When heavy rain hits South Florida, stormwater finds its way into Miami-Dade's sanitary sewer system, straining the capacity of lift stations and wastewater treatment plants and increasing the risk of sewer overflows which pose direct threats to public health. University of Miami engineers are helping county officials pinpoint problem areas, prioritize repairs and improve wastewater system performance.
Through a partnership with the Miami-Dade County, funded by a $1 million grant from the Florida Department of Environmental Protection, researchers at the University of Miami College of Engineering are serving as the technical leads on a countywide effort that also includes the Miami-Dade Department of Environmental Resources Management and the Miami-Dade Water and Sewer Department.
"When it rains, a good portion of the runoff from the rainfall ends up in the sanitary sewers where it's not supposed to be and it dramatically increases the flows in the sewer pipes," said David Chin, professor of civil and environmental engineering. "When it exceeds the capacity, it generates what we call sanitary sewer overflows. It also overloads the plant and compromises the effectiveness of wastewater treatment."
Researchers are focusing on two major sources of unwanted water entering the sewer system: infiltrating groundwater that seeps through cracks and imperfections in the sewerage infrastructure and stormwater that flows into the system during heavy rain events. Both increase the volume and flowrates of sewage that must be transported and treated, placing additional strain on the system.
Currently, the project team is overseeing the installation and monitoring of 70 flow meters throughout Miami-Dade County. Combined with approximately 250 existing county monitoring locations, the network will create one of the region's most comprehensive wastewater flow datasets.
"The measurements will come to the University in a dashboard-type format and so we're essentially directly, in real time, monitoring the flows in the sewers," Chin said.
While Miami-Dade County maintains the monitoring network, University researchers are developing analytical tools to help officials determine where unwanted stormwater and groundwater are entering the system and which infrastructure improvements could have the greatest impact.
By helping county officials better understand where these problems occur, University researchers are confident that the project will improve environmental resilience across Miami-Dade County.
The project also provides hands-on research opportunities for two doctoral students, Oscar Vasquez and Kangyu Wang, environmental engineering Ph.D. candidates in Chin's group, who will support field deployments and data collection while incorporating the work into their dissertation research.
The monitoring network is expected to remain in operation through at least 2028, creating one of the region's most extensive wastewater flow datasets.
"We hope the tools and methods developed at the University through this project will help guide future decision-making, regulations and infrastructure planning efforts across the county," Chin said.
