Waveland’s Climate-Informed Local Hazard Mitigation Plan Update
Waveland, Mississippi is a small town by the Gulf of Mexico. Many residents reside in areas less than 15 meters above sea level. Frequent floods and resulting costs of insurance rates and home repairs are driving residents out of the city. With a grant funded by FEMA and the Alabama-Mississippi Sea Grant, the City of Waveland hired the consulting firm AMEC Environment and Infrastructure (AMEC) to develop a hazard mitigation plan that followed the Disaster Mitigation ACT (DMA) planning regulations. The plan will better equip the City of Waveland facilitate risk-based decision-making and mitigate city vulnerability.
Waveland, Mississippi, is a small town located along the Mississippi Sound of the Gulf of Mexico. A majority of the municipality is less than 15 feet above sea level, and 90% of the municipal area is in a special flood hazard zone. Any event larger than a base flood (i.e. a flood with a one percent chance of being equaled or exceeded in any given year, also known as a 100-year flood), including rainfall-related flooding and storm-surge flooding, leads to neighborhood damage, and frequent floods are affecting home mortgages and flood insurance rates. Recurrent flooding is driving many residents out of the area, as they cannot afford to pay the increasing cost of flood insurance and keep up with repairs associated with flood damage. Waveland’s population has shrunk significantly since Hurricane Katrina.
In response to increasing flood risk and community vulnerability, the City of Waveland decided to update its 2007 Federal Emergency Management Agency (FEMA) approved hazard mitigation plan in order to better mitigate the risks of flood and other natural disasters, hoping that enhanced community safety would reduce resident migration. Updating the hazard mitigation plan would also maintain the city’s eligibility for federal disaster assistance, and earn the municipality credits under the National Flood Insurance Program (NFIP) Community Rating System (CRS), helping reduce insurance rates for homeowners and business owners.
The hazard mitigation plan update process was funded by a FEMA grant, and grant funds were matched by an in-kind grant from an outside party. Waveland also received a $34,000 grant from the Mississippi-Alabama Sea Grant Consortium to incorporate sea level rise and other climate change impacts into its plan update. Specifically, this grant allowed the city to hire a consulting firm with climate change experience to lead an analysis of how climate change may impact the city, and to link climate change with hazards identified in the hazard mitigation plan.
The hazard mitigation plan update process began in Fall 2012. Waveland hired AMEC Environment and Infrastructure (AMEC) to facilitate the plan update process and to help incorporate climate change impacts into the plan revision. Multiple local government and agency representatives were also engaged throughout the process via a Hazard Mitigation Planning Committee, which the city was required to form under the Disaster Mitigation Act (DMA) planning regulations.
The plan revision process followed DMA requirements and featured integration of FEMA CRS and Flood Mitigation Assistance Program (FMAP) planning principals, resulting in four phases: organize resources, assess risks, develop the mitigation plan, and implement the plan and monitor progress As a result, the planning process satisfied the requirements of six federal programs: FEMA’s Hazard Mitigation Program, Pre-Disaster Mitigation Program, the Community Rating System, Flood Mitigation Assistance Program, and Severe Repetitive Loss Program, and the U.S. Army Corps of Engineers flood control project criteria.
Phase 1, Organize Resources, involved setting up a process for the plan update, organizing the Hazard Mitigation Planning Committee, and engaging the public. The city passed a resolution forming the Hazard Mitigation Planning Committee and approving the established planning process, which was developed by AMEC, the fire department, and other city officials. To engage the public and other critical stakeholders, the city held a series of private and public meetings discussing the plan process and requesting feedback. For example, at the project kick-off meeting, members of the public provided input on how they would like to be involved in the process, and identified preferred methods of communication; they were then able to attend subsequent meetings and provide input on the draft report. Significant stakeholders, including county, state, and federal agencies and nearby municipalities, were also engaged to participate in meetings and different stages of the plan update. Community planning and hazard mitigation planning efforts among these different agencies and groups were also identified to ensure they would be integrated into Waveland’s final plan revision.
Phase 2 involved conducting a risk assessment to better understand the various hazards threating the City of Waveland. This phase consisted of identifying potential hazards, gathering available information and modeling on each hazard, conducting a vulnerability assessment to understand future risk, and assessing the city’s capacity to implement hazard mitigation activities. To facilitate this process, AMEC distributed worksheets to the Hazard Mitigation Planning Committee and other regional stakeholders to gather information on past and current hazards, existing city capabilities and values, and to identify potential response actions. Via another worksheet, AMEC also evaluated progress on mitigation activities identified in the 2007 hazard mitigation plan. Worksheet information and input from HPMC meetings were used to identify known and potential major hazards, nine of which were not assessed in the previous hazard mitigation plan, including climate change (sea level rise and storm surge), flooding, and drought.
Once these hazards were identified, AMEC searched the scientific literature and available agency databases, and used a variety of available tools and GIS to gather relevant information, including past occurrences and future projected trends. This information was overlayed with city data (e.g., housing distribution, facility locations, cultural, historic, and natural resources locations, population trends, land use) to model future vulnerability, which for each factor was ranked on a scale from Extremely Low to Extremely High. Finally, AMEC conducted a capacity assessment, evaluating the various plans, ordinances, and partnerships available to the city that could be used to implement hazard mitigation activities.
Climate change was explicitly incorporated as a hazard for the City of Waveland, but plan authors also identified how climate change may interact with other hazards, such as coastal bank erosion and dam and levee failure. Climate information and projections for the report were sourced from a variety of peer-reviewed state and federal reports. AMEC also used several available climate tools to incorporate site-specific projections and help visualize potential climate impacts on city resources. For example, it utilized the NOAA Sea Level Rise Viewer to model sea level rise of 1 foot (best case), 3 feet (average case), and 6 feet (worst case), overlaying these projections with GIS files of city infrastructure. The Sea Level Rise Viewer was also used to visualize how storm surge may change with different sea level rise scenarios. In addition, AMEC utilized the National Weather Service’s Sea, Lake and Overland Surges from Hurricanes (SLOSH) model to calculate potential storm surge associated with hurricanes in the absence of sea level rise. AMEC also used the U.S. Drought Monitor to demonstrate drought trends in the city and broader region and obtained flood and hazard information from Digital Flood Insurance Maps and Flood Insurance Rates Maps.
After identifying future hazard risk, Phase 3 focused on developing the updated mitigation plan. A series of meetings with the HPMC was used to review and update the major goals of the mitigation plan, as well as identify and analyze potential mitigation actions to address key hazards. Only hazards deemed to be high risk during the risk assessment stage were considered for action development, including: climate change (storm surge/sea level rise), coastal/canal bank erosion, floods (100/500 year floods and localized flooding), hurricanes/tropical storms/storm surge, thunderstorms, and hazardous material release from railroads. The draft plan was circulated for comment, and the final version was published and adopted by the city in 2013.
Outcomes and Conclusions
In general, by identifying key hazards and future risk, Waveland’s local hazard mitigation plan will facilitate risk-based decision-making to mitigate city vulnerability to both climate and non-climate hazards. The Waveland community has been very receptive to the plan revision process and different component projects. The final plan is posted on the city’s website and on social media, allowing residents to have open access.
Since plan publication in 2013, the City of Waveland has begun to implement priority projects and actions to mitigate municipal risk. For example, the city is identifying the most flood-prone zones, and since 90% of the city lies in a special flood hazard area, the city is implementing a $6.9 million drainage project aimed at improving floodwater drainage. While initial steps toward risk mitigation are promising, city officials anticipate that limits on staff capacity and funding will be among the major barriers to implementing key actions identified in the plan.
Reynier, W., & Gregg, R.M. (2017). Waveland’s Climate-Informed Local Hazard Mitigation Plan Update [Case study on a project by the City of Waveland]. Product of EcoAdapt's State of Adaptation Program. Retrieved from CAKE: http://www.cakex.org/case-studies/wavelands-climate-informed-local-hazar... (Last updated December 2017)