Presenting the Great Marsh Coastal Adaptation (Resiliency ... · Great Marsh Resiliency Planning...

Presenting the

Great Marsh Coastal Adaptation (Resiliency)

Plan

Wayne Castonguay, Ipswich River Watershed Association

www.greatmarshresiliency.org

Project area: the Great Marsh and its coastal communities in MA

Photo credit: David Stone

The Great Marsh: an ecosystem that provides a host of benefits to our communities, including critical coastal protection

WHY? Weather-related hazards are enhanced by

climate change

Warming temperatures bring…

More powerful storms and sea level rise.

Climate Changes: What are the Impacts?

Ocean

Water

Changes

Number of

hot days

Precipitation

Changes

Drought

Sea level

rise

Precipitation

Changes –

Flooding

Seasonal

Changes

• Coastal erosion

• Flooding

• Salt water intrusion

• Changing habitats

• Invasive species

• Changes in crops

• Snow pack • Flooding

• Changes in crops

• Health risks

• Energy use

• Fires

• Water supply

• Stream flow

All blue slides provided by and credited to MAPC

For the Northeast United States: temperature increased by almost 2 degrees, between 1895 and 2011 (US National Climate Assessment 2014)

Blue Hill Observatory Annual Temperature, 1831-2008 Source: Michael J. Iacono (from MA Climate Change Adaptation Report 2011)

Temperature change: observed

www.mass.gov/service-details/climate-change-in-massachusetts-and-its-impacts

Projected Temperatures North Coastal Watershed (including Essex)

Temperature F°

Observed

Baseline

1971-2000

Predicted

2050s

Predicted

2090s

Annual temperature 49.69°F 52.4- 55.88°F 53.2-60.47°F

Days over 90 °

(days/year) 7.69 days 14.56-33.98 17.68-70.13

Days over 100 °

(days/year) 0.04 days .2-3.14 .28-12.57

Temperature change: predicted Temperatures are predicted to increase by 3.78° to 5.22°F by mid-century, and by 2.9° to 9.54°F by the end of the century, with greater increases in winter compared to summer. The frequency with which heat waves (three or more consecutive 90°F days) occur are expected to increase.

Source: Sea Level Rise: Understanding and Applying Trends and Future Scenarios for Analysis

and Planning, Massachusetts Office of Coastal Zone Management, December 2013.

Precipitation change: observed

For the Northeast United States: 71% increase in the amount of heavy rain events that fell from 1958 – 2012. Source: US National Climate Assessment 2014

For Boston area: 10% increase over the past 50 years

Precipitation change: projected North Coastal Watershed (includes Salisbury)

Parameter

Current

Conditions

(1971-2000)

Predicted

Change by 2050

Predicted

Change by 2100

Low High Low High

Annual Precipitation 45.31 inches 45.34 50.83 46.07 52.48

Annual Consecutive

Dry Days 17.01 17.16 19.58 17.21 19.75

www.mass.gov/service-details/climate-change-in-massachusetts-and-its-impacts

Sea level rise: observed

• Boston tide station

• Records from 1921-2016

• Equivalent to 11 inches in 100 years

Sea level rise: projected (Greater Boston Harbor)

Source: Sea Level Rise: Understanding and Applying Trends and Future Scenarios for Analysis

and Planning, Massachusetts Office of Coastal Zone Management, December 2013.

In summary, changes to our region include….

The goal of the Great Marsh Resiliency Planning Project is to help communities to: Develop adaptation strategies to address climate

impacts so that critical human and natural systems can continue to function effectively and be resilient in the face of climate-driven threats

Great Marsh Resiliency Planning Process

Year 1 Task forces formed Vulnerable community assets & concerns identified Community climate-vulnerability assessments & public workshops Year 2 Review all adaptation strategies Identify community asset-specific strategies Regional adaptation workshops Write coastal adaptation plan Year 3 Regional implementation workshops

with Municipal Task Forces and Community Meetings

Great Marsh Resiliency Planning

SALISBURY

Salisbury

• Northernmost coastal community in MA

• 15.4 sq. miles land area, 27% of which is Great Marsh

• 8,283 year-round residents

• Majority of the town’s infrastructure is located in two sections:

o Salisbury Beach

o Salisbury Square

Salisbury Beach at Broadway

Probability of Coastal Inundation in 2030 and 2070

(includes projected storm surge)

2030 2070

GIS-Based Vulnerability Assessments

Assessment of Barriers to Flow

High-Priority Assets Identified by the

Salisbury Resiliency Task Force Priority Asset Location Hazard Type

Salisbury Beach at Broadway East of Broadway, stretching 200ft

north and south

Erosion,

flooding

Route 1A (Beach Road) West of Broadway, stretching over 0.5

miles Flooding

Salisbury Barrier Beach 3.8 mile long beach from NH Border to

Merrimack River Jetty

Erosion,

flooding

Coastal Dunes

- East of southern end of Atlantic Ave

- East of Ocean Front South

- North of the Beach Center, east of

Central Ave

Erosion,

flooding

Low-lying residential areas

bordering the Blackwater River

salt marsh

9th Street south to Lewis Ave Flooding

North End Boulevard from Old Town Way to 18th street Flooding

Sewage Pumping Station 228 Beach Rd Flooding

Seawall @ First Street 32 1st Street Erosion,

flooding

Highest-Priority Assets Identified By The

Salisbury Resiliency Task Force

A1 Salisbury Beach @ Broadway

A2 Route 1A (Beach Road)

A3 Salisbury Barrier Beach

A4 Coastal Dune south of Broadway

Salisbury Beach

at Broadway

VULNERABILITIES:

• Erosion – chronic and storm-related

• Storm surge flooding

Photo Credit: Gregg Moore

Climate Adaptation Strategies: actions taken to build resilience and to adjust to climate impacts on society and the environment

Climate Adaptation &

Resilience Policy

Natural Solutions

Nature-Based & Hybrid

Gray Infrastructure

Great Marsh Regional Adaptation Strategies

#1 Adaptation Strategy:

Increase Natural Security

• Protect natural habitats

• Restore degraded natural habitats

• Replicate natural systems & cycles

in developed areas

Wetlands Reduce Flooding!

Coastal wetlands are estimated to have saved $625 million in flood damages during Hurricane Sandy.

- COASTAL WETLANDS AND FLOOD

DAMAGE REDUCTION Using Risk Industry-based Models to Assess Natural Defenses in the Northeastern USA

Natural and Nature-Based Strategies

Restore connectivity of river and coastal systems

Use living shorelines to stabilize shoreline edges

Protect and enhance shellfish reefs and beds

Protect and restore barrier beaches and dunes

Beneficially reuse dredged material

Restore submerged-aquatic vegetation

Protect and restore salt marshes

Facilitate marsh migration

Enhance land conservation efforts

Protect & enhance biodiversity

Natural Defenses

BEACHES & DUNES SALT MARSHES

RIVERS & FLOODPLAINS BIODIVERSITY

Land-use Planning and Policy

Update municipal policies

Prioritize low-impact development (LID) practices

Revise local wetlands protection bylaws and regulations

Move development away from the coast and wetlands

Create “freeboard incentive” for buildings

Use incentives (e.g. TDCs) to reduce risky development

Institute comprehensive water resources management

Natural Strategies

DUNE RESTORATION INVASIVE SPECIES

REMOVAL

SALT MARSH

RESTORATION RESTORE CONNECTIVITY

Landcons MAST here

Great Marsh Land Conservation

Policy Strategies

LAND-USE REGS

CLIMATE-SMART

DEVELOPMENT

WATER RESOURCES MGT.

POLLUTION CONTROL

Low-Impact/Climate-Smart Development & Retrofits

Revise Local Bylaws and Regulations

Outreach included:

Symposiums, posters…

brochures, maps…

… E-newsletters, local cable videos, press, websites, & social media

Need to incorporate climate projections into everyday discussions, decisions and planning, including economic

development

Great Marsh Restoration Partners

“Let’s face it, folks, this is just one more statement about the fact that it’s really important for us to put time,

money, and resources into resiliency and adaptability.”

On January 7, 2018, on WGBH radio, Governor Baker said it’s important to learn from storms like this, and make adjustments.*

*https://news.wgbh.org/2018/01/07/local-news/storm-flooding-raises-issue-coastal-resiliency

Photo credit: Abigail Manzi uploaded to MyCoast

Thank you. Questions?

www.greatmarshresiliency.org

Wayne Castonguay Ipswich River Watershed

Association wcastonguay@ipswichriver.org