As coastal areas become inundated by sea level rise, temperatures become warmer, and precipitation patterns change, strategies for site design and location of program elements may need to change as well. Strategies at the site planning and land use scale are commonly broken into the categories of protection (protecting vulnerable areas), accommodation (periodic flooding or other climate impacts permitted), and avoidance/relocation (avoiding or moving out of vulnerable areas).
Design strategies for dealing with flooding in coastal areas may include locating vulnerable uses outside of flood zones (or areas likely to be flooded), shoreline stabilization, site elevation, increased protection of shorelines and coastal ecosystems, and identifying floodable or temporary uses that can be located in vulnerable areas. Warmer temperatures will reinforce the importance of providing canopy cover and shade in open spaces. In general, land use patterns in vulnerable coastal areas may need to change to reduce exposure of human populations to storms, sea level rise, and other hazards. However landscape architects will still be hired to work on coastal projects and will need to consider how best to respond. A phased approach to adaptive land use and design as conditions change may be one way of addressing future vulnerabilities in these cases (the Galveston State Park project here is an example). The image below provides another concept for ways to consider vulnerability in coastal site design.
Source: Michael Volk
Results from our survey generally echo these concerns and ideas. In coastal projects, respondents indicated that land uses less likely to be impacted by flooding should be used nearshore and those that are more vulnerable (such as buildings) should be set back in anticipation of climate change. Many respondents felt that the use of vegetative stabilization, such as living shoreline strategies, was a very useful solution for shoreline stabilization but that shoreline hardening techniques may also need to be used (important considerations in the use of shoreline hardening techniques such as seawalls include the long term cost of maintenance and ecological impacts). Survey respondents also discussed the use of setbacks, relocation, and non-construction zones to reduce vulnerability while others felt that people should build on the coastline at their own risk. Others noted that the state economy relies on shoreline construction and that a cost/benefit analysis should be used to determine what land use types should be allowable in particular areas.
Tools
Pathfinder: Landscape Carbon Calculator | Landscape Performance Series
The Value of Green Infrastructure: A Guide to Recognizing Its Economic, Social and Environmental Benefits | Landscape Performance Series
Research
Brown, et al. (2015). Designing Urban Parks That Ameliorate the Effects of Climate Change
Hill and Barnett. Design for Rising Sea Levels
Reed and Stibolt. (2018). Climate-Wise Landscaping
Watson and Adams. (2010). Design for Flooding: Architecture, Landscape, and Urban Design for Resilience to Climate Change