A BMP Siting and Prioritization Plan to Address the Jordan Rules for Existing Development

Transcription

1 A BMP Siting and Prioritization Plan to Address the SESWA 2012 Annual Conference Chattanooga, TN October 2012 Jacquelyn Corbin, CDM Smith

2 Outline Introduction: Water Quality Impairments Resolving Water Quality Impairments Nutrient Management Strategies Neuse Tar Pamlico Falls Lake Jordan Lake A BMP Siting and Prioritization Plan Greensboro, NC Conclusions

3 Introduction: Brief History of Water Quality Impairments Nationwide Concerns: Eutrophication Fish kills Increased cost to treat drinking water supply NC

4 Jordan Rules for Existing Development

5 Impaired Waters by State: Alabama Florida Georgia Kentucky Mississippi North Carolina South Carolina Tennessee

6 Outline Introduction: Water Quality Impairments Resolving Water Quality Impairments Nutrient Management Strategies Neuse Tar Pamlico Falls Lake Jordan Lake A BMP Siting and Prioritization Plan Greensboro, NC Conclusions

7 Resolving Water Quality Impairments TMDL or restoration plans Active development and implementation of programs all over the U.S. Watershed Implementation Plans (WIPs) Numeric Nutrient Criteria Nutrient Management Strategies

8 Outline Introduction: Water Quality Impairments Resolving Water Quality Impairments Nutrient Management Strategies Neuse Tar Pamlico Falls Lake Jordan Lake A BMP Siting and Prioritization Plan Greensboro, NC Conclusions

9 Nutrient Management Strategies

10 Nutrient Management Strategies Strategy DA (sq mi) Effective Buffer Rules Fertilizer Mngt. Non Point Source Development Existing New Agriculture Waste Water Tar Pamlico River 5, X X X MEP X X Neuse River 6, X X X MEP X X Jordan Lake 1, X X X X X X Falls Lake X X X X X X

11 Tar Pamlico River Nutrient Strategy

12 Tar Pamlico Nutrient Strategy Overall Nutrient Reduction Goal (1991 baseline) Total Nitrogen = 30% Reduction Total Phosphorus = 0% Reduction (i.e. no chg) Existing Development MEP New Development Total Nitrogen = 4.0 lbs/ac/yr Total Phosphorus = 0.4 lbs/ac/yr

13 The Neuse Rules

14 Neuse Nutrient Strategy Rules Overall Nutrient Reduction Goal ( baseline) Total Nitrogen = 30% Reduction Total Phosphorus = n/a Existing Development MEP New Development Total Nitrogen = 3.6 lbs/ac/yr Total Phosphorus = n/a

15 Jordan Lake Nutrient Management Strategy

16 Jordan Lake Nutrient Strategy Rules Overall Nutrient Reduction Goal ( baseline) Total Nitrogen: Upper New Hope = 35% Lower New Hope = 0% Haw River = 8% Total Phosphorus: Upper New Hope = 5% Lower New Hope = 0% Haw River = 5%

17 Jordan Lake Nutrient Strategy Rules Existing Development Stage 1: Adaptive Management Program Stage 2: Upper New Hope (2014) Total Nitrogen = 8% Reduction Total Phosphorus = 5% Reduction Lower New Hope and Haw River (2017) Total Nitrogen = 8% Reduction Total Phosphorus = 5% Reduction Additional Measures (2023): Upper New Hope to reduce Total Nitrogen by 35%

18 Jordan Lake Nutrient Strategy Rules New Development (2014, was 2012) Upper New Hope: Total Nitrogen = 2.2 lbs/ac/yr Total Phosphorus = 0.82 lbs/ac/yr Lower New Hope: Total Nitrogen = 4.4 lbs/ac/yr Total Phosphorus = 0.78 lbs/ac/yr Haw River: Total Nitrogen = 3.8 lbs/ac/yr Total Phosphorus = 1.43 lbs/ac/yr

19 Falls Lake Nutrient Management Strategy

20 Falls Lake Nutrient Strategy Rules Overall Nutrient Reduction Goal (2006 baseline) Stage 1 (achieved by 2021) Lower Falls Achieve water quality standard Upper Falls Improve water quality Stage 2 (achieved by 2041) Upper and Lower Falls Achieve water quality standard

21 Falls Lake Nutrient Strategy Rules Existing Development Stage 1 (by 2021): Post Baseline to New Development Rule Total Nitrogen = 2.89 lbs/ac/yr (~20% Reduction) Total Phosphorus = 0.63 lbs/ac/yr (~40% Reduction) Stage 2 (by 2041): Total Nitrogen = 40% Reduction Total Phosphorus = 77% Reduction New Development Total Nitrogen = 2.2 lbs/ac/yr Total Phosphorus = 0.33 lbs/ac/yr

22 Nutrient Management Strategies Existing Development Summary Strategy DA (sq mi) Effective Total Nitrogen (%Reduction) Total Phosphorus (%Reduction) Tar Pamlico River 5, MEP No Change Neuse River 6, MEP n/a Jordan Lake 1, UNH = 35% LNH = 8% Haw = 8% UNH = 5% LNH = 5% Haw = 5% Falls Lake % 77%

23 Nutrient Management Strategies New Development Summary Strategy DA (sq mi) Effective Total Nitrogen (lbs/ac/yr) Total Phosphorus (lbs/ac/yr) Tar Pamlico River 5, Neuse River 6, n/a Jordan Lake 1, UNH = 2.2 LNH = 4.4 Haw = 3.8 UNH = 0.82 LNH = 0.78 Haw = 1.43 Falls Lake

24 Outline Introduction: Water Quality Impairments Resolving Water Quality Impairments Nutrient Management Strategies Neuse Tar Pamlico Falls Lake Jordan Lake A BMP Siting and Prioritization Plan Greensboro, NC Conclusions

25 North Buffalo Creek A BMP Siting Case Study North Buffalo Creek Raleigh Jordan Lake

26 How Do You Achieve 8% Total Nitrogen and 5% Total Phosphorus Reduction? Retrofit existing developed areas with BMPs Wet Ponds Wetlands Stream/Buffer Restoration Curb cuts/level Spreaders Shade Valley Wet Pond Design City of Charlotte, NC (image from Google) Big Warrior Creek Stream Restoration Wilkes County, NC Fletcher Park Wetland City of Raleigh, NC

27 BMP Siting and Prioritization Plan Unforeseen/Negative Site Factors Site Meets Minimum Criteria Field Assessment Desktop Feasibility Assessment Apply minimum Siting Criteria Viable Site Site does not meet Minimum Criteria Initial BMP Site Selection Eliminate Site Eliminate Site Preliminary BMP Design Calculate Pollutant Loads Calculate Probable Cost

28 Candidate Site Selection Proposed Stormwater Wetland Convert open space to stormwater wetland Daylight existing 42 stormwater pipe

29 Study Results Summary of BMPs Sited 51 Candidate Structural BMPs Identified in Study Area 21 Wetlands 10 Stream Restoration Sites 6 Level Spreaders Vegetated Filter Strips 13 Wet Ponds 1 Dry Pond

30 Recommended Management Plan Identify Key Quantitative and Qualitative Factors Quantitative Factors: Pounds of TN and TP removed Construction cost O&M cost Annual cost per pound of TN and TP removed Qualitative Factors: Property owner(s) Proximity to critical water/environmental features Permitability Public response

31 Incremental Benefit of Ranked BMPs Installing the first 39 BMPs would remove 234,460 lbs of TN Remaining 12 sites would only remove 6,690 lbs of TN

32 Study Results Let s Talk Money To install the first 39 most cost effective BMPs, the total cost (capital + land + 20 yr O&M) is $27,000,000 Total Project Cost (capital + land + 20 yr O&M) for 51 Candidate BMPs is $38,000,000 Installing all 51 candidate sites achieves a 6% reduction in TN and 8% reduction in TP.

33 Study Results Let s Talk Money City of Greensboro currently dedicates $1.5M to stormwater capital improvement projects ($500K for water quality improvement projects) Schedule forecast: $500K per year = 76 years to fund $38M $1.5M per year = 25 years to fund $38M $38M achieves only achieves a 6% reduction! Current economy reduces possibility for staff increases, stormwater fee increases, and tax increases.

34 Outline Introduction: Water Quality Impairments Resolving Water Quality Impairments Nutrient Management Strategies Neuse Tar Pamlico Falls Lake Jordan Lake A BMP Siting and Prioritization Plan Greensboro, NC Conclusions

35 Conclusions Nutrient limitations are coming: Jordan Lake Nutrient Management Strategy Falls Lake Nutrient Management Strategy High Rock Nutrient Management Strategy (currently on hold) Chesapeake Bay TMDL Florida Numeric Nutrient Rules EPA is now encouraging all States to set numeric nutrient criteria (per March 16, 2011 letter from EPA) Be proactive and prepare for the water quality rules that already, or may soon, affect you!

36 Thank You! Questions? Jacquelyn K. Corbin, E.I.T Water Resources Engineer CDM Smith Phone:

37 Existing Development Agriculture New Development Existing Development Riparian Buffers Wastewater Discharger

38 Introduction: Brief History of Water Quality Impairments * For waters with multiple classifications- only the first classification listed is shown above.

39 Introduction: Brief History of Water Quality Impairments Clean Water Act (1972) All waters in the US have a designated use Waters that cannot support their use are listed as impaired (303d listed). Each state must monitor water quality, and Update 303d listed waters every 2 years

40 Summary of Study Area BMP Costs Jordan Rules for Existing Development

41 Preliminary Site Evaluation Calculate Pollutant Load Removed Size BMP using NCDWQ BMP Manual Calculate pollutant loads using the Falls/Jordan Lake Stormwater Nutrient Load Accounting Tool (BMP Median Effluent Concentration approach) Jordan Rules for Existing Development

42 Preliminary Site Evaluation Calculate Conceptual Opinion of Probable Cost Calculate conceptual opinion of probable construction and 20 year maintenance costs Include land cost Include factor for other costs, such as engineering, legal, staff time, etc. (e.g. 50%) Jordan Rules for Existing Development

43 Cost Equations Utilized Jordan Rules for Existing Development

44 Nutrient Generation and Reduction Jordan Rules for Existing Development

45 Preliminary Site Evaluation Calculate Contributing Pollutant Load As of 09/2011, NCDENR has not determined what method to use for calculating pollutant loads from existing developed areas Falls/Jordan Lake Stormwater Nutrient Load Accounting Tool, developed by NC State University in coordination with NCDENR, provides tool for comparing performance of BMPs. Jordan Rules for Existing Development