Learning Objectives. Thinking about Tomorrow s Waterfront Parks Lessons from Hurricane Sandy and Beyond. Hurricane Sandy

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1 Learning Objectives Thinking about Tomorrow s Waterfront Parks Lessons from Hurricane Sandy and Beyond Presenters Peter Kelley, ASLA, James Koth, ASLA, Jeffery Sandgrund, Brooklyn Bridge Park Andrew Lavallee, ASLA, AECOM 1. Learn about the types of storm damage that occurred at two recently designed and constructed waterfront parks during Hurricane Sandy. 2. Discover which design strategies proved resilient to tidal surges and subsequent flooding and which were unsuccessful. 3. Understand the challenges of storm mitigation strategies and their impact on future capital and maintenance costs. 4. Learn how the storm has changed programming and operational priorities and how landscape architects might apply these in future designs. Sandy and a Tale of Two Parks: and Brooklyn Bridge Park Hudson River Park Hurricane Sandy Hudson River Park Brooklyn Bridge Park Brooklyn Bridge Park 1

2 Hurricane Sandy Owner: Trust Site: Const.: 54 Acres Upland Park, 36 Acres Piers, 460 Acres water area 5 miles long North to South 1999 to Present Master Plan: Signe Nielsen / Quennell Rothschild JV Segment Designers: Abel Bainson Butz Landscape Architects Richard Dattner Architect/MKW Landscape Architects, JV Michael Van Valkenburgh Associates Landscape Architects Mathews Nielsen Landscape Architects Image S ource: Climate Central 2

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6 Brooklyn Bridge Park Brooklyn Bridge Park Owner: Brooklyn Bridge Park Development Corporation Site: 130 Acres, 94 Acres Upland Park, 36 Acres Piers 1.7 miles long east to west Designer: Michael Van Valkenburgh and Associates, Inc. Image Credit: MVVA 6

7 Topography 7

8 Stone Shoreline Stabilization Stone Shoreline Stabilization 8

9 Lessons Learned What worked? Areas that were elevated above the flood elevations suffered little damage Sand-based soils that flooded drained rapidly allowing saline intrusion to diminish rapidly Plant selections chosen for sea-side conditions appear to have withstood saline inundation Railing designs with horizontal members or flexible mesh in-fill panels withstood impacts of water driven debris or allowed it to flow through with minimal damage Waterfront structures including piers, bulkheads and stabilized shorelines withstood tidal surges with minimal damage Rigid pavements and decking withstood flood water damage Building finishes generally withstood flood waters and were easily cleaned and sanitized Lessons Learned What didn t work? Lightweight fill (styrofoam blocks) over pier deck structures became bouyant and lifted paving and other materials on top In-fill synthetic turf carpets on pier structures in many cases floated and displaced when flooded Loose-laid surfacing such as stone dust and sand eroded Utility penetrations through bulkhead walls created openings through which fill materials washed out Thru-deck drains with backflow prevention in the pier deck structures failed under tidal surge pressures, allowing fill material to wash out Lessons Learned What didn t work? Electric utilities set at or within 4 feet of the code required 100 year flood elevation (10.0) suffered extensive damage Lighting systems Communications systems Irrigation systems Conduits buried below grade trapped water since they were not designed to drain Electrical splice boxes at or below flood elevations lead to extensive cable failures Multiple systems controls through out the park made rapid powering down a challenge 9

10 Future Strategies Utilizing Risk Assessment as a Design Driver Understanding risk and developing a realistic consensus about future costs (especially for publicly funded parks) Assessing adequacy of flood elevations in terms of code requirements and likelihood of future events Identifying types of storm risks (waves, flooding, power and utility outages, restricted access, lost revenue, etc) Using risk assessment to set limits on value engineering challenges during design process Future Strategies Design Strategies for Infrastructural Resiliency Using multiple flood elevations Finish Floor Elevations (FFE) Utility and Equipment Elevations Wet flood proofing versus dry flood proofing Current and future technologies and their potential to minimize damage: solar and wireless Allowing water to move in and out Park scale Materials assembly scale Infrastructural elements and chases Future Strategies Design Strategies for Finishes Resiliency Adopting an aesthetic that is more in keeping with the realities of water s edge conditions plants, paving, shorelines, structures. Hard vs Soft Water Edges Keeping materials in place during surges and floods Protecting the utility infrastructures Successful Pavement Types Pier Structures Designs; program, elevation, materials Planting and Soil Strategies adapted to frequent inundation Future Strategies Waterfront parks are an important feature of our urban landscapes but they need to be carefully planned due their inherent risks It is not realistic or necessary to avoid parks in areas that will flood It is not always practical to design for infrequent or noah s ark storm events. There needs to be consensus about what is tolerable risk and future cost We cannot simply elevate our way out of the problem, especially within existing low-lying and high density communities Future costs of predictable storm damage should be built into capital and operating funding costs if our public investments are to be maintained 10