Requires DEP to designate municipalities with critical headwaters as headwater guardians.

This bill requires New Jersey's Department of Environmental Protection (DEP) to identify and designate municipalities with critical headwaters - sources supplying drinking water to at least 1 million residents - as "headwater guardians" within one year of the bill's effective date. The DEP must develop a process using scientific data (e.g., water quality, watershed significance) to determine qualifying headwaters, then designate affected municipalities and publish the list online. Within six months of designation, the DEP must assess if environmental protections (like enhanced stormwater management or riparian buffers) are needed to safeguard water quality, subject to a 30-day public comment period. The bill mandates annual reports tracking designations, protections, and outcomes like reduced pollution or preserved buffers, while recognizing headwater guardianship as a planning factor in local land use decisions.