What is a Level?

The answer really depends on who you are talking to!

During the recent C&O Canal Association annual meeting, the NPS provided an excellent summary of projects planned or in progress on the park.  The NPS references park project sites by the level they are located on.

After the presentation, some level walkers commented to me that it was a great presentation, but the park had the wrong levels for the project locations.  My response – the park is 100% correct, and so are the level walkers. There are two kinds of levels! One is used by level walker volunteers and the other is used by the NPS.

Level Walkers in the canal era were employees who monitored a canal level and ensured that there were no problems that inhibited operation of the canal – including leaks and blockages. Level Walkers in the C&O Canal Association program are volunteers who monitor the level they are assigned to. They monitor the conditions of the towpath and structures, pick up trash, remove light tree debris and report any issues.

The C&O Canal Association Level Walker program was originally founded in 1960. For a bit of history about the program visit https://candocanal.org/atp/1960-03.pdf and view the predecessor of our Along the Towpath quarterly publication.

The initial number of levels in the Association program was 69 and they really haven’t changed. I’ve heard that factors determining the level alignments and numbers may have included the number of volunteers, the canal access points that existed at the time, and of parts of the canal that were not traversable. We’ll call these the “Association levels.”

With the 69 Association levels, the average length is 2.67 miles per level – but it doesn’t work out that evenly. Levels lengths range from Level 28, at 1.20 miles, to Level 53, at 5.66 miles. Quite a variation but, as noted, access was and is the key factor. Level walkers appear to be happy with their level assignments. If they do have a long level, they sometimes find ways to do the level in two parts.

In canal and historical terminology, a level is the section of canal between two locks. Visualizing a canal as a stairway, the locks are the risers and the levels are the treads.  When the NPS refers to a level it identifies it by the lock on the downstream end. As an example, Level 37 is the section of towpath above Lock 37.  Call these the “NPS levels.”  There are 75 of them.

This became an interesting bit of research, and I made a table to visualize the differences.  The NPS levels and Association levels are quite different. The NPS levels have an average length of 2.46 miles. They range in length from a mere 4/100ths of a mile on Level 1, to the 13.72 lockless miles of Level 50. 

I consulted with the NPS and they provided some clarifications. The level above Tidelock is called Level 0. The inlet locks at the dams don’t factor in, so the lower lift lock defines the level number – i.e., Level 44 continues to Lock 45, even though it passes Dam 5.  Also, the two “fractional” locks below the Paw Paw Tunnel aren’t used as level numbers – Lock 63 1/3 is the lower end of Level 63; Lock 64 2/3 starts Level 64, and Lock 66 starts Level 65; all the levels numbers above that are offset from the lock number by 1.

Scrolling down the list, the comparisons are interesting. Five levels are exactly the same, although with different numbers, like Association Level 54 and NPS Level 59; both are between Locks 59 and 60. Some long levels in one numbering system span numerous short levels in the other system.  The Association and NPS numbers only agree on one very short place – the 4/100 mile section between Mile 0.38 and 0.42 is Level 1 in both systems.

The differing level numbers can also present potential communications issues. A level walker might see a downed tree near Dargan Bend (around Mile 65) and tell the NPS “There is a tree blocking the towpath on Level 25.”  Level 25 to the NPS would mean Edwards Ferry/Lock 25 (around Mile 31).  So, we should always use mile markers or landmarks for reference to avoid confusion.

Next time you talk about levels, just remember who you are talking to!

Main Image – The towpath near Antietam, which is part of Level 27 to the Association or Level 37 to the NPS

The Catoctin Aqueduct at Mile 51.53 is the lower end of Association Level 20, or just inside of NPS Level 29
While Lock 20 at Mile 14.30 is the lower boundary of NPS Level 20, which is the lower end of Association Level 7.

Upcoming Park Events

Hello Level Walkers!

The following notifications are from the C&O Canal NHP related to upcoming park virtual events.

Thanks, as always, for your support of the park!



March VIP Speaker Series: Overview of the Canal For All Program
Thursday, March 31, 2022 12:00 PM-1:00 PM.

Nanette Nyce will share some of the personal stories of Canal For All with C&O Canal NHP Volunteers as well as seek your insights into helping this wonderful program continue to grow. The Trust’s Canal For All program provides opportunities for education, stewardship, and volunteerism that are safe, welcoming, and inclusive for all.

To foster diversity and to better reflect our community, the program engages BIPOC, differently-abled, LGBTQIA+, and other underrepresented or disadvantaged communities. The Trust partners with community organizations to diminish barriers to participation and to create exciting and relevant opportunities to Play, Learn, Serve, and Work in the C&O Canal National Historical Park. 

Join on your computer or mobile app
Click here to join the meeting


Dear Volunteers, 

In 2022, we are holding quarterly all-volunteer calls to provide you with information and updates about the park. The meetings will be recorded and shared with you afterwards so that if you cannot make the scheduled time, you will still be able to get the info. 

Our 2nd quarterly call is scheduled for Wednesday, April 13 from 10-11:15am and will be held on Microsoft Teams. There is a phone call-in option if you cannot join via computer, however, please note that there will be a slideshow presentation so we encourage you to join via Teams if possible. 

During the April call Andrew Landsman, Natural Resource Program Manager, will be presenting on some of the current natural resources projects taking place in the park. Shelley Albee, Interpretive Ranger, will also highlight some of the recent and ongoing Digital Media projects. Please try to get into the meeting 5-10 minutes early to allow for any troubleshooting or issues. 

Join on your computer or mobile app

Click here to join the meeting

Or call in (audio only)

+1 202-640-1187,,524952792#   United States, Washington DC Phone Conference ID: 524 952 792#


C&O Canal NHP Status – 12 March 2022

Hello Level Walkers,

Weather is on the way and the NPS issued the following notification.

Thanks, Steve

Dear Volunteers, 

With the wintry weather forecast, the volunteer program is suspended on Saturday, March 12. The park will be open to the public, but volunteers are not authorized to work in the park. This is to ensure your safety during the inclement weather event. 

If you choose to visit the park on Saturday, you must do so as a private citizen. For updates on any park closures please check the park website or the park Facebook page.  If you have any questions, please contact your park staff program coordinator. 

Thank you and stay safe! 

Christiana Hanson

Chief of Interpretation, Education, and Volunteers