Methodology : GBWC Resiliency Groundtruthing Application

The Greater Baltimore Wilderness Coalition identified a Regional Resilience Green Infrastructure Network. We integrated data from multiple sources and scales to identify an interconnected network of natural areas and other open spaces that provides a wide array of benefits to people and wildlife. This network includes the statewide Green Infrastructure hub-corridor network, but also county networks, regulated features, and other important natural resources. Areas of jurisdictional and priority overlap can highlight opportunities for collaboration and implementation, can help inform and support local plans, and help identify an appropriate level of protection for natural features that support long-term resiliency.

Local plans, regulations, policies, and programs can be used together to define and implement strategies for using green infrastructure to enhance community and regional resilience to coastal storms and climate change. Localities can use local comprehensive and functional plans to define goals, objectives, policies, and actions for using green infrastructure to enhance resilience. Regulatory tools allow localities to incentivize green infrastructure through the development review and approval processes, while other policy tools supplement adopted plans and regulations. Capital investments create opportunities to provide, enhance, or protect green infrastructure through direct public investments, and programmatic tools allow for investment in implementation. For more information on best practices for using green infrastructure to enhance resilience, please see the American Planning Association white paper entitled “Supporting a Regional Green Infrastructure Network through Local Policy and Action”.

We purposely cast a wide initial net, to identify all natural land cover and features that could maintain resilience and other ecosystem services, as well as opportunities for ecological restoration or creation of hybrid structures to improve resilience. From here, we ranked areas according to their relative importance for each of the five green infrastructure strategies. The Coalition convened a workshop for local planners on March 9, 2016 to solicit feedback on input data and weightings. Based on this feedback and data availability, we collected spatial layers, weighed them within each strategy, then combined them. Values vary from 0 to 100, with 100 being the top ranking areas and 0 the lowest.

Protect Natural Resources
Mandatory criteria	Not already protected Not paved or a building
State-designated ecological significance	Statewide Green Infrastructure Hub-Corridor Network Targeted Ecological Areas Significant for Biodiversity Conservation (BioNet Tiers 1-5) Natural Heritage Areas Wetlands of Special State Concern + 100 ft buffer
Watershed characteristics (DNR 12-digit watersheds)	Percent forest cover (more forest preferred) Percent impervious surface (<5%/5-10%/10-20%/>20%) Blue Infrastructure Priority Watersheds 100 foot buffers of Stronghold Watershed streams, trout bearing streams, streams feeding municipal drinking water reservoirs, and Tier II High Quality Waters (Forests of Recognized Importance)
County/Local Scale Resource Features	County green infrastructure plans (Howard, Montgomery, Prince George’s, and Anne Arundel) Wetlands + 100-foot buffer Surface waters + 100-foot buffer 1% (100 year) floodplains 2% (500 year) floodplains Forest patches with at least 1 acre of interior Blue Infrastructure Priority Watersheds Forest patches delineated within Baltimore ≥10,000 ft2 and >90 ft wide Forest corridors ranked by importance Highly erodible soils Steep slopes (>15%) Baltimore City Habitat Protected Areas Anne Arundel bog wetlands + 100 ft buffer
Population vulnerability	Number of people/mi^2 % Population with income below poverty (12mo) % Population of non-proficient English speakers % Population <18 or >= 65 years of age
Ecosystem service values	Stormwater Abatement Groundwater Recharge Air Quality Sediment and Nutrient Capture Carbon Sequestration

Enhance and Restore Tree Canopy
Mandatory criteria	Grass, shrub, or bare land cover (preferred); or paved surfaces other than buildings or roads (acceptable but less preferred) Not an existing wetland
Land ownership	Public ownership preferred Privately owned with easement acceptable but less preferred Privately owned with no easement least preferred
State-designated ecological significance	Statewide Green Infrastructure Hub-Corridor Network Targeted Ecological Areas Significant for Biodiversity Conservation (BioNet Tiers 1-5) Natural Heritage Areas Wetlands of Special State Concern + 100 ft buffer
Watershed characteristics (DNR 12-digit watersheds)	Percent forest cover (less forest preferred) Percent impervious surface (5-20% preferred) Blue Infrastructure Priority Watersheds 100 foot buffers of Stronghold Watershed streams, trout bearing streams, streams feeding municipal drinking water reservoirs, and Tier II High Quality Waters (Forests of Recognized Importance)
County/Local Scale Resource Features	County green infrastructure plans (Howard, Montgomery, Prince George’s, and Anne Arundel) Wetland buffers Riparian buffers 1% (100 year) floodplains 2% (500 year) floodplains Highly erodible soils Steep slopes (>15%) Baltimore City Habitat Protected Areas Anne Arundel bog buffers
Population vulnerability	% tree canopy in census tract Number of people/mi^2 % Population with income below poverty (12mo) % Population of non-proficient English speakers % Population <18 or >= 65 years of age

Implement Multi-Benefit Green Stormwater Infrastructure
Mandatory criteria	Identified using EPA criteria for bioretention, constructed wetland, dry pond, grassed swale, infiltration basin, infiltration trench, porous pavement, sand filter (both surface and non-surface), vegetated filter strip, and/or wet pond
Land ownership	Public ownership preferred Privately owned with easement acceptable but less preferred Privately owned with no easement least preferred
Potential for stormwater capture	Area of impervious surface draining to the site Presence/absence of existing BMPs Presence of older development (less likely to have stormwater structures)
Watershed characteristics (DNR 12-digit watersheds)	Percent forest cover (less forest preferred) Percent impervious surface (>10% most preferred, 5-10% less preferred)
Nutrient loading (SPARROW output by NHD catchment)	Non-point local nitrogen (TN) urban runoff Non-point local phosphorus (TP) urban runoff
County/Local Scale Resource Features	1% (100 year) floodplains 2% (500 year) floodplains Highly erodible soils Steep slopes (>15%)
Population vulnerability	Number of people/mi^2 % Population with income below poverty (12mo) % Population of non-proficient English speakers % Population <18 or >= 65 years of age

Protect Critical Infrastructure
Mandatory criteria	Within floodplain or storm surge zone Forested wetlands at least 120 ft wide preferred, then upland forest at least 120 ft wide, then other wetlands, then underwater grasses (SAV) with consistent coverage for at least 7 years from 2004-2014. There were no dunes or large oyster reefs in the study area. Near (within 250 m) critical infrastructure MEMA critical infrastructure sites (EOCs, fire stations, police stations, medical centers, schools) Wastewater treatment plants Power plants Hurricane Evacuation Routes Rail lines
State-designated ecological significance	Statewide Green Infrastructure Hub-Corridor Network Targeted Ecological Areas Significant for Biodiversity Conservation (BioNet Tiers 1-5) Natural Heritage Areas Wetlands of Special State Concern + 100 ft buffer
Watershed characteristics (DNR 12-digit watersheds)	Percent forest cover (more forest preferred) Percent impervious surface (<5%/5-10%/10-20%/>20%) Blue Infrastructure Priority Watersheds 100 foot buffers of Stronghold Watershed streams, trout bearing streams, streams feeding municipal drinking water reservoirs, and Tier II High Quality Waters (Forests of Recognized Importance)
County/Local Scale Resource Features	County green infrastructure plans (Howard, Montgomery, Prince George’s, and Anne Arundel) Wetlands + 100-foot buffer Surface waters + 100-foot buffer 1% (100 year) floodplains 2% (500 year) floodplains Forest patches with at least 1 acre of interior Forest patches delineated within Baltimore ≥10,000 ft^2 and >90 ft wide Forest corridors ranked by importance Highly erodible soils Steep slopes (>15%) Baltimore City Habitat Protected Areas Anne Arundel bog wetlands + 100 ft buffer
Population vulnerability	Number of people/mi^2 % Population with income below poverty (12mo) % Population of non-proficient English speakers % Population <18 or >= 65 years of age
Ecosystem service values	Stormwater Abatement Groundwater Recharge Air Quality Sediment and Nutrient Capture Carbon Sequestration

Defend the Coast: Preservation
Mandatory criteria	Not developed Not already protected Within coastal storm surge zone Existing natural features within storm surge zone (forest, wetlands, or underwater grass)
State-designated Blue Infrastructure shoreline segments	Blue Infrastructure Total rank, allocated to nearest natural features in storm surge zone
Maryland Coastal Resiliency Assessment	Habitat role in hazard risk reduction (High/Moderate/Low/None)

Defend the Coast: Restoration
Mandatory criteria	Not developed Within coastal storm surge zone
State-designated Blue Infrastructure shoreline segments	Blue Infrastructure Total rank, allocated to nearest natural features in storm surge zone
Maryland Coastal Resiliency Assessment	Shoreline hazard index

Defend the Coast: Enhancement
Mandatory criteria	Grass, bare earth, or open water the most appropriate, followed by paved surfaces other than buildings and roads. Within coastal storm surge zone
State-designated Blue Infrastructure shoreline segments	Blue Infrastructure Total rank, allocated to nearest natural features in storm surge zone
Maryland Coastal Resiliency Assessment	Shoreline hazard index

Green Infrastructure Identification and Ranking Approach

Green Infrastructure Components and Ranking

Protect Natural Resources

Enhance and Restore Tree Canopy

Implement Multi-Benefit Green Stormwater Infrastructure

Protect Critical Infrastructure

Defend the Coast: Preservation

Defend the Coast: Restoration

Defend the Coast: Enhancement