The threat of inland flooding in South Florida is increasing due to high groundwater levels and the need to protect fresh water from salt water intrusion. High groundwater in South Florida is a major contributor to flooding inland, especially during extreme rainfall from storms or the rainy season.
A recent study led by a recognized hydrologist at the Department of Earth and Environment, Florida International University, found that the flood management practice of raising the ground water levels in South Florida to prevent an increase in salt water intrusion leads to higher canal waters and subsequently increased inland flooding. The study, “Economic Impacts of Urban Flooding in South Florida”, found that current flood water tables don’t take existing ground water levels into account when mapping out flood management plans. The study was published in December 2017 in the scientific journal Science of the Total Environment. The study was funded by a grant awarded to the university by the National Science Foundation (NSF).
Water resource management experts protect South Florida’s fresh drinking water from salt water intrusion by keeping ground water above a certain level. The problem discovered by the Florida International University researchers is that, as the sea level rises, ground water may need to be increased as well, raising the water level and causing inland flooding.
Rising sea levels, along with higher rainfall and ground water can collectively cause significant flooding. Many of the current flood water tables do not plan accordingly for the permeability of the ground in South Florida. There is a misperception that the land in South Florida is impermeable but, in fact, the ground is quite permeable, and the ground water level is close to the surface, the study found. New flood water diagrams provide water resource managers with a new model they can use to address the flooding problem. Rising sea levels will result in extensive inland flooding in the future.
Historically, ground water levels and flood insurance claims have provided data to help water managers quantify the trade-offs that must be made between the economic costs of flooding and the human consumption need for fresh water, especially in urban areas such as Miami-Dade County. Data collected over the last 40 years indicates that ground water levels are rising consistently with increasing sea water levels. This could lead to double or triple the number of severe floods in the area by 2060. The purpose of the study was to help water resource managers and urban planners have access to a better understanding of flooding and the economic impacts of continuing to raise ground water levels to control salt water intrusion.
Lanier Upshaw, Inc. specializes in helping Florida homeowners and businesses assess their risk for flooding and other damage. Our trained experts will help you explore your risks and select the right policy for you. To learn more about how Lanier Upshaw, Inc. can help you cover your risks, contact us here.