Miami Beach isn’t sinking; the water around it is rising. If sea levels rise 2 feet over the next 25 years, 40% to 60% of the Florida city is projected to flood regularly. Yellow dots show locations most at risk.
In 2015, flooding required public works to raise 4,200 feet of asphalt streets. In the future, roads below high-tide levels will have a minimum crown elevation of 3.7 feet when raised, a height that provides an estimated 50-year life and facilitates further elevation if necessary. Estimated to cost $400 million over five years, the city’s also building more than 50 pump stations.
To expand Miami Beach’s existing flood-prevention program, public works plans to build about 20 more stormwater pump stations in addition to 31 built since the program's inception in 2014. The design treats floodwater before discharging to the environmentally sensitive Biscayne Bay.
The city’s nearly 60 new pump stations discharge 15,000 gpm to 80,000 gpm. Flow capacity is calculated using an estimate of tributary area served by stormwater system, sizing of supplemental collection piping, new storage chamber capacity, and operations and maintenance considerations.