Post Construction Best Management Practices GOING FOR THE GOLD 9/9/2016 THE NEW BMP MANUAL VOLUMETRIC CONTROL PERMITTING AND INSPECETION

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1 Post Construction Best Management Practices GOING FOR THE GOLD PREPARIN G FOR T HE M S4 EN DURAN CE RACE Presentation to SCASM September 8, 2016 THE NEW BMP MANUAL VOLUMETRIC CONTROL PERMITTING AND INSPECETION START THE RACE WITH A PLAN! NEW BMP MANUAL 1

2 UPDATE THE BMP MANUAL Why was the update needed? MS4 permit IDDE Permitting Construction runoff standards Facility Maintenance Enforcement Expand menu of Post Construction BMPs Add needed detail in design standards REFORMATTING FOR CLARITY Previous versions documented the theory that necessitated the regulation Some found the organization cumbersome Just tell me what to do, not why I have to! Sections are laid out to follow the MS4 permit Each section spells out regulations in the progressive steps needed to create a design Fact Sheet format used to group design, construction, and maintenance considerations for BMP in the menu NEW CONTENT The previous BMP manual & Ordinance lacked: Erosion Control / SWPPP plan criteria Illicit Discharge regulations Municipal Facility good housekeeping Enforcement mechanism Permitting process / forms Expanded Post Construction BMPs Irrigation reuse Rain barrels Rain gardens Blue roof 2

3 SUMMARY: DESIGN STANDARDS Reorganized design criteria to outline stormwater system design from the top of the hill to the bottom. Expanded use of various pipe materials based on performance specifications Expanded design storm to multiple events to match other communities (2,, 25, 50, 0 yr) Lowers threshold for permitting and SW Plan to 5,000 sq.ft. Irrigation re-use guidance Clean soil certification for infiltration practices SUMMARY: CHANGES TO POST CONSTRUCTION STANDARDS Effective Imperviousness criteria clarified as a standard, not a goal. Step 2 On-Lot volume control simplified Treatment train of 3 BMPs (det., veg., and infil.) Fact Sheets for each BMP include design, construction, and maintenance considerations Expanded BMP menu Maintenance Agreements will be recorded Know the Facts! Created a Database Developed tools to help homeowners and Engineers 3

4 DATA MANAGEMENT BMP FACT SHEETS The Complexity of Volume Control standards 4

5 Salinity Distributions 40 Summer Salinity (ppt) Sub-urban Forested SH KP DL VR NM YC MC PC SM BL CC LC RT LI HB LH BF 0 DP FT 5 Urban/ Industrial OKATIE RIVER SALINITY IMPACTS Insert DNR slide here. Map too. Salinity May OK OK6 OK5 OK4 OK3 OK2 30 Salinity and rainfall Salinity OK Apr 5-May 3-May 1-May 29-Apr 27-Apr 25-Apr 23-Apr 21-Apr 19-Apr 17-Apr 15-Apr 13-Apr 11-Apr 9-Apr 7-Apr 5-Apr 3-Apr 1-Apr Rainfall (in) Rainfall (mm) OKATIE RIVER SALINITY IMPACTS 20 OK1 0 6-Apr 11-Apr 16-Apr 21-Apr 26-Apr 1-Apr 11-Apr 21-Apr 1-May 5

6 BMP MANUAL PRINCIPLES Peak Controls Water Quality Controls Runoff Volume Controls Stormwater Review Impervious Cover Controls Approved Design EQUIVALENT/EFFECTIVE IMPERVIOUS COVER (EIC) Metric that measures how effectively impervious surface runoff is reduced relative to predevelopment pervious surface runoff 1998 Adopts Antidegradation Goal on % Impervious Surface for Phosphorus Adopts 5% goal for Bacteria 2009 Adopts % goal for Nitrogen 20 Volume control of 95th percentile rainfall event is equivalent to % EIC VOLUME CONTROL REQUIREMENTS Required Volume controls Control runoff for 95 percentile storm event (1.95 inch) Implementation Step 1 New Developments - October 2009 Step 2 On-lot Controls June 20 Individual lot controls to 95 th percentile Can be exempted if development meets Step 1 requirements 6

7 Handling construction runoff Standards for the large and small Developed tools to help homeowners and builders SUMMARY: CONSTRUCTION RUNOFF ALL NEW Construction Runoff Design Criteria Turbidity standard Tier 1 and 2 SWPPP Fact Sheets for EPSC BMPs TIER I SWPPP TEMPLATE 7

8 FACT SHEET EXAMPLE CREATE AN INSPECTION POST CONSTRUCTION INSPECTION TO FOLLOW! Illicit Discharge Program Municipal Spill Prevention / Good Housekeeping 8

9 SUMMARY: IDDE ALL NEW Illicit Discharge and Detection program defined Monitoring Plan defined Heavy referencing of a revised Stormwater Ordinance Reporting app., hotline BEAUFORT CO. CONNECT Mobile app that: Allows citizen report a variety of complaints, including stormwater Geotags photos Website to check status Internal complaint tracking ability IDDE SCREENING 9

10 SUMMARY: MCM6 ALL NEW Municipal Facility Good House keeping and spill prevention program defined For buildings and the MS4 Fact sheets for BMPs The Environmental Handbook EXAMPLE FACT SHEET CONGRATS! HOW TO STAY IN GOOD CONDITION! Annual Inspections Enforcement

11 SUMMARY: COMPLIANCE ALL NEW Inspection and Enforcement References Ordinance and summarizes penalties and fines Revised Ordinance - Chapter 99 Article I reserved (unused) Article II SW Utility. Defines rate structure, fees, Board New Article III. Regulatory Provisions New Article IV. Design Standards New Article V. Illicit Discharge New Article VI. Inspection, Enforcement ANNUAL TRACKING VIOLATION REPORTS 11

12 PREPARE FOR THE NEXT RACE! Education is ongoing (Carolina Clear/Lowcountry Stormwater Partners) Start with staff Planning, Inspectors, and operations Reaching out to the development community QUESTIONS? Eric W Larson, PE, CPSWQ, AICP, CFM Stormwater Manager elarson@bcgov.net Rebecca Baker MS4 Coordinator rbaker@bcgov.net SC Association of Stormwater Managers 3rd Quarter Meeting Thursday, September 8 Columbia Conference Center 12