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Integrated Waterfront Cleanup and Marina Development in Bellingham, WA Tom Wang, P.E. WEDA Pacific Chapter – San Diego 2009. Project Overview. Port of Bellingham is managing an integrated cleanup, new marina construction and waterfront re-development project within the Whatcom Waterway
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Integrated Waterfront Cleanup and Marina Development in Bellingham, WATom Wang, P.E. WEDA Pacific Chapter – San Diego 2009
Project Overview • Port of Bellingham is managing an integrated cleanup, new marina construction and waterfront re-development project within the Whatcom Waterway • Cleanup Whatcom Waterway contaminated sediments • Cleanup ASB sludges • Establish new shoreline face for future development • Construct new small boat marina • Improve marine habitat and public access
Project Team • Anchor QEA • KPFF Consulting Engineers • Coast and Harbor Engineering • Wilson Engineering • BST & Associates
Project Site Key Areas Cornwall Landfill Port Terminal (BST) Log Pond (ASB) GP Pulp & Tissue Mill (GP West) GP Dock Whatcom Waterway Central Waterfront
Whatcom Waterway Consent Decree Dredging Capping • Dredge Areas • ASB • Outer Waterway • Cap Areas • Inner Waterway • ASB Shoulder • Chemical Dock • Log Pond Deep-Draft Sludges Removed Dredging & Capping of Multi-Purpose Waterway Central Waterfront Shoreline Cleanup
Waterfront District Framework Plan(4/20/09)* • Joint planning effort by Port and City • Upland development by Western Washington University • Focus on sustainable design, community needs and working waterfront * Plan is subject to modification based on continued technical evaluations and public input.
Key Integration Challenges ASB Cleanup • ASB dredge prism • Sludge dewatering method • Water and stockpile management Outer Waterway • Dredge prism design • BST underpier area and Log Pond transition • Residual management Inner Waterway • Engineered cap design (coastal modeling and propwash) • Shoreline transition areas Disposal • Landfill competition and escalating costs
Key Integration Challenges Marina Development • ASB berm design incorporates public access and habitat • Float layout • Landside development • ASB landside stormwater improvements Other Key Project Challenges • Coordinating nearshore and upland uses and infrastructure • Multiple stakeholders (WWU, City, Port, Existing Tenants) • Site stormwater temporary improvements • GP Mill Site development timing • Rail access and stockpile management • Need to significantly raise grades at GP Mill Site
ASB Typical Profile • Defining native layer (i.e., clean surface) difficult • Geophysical methods unsuccessful • Several direct measurement methods used and correlated against boring logs
Sludge Dewatering • Hazco and Boskalis conducted independent pilot studies • Centrifuge • Filter press • Belt Press • Geotubes • Stabilization • Elutriate and leachate testing
Waterway Areas with Special Issues BST Wharf Log Pond Transition Clarifier Bulkhead Area Maple Street
BST Underpier Area Partially-armored slope Current design concept Diver-assisted hydraulic dredging Thickness Est. Avg. 5 ft Backfill removal area Residuals Management Maintain wharf design condition
BST – Log Pond Transition Area Current conditions Wharf Condition Berthing Uses
BST – Log Pond Transition Area Design issues High subsurface concentrations Propwash and windwave exposure Need for larger armoring Steep slope complicates placement Armor placement constraints Overhead structures Impacts of placement to structure
Inner Waterway • Main channel area to be capped • Propwash is the critical design factor • Gravel layer as armor • Inner waterway slopes to be armored • Windwaves are critical design factor • Armor stone required in wave breaking zone
Inner Waterway Steep-Slope Areas • Design issues • Existing structures • Shoreline integration • Existing upland use • Waterway and upland future uses • Impacts of sloping fill to navigation • Narrow channel • Potential future maritime uses • Boat haul-out
Maple Street Bulkhead • Issues • Phasing of cleanup and upland improvements • Land and navigation uses Condition at -3 ft MLLW
Clarifier Bulkhead Condition at -3 ft MLLW • Issues • Clarifier structure remains for temporary construction use • Phasing of cleanup and upland improvements • Land and navigation uses
ASB Armor Stone Reuse Analysis Good Long-Term Stone Quality Unsuitable for Armor Reuse
ASB Armor Stone Reuse Analysis Good Long-Term Stone Quality Unsuitable for Armor Reuse
Marina Habitat Areas Notes: *Slopes will vary depending on location.
Numerical Modeling • Numerical modeling is critical to effectively assess constantly changing alternatives from Port and Stakeholder input • Base model set up to cover both remediation and development purposes • Wind wave impacts • Tidal circulation • Whatcom Creek discharge impacts • Propwash impacts • Sea level rise and tsunami effects
Stormwater Transitioning • Existing stormwater systems inadequate for future development • More than 80 acres require upgrades • Currently plumbed to discharge to ASB • Upgrades to be phased for future development • Stormwater design to transition to City responsibility in long term
Current Status and Schedule 30% design to be completed Spring 2010 Permit applications ~mid-year 2010 Bid advertisement ~mid-year 2011 Construction duration 3-4 years Consent Decree cost estimate Remediation $55 million Marina $23 million