Traffic Patterns

All rowers on the Occoquan are expected to follow the traffic pattern designated below.

Be aware that crews from Oxford boathouse may be on the water along with Sandy Run rowers. Always be on the lookout for fishing boats, kayaks, canoes, and paddleboarders. Scullers rowing in groups need not row single file, but they should keep to the proper side of the river.

Basic traffic pattern

The general traffic rule is: proceeding up river, stay to the Fairfax side of the river; proceeding down river, stay to the Prince William side. '

Do not use the “middle third” of the river.

Occoquan Map Traffic Pattern

Launching and returning from Sandy Run

After launching, stay to the Fairfax County side of the blue or orange barrel-sized buoy. Do not cross to the PW side until you’ve cleared the buoy.

Returning to Sandy Run from upstream, remain on the Prince William side until you are downstream of the blue or orange barrel-sized buoy, then cross the river to Sandy Run, keeping the buoy to port.

Traffic Patterns Around Sandy Run Dock

Holding a proper course on the reservoir

Do not try to hold the shortest course from headland to headland. Doing so may put you on the wrong side of the river.

The river shallows along the inside of any turn; be careful of submerged objects.

Proceeding upstream at Jacob’s Rock, pass to the Fairfax County side of the small red buoy where the yellow environmental buoy used to be.

Proceeding upstream from below Fountainhead towards Ryons Dam. (Named after dam builder Fred B. Ryons. Picture of original dam here. May be referred to as Ryan's dam in some places).

Do not cut the turn too closely: stay to the Fairfax side. There are submerged hazards on the PW side of the turn, and rowers coming downstream will give them a wide berth.


Fishing boats, kayaks, canoes, paddleboarders: Always look out for fishing boats, kayaks, canoes and paddleboarders. Do not expect fisherman or paddlers to call out warnings even when collisions are imminent.

Occoquan Dam: Rowing near the Occoquan Dam is prohibited and dangerous. A string of orange buoys prevents boats from approaching too close to the dam.

Ryons Dam: When water levels become low, submerged sections of Ryons Dam (upstream from Fountainhead) on the Fairfax side may become a danger. This hazard is usually marked with a small flag or stick.

Submerged tree trunks: When water levels are low, be mindful of submerged obstacles on the inside of any turn, especially at Fountainhead and Jacob’s Rock.

Floating debris: Debris often becomes a hazard after heavy rain or storms. When debris is heavy, members are discouraged from launching.