Scott's Run Reopened for Fall. The Next Closure Is Already on Fairfax County's Calendar.

Is Scott's Run open again? As of late August, yes. Fairfax County's Department of Public Works and Environmental Services finished the sewer work on August 10 and the park authority closed out its own maintenance and reopened the gates on August 21, just as the oaks and beech along the outer loop start turning. That timing matters less than what got the park to this point. This is the third time in three years that Scott's Run has shut down because of the same piece of buried infrastructure, and the county has already penciled in a fourth closure for next fall.

If you've hiked here before and found the lot chained off more than once since 2024, you weren't imagining a pattern. There is one, and it runs straight through the middle of the park's most popular trail.

The Same Pipe, Three Times

Scott's Run sits on top of three county-owned siphon pipes that carry wastewater from McLean under the Potomac River, through Carderock National Park in Maryland, and into DC Water's Potomac Interceptor. When those pipes have problems, the park closes, because the access road into the facility runs along the same trail everyone hikes to reach the waterfall.

Here's the closure history as the county and local reporting have laid it out:

Three closures, three different official reasons, one shared cause. The first two were emergency responses to a facility that inspectors described as failing. The 2026 closure was the planned fix for that failure, using a trenchless lining method called cured-in-place pipe, which the county chose specifically because it disturbs less ground and fewer tree roots than digging up the line.

Phase 2 is already on the books. It covers the segment of the same siphon that runs under the river into Carderock, and the county's own project page lists construction beginning in fall 2027, with the design phase and final construction limits still being worked out. That gives Scott's Run roughly a full year of open trails before this same story plays out again.

What Actually Reopened

The trail network itself didn't change shape. The outer loop is still the same 3.3-mile route that most hikers use: the Potomac Heritage Trail north from the main lot, a crossing of Scott's Run itself over stepping stones, the short climb to the waterfall, then east along the river on the rockier, root-heavy stretch before connecting to the Oak Trail and looping back past the Stubblefield Falls Overlook Trail to the smaller parking lot.

What's worth knowing is what the county spent six months protecting. The park authority has been explicit that the closure wasn't just about pipe access. Officials noted the shutdown also kept visitors from wandering off-trail around the perimeter fencing into a stream valley that's part of the Potomac Gorge, one of the rarer plant and animal habitats in the mid-Atlantic. Trailing arbutus, Virginia bluebells, and sessile trillium grow on the steep hillsides here, alongside a stand of hemlocks old enough that the county's own description calls them descendants of trees that arrived during the last ice age.

None of that changes what you'll see on a fall hike, but it explains why the county treats a plumbing project like a conservation project.

The Detail Fairfax County Puts Right on the Park Page

The most interesting sentence about Scott's Run isn't in a hiking blog. It's on the county's own park listing, describing the creek that carves the whole gorge: "Perhaps the greatest dichotomy is Scott's Run, the main creek that runs through the site." The dichotomy is this. The stream that produces the waterfall everyone photographs starts a few miles upstream, directly below the parking lots of Tysons Corner Center, one of the highest points in Fairfax County. From there it runs east through business parks and condo complexes along the Beltway before it ever reaches the forest. By the time it drops over the falls, the water has picked up enough runoff that wading and swimming are banned, with signage at the base of the falls warning of a fine for anyone who ignores it.

It's a small fact that changes how you look at the water. The prettiest spot on the trail is downstream from a shopping mall parking lot, not upstream from one.

There's an older story tucked into the same ground. A stone chimney on a bluff above the river is the last visible piece of the Burling family's cabin, mostly hidden by tree cover now, a reminder that this was working land before it was a preserve.

Planning a Fall Weekend Here

The trail rules haven't changed with the reopening. Dogs are welcome on leash. There are no picnic shelters, no water fountains, and restrooms are limited to portable toilets at the two parking areas off Georgetown Pike. Both lots are small and free, and they fill by mid-morning on weekends, which makes an early Saturday start or any weekday visit the more reliable option if you want to actually park.

Scott's Run also isn't an island. It sits close enough to Great Falls Park and Riverbend Park that a fall outing can easily cover more than one stop, especially if the goal is river views without repeating the same half mile of trail twice. For anyone weighing a move to this stretch of McLean along Georgetown Pike, our McLean neighborhood guide covers how that corridor connects to the rest of town.

The Window You're Actually Working With

Treat this fall and next as the stretch you have. Phase 2 construction is still in design, and Fairfax County has said the final scope and schedule will firm up as that design work continues, but fall 2027 is the target the county has published for the next closure of this same facility. Barring another emergency blockage in the meantime, that gives Scott's Run roughly a full year of uninterrupted access, which is longer than the park has managed at any point since early 2024.

That's not a guarantee. The last two unplanned closures both arrived in February, both tied to the same aging siphon system finally giving out under pressure nobody could fully predict. But for now, the gates are open, the loop is intact, and the leaves are turning right on schedule.

If Scott's Run is part of why you love this corner of McLean, or part of what you're picturing for the next place you call home, Thomas Cauley can help you figure out what's actually within reach along Georgetown Pike this fall.