What is an impervious surface?
Impervious surface means those disturbed or hard surfaced areas that either prevent or retard the natural entry of water into the soil. Rooftops, buildings, streets, parking lots, sidewalks, asphalt, concrete, other paving, driveways, patios, artificial turf and storage areas are all examples of impervious surfaces. These improvements effect natural infiltration, creates more runoff, increases the rate of runoff and alters runoff patterns of stormwater that drains from an area.

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1. What is the National Pollutant Discharge Elimination System (NPDES) Stormwater Program?
2. What is a Municipal Separate Storm Sewer System (MS4)?
3. Which Municipal Separate Storm Sewer Systems are regulated by the Eastern Washington Phase II Municipal Stormwater Permit?
4. How are the regional stormwater utility service areas determined?
5. What is stormwater and why is it a problem?
6. What is an impervious surface?
7. How will the stormwater management program benefit taxpayers, homeowners, etc.?
8. What kinds of pollutants are found in the storm drain system?
9. Are sewers and storm drains the same thing?
10. What can residents do to help improve stormwater quality?
11. What can you put down the storm drain?
12. What happens if the Regional Stormwater group does not comply with its NPDES stormwater discharge permit?
13. What is meant by a "larger common plan of development or sale?"
14. What kinds of stormwater discharges are required to have NPDES stormwater permit coverage?
15. What is the stormwater fee used for?
16. How is the stormwater fee calculated?
17. Is the utility fee just another tax?
18. Why a stormwater utility now?
19. No water runs off my property. Why am I being charged a stormwater fee?