In order to comply with more stringent regulations and our mission of collecting and treating wastewater in a reliable, cost-effective and environmentally responsible manner, the GMWC has developed updated sanitary and combined sewer guidelines. These guidelines set concentration limits for substances that represent a risk for the environment and GMWC treatment processes. It also lists substances that should be prohibited of discharge to sewer systems.

To develop these guidelines the following considerations have been taken into account:

  • Effluent Discharge Objectives
  • Treatment plant processes
  • Biosolids reuse (compost production)
  • Historical information on local industrial, commercial and institutional users
  • CCME Model Sewer Use Bylaw guidance document

There are numerous emerging substances that are not addressed in the GMWC guidelines because scientific information and technological options to address these substances are not yet well established. GMWC will continue to regularly update its guidelines based on the availability of new technology and scientific knowledge.

GMWC provides these guidelines to its partner municipalities for enforcement through their sewer by-laws.

Please verify with your respective municipality to confirm applicable by-laws and product acceptability for discharge within the municipal sewer system.