Saltwater has intruded into the Biscayne aquifer in Miami-Dade County due to drainage and droughts, affecting drinking water for residents. A study from 2008-2011 used various methods to map the extent of saltwater intrusion. Results show that by 2011, around 1,200 square kilometers of the aquifer were affected by saltwater, with some areas showing increased intrusion compared to 1995. Monitoring also revealed saltwater influxes in canals, impacting nearby wells.