1. Building Green in Bowling Green
Construction Site
Stormwater Management
Barry Tonning Tetra Tech

2. State and local rules require:
Local and state permit coverage
SWPPP available for review
BMPs in the field that match the SWPPP
Contractors’ weekly inspection forms available for review

3. Minimizing the active construction area

7. Consistency between what’s in the SWPPP and BMPs installed in the field
Site Drainage Plan
Site Building Plan
Site Grading Plan
Existing Site Conditions
Final Site Land-scaping Plan
Stormwater Pollution Prevention Plan

8. SWPPP Applicability, Preparation, Contents, and Process for Amending
SWPPP applies to the site AND offsite borrow/disposal areas
SWPPP is prepared BEFORE filing the NOI and beginning work
SWPPP describes site, pollutants at site, plan for controlling pollutant discharges, construction procedure, & responsible parties
SWPPP is amended by site personnel or project engineer as construction proceeds on an as-needed basis

9. Basic SWPPP outline Site description & map
Description of receiving waters
Description of construction project
Identification of pollutants, sources, and any non-stormwater discharges
Erosion & sediment controls
Controls for other pollutants
Procedures for inspections, BMP maintenance, and recordkeeping
Certification & signatures

10. Building, stabilizing, and preserving the drainage system (ditches, traps, ponds)

11. Drainage system controls
Inlets for storm drains and channels
Pond up the runoff to settle & filter it
Use rock berms, rock bags, or other items
Storm drain & channel outlets
Protect areas receiving discharge flows from erosion caused by flow velocities
Use rock or turf reinforcement mats; seed heavily
Ditches – convey water without eroding
Traps – pond and settle out muddy runoff

12. Good application of silt fence and rock bags for inlet protection – Lots of options available

13. Other inlet protection approaches

14. Outlet Protection

15. Drainage ditch liner materials
Steep or high flow channels (> 20%)
Use concrete or riprap
Moderately steep channels (~ 10%)
Use riprap or turf mats & seeding
Slightly sloping channels (~5%)
Use turf mats or blankets & seeding
Mostly flat channels (~2%)
Use seeding with blankets
Seed ditches immediately after construction
Triple the seeding rate

17. Sediment traps & basins
Designed & placed to pool runoff so sediment can settle out
Installed before grading/fill work begins!
Seeded immediately after construction
Located in swales or low-lying areas where flows are concentrated
Should not be placed near flowing streams
Outlets should be made of rock or pipe

18. Rock filter as sediment trap

19. Good siting & installation of sediment traps

20. Protecting riser during construction. Wrap with filter fabric
Protecting riser during construction! * Wrap with filter fabric * Use rock inlet dam * Pile #57s around pipe

22. Buffer zone requirements
25 ft undisturbed buffer between disturbed areas and bankfull elevation of high quality waters / impaired waters
50 buffer required between sediment-impaired waters with no TMDL and disturbed areas
Dredge/fill areas,
stream crossings,
or other deviations
require “adequately
protective” alternate
practices, explained
in SWPPP

23. Buffer Zone
Edge of Receiving Water is defined as bankfull elevation of a water of the Commonwealth

24. Slope stabilization

25. Slope protection basics
Seed and mulch immediately after grading
Divert upland runoff with berms or channels
Tread-track or terrace highly erodible soils
Install sediment barriers at toe of slope and at correct spacing on long slopes
Use blankets, mats, or mulch on steep slopes
Control runoff from upland areas with drain pipes or lined downdrain channels

26. Mass grading tips
Install all downgradient silt fences, traps, basins before clearing & grubbing
Use grubbed-out debris as sediment barriers / berms downhill from your work
Use soil stockpiles as sediment berms / traps that intercept concentrated/sheet flow
Seed and mulch/blanket/mat your ditches and slopes as soon as you build them

27. Blankets and mats (rolled erosion control products)
Excellent for slope and channel protection
Use blankets for slopes flatter than 3:1 and channels flatter than 20:1
Use mats for slopes greater than 3:1 and channels steeper than 20:1
KY TC requires blankets in all channels & slopes > 4:1

28. Wishful thinking . . .
Silt Fence cannot handle large flows. This site needs erosion control or additional rows of silt fence.

29. Stabilization requirements
Temporary stabilization required on portions of the site where construction activities have temporarily ceased shall be initiated within 14 days
Final stabilization also required within 14 days after permanently ceasing work
Final stabilization required if work is suspended for more than 180 days

30. Homebuilder lot BMP compliance

32. Effective best management practice applied to the maximum extent practicable?
Passable practice that’s OK?
Practice needs improvement, compliance assistance?
Practice fails, cause for a notice of violation of water quality ordinance?
I would need to see this first hand for more information.
Your Comments:

35. Fiber roll installation

36. Good housekeeping & pollution prevention

37. Good housekeeping Mud tracking on roadways
Fuel, oil, paint, hazardous waste mgmt
Concrete washout sites
Trash & debris management
Sewage management
Dust control (if needed)

38. Waste management
Provide convenient, well-maintained toilet facilities

40. Establish proper building material handling and storage areas
Building materials with runoff potential should be stored indoors or under cover

41. Designate concrete washout areas Or wash out material in formed-up areas ready for the next pour

44. Establish proper equipment/vehicle fueling and maintenance practices
Your on-site fueling and maintenance area should have a spill kit
Conduct vehicle fueling and maintenance activities in areas away from ditches
Conduct maintenance on vehicles and equipment off-site if possible

45. Develop a spill prevention and response plan
Note the locations of chemical storage areas, storm drains, ditches, and surface waters
Specify how to notify appropriate authorities
Describe the procedures for spill cleanup
Identify personnel responsible for implementing the plan

46. The Good, The Bad, and the Ugly
The Good – stabilized exit pads, initial silt fence installation, initial inlet protection
The Bad – temporary seeding/mulching, silt fence maintenance, inlet maintenance, waste and materials management
The Ugly – ditch and channel protection, some homebuilder lots

47. Fair construction entrance; poor silt fence

48. Good fence, needs seed/mulch

49. Good inlet protection

50. Good stabilization on pipe job

51. Well vegetated sediment basin, with poorly vegetated inactive area in foreground

52. Poor vegetation and no sign of active grading

53. Unstabilized slope

54. Lot with poor vegetation and poor silt fencing

55. Lack of inlet maintenance and sediment management

56. Poor stabilization & drainage management
Left – northwest corner discharge location, showing sediment in discharge.
Right – stopped up curb inlet (lower middle) with pooled water. No grading occurring in this area.

57. Eroding, unstabilized drainage swale

58. Poor site stabilization, drainage system, and sediment trap construction & maintenance

59. Overflowing concrete washout

60. Vacant inactive site with poorly installed silt fence and poor vegetation

61. Poor soil stabilization, shaky silt fence, ineffective inlet protection

62. Torn and frayed

63. Poor site management