Nature Water, Published online: 11 June 2026; doi:10.1038/s44221-026-00660-7 Wastewater-based epidemiology has been proposed as a faster, near real-time window into community substance use, but national-scale implementation in the United States has been elusive. A National Institute on Drug Abuse-funded pilot with Biobot Analytics spanning 76 sites across 41 states demonstrates that harmonized, near-real-time wastewater surveillance of opioids and adulterants is not only feasible but actionable,