Amends GS 143-214.5 by prohibiting the Environmental Management Commission (EMC) and local governments implementing a water supply watershed protection program from applying impervious surface restrictions to the redevelopment of property when the redevelopment includes installation of a system for the collection, treatment, and discharge of stormwater runoff from both existing and redeveloped areas in a way that complies with all applicable stormwater management requirements. Requires the EMC to adopt rules and for local governments to amend their ordinances and local programs to implement this act's requirements. Applies to applications for permits and other approvals received on or after October 1, 2021.

Amends GS 160D-403 as follows. The statute prohibits deviations from an application or development approval after a development approval has been issued until written approval has been obtained, and sets out the process for reviewing and approving any major modification of the approval. Adds that a developer expanding the footprint of buildings approved in the original development agreement by up to 20% is not considered a major modification if the agreement has been completed within the last 15 years and there has been no change in the property's permitted use. Requires local governments to amend their ordinances and local programs to implement this section's requirements. Applies to applications for permits and other approvals received by the local governments on or after October 1, 2021.