June 12, 2018 Summit Soil and Water Conservation District 1 Agenda - PowerPoint PPT Presentation

June 12, 2018 Summit Soil and Water Conservation District 1

Agenda • Review • Construction General Permit Updates and History • Transitioning from Old to New • Breaks/snacks • Calculating Ohio's WQv and Rv • Questions • Certificate for 3 PDH’s (0.3 CEUs) for attendance Summit Soil and Water Conservation District 2

Th The O e OEP EPA NP A NPDE DES Con S Constr truction uction Ge Gene neral al Pe Permi mit ren enew ewed ed 4-23 23-201 2018 Summit Soil and Water Conservation District 3

SWP3 SWP3 Design Approval Summit Soil and Water Conservation District

St Stor orm m Wa Water er Po Pollution ution Pr Prev event ention ion Pl Plan an • Submittals: timeline/fees/requirements • Review: timelines/plan requirements • Approval Summit Soil and Water Conservation District 5

Start at the Beginning… • An SWP3 is required if your site will result in soil disturbing activity of 1 acre or more (or less than one acre if part of a larger common plan of development or sale). • The SWP3 must be submitted for review and approval prior to starting the site. Summit Soil and Water Conservation District 6

De Definitions: finitions: • Disturbed : Clearing, grubbing, grading, excavating, filling, or other alteration of the earth’s surface where natural or human made ground cover is destroyed. • Acre: a measurement of area equaling 43,560 square feet Summit Soil and Water Conservation District 7

Subm ubmitting itting a P a Plan an • 2 page application. • Review fee • One full set of the construction plans (24x36). • All supporting calculations. • One 11x 17” set (or PDF) • Copy of the Long Term Operation & Maintenance Plan • OEPA Notice of Intent permit number Summit Soil and Water Conservation District 8

Re Review view & Ins Inspection pection Fe Fees es • SWP3 is $40.00 per acre for the total site acreage. • Timbering SWP3 (if separate) is $40.00 per acre for area being timbered. • Grading SWP3 (if separate) is $40.00 per acre for total site acreage. • Inspection fee is based on area disturbed. Summit Soil and Water Conservation District 9

Ot Othe her r Fe Fees es Individual lot SWP3 • $75.00 if within a subdivision • $150.00 if site is not in a subdivision • Sites with a Notice of Violation will incur a $250.00 reinspection fee Summit Soil and Water Conservation District 10

Re Review view • The District has 30 days to review the SWP3 and comment. • The approved SWP3 is valid for 2 years. • A review letter will be sent detailing deficiencies. • Sometimes a call or meeting is needed. ALL plans are important. Summit Soil and Water Conservation District 11

Wh Who o re reviews views my pl plan? an? Julie Berbari Stephanie Deibel Alina Godbey Summit Soil and Water Conservation District 12

SWP3 WP3 Plan an Gu Guidance dance • Visit our web page at www.summitswcd.org • SWP3 Checklist (Including all required items moves the review process along) • Regulations-on line to review • Rain Water & Land Development Manual-on line for guidance. • Water Quality Volume Calculator and BMP Design Worksheet Summit Soil and Water Conservation District 13

Changes to Ohio’s Construction General Permit Jason Fyffe/John Mathews Ohio EPA, Division of Surface Water Storm Water

Construction General Permit (C (CGP) Basic ESC during construction, general Increased sediment storage; narrative re: post- required skimmers on Sed. construction stormwater; basins; offsite mitigation of Major review of post- (≥5 acres of disturbance) post-const. allowed construction requirements 1992 2003 2008 2013 2018 ≥ 1 acre; Added p ost- Minor changes construction (≥ 5; 1 -5 ac)

The Process • Early Stakeholder Outreach – May to Dec. 2017 • Draft Permit – February, 2018 • More meetings with stakeholders • Comments submitted April 4, 2018 • OHC00005 Permit Issued on April 23

2017-2018 Review of f Post-Construction Two issues Ohio EPA hoped to address in renewal: 1. Reduce ineffective (or failure to apply) post-construction BMPs on small sites 2. Water quality volume equation – was it meeting the 80% TSS goal? • Update w/ latest data evaluate for average annual runoff • Assess the volumetric runoff coefficient (C). WQv = P wq × C × A disturbed ÷ 12

Draft ft Permit-Proposed Changes 1. Submittal of all plans (SWP3) 2. Remove 2 bullets re sediment basins: 12” sediment barriers in place of silt fence 3. Post-Construction SW A. WQv capture (Table 2) practice for all developments > 1 ac B. WQv Calculation: i. Volumetric runoff coefficient equation to Rv = 0.05 + 0.9i ii. Increase precipitation (P) from 0.75 to 0.9 inches C. Add to Table of Practices D. Credit green infrastructure practices (reduce the WQv) E. Redevelopment – 20% of WQv w/ green infrastructure practice; or 40% of WQv w/ standard practice F. Alternative practices: testing, particle size distribution and WQF 4. On-site infiltration for Big Darby groundwater recharge 5. Next inspection after rainfall: on the next work day 6. Combine all CGP permits

New Permit 1. Submittal of all plans (SWP3): Big Darby/Olentangy 2. Remove 2 bullets re sediment basins: 12” sediment barriers in place of silt fence 3. Post-Construction SW A. WQv capture (Table 4a/4b) practice for all developments:1-1.99 B. WQv Calculation: i. Volumetric runoff coefficient equation to Rv = 0.05 + 0.9i ii. Increase precipitation (P) from 0.75 to 0.9 inches C. Add to Table of Practices D. Credit green infrastructure practices (reduce the WQv) E. Redevelopment – 20% of WQv w/ green infrastructure practice; or 40% of WQv w/ standard practice F. Alternative practices: testing, particle size distribution and WQF 4. On-site infiltration for Big Darby groundwater recharge 5. Next inspection after rainfall: on the next work day 6. Combine all CGP permits (Olentangy CGP in effect till 5/2019)

Changes to the Permit Online submittal of SWP3 is requested , but not required (except in Big Darby Creek and portions of the Olentangy River watersheds)

Changes to the Permit Sediment basins and sediment barriers clarifications • All sed. basins have drain times of 48 hours • Sediment basins are appropriate for sites < 10 ac • Minimum size sediment barrier as replacement for silt fence “For most applications, standard silt fence is replaced with 12" diameter filter socks.” (Rainwater and Land Development manual, updated 11-6-14 . Chapter 6, page 48.

Post-Construction Changes WQv = Rv · P · A / 12 Where, WQv = water quality volume Rv = 0.05 + 0.9i (from 0.858i^3 - 0.78i^2 + 0.774i + 0.04) P = precipitation of 0.9 (from 0.75) A = disturbed area OR contributing drainage area

Post-Construction Changes Capture WQv in a Table 4a/4b practice for all developments For < 2 acres • May use an alternative practice if you show that 4a/4b are not feasible and the regulated MS4 approves • Green infrastructure BMPs are encouraged

Post-Construction Changes Additional options and notes for the table of acceptable practices (formerly table 2)

Underground Storage – Extended Detention 1. Outlet structure shall not discharge more than the first half of the WQv in less than one-third of the drain time. 4. Must have pretreatment for removal of suspended sediments. This pretreatment shall concentrate sediment in location where it can be readily removed. For non-infiltrating systems, pretreatment shall be 50% effective at capturing total suspended solids according to the testing protocol established in the Alternative Post Construction BMP testing protocol.

Underground Storage – Infiltration 3. Subsurface practices designed to fully infiltrate the WQv shall empty within 48 hours to recover storage for subsequent storm events. 4. Must have adequate pretreatment of suspended sediments. Pretreatment shall concentrate sediment in a location where it can be readily removed. Examples include media filters situated upstream of the storage or others approved by OEPA. For infiltrating systems, pretreatment shall be 80% effective at capturing total suspended solids according to the testing protocol established in the Alternative Post Construction BMP testing protocol.

Runoff Reduction Practices The WQv can be reduced by incorporating runoff reducing practices into the design of the site’s drainage system. 1. Bioretention 2. Infiltration basin/trench 3. Permeable pavement with infiltration 4. Underground storage with infiltration 5. Grass swale 6. Sheet flow to filter strip 7. Sheet flow to conservation area 8. Impervious surface disconnection 9. Rainwater harvesting 10.Green Roof

Alt lternative Practices Alternative practices must be tested to show equivalency to the table of acceptable practices • (80% TSS and extended detention if not a negligible discharge impact of the discharge). • Specifies minimum particle size distribution similar to NJ DEP • NJ DEP reviewed testing or Washington State TAPE testing accepted • Water quality flow practices must use table of intensities for Tc less than 60 minutes.