Treatment Works Approval (TWA)

A Treatment Works Approval (TWA) from the NJDEP Division of Water Quality and the Stoney Brook Regional Sewerage Authority (SBRSA) is required prior to construction of a proposed sewer extension. Sewer extensions are defined as:

  • A sewer that extends along a roadway, along a public right-of-way, or along an easement through more than two properties 
  • A sewer that conveys flows from more than two buildings
  • A sewer that conveys, or will convey, 8,000 gallons per day or more of sewage.

Additionally, a TWA from the SBRSA is required prior to construction of a proposed sewer or development that will convey or produce 2,000 gallons per day or more of sewage. If the proposed sewer does not meet the definition of a sewer extension, it will not require NJDEP approval.

All TWAs must be reviewed and approved by the Sewer Department before they are submitted to the SBRSA or NJDEP. The SBRSA and the NJDEP will not accept TWAs that have not received Department approval.

Sewer extensions and sewers that will convey 2,000 gallons per day or more must be designed in accordance with Chapter 34 of the Princeton Municipal Code, N.J.A.C. 7:14A-22 and 23, and the requirements of the TWA application. More information can be found on the Division of Water Quality’s website.