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When it’s summer in the city, and the back of your neck is feelin’ dirty and gritty, nothing hits the spot like a cool dip in the swimming pool. If one’s not handy, you can always chill out under a fountain, fire hydrant, or sprinkler.

None of these substitutes satisfied David Krupsaw. Tired of sweating life on the banks of the Potomac, sometime in the ’30s or ’40s, he installed a massive, reinforced concrete dam across Donaldson Run and created a deluxe hole for the swimming pleasure of his family. Krupsaw, Arlington history buffs may remember, served as chair of the county board during the ’50s. His term was cut short when he was killed in a 1959 plane crash in Jamaica. But Krupsaw left behind a substantial private memorial in the portion of the Potomac tributary that runs through Potomac Overlook Regional Park.

As Martin Ogel, the park’s chief naturalist, walks down a trail to the barricade, he explains that the creek Krupsaw obstructed is so named because in 1842, Robert Donaldson bought 98 acres surrounding the creek from the heirs of George Mason III. Donaldson named the plot “Fairview Farm,” and he and his progeny tilled the land for wheat, oats, corn, potatoes, tomatoes, lettuce, onions, and rhubarb, which they took by wagon and boat to market in Georgetown.

In the woods upstream from the dam, Ogel points to a tree. Carved on the trunk are the words “Edna Donaldson, December 25, 1900.” Edna and her husband, Warren Horstman, lived beside Donaldson Run until the whole parcel was bought by the Northern Virginia Regional Park Authority in 1971. But much of Fairview Farm had been previously sold off to other owners—including David Krupsaw, who built a cabin on the hill overlooking the dam.

Ogel clambers around the dam and approaches an attached concrete chamber that served as a changing room for Krupsaw’s family and guests. “See,” says Ogel, peering into the dank sanctum, now decorated by graffiti, a pillow case, and a few beer cans, “you can see the nails where they hung their clothes.” Ogel spots a bird nesting in the corner above the one-time clothes rack. “I wonder if it knows we’re here.” It doesn’t. It’s dead.

He leaves the avian tomb to inspect the dam itself. “The swimming hole was on the upstream side, you can still see where there was a little beach,” Ogel points out. A winch attached to a gate at the base regulated the stream’s flow; during storms, water slopped over a small spillway on top.

So how did Krupsaw transport the tons of concrete and steel he needed to build the dam into the woods? The nearest paved road, after all, was a mile away, and even sluicing materials down the hill, as Ogel postulates, would have taken an effort worthy of prehistoric sun worshipers.

“He didn’t go out and do it by himself,” laughs Thomas W. Richards, who became the county board chair shortly after Krupsaw’s death. “The stream valley has changed remarkably over the years, the hill wasn’t nearly so precipitous. There are old farm roads all over the place; one reached the base, not too far from the dam.” A truck might not have been able to navigate the dirt roads, but a horse and wagon could have, says Richards.

“Arlington was almost a summer community” for Washingtonians during the first half of the century, says Richards. “A lot of people built cabins. Families would settle in for the summer, and the husbands could commute into the city by train.” One celebrity who vacationed near Krupsaw’s dam was Polish- born silent film star Pola Negri, who rented the cabin that now houses the Gulf Branch Nature Center. When Richards headed the county’s park department, the building was slated for destruction. To save it, Richards pumped the myth that Negri had planted rhododendrons around the house to lure lady-killer and leading man Rudolph Valentino to her love den.


“I don’t know. They were supposed to attract him. That was the myth,” Richards says.

Valentino died mysteriously in 1926 (women of the time blamed a vengeful mistress), and so regardless of whether he was lured to Arlington by Negri’s plants, he never had the chance to swim in Krupsaw’s pool.

The dam, too, succumbed to a vengeful mistress. It was “blown out by Hurricane Agnes” in 1972, says Richards. A wall of water undermined the base, and cracked and tipped the structure so that it lists toward the Potomac. Sand and silt have filled in the old swimming hole. Water flows around the concrete. The chamber now serves as a trysting spot, and only dogs swim in the small pool that has formed below the dam.

Next Week’s Mystery: XXX