If a treatment plant fails to meet its NJPDES discharge permit limits, it can adversely impact the waterway it discharges into, threatening drinking water supplies and the habitat of aquatic plants and animals. To prevent further harm, a sewer ban is implemented in the areas served by the affected treatment plant. This measure protects the receiving water from additional damage until the problem can be corrected. To avert the need for a sewer ban, the Capacity Assurance Program serves as a planning tool which is implemented when committed flows (anticipated flow from permitted projects not yet constructed) reach 80% of a treatment plant's permitted design capacity. This helps treatment plant owners decide how a plant's remaining flow capacity will be used and whether an equipment upgrade is necessary to assure future capacity.

The Sewer Ban Program and Capacity Assurance Program are the responsibility of the Bureau of Financing and Construction Permits.