Coastal Resiliency: The Role of Data in Improving Shoreline Protection

  GIS, Waterfront

Living Shoreline community efforts in Norfolk, VirginiaThe following post explores a successfully-implemented living shoreline within the context of how data collection can drive better future decisions. “A GIS Forensic Look at an Implemented Living Shoreline Design for Coastal Resiliency” was originally presented by Dave Pryor and Kate Chaney at GIS-Pro and CalGIS 2018 in Palm Springs, CA.

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We live in a world where data defines much of our experience. In particular, how it’s collected and interpreted has meaningful impact for sustainability, sea level rise, and the resilience of the built environment. GIS has a significant role to play within this context – understanding pre- and post-project spatial information may alter and improve the design of everything from living and hardened shorelines to the siting of buildings and infrastructure.

In terms of resilience, the living shoreline is an attractive, effective, and cost-conscious approach to minimizing the impact of flooding and erosion along our coastlines. Below, we explore the role and variables of living shorelines and the potential contribution of GIS.

The Role of the Living Shoreline

“Living shoreline” is a broad term referring to a range of nature-based shoreline stabilization techniques that are intended to naturally mitigate sea level rise. Appropriate in low wave energy aquatic environments, these green solutions use primarily native materials to decrease wave energy, protect the shoreline, and prevent erosion in the event of storms or flooding.

The maintenance, restoration, or creation of living shorelines provides benefits beyond storm resilience as well – they are natural ecosystems that establish habitats for plants, fish, and animals, improve water quality, and provide carbon sequestration. In contrast with bulkheads or “hardened” shorelines, which are most appropriate in a setting like a port or heavily industrial waterfront where operations happen right next to the water, living shorelines use varying degrees of natural features to reduce wave energy impacting the shore.


Coastal Shoreline Continuum & Typical "Living Shorelines" Treatments

A breakwater slightly off shore reduces wave energy on the shoreline, while a combination of grading and flora work together to allow the shoreline to adapt to sea level rise. The tidal pool created by the breakwater flows into a near-shore portion, which has a wet/dry cycle with the changing tides. The slope and selected marsh grasses take out additional wave energy on the remainder of the shore and lead to the upland area, which is unlikely to be flooded except during a storm surge.


The cost-effectiveness of living shorelines makes them particularly appealing in coastal areas with many tributaries. They can frequently be installed with primarily volunteer labor, which not only minimizes the project cost but also positively contributes to the community’s sense of ownership.

Case Study: Colley Bay Living Shoreline

Installed in 2012, the Colley Bay Living Shoreline was a first for the City of Norfolk, VA. Completed on both sides of the Lafayette River, one side fronts a school and park area, while the other fronts a number of private properties. Accordingly, the designs feature different elements and levels of sophistication. In front of the school and park, walkways, benches, a planned pier, a living classroom, and a reed grass management area promote community and educational use. In front of the private properties, a simpler living shoreline protects property values.

From a GIS standpoint, a forensic look at the Colley Bay Living Shoreline focuses on what kind of data was initially collected, whether or not the living shoreline has been effective, and how the design could be improved in the future. An aerial photo from 1939 provides the primary geographic information used during the design and construction of the project. Kate Chaney, curious about the shoreline conditions and change over time, digitized the shoreline in aerials from 1939, 2009, and 2018.


A living shorelines progression through time by examining the timeline of photogrammetry.

As the digitized shorelines demonstrate, the shoreline has changed over time. In at least one regard, the Colley Bay Living Shoreline is a resounding success – pictures from 2014 to 2018 demonstrate the significant plant growth and maturation that’s taken place. In one photo, the plant life is so vibrant that the view from a bench integrated during the living shoreline’s construction is virtually obscured.


Ultimately, the importance of collecting GIS data pre- and post-project is about designing better, more effective infrastructure projects. While the living shoreline serves as this case study, the value of data centers on its ability to help us visualize both immediate action items and the bigger picture. In the case of a living shoreline, GIS data may contribute to securing future grant funding – a priority for any coastal municipality. In another scenario, this data could be used to track economic growth by assessing development near an improved intersection; it can impact decisions about housing, population movement and growth, and future demands on the transportation system; it can inform the need for flexible use spaces; and much more.

By defining early on the type of data you need, why it’s important, how it can be collected, and how it can contribute to future analysis, a vision and plan for that data can be established. In turn, this data will facilitate infrastructure design that better serves its communities now and in the future. When viewed in the context of both the human experience and environmental sustainability, the role of GIS in improving design solutions over time cannot be overlooked.


About the Authors

Dave Pryor, PE, leads our waterfront and coastal engineering practice. With more than three decades of experience, he is focused on guiding clients through critical projects impacted by resiliency, sea level rise, and the global economy. To speak with Dave, please call 757.455.5800 or email dpryor@clarknexsen.com.

Kate Chaney, GISP, is a senior GIS analyst with more than 17 years of experience in her field. In addition to leading suitability analyses, site assessments, environmental and biological habitat studies, and numerous plans related to flooding, Kate specializes in helping her clients utilize data to achieve their goals. To learn more about our GIS practice or to speak with Kate, please call 757.455.5800 or email kchaney@clarknexsen.com.