Facing the Future: Resilient Broward Addresses Climate Change Impacts Head-On
As flooding and extreme heat upend life and business in coastal Florida, Broward County is developing a comprehensive resilience plan to understand future risks and prioritize needed adaptations.
At a Glance:
To confront the escalating risks of climate change in the region, Broward County, Florida, developed a Resilience Plan that evaluates the impacts of sea-level rise, groundwater-level rise/depleted storage, increased surge events, and increased precipitation intensity.
The Plan incorporates advanced modeling, risk and economic analyses to recommend adaptation strategies, strategic policy modifications, and $20 billion (public and private) in infrastructure investments.
The Plan results in significant economic benefits to the region, including over $20 billion of increased flood insurance coverage, $31 billion of increased real estate value, and $3.6 billion of average annual avoided property damage.
Effective stakeholder outreach was key to the planning process, including visualization and crowdsourcing tools to inform decision-making and build consensus.
A Call to Action
On April 12, 2023, over 25 inches of rain fell in parts of Broward County, Florida, setting a state record and causing catastrophic flash flooding. Some areas of the County, including Fort Lauderdale, saw a month’s worth of rain in one hour, leading to widespread economic losses and a federal major disaster declaration. Though this storm was a 1-in-a-1000-year rainfall event, it is one example of the very real threat of climate change in this densely developed, densely populated county.
Hazen worked in partnership with Broward County’s Resilient Environment Department to assess the risk and evaluate solutions.
Guillermo Regalado, has decades of experience as a team leader and project director for water resources projects in Florida, Puerto Rico, and South America.
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Top Image: A major rainfall event in spring 2023 confirmed model predictions of flooding impacts.
Grounded in robust data, innovative strategies, and community input, the Resilience Plan provides a clear and actionable roadmap for the next 50 years.
Water, Water Everywhere
Increased rainfall intensity is only one facet of the County’s flood risk. With 23 miles of Atlantic coastline and a complex drainage system dependent on multiple agencies, Broward County faces threats from sea-level rise, rises in the groundwater table, and higher storm surges and tides. Intense heat is also becoming the norm, disproportionately affecting the County’s most vulnerable residents and workers.
The Hazen team developed detailed hydrologic and hydraulic models to study the interplay of these conditions, aligning the model used by the South Florida Water Management District (SFWMD) flood protection level of service (FPLOS) program with localized hydrology. Hazen modeled the future conditions for multiple storms with 2- and 3.3-foot sea-level rise scenarios. The model incorporated a 23% change factor in each potential rainfall event. Based on these results, the team identified critical infrastructure at risk of flooding. The team then created a GIS-based Scenario Viewer to visualize this dataset and communicate the risks.
These models inform the Plan’s recommendations for adaptation strategies, including expanded surface water storage, green infrastructure, increased seawall height, infrastructure hardening and relocation, and redevelopment. This suite of strategies will ultimately serve as the foundation for the County and its municipalities to invest in the necessary adaptations to prepare for climate change impacts predicted over the next half century.
The Scenario Viewer: This digital tool, which is publicly accessible, captures and displays the results of extensive flood modeling. Users can select various combinations of sea level rise, rainfall, and storm surge scenarios to view associated future flood conditions by location.
Adaptation Strategies
While flooding is often experienced as a local phenomenon, Broward County’s complex interconnected drainage and conveyance system must be managed as a whole to protect properties at the neighborhood scale. As experts in interjurisdictional water resources modeling and planning, Hazen was able to apply a system-level approach to evaluate water management strategies across diverse basins and communities.
These strategies include water storage throughout the County, long-term increases to current seawall heights, and green infrastructure improvements that also help mitigate heat. Combinations of adaptation strategies were evaluated using the hydrologic model to understand where these strategies would be most effective and what their cumulative advantages would be, including economic impacts.
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Miles of Enhanced Seawalls
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Control Structures
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New Pump Stations
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Upgraded Crossings
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Acres-ft of Storage
Summary of modeled adaptation strategies: Combinations of adaptation strategies—including storage, green infrastructure, conveyance, and barriers—were evaluated using the hydrologic model to maximize benefits and ROI.
The adaptation strategies can be viewed through a Power Bi application which allows sorting by municipality, subbasin, water control district, and more. This allows for a wide range of prioritization based on needs.
Calculating the Costs and Benefits
Economic analysis plays a core role in the Resilient Broward planning effort, covering direct and indirect impacts of flood risk and adaptation investments. Hazen conducted economic analyses based on several possible future conditions and found that, without significant action, the amount of vulnerable residents affected by substantial flood damage could increase 41% by the year 2050. The model also revealed that, without adaptation, average flood damage to property in Broward County could top $5 billion annually by 2070.
Ultimately, the devastating effects of rising urban temperatures and increased flooding are felt most acutely by vulnerable populations. By layering multiple adaptation strategies like expanded green spaces and green infrastructure, the County aims to mitigate urban heat in Broward’s most at-risk areas.
The Resilient Broward team ensured that the proposed investments are communicated alongside the calculated value of community benefits.
This table from the Resilience Plan's economic feasibility analysis shows adaptation investments are estimated to deliver $31 billion in preserved residential property value, $3.6 billion in average annual avoided damages, and $20 billion in preserved flood insurance coverage, with an 83% reduction in damages county-wide.
The benefits are displayed on the website through the Benefits Dashboard. The tool enables searching economic benefit (e.g. increase in residential real estate value) by census tract and sea level rise scenario. The tool also highlights vulnerable census tracts for ease of viewing and prioritizing.
The Resilient Broward website includes an interactive Scenario Viewer with 360-degree photos with flood renderings to create an immersive visualization of potential flood impacts.
Communication is Key
From its onset, the success of the Plan has depended on direct engagement with a wide range of voices and perspectives. The County hosted an initial resilience roundtable with the local municipalities and water control districts to explain the project and request data for development of the model.
Additionally, the County held listening sessions with representative stakeholder groups and community partners to learn more about the impacts of flooding and heat on people, their property, and their work. By incorporating the community’s insights and concerns at this early phase, the plan’s recommended risk mitigation strategies are more likely to provide appropriate improvements.
To support inclusive stakeholder engagement, Hazen designed project branding, a website, a visualization platform, and an interactive project tracking tool. The online platform includes a scenario viewer and 360-degree street views, providing visual representations of flood impacts.
An Actionable Roadmap for the Next 50 Years
Resilience planning has become a top priority for coastal communities in the face of the effects of climate change. Broward County officials have recognized their vulnerability at the front line of climate change and are taking bold action to adapt their public spaces, infrastructure, and built environment.
Supported by Hazen’s technical expertise, the County has developed a Resilience Plan that is ambitious in scale, complexity, and vision, and one of the first of its kind in the nation. Because it is grounded in scientific modeling, detailed economic analysis, and overall benefit value estimates, the Plan ensures that Broward County’s people and places can follow a long-term road map to “recover, adapt, and thrive” in the future.
