1 / 35

Achieving Flood Mitigation Through Stormwater Management: Ideas, Examples, and Advice

Achieving Flood Mitigation Through Stormwater Management: Ideas, Examples, and Advice. “Breaking the Cycle” New Jersey Association of Floodplain Management 8 th Annual Conference October 2 - 3, 2012. Cost-Effective Flood Protection. New Jersey Association for Floodplain Management

micol
Download Presentation

Achieving Flood Mitigation Through Stormwater Management: Ideas, Examples, and Advice

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Achieving Flood Mitigation Through Stormwater Management:Ideas, Examples, and Advice “Breaking the Cycle” New Jersey Association of Floodplain Management 8th Annual Conference October 2 - 3, 2012

  2. Cost-Effective Flood Protection New Jersey Association for Floodplain Management 5th Annual Conference October 15 - 16, 2009

  3. What’s in a Name? NJAFM 2012 Annual Conference - "Breaking the Cycle" Flood Control Flood Protection Flood Reduction Flood Mitigation Flood Management

  4. Flood Mitigation vs. Stormwater Management • Flood Mitigation: • Reduces Existing Flood Damage to Existing Development • Performed by the Existing Development • Stormwater Management: • Prevents New or Additional Flood Damage Caused by New Development • Performed by the New Development NJAFM 2012 Annual Conference - "Breaking the Cycle"

  5. Flood Mitigation vs. Stormwater Management Both Achieve Flood Damage Reduction Both Achieved through Structural and Nonstructural Measures Using Stormwater Management to Achieve Flood Mitigation can Help Overcome Our Largest Flood Mitigation Obstacle: NJAFM 2012 Annual Conference - "Breaking the Cycle"

  6. $ NJAFM 2012 Annual Conference - "Breaking the Cycle"

  7. However…. NJAFM 2012 Annual Conference - "Breaking the Cycle"

  8. Flood Mitigation vs. Stormwater Management • Flood Mitigation: • Reduces Existing Flood Damage to Existing Development • Performed by the Existing Development • Stormwater Management: • Prevents New or Additional Flood Damage Caused by New Development • Performed by the New Development NJAFM 2012 Annual Conference - "Breaking the Cycle"

  9. NJAFM 2012 Annual Conference - "Breaking the Cycle"

  10. NJAFM 2012 Annual Conference - "Breaking the Cycle"

  11. Rational Nexus “ Many state courts have resolved these conflicts by adopting some variation of the ‘rational nexus’ rule, under which a municipality can compel a developer to shoulder only those costs that bear a rational nexus to needs created by … the development.” NJAFM 2012 Annual Conference - "Breaking the Cycle"

  12. Rational Nexus Example: Peak Rate Reduction Factors in NJDEP Stormwater Management Rules, RSIS, and Municipal Stormwater Control Ordinances DO NOT Reduce Existing Flows or Flooding. Instead, They Prevent Existing Flows from Increasing. NJAFM 2012 Annual Conference - "Breaking the Cycle"

  13. Peak 100-Year Flow Comparison From: 1986 South Branch Rockaway Creek Stormwater Management Study by NJDEP and NRCS NJAFM 2012 Annual Conference - "Breaking the Cycle"

  14. Developed = 80% of Existing100-Year Peak From: 1993 Middle Brook Watershed Stormwater Management Plan by HMM and Somerset County NJAFM 2012 Annual Conference - "Breaking the Cycle"

  15. ? NJAFM 2012 Annual Conference - "Breaking the Cycle"

  16. Conservation of Mass Stormwater Management Flood Mitigation $ NJAFM 2012 Annual Conference - "Breaking the Cycle"

  17. Conservation of Mass Stormwater Management Flood Mitigation $ $ NJAFM 2012 Annual Conference - "Breaking the Cycle"

  18. Conservation of Mass Stormwater Management Flood Mitigation $ $ $ NJAFM 2012 Annual Conference - "Breaking the Cycle"

  19. Proposed Major Development Downstream Runoff Quantity Impacts? YES NO Full Onsite Quantity Control and Cost No or Reduced Onsite Quantity Control and Cost Cost Savings to Flood Mitigation Fund NJAFM 2012 Annual Conference - "Breaking the Cycle"

  20. Flood Mitigation Fund Increase Quantity Control at Major Development Flood Mitigation Project NJAFM 2012 Annual Conference - "Breaking the Cycle"

  21. West Branch Reservoir Dam West Branch Middle Brook Reservoir • In Hanken Road Neighborhood: • Flood Threshold Increased from 5-Year (20%) to 25-Year (4%) • 100-Year Flooding Reduced to 25-Year Levels • No Flooding from Middle Brook During Tropical Storm Floyd Middle Brook Raritan River NJAFM 2012 Annual Conference - "Breaking the Cycle"

  22. Middle Brook Watershed Study • Completed in 1994 • Developed for Somerset County • Funded by NJDEP Phase II Stormwater Grant • Total Drainage Area = 17 Square Miles NJAFM 2012 Annual Conference - "Breaking the Cycle"

  23. Princeton Regional Basin G NJAFM 2012 Annual Conference - "Breaking the Cycle"

  24. Princeton Regional Basin G NJAFM 2012 Annual Conference - "Breaking the Cycle"

  25. What’s Needed? Data and Ability to Reliably Determine “No Downstream Runoff Quantity Impacts” Watershed-Based Plans and Computer Models Extremely Helpful Open and Objective Decision Criteria Open and Accurate Contribution Accounting System NJAFM 2012 Annual Conference - "Breaking the Cycle"

  26. Any Other Problems? New Jersey Stormwater Management Rules (NJAC 7:8)? Municipal Stormwater Control Ordinances? Municipal NJPDES General Stormwater Discharge Permits? All Cite Regional Stormwater Management and Mitigation Planning NJAFM 2012 Annual Conference - "Breaking the Cycle"

  27. Summary Stormwater Management Measures Prevent New, Not Reduce Existing Flooding (“Don’t Make it Worse”) Need to Revive “We Can Make It Better” Approach of In-Lieu Contributions to Flood Mitigation Fund Need to Identify Possible Regulatory Constraints and Remove Them NJAFM 2012 Annual Conference - "Breaking the Cycle"

  28. All Funded by NJDEP Phase II Regional Stormwater Management Planning Grants NJAFM 2012 Annual Conference - "Breaking the Cycle"

  29. Two Final Thoughts If There’s Time NJAFM 2012 Annual Conference - "Breaking the Cycle"

  30. #1 - Understand Your Problem • Understand the Hydrology and Hydraulics of Your Flood Problems and Their Watersheds Before Considering Solutions • Frequency • Discharge Rate and Volume • Capacities • Location and Topography • Water Surface Elevations • Damages NJAFM 2012 Annual Conference - "Breaking the Cycle"

  31. #1 - Understand Your Problem • Understand and Rank What Influences Flood Problems: • Discharge Rate and/or Volume • Site and Downstream Hydraulic Capacity • Damageable Structures and Infrastructure • Understand What Doesn’t Influence Problem • Be Objective - Do Not Look for “Blame” • Understand and Embrace Natural Reality of Floodplains NJAFM 2012 Annual Conference - "Breaking the Cycle"

  32. #1 - Understand Your Problem Find the Solution that Fits Your Problem Do NOT Force the Problem to Fit Your Solution NJAFM 2012 Annual Conference - "Breaking the Cycle"

  33. #2 – Finding Funding Population of New Jersey = 8,791,894 (2010 Census) Assume One Half Pay State Income Tax = 4,395,947 Assume Each Pays $1 per Month “Flood Mitigation Fee” 4,395,947 X $1 X 12 Months = $52,751,364 Available Annually for Flood Mitigation NJAFM 2012 Annual Conference - "Breaking the Cycle"

  34. #2 – Finding Funding Not a Tax but a Fee Paid to Continue to Discharge Stormwater Runoff and It’s Consequences Based Upon the Fact that Everyone in New Jersey is Part of the Problem Slogan: “It May Not Be Your House, But It is Your Floodwater” NJAFM 2012 Annual Conference - "Breaking the Cycle"

  35. Joseph J. Skupien, PE, PPPresidentStorm Water Management Consulting, LLC1108 Old York RoadP.O. Box 727Ringoes, New Jersey 08551Phone: 908-806-7700Fax: 908-806-7721joeskupien@swmconsulting.com NJAFM 2012 Annual Conference - "Breaking the Cycle"

More Related