Lake St. Catherine is a brackish-water lake that is located in eastern Orleans Parish, within the city limits of New Orleans, between Lake Pontchartrain and Lake Borgne in Louisiana.
Between Lake St. Catherine and Lake Borgne was the original Town of Lake Catherine. Established between Unknown Pass and Miller's Ditch, it was settled for railroad workers, trappers, hunters and fishermen.
Wikipedia https://en.wikipedia.org/wiki/Lake_St._Catherine_(Louisiana)
Coordinates 30°7'35.241" N -89°43'52.809" E