Potomac - 3. Great Falls (MD Lines)

Potomac, Maryland, US


3. Great Falls (MD Lines)

Usual Difficulty V+ (varies with level)
Length 0.5 Miles
Avg. Gradient 100 fpm
Max Gradient 300 fpm

2007 Great Falls Race

2007 Great Falls Race
Photo of Geoff Calhoun by Rick McNamara taken 07/14/07 @ 2.76

Gauge Information

Name Range Difficulty Updated Level
usgs-01646500 2.00 - 3.40 ft V+ 00h52m 7.16 ft (too high)

River Description

Great Falls of the Potomac River is a major set of rapids located about 15 miles upstream of Washington, DC. The main Falls lines drop fifty feet in one-tenth of a mile, creating a Class V+ set of waterfalls. In addition, a portion of the river flows around Olmstead Island in a channel called the Fish Ladder (additional channels flow at higher water).  

The Maryland Lines are the highest volume channel of great falls. These 3 drops are generally run only at low water, and there is no easy line. 


Paddlers have known about Great Falls as long as there has been whitewater kayaking. Many of the features -- such as the Spout, the Fingers, the Fish Ladder -- have names that predate paddling, in some cases by hundreds of years. But it was not until paddlers started running waterfalls regularly in the 1970s that paddlers began to seriously consider running the Falls. The first descent of Great Falls was made in 1975 by local experts Tom McEwan and Wick Walker, with the second descent by Steve McConaughy and Great Falls National Park Ranger Bill Kirby.
Access to the river is restricted on both the Maryland and Virginia sides.

Maryland Side - Paddlers may put in anywhere on the Maryland shore, but may not leave the boardwalk across Olmstead Island. To run the Falls from the Maryland side, most people put in above and run the aqueduct dam, or put in below the dam at higher levels.

Virginia Side - Paddlers may not put in upstream of the Falls. To run the Falls from the Virginia side you must put in at Fisherman's Eddy and then ferry and carry above both O-Deck rapid and the Falls themselves.

Carry up the Flake for multiple laps. If the rocks are wet, this can be sketchier than running the Falls.
Running Great Falls is currently unrestricted. However, to maintain good relations with the National Park Service paddlers voluntarily restrict their runs to less populated times in the park—early morning, late evening, or weekdays—and limit group size and time spent in the rapid.
The Park Service is concerned about running the Falls at popular times because it can draw spectators down off the observation decks and closer to the river's edge -- where they might fall in the water and drown. And, if paddlers spend a lot of time running around and relaxing in the Falls, it can give the impression that such activities are not very difficult or dangerous. Since 1975, at least 30 people have drowned in Great Falls, so the Park Service is understandably nervous about this.
For more information, see the Guidelines for Running Great Falls as written by the Canoe Cruisers Association in 1999. Today regular Falls runners continue to dialog with the Park Service to make sure access remains open to all.
River Signals and Helicopters
The Park Service patrols the Potomac with a helicopter most summer weekends. In an effort to minimize confusion, the helicopter pilots are trained to recognize three signals from paddlers.
  • Everything OK - Tap the top of your helmet with one hand.
  • Emergency - Wave both arms together over your head (like jumping jacks), holding brightly colored objects if possible.
  • Need Medical Attention - Form an X with arms or paddles.
Don't signal the helicopters unless you need them! And if being inspected, be sure to give the OK sign if you don't need assistance. Sometimes hikers call in "emergencies" that aren't actually emergencies.

StreamTeam Status: Not Verified
Last Updated: 2016-10-03 09:45:14


Stream team editor

Rapid Summary

Mile Rapid Name Class Features (Legend)
0.5Pummel5.0Waterfall Photo
0.5Pencil Sharpener5.0Photo
0.5Charlie's Hole5.2Hazard Photo
0.6Horseshoe5.1Portage Hazard Waterfall Photo

Rapid Descriptions

Pummel (Class 5.0, Mile 0.5)


Photo of Geoff Calhoun by Scott Anderson taken 12/02/12 @ a good level

Also known as Sunburst.  The line is level-dependent. Here are my general rules of thumb based on the Little Falls gage:

LF > 2.80 - Build up some speed and launch off the end of the diving board. This is quite possibly the sickest boof known to mankind. Miss the boof and learn how Pummel got its name.

2.60 < LF < 2.80 - The boof kicker turns into a rock, so run right side instead.

LF < 2.60 - The right side dries up at drought levels, forcing you to run the Notch on the left, which is one of the sweetest lines out here. 

there are also other smaller chutes to the left of the notch that have been run at higher levels. 

Below Pummel you have three options (from left to right): Pencil Sharpener, Z-Turn, and Charlie's Hole.

Pencil Sharpener (Class 5.0, Mile 0.5)

Pencil Sharpener

Pencil Sharpener
Photo of Jason Beakes by Ryan Moore taken 07/14/07 @ 2.76

Enter the narrow slot against the river left shore, boof 2-3' onto a boil, and slide down a broken shelf. You must anticipate the cross current or it will push you into the inhospitable crack on the left. Pencil Sharpener is the preferred option when LF < 2.80.

Charlie's Hole (Class 5.2, Mile 0.5)

Charlie's Hole

Charlie's Hole
Photo of Mark Andes by Rick McNamara

A 10-foot sluice into a super-powerful hole surrounded by underwater sieves. It’s named after Charlie Crowley, who escaped by crawling out along the bottom (bursting both eardrums in the process). This line used to be run regularly by boofing left into the eddy, but after numerous close calls and one fatality almost nobody runs it anymore. There is very little margin for error.

Z-Turn (Class 5.0, Mile 0.5)


Photo of Brett Mayer by Scott Anderson taken 12/02/12 @ a good level

Start left of center, then cut hard left down a twisting drop next to a huge midstream rock. Be careful not to get washed around the right side of this rock into Charlie's Hole.  Choose a conservative line. Z-Turn is the preferred option when LF > 2.80.

Horseshoe (Class 5.1, Mile 0.6)


Photo of Sean Devine by Scott Anderson taken 12/02/12 @ a good level

The scariest hole on the Potomac other than Charlie's, Horseshoe has been the site of many near-drownings. The line is level-dependent. Here are my general rules of thumb:

LF > 2.90 - Left line. Boof onto a rocky runout.

2.60 < LF < 2.90 - Far Right (standard) line. slide down the entrance, dont spin out, and boof off the shelf that extends past the hole. You can approach this directly or by doing a hairy ferry on the SOS wave at very low levels.

LF < 2.60 - Center line. super low water only.  Boof off the knuckle through the hole.

If you get stuck in Horseshoe the odds of surfing your way out are slim, so save some energy for the swim.

User Comments

Users can submit comments.
August 13 2008 (3814 days ago)
Mark AndesDetails
The rocks that make up the Flake and MD side carry up get extremely hot. Even when the day time
high is bearable being out on the rocks here adds a whole new element keeping in mind that the
water temperatures can reach 90 degrees. When going out there bring water and be very wary of the
dangers of overheating and it's ability to affect your performance.

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