the power of plants, soil and microbial activity to purify wastewater to approach drinking water standards, dramatically expanding its potential uses and reducing the need for disposal via injection wells. 

Organizers say there was one overarching message: nature-based solutions have the potential to help Maui County reach its goal of better managing and reusing its treated wastewater. 

The event was held by the nonprofit Ridge to Reefs and its partner Sunshine Vetiver Solutions, with support from Maui Nui Marine Resource Council.

“We are happy to see the progress that Maui County is making to reuse its wastewater, which is currently treated to R-1, the highest level of treatment,” said Paul Sturm, Founder and Executive Director of Ridge to Reefs. “The County is planning construction of infrastructure to bring this R-1 water to more users in the community to meet its goal of 100% wastewater reuse.”  

“While the construction of the County’s new infrastructure to expand water re-use is taking place, vetiver fields and other nature-based systems can be quickly employed to use up any excess R-1 treated water,” said Sturm. “Of the treated wastewater generated at the Kīhei Wastewater Reclamation Plant, approximately two million gallons per day is currently placed into injection wells. By using drip and overhead irrigation to run treated wastewater through fields of vetiver – a very thirsty plant — there will be less wastewater to dispose of and less need for disposal through injection wells.” 

The blessing ceremony was led by Kimokeo Kapahulehua and included the planting and blessing of native plants and groundbreaking.

Sturm estimates that less than 60 acres of vetiver, grown around the County Wastewater Reclamation Facility in Kīhei or its current distribution lines, could handle the two million gallons of treated wastewater per day that is currently placed into injection wells. 

“Vetiver is a clumping, non-reproducing plant that has been used in Hawaiʻi for 30 years to control erosion and runoff,” reported John Astilla, a Maui-based farmer and owner of Sunshine Vetiver Solutions. “It is sterile, meaning it can’t reproduce or spread and has the lowest rating possible on a scale that rates how likely plants are to become invasive. It’s fast growing, long-lived and has a high evapotranspiration rate, making it an ideal choice for handling wastewater.” 

Sturm explained that Ridge to Reefs’ other nature-based systems, including denitrifying bioreactors made with wood chips, biochar and sand, can also help improve the quality of treated wastewater, by removing nitrogen, phosphorous and residual pharmaceuticals. This will help expand the potential for the treated wastewater to be used on food crops at local farms.

A modified Soil Aquifer Treatment basin will also be built on the site, which will work in combination with a denitrying bioreactor and vetiver, to create a system that removes the majority of reef-harming nitrogen from treated wastewater. 

In addition to sharing their plans at the groundbreaking, Sturm and Astilla presented their nature-based solutions to handle treated wastewater on a special Zoom presentation hosted on Wednesday evening by Maui Nui Marine Resource Council as part of its monthly “Know Your Ocean Speaker Series.” The presentation can be viewed on Maui Nui Marine Resource Council’s Facebook page at www.facebook.com/MNMRC

Among those in attendance at the groundbreaking event were Maui Mayor Michael Victorino, State Senator Rosalyn Baker, State Representative Tina Wildberger, and Maui County Councilmembers Shane Sinenci, Kelly King and Mike Molina. Councilmember Yuki Lei Sugimura also toured the site. 

Ridge to Reefs is a nonprofit 501(c)(3) formed in 2011 to help protect and restore coastal and coral reef ecosystems by reducing land-to-sea pollution with green infrastructure. The organization uses natural methods and innovative engineering to solve pressing environmental and social problems.