New York City Salt Marsh Restoration and Protection, Post-Hurricane Sandy
Total Page:16
File Type:pdf, Size:1020Kb
2017 New York City Salt Marsh Conference Restoration and Protection, Post-HurricaneSandy Sandy ChristopherStorm Haight, Marit Larson, Rebecca Swadek, and Ellen K. Hartig SuperNew York City Department of Parks & Recreation Forestry, Horticulture, and Natural Resources Super Storm Sandy: Five Years Later Meadowlands Conference October 26, 2017 2017 Conference Sandy Storm Super Title of Presentation Goes Here 2 Urban Coastal Wetlands • Coastal wetlands are a critical part of a livable NYC o Resilient coastal natural areas o Aesthetic, recreational and educational value2017 o Ecosystem services (fisheries, bird communities, water quality) • Coastal wetlands are at riskConference o Sea-level rise and storm surge Sandy • Planning, management and restoration can help protect our wetlandsStorm for the future Super Project Goals • Assess current condition of natural marshes 2017 • Evaluate vulnerability to sea- level rise (SLR) Conference • Identify opportunities for protection, conservation &Sandy restoration Storm Super Prioritize restoration & protection opportunities Ecological Assessment at 25 salt marshes across NYC Desktop Analysis o Historic Loss Analysis Long Island o Sea Level Affecting 2017 Sound Marshes Model (SLAMM) Rapid Ecological Assessments Conference o Mid-Atlantic Tidal Rapid Sandy Assessment Method (MidTRAM) Storm Jamaica Bay o NAC Salt Marsh Assessment (NACSMA)Super Staten Island Conditions and vulnerability indices Marsh Loss Analysis • 1,011 acres were Alley Creek, Queens assessed • 160 acres, or 18 Long Island Sound percent of salt marsh 2017 was lost in the waterward direction (shoreline, ditch, creek) between 1974- Conference 2012 • Alley Creek lost 12 Sandy acres or 23% Storm Super 6 Site Scores: Condition and Vulnerability Saw Mill Creek Outer: Condition Saw Mill Creek Outer: Vulnerability Marsh Area Marsh Area Percent Developed Native Species Richness Potential Marsh Loss to SLR Total Vegetated Cover Potential Marsh Gain from Migration Low Marsh Soil Strength Trend in Waterward Marsh Loss Salt Marsh Breeding Bird Count Bare Peat Coverage Edge Density Trend in Pool Size Percent High Marsh2017 Ditch Density Total Score Total Score -2 -1.5 -1 -0.5 0 0.5 1 1.5 -1.5 -1 -0.5 0 0.5 1 1.5 Z-Score Z-Score Conference Sandy Lemon Creek Outer: ConditionStorm Lemon Creek Outer: Vulnerability Marsh Area Percent Developed Marsh Area Native Species Richness Super Potential Marsh Loss to SLR Total Vegetated Cover Potential Marsh Gain from Migration Low Marsh Soil Strength Salt Marsh Breeding Bird Count Trend in Waterward Marsh Loss Bare Peat Coverage Edge Density Trend in Pool Size Percent High Marsh Ditch Density Total Score Total Score -2 -1.5 -1 -0.5 0 0.5 1 1.5 -1.5 -1 -0.5 0 0.5 1 1.5 Z-Score Z-Score Higher Condition / Lower Vulnerability0.8 Higher Condition / Higher Vulnerability W. T. Davis Outer Priority site for Alley Creek Inner protection 0.6 Long Island Sound Four Sparrow Pelham Bay Cove Richmond Creek Jamaica Bay 0.4 Saw Mill Creek Inner Saw Mill Creek Outer Hutchinson Inner Staten Island 0.2 Turtle Cove Neck Creek Inner 2017 Udall's Cove Marsh 0 -1.5 -1 -0.5 0 0.5 1 1.5 2 Alley Creek Outer W. T. Davis Inner Hutchinson Outer ConferenceNeck Creek Outer -0.2 Idlewild Marsh Inner Lemon Creek Inner Fresh Creek Marsh Condition SandyFresh Kills Marsh Arlington Marsh -0.4 Spring Creek Storm Westchester Creek Super -0.6 Pugsley Creek Marsh Idlewild Marsh Outer Lemon Creek Outer -0.8 Priority site for restoration Lower Condition / Higher Vulnerability Lower Condition / Lower Vulnerability-1 Vulnerability Opportunities for Restoration and Protection Targets Threats Actions Obstacles to Acquisition/ Marsh Migration 2017Transfer Long Term Restore flooded Reduced Capacity Viability & Conferencehard surfaces for Vertical Function Growth of NYC Sandy Increase Marsh Saltmarsh Surface Elevation in Study StormErosion and Area Decreased Size Super Restore Eroded Marsh Edge Marine Debris Large Scale Marine Debris Removal Acquisition/ Restore flooded Transfer hard surfaces Future flooded hard surfaces All Sites (25) Current Future Parking Lots* = 29 ac Owner Marsh (ac) Marsh (ac) Roads** = 7 ac NYC Parks 864 +204 Other Hard Surfaces = 6 ac 2017 Private 21 +29 Total = 42 ac Other 37 +24 * Mostly Orchard Beach parking lot in Pelham Bay Park Govt. **Includes Brookville Blvd. in Queens and Travis Ave in 300 ConferenceStaten Island 250 200 Sandy 150 Storm 100 Size (acres) 50 Super 0 Private Public Property Type Additional Future Wetland Current Wetland Non Wetland Area in Parcel Future flooding in Pelham Bay Park, Bronx Increase Marsh Surface Elevation 10 8.9 8 6 4.8 4 2.1 2017 2 0.7 0.7 0 Idlewild Lemon Spring Idlewild Turtle Priority Area (acres) Priority Marsh Creek Creek Marsh Cove Outer Outer Inner Conference Sandy Storm Super Photo: Patty Doer, TNC-NJ Idlewild, Queens Field Data Desktop data: • % low marsh • Future marsh loss (SLAMM) • % bare ground • Accessible for sediment • Breeding birds placement Restore Eroded Marsh Edge 10 8.4 8 5.7 5.6 6 4 2.7 1.5 1.5 2 1.2 1.2 0 2017 Priority Area (acres) Priority Alley Creek Loss Conference Analysis 1974- 2012 Sandy Storm Super Alley Creek, Queens Desktop data: • High area, width, and % marsh loss (1974-2012) • Future marsh loss (SLAMM) • Accessible for sediment placement Large Scale Marine Example Site: Four Sparrow Marsh, Brooklyn Debris Removal Before Before 2017 Conference Sandy After After Storm Super 13 Recommendations • Pilot new approaches to wetland protection and restoration: Shoreline protection and waterward restoration 2017 Elevation / sand enhancement • Continue debris removal Conference Marsh loss at Idlewild, Queens • Protect future marsh migration areas (reduce impervious area Sandyin parks, use existing regulations, acquisition, easements)Storm • Expand assessmentSuper approach to include non-Parks properties Clean-up in Four Sparrow, Brooklyn Towards a Salt Marsh Management Report for NYC • http://naturalareasnyc.org/in-print 2017 Conference Sandy Storm Super Interior Marsh Restoration in Alley Pond Park, Queens Goal: Restore salt marsh area lost to interior marsh pond expansion Approach: • Coir logs placement to form new edge • Sand placement behind coir into expanded pool 2017 • Volunteer planting Conference Sandy Storm Super 16 Thin Layer Sediment Application in Idlewild Park, Queens Goal: Increase salt marsh surface elevation to improve salt marsh sparrow habitat and resilience to SLR Approach: • Thin layer sediment application (10- 20cm in depth) onto existing low marsh and depressions 2017 • Monitor salt marsh sparrows Conference Sandy Storm Super 17 Reinforced Shoreline Project in Alley Pond Park, Queens Goal: Restore eroded marsh and establish a reinforced shoreline edge Approach: • Sand placement and planting in eroded area • Establish a front facing armored toe 2017 or breakwater structure on restored marsh edge (e.g. oyster castles, reef balls, coir log) Conference Sandy Storm Super 18 Acknowledgements NYC Parks - Natural Resources Group The Nature Conservancy Marit Larson Nicole Maher Rebecca Swadek Stephen Lloyd Ellen K. Hartig Lauren Alleman 2017 Novem Auyeung Jennifer Greenfeld Funding from U.S. EPA Region 2, Wetlands Protection Program Conference Natural Areas Conservancy Development Grant Helen M. Forgione Kathleen Drake Sarah Charlop-Powers Sandy Bram Gunther Storm Super Contact: [email protected] .