Pimmit Run,

1. Old Dominion Drive to above Glebe Road

Usual Difficulty	II-III (may vary with level)
Length	4 Miles
Avg. Gradient	45 fpm
Max Gradient	125 fpm

Gauge Information

Name	Range	Difficulty	Updated	Level
FOURMILE RUN AT ALEXANDRIA, VA
usgs-01652500	200 - 5000 cfs	II-III	00h51m	14 cfs (rc= -0.0 )

River Description

The trip starts off with just intermittent class II- rapids for the first third of a mile, but the gradient then increasess to 80 feet/mile, and there are several class III- rapids over the next third of a mile, as the creek twists through Pimmit Bend Park. It next flattens out for about a mile and a half of mainly riffles, until the gradient picks up again to 60 ft/mile a quarter mile before Ranleigh Road. Scout the dangerous passage under Ranleigh Road beforehand. The creek divides into 5 culverts; some may be blocked and others may be too high or too low (depending on the water level). Just below comes Kirby Road, where there is adequate clearance, and then enters the largest tributary, Little Pimmit Run. The gradient eases up again a quarter mile below Kirby Road, as the creek swings alongside the George Washington Memorial Parkway.
But then, a half mile later, as the creek passes a stone wall beneath a small playground on the right (reachable from Richmond St., off Glebe Road), it begins its final mile-long plunge to the Potomac. The gradient increases first to 100 feet/mile, passing beneath the Parkway, and then to 125 feet/mile in the final approach to Chain Bridge/Glebe Road, in a continuous class III rapid with only micro eddies. Scout this section beforehand from the bridge. In lieu of proper eddies, the usual technique is to run aground on the rocks on river right and carry out to the parking area.
For an urban stream, Pimmit Run is rather pretty and clean, and the water, while a deep muddy brown whenever there is enough of it, has only the faintest whiff of sewage, and has the best water quality of any stream in Arlington County. No doubt, its location in the upscale community of McLean is of great help, as is the fact that it flows mostly through parkland (Pimmit Bend, Potomac Hills and Fort Marcy Parks), and only a few houses will be visible from your boat. There are plans to extend the hiking trail to go all the way along the creek. Other than the speed with which the water level drops, its main drawback is strainers. We encountered about 10 that required exiting our boats, but fortunately none were dangerous or required difficult portages.

A few expert paddlers have run the short and dangerous class 5.1 plunge to the Potomac River, which should be scouted carefully on both river right and river left. There is a low-water bridge under Glebe Road (the remains of a gristmill), and most of the flow goes into a 4-foot wide culvert on river left, that is often blocked by tree trunks. Then the creek turns left, and drops some 25 feet over a series of irregular 3-10 foot ledges, with lots of serious dangers. The higher the Potomac is, the more of this rapid that is covered.

Ed Evangelidi testifies:<br>
Be sure to be out of the water well above Glebe Road, as the man-made hazards below can easily ruin your day. Most of the run is scoutable from a marked hiking trail.