* Lake Peigneur Drilling Disaster - 50 m (164 ft) drop (all below sea-level) flowed for 3 days in 1980 due to an oil rig drilling into a salt mine* Cunningham Falls – 26 m (78 ft), cascading waterfall* Great Falls (Potomac River) - 16 m (76 ft), cascading waterfall* Kilgore Falls - 5 m (17 ft),free-falling* Muddy Creek Falls – 17 m (53 ft), the highest free falling waterfall in Maryland* Cascade Falls (Ellicott City) - +/- 15 feet, small cascading waterfall in Patapsco Valley State Park* Raven Rock Falls (Parkton) - Little-known cascading waterfall in Gunpowder Falls State Park.
===== Louisiana =====* Lake Peigneur Drilling Disaster - drop (all below sea-level) flowed for 3 days in 1980 due to an oil rig drilling into a salt mine===== Maryland =====* Cunningham Falls – , cascading waterfall* Great Falls (Potomac River) - , cascading waterfall* Kilgore Falls - ,free-falling* Muddy Creek Falls – , the highest free falling waterfall in Maryland* Cascade Falls (Ellicott City) - +/- 15 feet, small cascading waterfall in Patapsco Valley State Park* Raven Rock Falls (Parkton) - Little-known cascading waterfall in Gunpowder Falls State Park.