Snapfinger Creek. Raymond J. Wilke, P.E. Engineer of Record

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1 Snapfinger Creek Paul E. Simpson, P.E. GeoRay, Inc. Raymond J. Wilke, P.E. Engineer of Record

2 The Project Team City of Pine Lake Dekalb County GeoRay Willmer Engineering Register-Nelson GEFA Ga DNR USACOE

3 Upper Wetlands Runoff Pollutants scsts

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5 Timeline 2005 Watershed studies ID Snapfinger Creek Issues 2007 City constructs first wetlands along creek 2008 Obtains 319h grant to improve upstream wetlands, provides pre-treatment of flows to Lake 2009 GeoRay engaged to design project 2010 construction of 0.8 ac lower (west) wetlands in floodplain (Phase 1), treats runoff, Lake discharges 2010 Balance of project to bid 2010 Application to GEFA for ARRA funding 2011 GEFA loan for $1,500,000 approved 2012 Project completed

6 About the Project at Pine Lake Goal: Protect and Improve water quality, habitat, biology Methods: infiltration trench, bioretention of run-on, natural channel design, streambank stabilization, lake sediments removal, & constructed wetlands

7 About Snapfinger Creek Watershed Improvement Plan ID s TMDL s Fecal Coliform, Bio M County STEP Laterals/Creek crossings Parallel Trunk Sewer Lines

8 Water Quality Data

9 Table 6-2. Summary of TMDL Allocation for DeKalb County Fecal Coliform-Listed Streams Stream Segment Current Load (counts/ 30 days) WLA (counts/ 30 days) WLAsw (counts/ 30 days) LA (counts/ 30 days) MOS (counts/ 30 days) TMDL (counts/ 30 days) Percent Required Reduction Arrow Creek Ball Mill Creek Bubbling Creek 6.87E E E E E Burnt Fork Creek Lullwater Creek Nancy Creek North Fork Peachtree Creek 2.49E E E E E E E E E E E E E E E Peavine Creek 3.45E E E E E South Fork Peachtree Creek Camp Creek Cobbs Creek Conley Creek Doolittle Creek Honey Creek Intrenchment Creek Shoal Creek Snapfinger Creek South River, Atlanta to Flakes Mill Rd 2.70E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E South River, Flakes Mill Rd to Pole Bridge Creek 6.89E E E E E E E E E E Sugar Creek Swift Creek Yellow River Doless 2.45E E E E E Creek Little Stone Mountain Creek 3.52E E E E E E E E E E Stone Mountain Creek 7.16E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E

10 Funding GEFA Loan Recipient: City of Pine Lake Item Total CWSRF Loan Construction $ 1,300,000 $ 1,300,000 Contingency $ 125,000 $ 125,000 Engineering & Inspection $ 150,000 $ 150,000 Administrative/Legal $ 50,000 $ 50,000 TOTAL $ 1,625,000 $ 1,625,000 City will be charged a 2% closing fee of $32,500

11 Costs Original Construction Bid $689,991 Owner Requested Changes/Adds $302,947 Field Engineering, Const Administration $129,735 Landscaping, Trail & Park Amenities $157,281 Total $ 1,279,954

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13 TMDL s Fecal Coliform Water Quality

14 Funding Sources City Dekalb GEFA

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16 Schematic Design

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18 Berm Lake Considerations Streambank

19 Geotech Borings

20 Berm Considerations Large Trees Aesthetics, Pedestrian Trail Fishing access Unknown/questionable fill (1920 s construction) Plugged outlet works No emergency spillway

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22 Streambank Considerations Scallops Benching Parallel trunk sewer Sewer easement Strip of City-owned land adjacent to creek

23 Flood Map

24 Lake Considerations 12.1 Acres Dredging of 13,500 cy accumulated sediments Improve habitat Trees on dam providing a lot of shade fish friendly Slope of beach and swimming area depth Ability to isolate swimming area New outlet works Ability to discharge to wetlands or creek Able to feed wetlands during dry periods

25 Geotechnical Redundant Flows Multiple Treatment Options BioRetention Dredging Permitting

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27 Infiltration Trench Section at Bioretention

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29 Paul E. Simpson, P.E. Brain J. Rainwater, P.E.

30 What did it take to get to here?

31 Existing Conditions

32 Scour & Washout

33 Bank Scour

34 Beaver Damage

35 Downstream Conditions

36 Full Pool

37 Draining the Lake

38 Inside the Swimming Area

39 Almost There

40 More Draining

41 Wildlife

42 Grass Carp + Low Water = Turtle Dinner

43 Canadian Geese

44 Other Wildlife

45 Surveying for Base Topography in Dry(ish) Lake Bottom

46 Almost As Dry As It Got

47 French Drain Pit with Well Point Style Pump System

48 Clearing the Berm

49 Continuous Geotechnical Presence

50 Continuous Interface with Client

51 Initial Clearing & Sediment Removal from East Side

52 Cross Vein Installation

53 Completed Cross Vein

54 Bank Stabilization at Cross Vein

55 Continuous Compaction & Testing

56 The Muddy Phase

57 Creekside Bank Stabilization

58 Reuse of Cut Logs for Fish Habitat

59 Stabilized Channel

60 Dressed Walkway & Slopes

61 Hydroseeding Slopes

62 Hydroseed Eating Contest

63 New Natural Channel Developing

64 Existing Original Weir Controls

65 Completed New Inlet Control

66 Completed Walkway

67 Completed Bioretention Feature

68 Phil Howland, City Manager & Director of Public Works Greg Zarus, Mayor, fmr JoAnn Macrina, P.E., Dekalb County Watershed Mgmt, fmr. Jason Bodwell,GEFA Tom Roos, GaDNR