- water
- infrastructure
A publicly owned treatment works is the Clean Water Act's name for a municipally owned WWTP and its collection system. The label matters because a POTW carries obligations a private plant does not: it must administer a pretreatment program that limits what industrial users may send to the sewer, and it discharges its own treated effluent under a municipal NPDES permit.
For the platform, the POTW distinction sorts a discharger by who runs it. A hyperscale campus that routes cooling blowdown or sanitary flow to the local POTW becomes an industrial user inside that public permit for that stream rather than a permittee in its own right — which changes where the monitoring record lives and who is accountable for an exceedance. Any separate direct discharge, stormwater, or other regulated source at the same campus can still require its own facility-specific permit.