MIAMI-DADE COUNTY, Fla. – Miami-Dade County broke ground Thursday on a multiyear program they say will provide sanitary sewer service to thousands of residents with septic tank systems.

The county says that approximately 120,000 septic tank systems are still in use in Miami-Dade and that 9,000 are vulnerable to compromise or failure under current groundwater conditions.

“As sea-level rise increases, this number will grow to approximately 13,500 by 2040,” the county said in a news release. “Compromised and failing septic tank systems can cause public health risks, environmental impacts, and negative impacts on private properties.”

The initial lateral sewer lines will be installed to connect 340 homes on already failing septic tanks that are spewing human waste into the groundwater and bay.

It won’t come cheap. On average it will cost $7,500 for residents, a fee they will have to cover, but the county has funding to help them connect.