New California Construction General Permit

New Best Management Practices Requirements

The new Construction General Permit went into effect on September 1, 2023. 

Below, we are looking at changes to the Best Management Practices (BMP). 

BMP Changes:

1. Passive Treatment is the application of natural or synthetic chemicals and products to reduce turbidity in discharges. The new permit details specific treatment technology requirements.
2. Construction Dewatering Discharges not covered under a separate permit must follow Attachment J of the General Permit. The Water Board also clarified that dewatering does include pumping storm water that has collected in trenches and low spots on the construction site.
3. Preserving topsoil is now a mandatory minimum BMP.
4. Additional Sediment Controls for Risk Level 2 and 3 projects including changes to slope requirements, linear sediment controls on slopes, and mandatory surface water buffers when a water of the US is located within 50 feet of the Site’s earth disturbances.
5. Erosion Control requirements are more prescriptive.

All of these requirements will be detailed in the project-specific Storm Water Pollution Prevention Plan but will require more attention to detail to ensure the project is meeting the requirements of the general permit. 

If you have any questions about the upcoming Construction General Permit, please reach out to Associates Environmental’s Jennifer Fieber, (714) 916-4996.