City of Hallandale Beach Sustainability and Vulnerability Planning

RS&H has been assisting the City of Hallandale Beach with comprehensive sustainability and resiliency planning since 2017. RS&H developed a Sustainability Action Plan for the city in 2017 and helped establish 14 short- and 14 long-term goals in six focus areas. To achieve these goals, 27 projects and 30 additional best management practices were adopted. The project portfolio is projected to generate a $2.2 million net benefit to the city with a ROI of 52% over a 10-year period.

The plan included a recommendation to conduct a climate change vulnerability and adaptation plan. RS&H is providing vulnerability and adaptation planning, including flood hazard mapping, flood exposure assessment, ground water assessment, future precipitation analysis, shoreline change analysis, and initial strategy development in support of this plan.

RS&H has assessed a range of flood conditions, including tidal flooding, storm surge, and FEMA flood zones (including 100-year and 500-year) for a baseline condition and three additional sea-level rise scenarios based on the current Southeast Florida Regional Climate Compact Unified Sea Level Rise Projection.

Using the Steps to Resilience (StR) framework and FernLeaf’s software product (AccelAdapt), the assessment considers both vulnerability (which includes exposure) and risk to certain assets, including the city’s public facilities, critical infrastructure, access to those facilities, and infrastructure. Potential economic impact analysis focuses on changes in annual sales volume and jobs/employment associated with commercial properties vulnerable to flooding under the flood scenarios.

RS&H also reviewed data and studies related to changes in future heavy precipitation and existing stormwater design/management guidance. Using best available data, potential changes to the future peak 24-hour rainfall for recurrence intervals for future time periods was estimated qualitatively and compared to design/management guidance currently in use by peer local governments, with implications for stormwater design/management at Hallandale Beach identified.

RS&H reviewed local hydrogeology studies to provide discussion on aquifer vulnerability to sea level rise, anticipated changes in the water table, and saltwater intrusion, including anticipated community impacts of changes in groundwater hydrology induced by sea level rise and a changing climate (i.e. rainfall, recharge/discharge).

RS&H reviewed historical shoreline change data to qualitatively estimate changes in recession rates due to sea level rise, including how sea level rise may increase shoreline recession rates, with assessment of potential impacts to recreation and beach nourishment programs.

RS&H identified adaptation strategies based on noted vulnerabilities within the city and relevant to city infrastructure. Strategies consist of combination of policy, regulations, ordinances, as well as flood mitigation actions including protection, relocation, elevation or hardening of existing infrastructure, such as shelters, water-wastewater infrastructure, public safety facilities, etc. RS&H worked with the city to collaboratively review and prioritized identified strategies. Gross estimates of priority project costs were developed, accompanied by a discussion of potential benefits. Benefits will be quantified if feasible. Projects were organized into a preliminary work plan, accompanied by policy recommendations.