What is the difference between the storm drain system and the sanitary sewer?

Storm drain systems include the gutter, drainage inlets, catch basins, piping and the waterways they convey storm water to in order to prevent flooding of our streets.  Stormwater flows through these conveyances directly to receiving waterbodies such as the Delta and Bay without being treated. Storm drain systems are also often referred to as MS4s or Municipal Separate Storm Sewer Systems. Sanitary sewers transfer wastewater from our homes and businesses to wastewater treatment plants for primary, secondary or tertiary treatment prior to being discharged to receiving waterbodies via outfall pipes or reclaimed for irrigation purposes.

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1. How do I calculate the Flood Control flow data point? Do I need to know the post development design flows for my project?
2. How do I determine the 25-year 24-hour storm depth
3. What are Pollutants of Concern (POCs)?
4. What are Stormwater Best Management Practices (BMPs)?
5. What is a Watershed?
6. What is an illicit discharge and who do I call to report it?
7. What is an NOI and what permits does it cover?
8. What is C.3?
9. What is NPDES and who oversees it?
10. What is the design storm for my project?
11. What is the difference between a Stormwater Pollution Prevention Plan (SWPPP) and a Stormwater Control Plan (SWCP)?
12. What is the difference between point source and non-point source?
13. What is the difference between the County Watershed Program and the Contra Costa Clean Water Program?
14. What is the difference between the storm drain system and the sanitary sewer?
15. What is the drainage easement across my property? Can I build on it? What can I do on it?
16. Who do I contact if I have flooding on my street?