Perca utilizes earthworms for eco-friendly wastewater treatment solution
Perca, Inc., an environmental technology firm, has developed a solution for water regeneration that uses earthworms and microbial communities to clean wastewater naturally.
"Nature has been cleaning water since the beginning of time," said Russ Davis, Perca's president and CEO, in a press release. "We have simply created a scalable way to focus and optimize those natural processes using vermiculture, biology and sustainable principles. What's exciting to us is how effective, robust and economical the system is - even for contaminants that are notoriously difficult to remove."
The company’s vermifiltration design mimics natural processes to remove pollutants from wastewater and stormwater including BOD, TSS, nitrogen and phosphorous as well as certain metals and toxic chemicals such as polychlorinated biphenyls (PCBs) and deicers.
According to a press release, Davis stated that the technology has consistently achieved reductions of over 95% for some pollutants.
Applying the technology
Two projects in Walla Walla, Washington, have highlighted the worms' capabilities and potential – one in collaboration with the City of Walla Walla, and the other as a pilot with the Washington State Penitentiary.
"We had a significant wastewater generator that had been struggling with compliance on some difficult constituents and as a result, had been out of compliance for some time,” said Environmental Engineer for the city of Walla Walla Leah Rohan in a press release. “The solution that finally got them back into full compliance was the worm bed."
The City of Walla Walla's largest wastewater discharger is the Washington State Penitentiary. Not long ago, the Penitentiary was made aware that its wastewater contained some potentially toxic chemicals.
"Our numbers were - and still are - fairly low, but we don't want to find ourselves out of compliance," said Dean Smith, environmental specialist with the Washington State Department of Corrections, in a press release. "We had heard about Perca's system and decided to run a trial."
According to Smith in a press release, after a three-month trial the worms delivered the results as promised. Perca has provided the Washington Department of Corrections with a proposal for a full-scale system and the parties expect to talk more in 2025.
Future treatment
"Chemicals like PCBs, PFAS (per- and polyfluoroalkyl substances) and 6PPD-q (a tire preservative) are known toxic chemicals that can bioaccumulate in humans and animal tissue," Davis said in a press release. "We know that if we can remove these chemicals where they are concentrated – frequently in wastewater and stormwater – we can keep them from finding their way into the food chain via streams, rivers and groundwater."
According to a press release, Perca's vermifiltration system is scalable, making it suitable for a range of applications, from larger municipal and industrial wastewater treatment to smaller-scale operations. The company offers mobile test units to prove on-site efficacy and is expanding into other regions where chemical contamination of wastewater is an increasing concern