Why Unknown Service Lines Can Become A Massive Compliance Problem

Kristin Epstein, Lead and Copper Rule Compliance Coordinator for CDM Smith, explains that under the Lead and Copper Rule Improvements (LCRI), unknown service lines are effectively treated as potential lead service lines until proven otherwise. While utilities can remain compliant with unknowns in their inventories, those unknowns are included in the calculation used to establish future replacement obligations. Epstein emphasizes that failing to reduce unknown service lines before the November 2027 compliance deadline can significantly increase a utility's required annual replacement rate and create long-term implementation challenges.