In 1987, the EPA was required under Section 402 (p) of the Clean Water Act (N40CFR Part 112.26) to establish final regulations governing stormwater discharge permit application requirements. In 1990, the Federal Register indicated that the Palm Beach County area was to begin compliance with the program. In 1997, the first 5-year permit was issued to Palm Beach County's forty co-permittees. In November 2002, the second term permit was issued. In March 2011, the third term permit was issued.

Palm Beach County MS4 permittees have taken a cooperative approach to permit compliance, jointly conducting several permit activities and collectively developing a number of tools used to carry out the permit programs. Each permit term, the lead permittee (Northern Palm Beach County Improvement District (NPBCID)) enters into inter-local agreements with each of the remaining permittees to oversee the joint activities. A Steering Committee, composed of individuals representing different permittees, advises NPBCID. Mock#8226;Roos acts as staff to the Steering Committee, assisting with administration of the joint activities.