HomeMy WebLinkAboutCoastal Resiliency Milone_Macbroom presentationTown of Nantucket Select Board Meeting, 4/28/2018 | Nantucket, MA
Town OF Nantucket
COASTAL RESILIENCE Plan
Overview and Progress Update
David Murphy, P.E., CFM, Milone & MacBroom, Inc.
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Agenda
▪Why Develop a Coastal Resilience Plan?
▪Scope of Services
▪Potential Outcomes
▪Next Steps
▪Agenda for Public Charrettes
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Event!Recovery
Greatest Loss
Event!
Greatest Loss
Improved
Recovery
Adapt
Prepare
Initial
Recovery
Less Damage
What is Resilience?
▪Resilience:
resist, absorb,recover, adapt
▪Traditional “hazard mitigation”
▪Recovery
▪Long term, changing conditions
▪Flexible “normal conditions”
▪Coastal Resilience:
▪sea level rise
▪shoreline change
▪Increasing magnitude and
frequency of storm events
Quality of LifeTime
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Why a Coastal Resilience Plan?
▪Comprehensive Plan to Make Shoreline More Resilient
▪System-Wide (entire Town,not just specific spots)
▪Break down silos (planning, DPW, EM, etc)
▪Consolidate diverse documents & efforts
▪Specifically address coastal impacts of climate change such as
shoreline change, erosion, and flooding as sea level rises
▪Strengthen position for funding
▪Hazard Mitigation Plan
▪Highly Prescribed
▪Wide Ranging
▪Short Time Frame (5 years)
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Scope
Charrette
May 10, July 18
Jan •Review Existing Capabilities
Feb •Data Collection
March •Vulnerability & Risk Assessment
Apr •Review of Adaptation Options
May-Jul •Public Meetings & Surveys
July •Island-Wide Coastal Resilience Framework
August •Coastal Resilience Plan Document
August •Implementation Plan & Process
Online Survey
surveymonkey.com
/r/ACKCRP
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Daily High Tide
Chronic Storms
Major Storms
Entire Island
at Risk
Neighborhood
at Risk
Specific Site
at Risk
Risk = Vulnerability x Frequency
Scope: Risk & Vulnerability Assessment
Vulnerability: how susceptible to loss or damage?
Frequency: how often does the event happen?Frequency/Area of ImpactHighMedLowLow Med High
Vulnerability
Bluff
Erosion
Beach
Degradation
Bridge
Undermining
Downtown
Inundation
Erosion of
Wastewater
Treatment
Ponds
Debris
Blocking
Harbor
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Scope: Adaptation Options
•Retreat
•No shoreline protection
•Abandon vulnerable area
•Accommodation
•No shoreline protection
•Remain in vulnerable area
•Adjust structures,
infrastructure, land-use,
preparation & response
•Protection
•Shoreline protection
•Remain in vulnerable area
•No adjustment of structures,
infrastructure, land-use, etc.
Image: barrett-enterprises
Removal of Structures in Codfish Park
Elevation in Brant Point
3 General Types of Adaptation (IPCC, 1990)
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Scope: Adaptation Options
•Transportation Options
Elevate & Harden Roads & Bridges
Secondary Ferry Wharfs
•Shoreline Management
Living Shorelines, Sediment Management,
Bioengineered Banks
•Shore Protection Structures
Seawalls, Bulkheads, Revetments
•Building Elevation & Floodproof
•Directed Development
Rolling Easements, Migrate with Shoreline
•Hazard Zone Regulations
Development Limits, Building Standards
•Emergency Management
Satellite Facilities, Evacuation Plans Nantucket Harbor
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Possible Outcomes
•Roadmap for town-wide decision making
•Minimum design criteria considerations for future projects
•Prioritization of geographic areas to address in short-term vs.
long-term
•Ideas for maintaining town-wide tax base and levels of service
if they are lost to erosion or flooding
•If there is consensus to do so, identification of areas where
protection, accommodation, or managed retreat should be
the long-term goal
•Identification of the next steps for planning or design
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Public Charrettes
5:00 –5:15 Arrival
•Hand out comment cards & clickers
•Poster viewing
5:15 –5:40 Milone & MacBroom Overview
Presentation
•Project Overview
•Risk & Resilience Concepts
•Island Overview & Risks
•Resilience Options
5:40 –5:45 Questions & Discussion
•Clarifying points about presentation
5:45 –6:00 CZM Presentation
•What is CZM?
•Examples from Other Communities
•References to New Data
6:00 –6:45 Charrette
•Boards located around the room
•Attendees view posters, share thoughts, ask questions
6:45 –7:00 Debrief
•Review results of charrette as a group
•Floor is open to general questions and comments
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