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Proposed Virginia Stormwater Management Regulations

2. Agenda. State Stormwater Regulation ChangesSchedule and Process for Final ChangesProject ExamplesLocality Impacts. 3. Significant Stormwater Regulation Changes. Part I: DefinitionsPart II: More Restrictive Technical CriteriaWater QualityBMPsWater QuantityDetentionPart III: Locality Del

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Proposed Virginia Stormwater Management Regulations

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    1. 6/15/2012 Proposed Virginia Stormwater Management Regulations

    2. 2 Agenda State Stormwater Regulation Changes Schedule and Process for Final Changes Project Examples Locality Impacts

    3. 3 Significant Stormwater Regulation Changes Part I: Definitions Part II: More Restrictive Technical Criteria Water Quality BMPs Water Quantity Detention Part III: Locality Delegation Submission, Review and Approval of Plans Long Term BMP Inspection & Reporting to DCR Part XIII: Increased Permit Fees Individual/general permits Fees Transfer of Permits Fees Annual Permit Maintenance Fees BMP Clearinghouse and Blue Book Offsets

    4. 4 Stormwater Management Regulations Technical Criteria (Part II) Current Regulations: Total phosphorous removal Removal rate typically 0.45 lbs/acre/year 10% reduction for redevelopment Nutrient loads based on impervious cover Draft Regulations: TP still required, also need to calculate Total Nitrogen Removal rate = 0.28 lbs/acre/year 20% reduction for redevelopment Nutrient loads based on impervious cover and managed turf

    5. 5 Stormwater Management Regulations Technical Criteria (Part II) Water Quality Changes Localities may apply criteria to each drainage area rather than project site If land disturbance occurs on a portion of a site, locality may apply criteria to that portion rather than project site Criteria must be applied independently within each HUC Off-site controls may be used if allowed by locality Development must use the Runoff Reduction Method to achieve water quality results

    6. 6 Stormwater Management Regulations Technical Criteria (Part II) BMP Changes BMPs will be approved through BMP Clearinghouse and Blue Book BMP efficiencies will be set in Runoff Reduction Spreadsheet Removal based on 1 inch of rainfall over treated area BMP Designs have 2 levels Level 1: standard design Level 2: enhanced design to increase efficiency

    7. 7 Stormwater Management Regulations Technical Criteria (Part II) Approved BMPs: Green Roof Rooftop Disconnection Rain Tanks/Cisterns Soil Amendments Permeable Pavement Grass Channel Bioretention Infiltration Dry Swale Wet Swale (Coastal Plain) Sheet Flow to Open Space Extended Detention Filtering Practice Constructed Wetland Wet Pond

    8. Stormwater Nonpoint Nutrient Offsets HB 2168 Effective July 2009 Applied to Chesapeake Bay watershed tributaries Can be used to meet water quality requirements only Must be consistent with local MS4 plan and TMDLs 8 Stormwater Management Regulations Technical Criteria (Part II)

    9. 9 Stormwater Management Regulations Technical Criteria (Part II) Water Quantity Changes Channel Protection: Manmade conveyance system: no erosion from 2-year 24-hour storm Restored natural conveyance system: can not exceed design capacity of the channel or result in instability Stable natural conveyance system: Qdeveloped*RVdeveloped<Qpre-developed*RVpre-developed Unstable natural conveyance system: Qdeveloped*RVdeveloped<Qforested*RVforested Qdeveloped=allowable peak flow from developed site Qpre-developed=peak flow from pre-developed site Qforested=peak flow from site in forested condition RVdeveloped=volume of runoff from developed site RVpre-developed=volume of runoff from pre-developed site RVforested=volume of runoff from site in forested condition

    10. Stormwater Management Regulations Technical Criteria (Part II) Water Quantity Changes Flood Protection: Manmade conveyance system: confine 10-year 24-hour storm Restored natural conveyance system: confine 10-year 24-hour storm Natural conveyance system that does not flood: confine 10-year 24-hour storm Natural conveyance system that does flood: peak flow rate from post-developed 10-year 24-hour storm not to exceed peak flow rate from pre-developed 10-year 24-hour storm based on forested conditions 10

    11. Stormwater Management Regulations Technical Criteria (Part II) Water Quantity Changes One Percent Rule: Channel Protection and Flood Protection do not apply if Sites drainage area is < 1.0% of total contributing drainage area Or Peak flow rate from one-year 24-hour storm for post-development site conditions (prior to quantity control) is less than 1.0% of the existing one-year 24-hour storm for the total watershed area 11

    12. Stormwater Management Regulations Technical Criteria (Part II) Water Quantity Changes All pre-development runoff from prior developed sites shall be assumed in good hydrologic condition TR-55 and TR-20 used for analysis Localities may allow Rational or Modified Rational Stormwater harvesting is encouraged 12

    13. Stormwater Management Regulations Permit Application Fees (Part XIII) CBPA: 2,500 Sq.Ft. 0.5 acre $290 CBPA: 0.5 acre 1 acre $1,500 1.0 acre 5.0 acres $2,700 5.0 acres 10 acres $3,400 10 acres 50 acres $4,500 50 acres 100 acres $6,100 100 acres + $9,600 Individual Permit $15,000 13

    14. Stormwater Management Regulations Permit Modification or Transfer Fees CBPA: 2,500 Sq.Ft. 0.5 acre $20 CBPA: 0.5 acre 1 acre $100 1.0 acre 5.0 acres $200 5.0 acres 10 acres $250 10 acres 50 acres $300 50 acres 100 acres $450 100 acres + $700 Individual Permit $5,000 14

    15. Stormwater Management Regulations Annual Permit Maintenance Fees CBPA: 2,500 Sq.Ft. 0.5 acre $50 CBPA: 0.5 acre 1 acre $200 1.0 acre 5.0 acres $400 5.0 acres 10 acres $500 10 acres 50 acres $650 50 acres 100 acres $900 100 acres + $1,400 Individual Permit $3,000 15

    16. 16 Stormwater Regulations Schedule June 22 August 21 2009 60-day public comment August - September 2009 DCR revisions after public comment October 2009 Virginia Soil and Water Conservation Board approval December 2009 Final regulation published July 2010 Final regulation effective October 2011 Localities implement stormwater - April 2012 programs

    17. 17 Agenda State Stormwater Regulation Changes Schedule and Process for Final Changes Project Examples Locality Impacts

    18. Example 1: Site Layout with Current Regulations

    19. Example 1: Site Layout with Proposed Regulations

    20. Example 1: Summary Current Regulations Required Removal 167.0 lbs/yr Method of Removal 3.30 ac. Wet Pond #1 Number of BMPs 2 Stormwater Cost $1,000,000 $5,988/lb Total Cost = $1,000,000 Proposed Regulations Required Removal 200.5 lbs/yr Method of Removal 1.95 ac. Bioretention #1 1.50 ac. Bioretention #2 4.55 ac. Wet Pond #2 1.0 ac. Pervious Pavement Number of BMPs 28 Stormwater Cost $3,801,980 $18,962/lb Lost Acreage 1.62 Ac. @ $500,000/ac. $810,000 Total Cost = $4,611,980

    21. Example 2: Site Layout with Current Regulations

    22. Example 2: Site Layout with Proposed Regulations

    23. Example 2: Summary Current Regulations Required Removal 36.54 lbs/yr Method of Removal Underground StormFilter System Number of BMPs 2 Stormwater Cost $650,000 $17,789/lb Total Cost = $650,000 Proposed Regulations Required Removal 45.58 lbs/yr Method of Removal 0.46 ac. Pervious Pavement 0.36 ac. Bioretention #1 1.60 ac. Wet Pond #2 Number of BMPs 14+ Stormwater Cost $780,319 $17,120/lb Lost Acreage 1.64 ac. @ $500,000/ac. $820,000 Total Cost = $1,600,319

    24. Example 3: Site Layout with Current Regulations

    25. Example 3: Site Layout with Proposed Regulations

    26. Example 3: Summary Current Regulations Required Removal 57.18 lbs/yr Method of Removal Paid into Local Program Fund Number of BMPs Zero Stormwater Cost $349,084 $6,105/lb Total Cost = $349,084 Proposed Regulations Required Removal 67.26 lbs/yr Method of Removal 1.51 ac. Bioretention #1 2.16 ac. Wet Pond #2 Number of BMPs 29 Stormwater Cost $1,276,880 $18,984/lb Lost Acreage 1.51 ac. @ $500,000/ac. $755,000 Total Cost = $2,031,880

    27. Example 4: Site Layout with Current Regulations

    28. Example 4: Site Layout with Proposed Regulations

    29. Example 4: Summary Current Regulations Required Removal 0.20 lbs/yr Method of Removal Permeable Pavement Number of BMPs 1 Stormwater Cost $80,150 $400,752/lb Total Cost = $80,150 Proposed Regulations Required Removal 0.40 lbs/yr Method of Removal Permeable Pavement Green Roof Number of BMPs 2 Stormwater Cost $280,526 $701,315/lb Total Cost = $280,526

    30. Example 5: Site Layout with Current Regulations

    31. Example 5: Site Layout with Proposed Regulations

    32. Example 5: Summary Current Regulations Required Removal 4.88 lbs/yr Method of Removal Bioretention Filterras Extended Detention Number of BMPs 7 Stormwater Cost $157,183 $32,209/lb Total Cost = $157,183 Proposed Regulations Required Removal 22.94 lbs/yr Method of Removal Permeable Pavement Bioretention Dry Swale Number of BMPs 20 Stormwater Cost $1,674,882 $73,011/lb Total Cost = $1,674,882

    33. Reference Information Latest Version of Parts I, II, and III Draft Regulations: http://www.dcr.virginia.gov/lr2c.shtml Latest Version of Parts I, II, and III Draft Regulations: http://www.dcr.virginia.gov/lr2b.shtml Economic Impact Analysis: http://www.dcr.virginia.gov/lr2b.shtml Runoff Reduction Method: http://www.dcr.virginia.gov/lr2f.shtml BMP Clearinghouse: http://www.vwrrc.vt.edu/swc/ 33

    34. 34 Agenda State Stormwater Regulation Changes Schedule and Process for Final Changes Project Examples Locality Impacts

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