Parcel-Scale GIS Analysis to Support Nearshore Restoration and Outreach

Nearshore restoration opportunities can be identified with spatial data at many different scales. Linking assessment data with individual parcels provides a foundation to address one of the most common constraints to restoration implementation – the landowner. Spatial analysis of site conditions at the parcel unit scale can be used to filter out parcels in which restoration is infeasible or would provide little benefit to the nearshore ecosystem. The outputs of these types of analysis can be used to develop highly relevant outreach materials to targeted landowners and neighborhoods, incentives for property owners, and inform restoration design. This poster demonstrates the details of how parcel-unit GIS analysis was used in two different projects in the Salish Sea to identify and prioritize nearshore restoration opportunities, especially the removal of shore armor in low-risk sites. New opportunities and site synergies were discovered, resulting in targeted outreach and showcase pilot restoration projects. Protection priorities and parcels in which soft shore protection were viable alternatives to shore armor were mapped in one of the studies. This poster explains the analysis process and elaborates on the successes of two projects: The Feeder Bluff Restoration Assessment for Island and East Jefferson Counties project, and the Port Susan Marine Stewardship Area Armor Removal Assessment. Integrating science and social data can help to prevent scientists and managers from working in a bubble and provide the interaction necessary to initiate projects by scientifically identifying appropriate sites and building partnerships with willing landowners for nearshore restoration

Decision tools for sea level rise adaption in San Juan County: Connecting the dots between shoreform response and vulnerability to identify appropriate adaptation approach.

Gaining public awareness and technical resources are critical first steps towards climate change adaptation. San Juan County is comprised of over 420 miles of shoreline and over 4,600 privately owned waterfront parcels. Many of these shores comprise valuable habitats that provide the ecosystem processes, structure and functions upon which the marine food web depends. The lack of major population centers in San Juan County and the relatively rural character of the islands provide a unique opportunity for adaptation to sea level rise within a context with far fewer constraints than more urban shores. Coastal Geologic Services (CGS) has been working with Friends of the San Juan’s over the past several years to develop sea level rise planning tools for the County including a Sea Level Rise Vulnerability Assessment of San Juan County. Most recently CGS has introduced a series of decision tools (with supporting graphics) that help shoreline property owners understand how different shoretypes will naturally respond to sea level rise, the sources of vulnerability most likely to affect their shores, and the range of adaptation options for various shoretypes and levels of vulnerability. Making these connections is critical as there is a broad spectrum of shoretypes and a wide range of vulnerability across the county. Therefore there is no uniform approach or recommendation that can be applied county-wide. These tools enable property owners to identify a suite of appropriate adaptation options that fit the needs of their property. Various adaptation options are described in the project report including the costs and benefits associated with each option. These guidance materials were developed with the premise that informed decisions are better decisions and shoreline property owners are increasingly ready to move ahead with adaptation strategies

Sea Level Rise Vulnerability of San Juan County, Washington

The objective of this study was to attain greater understanding of the areas within San Juan County that are vulnerable to implications of sea level rise. The resulting countywide mapping tool highlights areas potentially at risk of both inundation and erosion, for which management strategies can be developed to reduce, avert, and mitigate these SLR impacts. Inundation modeling was paired with bluff recession estimates across two SLR scenarios (moderate, high) and planning horizons (2050, 2100). Inundation mapping was conducted by linking local topography data (LIDAR) to tidal datum and elevations for each scenario and planning horizon. Inundation areas were mapped between MHHW, the highest observed water level, and each of the scenarios and planning horizons. Bluff recession estimates were developed based on a stratified sample of background erosion/change rates from different geomorphic shoretypes in the county. Change rates were measured using historic air photo analysis and digital shoreline analysis systems (DSAS). Historic recession rates were used to project future bluff recession (with accelerated recession rates based on rate of sea level rise), across the two scenarios and planning horizons. Projected bluff recession estimates were buffered from the bluff crest to map vulnerability areas. Roads and structures located within vulnerable areas were highlighted to facilitate adaptation planning. Results identified 19 miles of vulnerable roads (11.1 miles of which were county roads) and over 1,300 vulnerable structures. Together these tools can form the foundation for the development of a SLR adaptation strategy for San Juan County and increase the effectiveness of existing management approaches. In addition, these results can be used to identify additional long-term restoration and conservation targets throughout the County