A local pretreatment program must have four major building blocks in order to succeed. First, the POTW must have the legal authority to implement the program. This legal authority usually is based on state law and local ordinances. State law authorizes the municipality to regulate industrial users of municipal sewage systems. The municipality, in turn, establishes a local ordinance that sets forth the components of its pretreatment program and identifies a person empowered to implement the program.

The legal authority granted by state and/or local law must authorize the POTW to limit the pollution levels in discharges from industrial users of the sewage system. It must be authorized to enforce national pretreatment standards and to implement local limits in addition to or in excess of the federal standards. It also must be empowered to issue permits to industrial users, which set forth all applicable pollution control requirements. Finally, the POTW's legal authority must include the right to inspect and monitor industrial facilities without prior notice, and to take enforcement action against violators.

In addition to obtaining legal authority, the POTW must develop a comprehensive database describing its industrial discharges. An industrial waste survey is commonly used to obtain data identifying the volume and pollutant concentration of industrial effluents. This survey provides a database that allows the POTW to identify all major sources of industrial wastewater discharged to its sewage system.

A successful pretreatment program also requires adequate staffing. Personnel are required for sampling and inspection, laboratory analysis, technical assistance, legal assistance, and program administration. The resources required for each activity depend upon the size of the sewage district, the number of industrial users, and POTW policies.

The final key building block of a successful pretreatment program is funding. Funding for the program may be included in the municipal budget for the POTW or recovered through charges to the industrial facilities. These charges can be incorporated into a facility's basic fees for sewage services, or levied as a separate pretreatment charge. The size of the charges can be based on the amount of POTW services (e.g., monitoring) required by a facility, the facility's wastewater flow, or the amount of pollutants it discharges.