County Low Impact Development (LID) Outreach

1. County Low Impact Development (LID) Outreach BRIAN LEADERS, RLA REGISTERED LANDSCAPE ARCHITECT

2. Discussion Topics _______________________________________________ • What is a watershed? • Why we need a Stormwater Management Ordinance • Problems caused by not having a Plan • Urban Conservation Problems • EPA “Today” • BMP’s (Best Management Practices) • Iowa DNR

3. What is a Watershed?

4. A watershed is a geographic area from which water drains toward a common watercourse (such as a lake, stream or ocean) in a natural basin.

6. When thinking of a watershed do not just think of water, include land, landuse, topography, geology etc. All of these components affect watersheds.

7. Why do we need a Stormwater Management Ordinance?

8. This is what we are seeing now!

13. Yes this is a paved street!

14. What problems are caused by not having a Stormwater Management Plan?

15. evapotranspiration: 40-50% interflow: 20-30% surface runoff: <1% Watershed Hydrology BEFORE Development www.psat.wa.gov/Programs/LID.htm

16. Watershed Hydrology AFTER Development evapotranspiration: ~25% interflow: 0-30% surface runoff: ~30% www.psat.wa.gov/Programs/LID.htm

17. Urban Conservation Problems ___________________________________

18. Urban Conservation Problems __________________________________ 10 to 20 times higher erosion than agriculture

19. Urban Conservation Problems ___________________________________ Storm water runoff is carrying high concentration of pollutants directly into creeks, stream and river.

20. Urban Conservation Problems ___________________________________ Developing in the fragile loess soils

21. Urban Conservation Problems ___________________________________ Rural vs. urban conflicts

22. EPAand Effluent Discharge Limits

23. Effluent Limitation Guidelines(ELG’s) _______________________________________________ On December 1, 2009, the U.S. Environmental Protection Agency (EPA) released effluent limits on stormwater discharges from many construction and development sites (the Construction Rule). (74 Fed. Reg. 62,996)1

24. The Construction Rule became effective February 1, 2010, and imposes the following general requirements: _________________________________________________________________________________ • Non-numeric limitations apply to construction activity that disturbs one or more acres; • Beginning August 2, 2011, a numeric turbidity limit and related monitoring requirements will apply to construction activity that disturbs 20 or more acres at one time;

25. Numeric Turbidity _______________________________________________ 20 32 50 110 178 345 412 EPA’s Numeric Turbidity Limit is 280.

26. 3) No later than February 2, 2014, the numeric turbidity limit will apply to projects that disturbs 10 or more acres.

27. EPA’s Main Goals ______________________________________________________ • Preserve and improve water qualityon a national scale. • Reduce sediment discharged from construction sites by four billion pounds each year.

28. Effective Controls and Required BMP’s ________________________________________________________ Controls are considered Effective When: “…bare soil is uniformly and evenly covered with vegetation or other suitable materials, storm water is controlled so that rills or gullies are not visible and channels or stream banks are not eroded.

29. Selecting temporary BMP’S(Best Management Practices)for you!

30. Down Gradient Perimeter Control ________________________________________________

31. Ditch Checks _______________________________________________

32. Channel Protection _______________________________________________

33. Temporary Ponding _______________________________________________

34. Construction Phasing _______________________________________________

35. Access Protection _______________________________________________

36. Inlet Protection _______________________________________________

37. Temporary Cover & Protection _______________________________________________

38. Spoil and Stockpile Areas _______________________________________________

39. Selecting permanent BMP’S(Best Management Practices)for you!

40. Rain Garden _______________________________________________

41. Infiltration Berm _______________________________________________

42. Soil TestingInfiltration and Embankment _______________________________________________

43. Sand Filters _______________________________________________

44. Dry Detention _______________________________________________

45. Wet Detention _______________________________________________

46. Constructed Wetlands _______________________________________________

47. Grassed Swales _______________________________________________

48. Dry and Wet Swales _______________________________________________

49. Grassed Vegetated Filter Strips _______________________________________________

50. Pervious Pavement _______________________________________________