Historic modifications to St. Lucie River, most notably digging of the Okeechobee Waterway (C-44 Navigational Canal), connections with the C-24 and C-23 drainage canals, and the associated water control structures, have had impacted water quality throughout the river basin. Intermittent freshwater discharges from Lake Okeechobee have negatively affected the river itself and the connected Indian River Lagoon. The impact takes several forms.
Alterations to St. Lucie River in the past, particularly the creation of the Okeechobee Waterway (C-44 Navigational Canal) and connections with C-24 and C-23 canals, have had a negative effect on water quality throughout the river basin. The intermittent freshwater discharges from Lake Okeechobee have also harmed both the river itself and the connected Indian River Lagoon.