CREW Carbon and Isometric today announced the first-ever verified delivery of Wastewater Alkalinity Enhancement (WAE) carbon removal credits. The 104.4 credits—supplied by CREW Carbon, verified by Isometric, and delivered to Frontier—demonstrate the potential of WAE as a highly scalable climate solution that is low-cost, easy to implement, and highly measurable.
The credits correspond to CREW’s WAE project in New Haven, Connecticut—soon to be one of the largest CDR projects on the East Coast of the U.S. The project is integrated into the East Shore Water Pollution Abatement Facility, which processes 40 million gallons of wastewater per day, and aims to remove thousands of tonnes of carbon dioxide from the atmosphere in 2025.
CDR must scale dramatically to meet global climate goals and WAE is one of the most promising pathways. It integrates with existing infrastructure, leverages existing permits, and utilizes one of the lowest cost and most abundant minerals on earth—limestone. CREW’s project development process takes wastewater treatment facilities from initial assessment to full WAE operations in just three months, with minimal modifications. CREW’s process also stabilizes key environmental conditions for the wastewater treatment process. This lowers the cost of wastewater treatment, reduces pollutant levels in the treated water and makes the entire process more effective and efficient.
With nearly 110,000 municipal wastewater treatment facilities worldwide—including over 16,000 in the United States—WAE presents a vast, untapped opportunity to significantly enhance carbon removal efforts. Estimates suggest that WAE could scale to remove 500 million tonnes of carbon dioxide annually, making wastewater treatment plants pivotal players in climate mitigation.
Dr. Joachim Katchinoff, Co-Founder and CEO of CREW Carbon, said:
“Utilizing existing infrastructure and proven science, CREW’s technology offers a cost-effective, highly measurable and globally scalable approach to durable carbon removal. CREW’s Wastewater Alkalinity Enhancement integrates into existing infrastructure to transform everyday facilities into climate assets—delivering durable, measurable carbon removal while improving treatment efficiency, lowering costs, and helping operators protect the local environment. This delivery proves that carbon removal is already happening at scale.”
How WAE works
In wastewater treatment, microbes break down organic waste, releasing carbon dioxide that would typically enter the atmosphere. WAE enhances this process by introducing finely crushed, soluble alkaline materials—such as limestone—during treatment. These materials react with carbon dioxide, converting it into stable bicarbonate ions, which remain in the treated wastewater and are ultimately transported to the ocean. The ocean, the world’s largest carbon sink, safely stores these bicarbonate molecules for thousands of years, removing the carbon from the atmosphere.
WAE can also lower operational costs for wastewater treatment facilities by replacing carbon-intensive and hazardous pH control chemicals with locally sourced, natural minerals.
Setting the standard for WAE credits
These credits were certified according to Isometric’s industry-first Wastewater Alkalinity Enhancement Protocol, which takes a rigorous, science-based approach to monitoring, reporting and verification (MRV). The protocol accounts for potential downstream losses—where some of the captured carbon dioxide may be released into the atmosphere—using peer-reviewed river and ocean chemistry models, tailored to each site’s specific conditions.
“The world’s first verified WAE credits set the benchmark for the pathway. Isometric’s scientific rigor and transparency means that buyers can be confident that every WAE credit issued by Isometric represents one tonne of carbon dioxide permanently removed from the atmosphere,” said Eamon Jubbawy, Founder and CEO of Isometric.
A major step forward for CDR
This delivery marks the first fulfillment under CREW Carbon’s $32.1 million offtake agreement with Frontier buyers for 71,878-tonnes of CDR, between 2025 to 2030.
“Just four months after signing a Frontier offtake, the CREW team has delivered the first-ever tons for wastewater alkalinity enhancement. This quick-out-the-gates delivery shows how CREW can leverage existing infrastructure to deliver tons fast,” said Hannah Bebbington, Head of Deployment at Frontier.
Buyers, suppliers, and policymakers can access detailed, transparent data for every WAE credit on the Isometric Registry, ensuring complete visibility and scientific accountability.
As the demand for high-quality carbon removal solutions grows, this milestone underscores WAE’s potential to become a key component in global climate strategies—leveraging wastewater treatment plants not just as pollution management systems, but as critical climate assets.
