NACWA Supports Colorado Variance in Critical CWA/SDWA Nexus Issue

(January 22, 2020) –NACWA submitted comments last week in support of EPA approving a short-term variance under the Safe Drinking Water Act (SDWA) for Denver Water to comply with a negotiated Lead Reduction Program Plan (LRPP). The LRPP allows Denver Water to follow a more flexible corrosion control treatment process of alkalinity and pH adjustments, along with a 15-year replacement plan to replace lead service lines, rather than requiring the drinking water utility to follow a one-size-fits-all approach of straight orthophosphate dosing that would have significant nutrient impacts on downstream water quality and NACWA member clean water utilities.

EPA recognizes that the LRPP components in the variance are “expected to provide equivalent or better public health benefits compared to what would be achieved using orthophosphate treatment.” This flexibility embodies EPA’s recognition of the intersection of the SDWA and the Clean Water Act (CWA) in a holistic, one water framework that protects public health and the environment.

This is one of the first times nationally that state and federal regulators have had to address potential consequences where increased use of orthophosphate for lead reduction can create unintended – but very real – challenges for downstream wastewater treatment facilities and related impacts on water quality.  However, this type of situation is likely to become more common as EPA’s proposed Lead and Copper Rule encourages the use of orthophosphates as a preferred method for corrosion control technology (CCT). Hopefully this variance, which was supported by both the impacted drinking water and clean water utilities, will provide a model for how to address these concerns going forward.    

NACWA applauds Association member utility the Metro Wastewater Reclamation District in its role as a downstream stakeholder and its dedication to finding a workable solution to the problem. This positive outcome is the result of tremendous expert stakeholder input and collaboration that demonstrates a flexible approach that is both protective of public health and downstream water quality.

Please contact Emily Remmel, NACWA’s Director of Regulatory Affairs, with any questions or to discuss further.