Gwinnett County Dept. of Water Resources Watershed Improvement Program. Russell Manley, CFM, Gwinnett County DWR Kevin Middlebrooks, CH2M

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1 Gwinnett County Dept. of Water Resources Watershed Improvement Program Russell Manley, CFM, Gwinnett County DWR Kevin Middlebrooks, CH2M

2 Gwinnett County: Population: 859,000 Area: 437 sq. miles 2,000 miles drainage system 91,000 structures maintained

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4 40+ Projects Completed 1,312 Stream Miles Assessed (66%) Approximately 31,500 FT Stream Rehabilitated (6 Miles) 2.5 Million FT 3 Pond Volume Created or Enhanced (57.4 Acre Feet) 5.5 Million LB/YR TSS Removed

5 Improve/Protect Water Quality (TSS Reduction) Improve Aquatic Integrity/Habitat Meet Permit Requirements Meet WQ Standards/Designated Use Provide Amenity to Community.Improve Natural & Urban Environment

6 Construction Altered Hydrology Impervious Surfaces Dredging Buffer Encroachment

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8 Water Quality Channel Instability Flooding

9 Achieve Channel Stability By Establishing A Stable Dimension, Pattern and Profile Such That, Over Time, The Channel Neither Aggrades or Degrades Re-Establish Form and Pattern-Reference Reach Bankfull Dimensions-Width, Depth Meander-Sinuosity, Length, Width Riffle, Pool Placement Floodplain Connectivity Reduce Energy & Stress On Banks & Channel Re-Grading Stream Banks & Channels Grade Control (Channel) Flow Deflection-Rock & Log Vanes / J-hooks Bank Protection / Armoring-Vegetation, Stone, Geotechnical Materials

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12 Project identified in the Chattahoochee Tributaries Watershed Improvement Plan Located in Peachtree Station Subdivision Project Boundary Consists of 26 Residential Properties Includes Three Stream Reaches

13 Lower Sapelo Tributary 116 Acre Drainage Area 1020 Feet Restoration Upper Sapelo Tributary 62 Acre Drainage Area 1,082 Feet Design Restoration Flippen Tributary 36 Acre Drainage Area 593 Feet Design Restoration Lower Sapelo Tributary 116 Acre Drainage Area 1020 Feet Design Restoration 29% Impervious Cover Flippen Tributary 36 Acre Drainage Area 593 Feet Restoration Upper Sapelo Tributary 62 Acre Drainage Area 1,082 Feet Restoration

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15 Location of Historic Dam

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17 Design Summary: 2,695 Feet Design Restoration (~0.5 Miles) 7.7 Acres Project Area 3.3 Acres Riparian Buffer Enhancement ~5,000 YD 3 Earth Cut/Fill. Balanced On-Site ~10 Month Construction Schedule 290,000 Lbs/Yr TSS Reduction 61 Grade Control Structures Installed Permits with USACE, GAEPD, and Gwinnett Planning & Development (LIA)

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20 Multiple Public Meetings Property Owner Expectations vs Sound Design Permitting and Design Restrictions Easement Acquisition Lessons Learned

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22 Explain Objectives and Benefits of WIP Identify Access Review Conceptual Ideas Q&A Build Support for Project

23 Two Agreements Required For Project Implementation: Drainage Easement (Permanent) Drainage Easement On Project Corridor Provides County Access To The Site For Monitoring and Maintenance Prevents Certain Activities Within Project Corridor (Grading, Filling, Clearing, etc.) Right of Entry (Temporary) Provides Access To Homeowner Property For The Purposes Of Construction Activity

24 Multitude of Different Ideas Landscaping & Maintenance Insects and Pests Control Aesthetics Property Values

25 Not Everyone Can Have the Step-Pools Based Upon Valley Type and Slope Different Stream Types Throughout the 3 Reaches Due to Natural Variations and Relict Dam Work Around Property Owner Not Cooperating Must Design, Build & Vegetate Based Upon Parameters Set By Federal, State & Local Permits and Regulations Homeowner Assets Restore Access

26 Communicate Objectives Early In The Project Listen To Homeowner Feedback Great Knowledge Of The Stream and How It Responds To Storm Flows Expect Different Opinions, but Educate On Function, Regulatory Requirements, and Long-Term Stability Manage Expectations For Mess During Construction Landscaping vs Natural Riparian Buffer Equal Level Of Service Between Property Owners Maintain Regular Communication and Updates While Projects Are Self-Sustaining, Some Level of Monitoring and Maintenance Is Expected Following Construction Every Communication With Homeowner Is An Opportunity To Educate and Build Support For Watershed Conservation

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