Portland Harbor Dredge and CAD Cell Project

South Portland City Council Workshop July 2, 2019

1. Introductions

2. Project Need

3. CAD Cell Overview 4. Dredge Overview 5. Permitting 6. Costs and Funding 7. Schedule 8. Discussion

Agenda

• Cities of Portland and South Portland • The Portland Harbor Commission • Maine Department of Transportation • Friends of Casco Bay • The Casco Bay Estuary Partnership • Pier and Marina Owners • Lobster and Fishing Community • The Waterfront Alliance • Maine Congressional Delegation

Project Stakeholders, Proponents and Collaboration

Why Dredge?

• Historic sedimentation has made portions of immediate waterfront unusable

• Sediments not suitable for offshore disposal

• Legacy contaminants in sediments impacting benthic community and water quality

All harbors needs dredging eventually

Aspasia Marina during an astronomically low tide

Why Dredge?

Why Dredge?

Over 900 Boat Slips Support multiple yards and boat service businesses

South Portland’s vessel berthing assets are a regionally significant resource for boating and access to the water

Dredge and CAD Cell Overview

• In 2008 Normandeau completed Alternatives Analysis. Additional alternatives evaluated as part of 1998 and 2013 Environmental Assessments for Portland Harbor Dredge.

• A CAD Cell is the most cost effective and environmentally sound disposal option.

Why a CAD Cell?

Normandeau 2008

CAD Cell Fundamentals

CONCEPT • Between 250,000

and 300,000CY • 3:1 Slope in sides • ~ 50’ deep below

current bottom

CAD Siting

Criteria Technical considerations (Average) 1. Technical feasibility (CAD construction) 2. CAD Construction Cost 3. Area available for CAD (square footage) 4. Operational efficiency (during use of the CAD) 5. Influences on cap integrity 6. Land title Environmental/Habitat/Fisheries (Average) 7. Mapped shellfish beds 8. Water Quality (MEDEP rating) 9. Tidal Wading Bird Waterfowl Habitat 10. Lobster fishery (greater the effort the lower the score) Permitting/Public Feedback/Public Uses (Average) 11. State and Federal Agency feedback 12. Public uses (proximity to residential/recreational uses) 13. Public feedback 14. Navigational impacts (Federal Channel, moorage…) Scoring

Stakeholder Meeting July 18, 2016

CAD Cell -49 MLLW (with 1FT OD to -50MLLW) : 278,810 Cubic Yard Capacity

9.5 acres 800’x (400-600’ wide)

Geotechnical Boring/Sub-Bottom Profiling

CAD Cell Site Conditions

Site Characterization January 2017 Lobster Survey December 2017

CAD RIM Suitability Suitability Determination Remaining 14,000 cubic yards Testing requirements

• Owner outreach and dredge feedback

• 32 pier/waterfront owners • Dredge footprints/volumes for

permitting and CAD sizing • Over half of current dredge

volume from South Portland

Target Dredge Areas

Dredge Site Conditions

Sample locations prioritized based on the following:

• Representative dredge depth • Location relative to CSO or

storm-water outfall/historical use

• Inner and outer portion of dredge area

• 30 vibracore locations • 15 composite samples

Sampling and Analysis

Vibracore Sampling

Eelgrass Surveys

Lobster Surveys

• Multiple permitting project meetings with agencies

• Umbrella permit by the Portland Harbor Commission for wharves and marinas

• CAD Cell permit through the City of Portland and South Portland

• Submerged Lands Dredge Leases

Applications

Project Costs and Funding

Up to 278,000 cubic yards of material Approximate Dredge Costs $15,000,000 Approximate CAD Costs $15,000,000 Funding Sources (assumed) Municipal Funds (Portland and South Portland) Tipping Fees – Private and Public State Transportation Bond Funds Federal “BUILD” Grant (TIGER) Federal Port Infrastructure Discretionary Grant

• Permit submittals- October 2019 • Permits received- May 2020 • BUILD grant application- July 2020 • CAD cell construction- winter 2021/2022

• Harbor dredging- 2022-2027

Project Schedule

Discussion/Questions