Above Lock 21, the canal bed is going quiet. The National Park Service's most recent conditions update, dated October 14, 2026, lists the stretch from Lock 21 to Lock 23 as de-watered. From Lock 17 up through Lock 20 to Lock 21, the canal is still holding water. Walk north from Great Falls Tavern and the water ends partway along, at the lock beside the one parking lot on this stretch that is currently fenced off.
This November, most of the changes along the towpath come from scheduled maintenance. Two separate programs overlap this season. One is the park's yearly preparation for winter. The other is a repair contract for damage from a summer storm more than seven years ago. Between them, they close the Swains Lock lot, leave the canal empty above Lock 21, and send more of the walking toward the tavern lot.
Where the water stops this fall
The Park Service drains the canal every fall to protect the stone masonry from freeze damage. The current conditions page notes that the C&O Canal Company did the same during the canal's working years, and that water usually comes back in early spring. The draining happens in stages, so for a few weeks parts of the Potomac stretch hold water while the stretch next to them is down to mud and stone.
As of the October 14 update, the lower canal looked like this:
| Stretch | Status as of Oct. 14, 2026 |
|---|---|
| Locks 3 to 6, Georgetown to Lock 6 | De-watered |
| Widewater | Watered |
| Locks 17 to 21, the Great Falls Tavern reach | Watered |
| Locks 21 to 23, Swains Lock to Pennyfield and Rileys Lock | De-watered |
The Park Service says water levels can change without warning, and the remaining watered sections are scheduled to drain before winter. By the time this is read, the water in the Great Falls reach may be lower than the table shows. The canal boat rides at Great Falls are already closed for the season, and so is the Georgetown boat downstream.
Swains Lock is closed because of a 2019 storm
The Swains Lock parking area at milepost 16.7 has been closed since October 13. The Park Service says the closure will last "several weeks" and has not given a reopening date. The reason goes back to July 8, 2019. That day, heavy rain caused a flash flood that eroded the embankments along the Great Falls Entrance Road and damaged the timber retaining wall around the Swains Lock lot.
The NPS project page for the flood repairs lists the damage the contract has to fix: eroded embankments that threaten to undermine the entrance road, and road shoulders scoured badly enough to leave major drop-offs at the pavement edge. At Swains, crews will remove the timber wall and replace it with an embankment of fill and seeded topsoil. Along the entrance road, the work includes dry-laid stone "rockery" walls, rebuilt shoulders, a new drainage pipe and stabilized stream beds. The money comes from the Emergency Relief for Federally Owned Roads program, through an agreement between the Park Service and the Federal Highway Administration's Eastern Federal Lands office. The work is scheduled in phases from 2025 through 2026, depending on weather.
The entrance road, which is MacArthur Boulevard, stays open throughout. Single lanes close from time to time with flaggers directing traffic, so getting in and out of the Great Falls area can be slow on a working day. The project also explains why the road surface still feels rough. This contract covers the roadbed underneath, which keeps the road in place. The worn pavement gets only temporary patches for now. A full pavement rehabilitation is still being designed and is scheduled for a later date. The rough road will outlast this repair contract.
Where a walk can start instead
With Swains closed, the Park Service points walkers to the next lot upstream, Pennyfield Lock at milepost 19.6, and the next lot downstream, Great Falls at milepost 14.3. Canal Quarters at Lockhouse 21 stays accessible during construction. The detour has its own maintenance, though. Each nearby access point has some work going on this fall:
- Pennyfield Lock, milepost 19.6. DC Water is repairing a critical section of the Potomac Interceptor sewer near Lock 22, and the Park Service warns of delays on Pennyfield Lock Road. This is also the drained stretch, so a walk from here runs beside an empty canal.
- Great Falls Tavern area, milepost 14.3. The lot, restrooms, Great Falls Overlook, Olmsted Island boardwalk, Gold Mine Loop and River Trail are all listed as open. In the Gold Mine Tract, the land between MacArthur Boulevard and Berma Road, park rules keep visitors on the designated trails.
- Billy Goat Trail, milepost 13.8. Sections A, B and C are all open. Section A usually closes when the Little Falls river gauge reaches 5 feet and reopens when it drops to 4.8 feet. The Park Service can close it at lower readings, and the Billy Goat Trail page suggests calling the tavern visitor center at 301-739-4200 to check.
- Carderock, milepost 10.5. The Carderock tunnel has had an alternating one-lane closure since July 27. Parking Lot 1 has reduced capacity because a contractor is staging there, and the restrooms are closed for emergency repairs, with portable toilets in their place.
For now, the tavern lot is the easiest base: it has open restrooms, water still in the canal and every trail in the area open. It is also the lot more of the area's visitors will be using while Swains is closed.
A shorter week at the tavern, and faucets off in mid-November
The Great Falls Tavern Visitor Center at 11710 MacArthur Boulevard is open 9 a.m. to 4 p.m. on Sunday and Wednesday through Saturday. It is closed Monday and Tuesday, and it is closed on Thanksgiving Day, November 26. On a Monday or Tuesday walk, the towpath and overlook are available but the building and its staff are not.
Drinking water is the other seasonal change. The Park Service usually turns off the faucets at camping areas across the park around mid-November so the pipes can dry out before a freeze. The campsites stay open, but visitors need to bring their own water. The faucet list shows the Swains hiker-biker faucet already off, while the Great Falls Tavern restrooms and the Swains Lockhouse still have potable water. The Park Service notes that park buildings run on municipal water, so the winter shutoff mainly affects the campground faucets. On a longer walk, the tavern is a reliable place to refill.
What comes after the repairs
The Swains Lock lot is expected to reopen within weeks. The Park Service is also planning for the longer term. The 2026 Great Falls (MD) Development Concept Plan covers the land from the Anglers parking area north to Swains Lock, between MacArthur Boulevard and the Potomac. That is the same ground this fall's repairs cover. Its stated topics are visitor experience, resource management, safety, and parking and traffic. Part of the land is owned jointly by the Park Service and The Nature Conservancy. The Virginia side of the falls is managed separately by George Washington Memorial Parkway and is not part of the plan.
The flood repair page shows how heavily this area is used. The Park Service counts more than a million visitors a year at Great Falls, Maryland, and calls the entrance road and Swains Lock primary access points to some of the busiest parts of the park. A parking change at either spot affects the whole network of trails, which is the reason the planning process lists parking and traffic among its main topics.
After the towpath
The usual stops after a walk have changed this year as well. At Cabin John Village on Seven Locks Road, Store Reporter reported that Pura Vida Miami would open on February 12 in the former Colada Shop space, with the patio it shares with Sisters Thai being redesigned. Carmen's Italian Ice opened in June, as reported by Store Reporter. The MoCo Show gave its address as Suite 113. In late August, The MoCo Show reported that Colony Grill had closed permanently at the same center after its lease was not renewed.
Closer to the village, Maurizio's is being built at 10120 River Road in the former Renato's space. Eater DC included it in its fall 2026 preview, and The MoCo Show reported in September that it was expected to open this fall. As of late October, the restaurant's website still says "coming soon."
Two dates fall in the same weeks as the faucet shutoff. The Community of Cabin John calendar lists its Turkey Trot for Thanksgiving morning, November 26, at 10 a.m. on the field behind CBNRC, also called Cabin John Local Park. A vendor registration page advertises a Small Business Saturday Holiday Market at Cabin John Village on November 28, from 11 a.m. to 4 p.m. Cabin John Village's own site is the place to confirm it before going.
For many Potomac homeowners, the canal is part of daily life, and access to it depends on the work described here. If you are thinking about a home near MacArthur Boulevard or River Road and want to talk through how the park, its access points and its upcoming plans fit into that decision, Michael Rankin is glad to speak with you. Book an Appointment.
