Spanish River Park takes its name from the shallow fresh water stream, which once flowed along what is now the western edge of the park. 

Since its channelization by the core of engineers, the river has become known to boaters as part of  the intercoastal waterway. Early maps show the river as "Boca Raton's Lagoon", But late settlers and developers apparently borrowed a page from history and renamed it the old Spanish river , Remnants of the meandering stream bed are still visible in the park.