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Four men, three in NPS uniforms, standing over a trail under construction.

Left to right, Mason Meyer, Jamie, Callais, Jason Christenson, and David Driapsa on the accessible trail under construction at the comfort station at Ellsworth Rock Garden, Voyagers National Park.

Kevin Ammons: Welcome to the Preservation Technology Podcast, the show that brings you the people and projects that are bringing innovation to preservation. I’m Kevin Ammons with the National Park Service, National Center for Preservation Technology and Training. Today we join Debbie Smith as she speaks with landscape architect, David Driapsa, FASLA, and Jason Christensen, a maintenance worker at Voyageurs National Park. In this podcast, they will talk about increasing visitor accessibility while preserving the character of the historic landscape.

View of raised flower beds and stone sculptures on the granite outcropped hillside

Ellsworth Rock Gardens (David Driapsa, 2010)

Debbie Smith: David and Jason, thank you for joining me today. David, could you tell me a little bit about Ellsworth Rock Gardens?

David Driapsa: Ellsworth Rock Gardens is an historic district in Voyageurs National Park. It was the summer home of Jack and Elsa Ellsworth, and they spent a number of years here, decades, building these beautiful gardens of rock.  They laid up glacier rock on the granite outcroppings and then planted flowers in raised beds. It became known as the showcase of Lake Kabetogama.

Debbie Smith: How long did it take him to build the gardens?

David Driapsa: I’m going by recall, but I’m thinking something like 20 years or some more possibly.

Debbie Smith: Do you know when he started to build them?

David Driapsa: I know that he stopped in about 1966. He worked on these gardens between 1944 and 1966.

Debbie Smith: Why is there a need for this new trail? I know there are a number of trails here already.

Rock sculptures on a section of granite outcropping

Several of Ellsworth’s rock sculptures on the granite outcropping.

David Driapsa: Well, the real need, Debbie, is for a universal accessibility, so people with maneuverability disabilities can access this historic landscape equally as anyone who is mobile.

Debbie Smith: I noticed when I came here there was very steep steps at the current landing.

David Driapsa: Yes, there is and I counted those. There are fifteen risers, which would make it very difficult or impossible for some people to access.

Debbie Smith: I’m interested in this trail because it goes through an historic district. How is the trail going to blend in with that historic landscape?

David Driapsa: Well, that is the beauty of the preservation treatment. It is a solid trail that will be wheelchair accessible, and the top surface is grass just like the surrounding area. So, it does not impair the visual quality of the historic resource.

Debbie Smith: Jason, can you tell me, I’ve seen some of the construction documents and plans that David created. Can you tell me about the layering in the lawn?

Construction drawing showing the layering of the basecoat, geotextile, geogrid, paver cells, sandy loam, and turf.

Path Construction, Ellsworth Rock Garden. (David Driapsa, 2011)

Jason Christensen: Sure. We first we flagged the lawn where the trail is going to go. Next, we dug down 10 inches till we found a good solid soil to work off of, and then we brought in a sandy clay material that we packed in layers. After that, we lay a separation fabric of a geotextile material over the new soil, which is basically the base layer for the trail, the foundation of the trail. And then, over that it’s the geogrid, they look like big cup holders. That’s the final grade, and the grass grows through the geogrid when it’s all said and done, to match the surrounding grass.

Debbie Smith: I can see some grass in the grid coming through, and I understand it was seeded this year. Is that correct?

The plan view site plan depicts the three trails.

Section of the Accessible Path Plan, Ellsworth Rock Gardens (David Driapsa, 2011), with color added to show path through the lawn (purple), comfort station path (yellow) and switchback path from dock (red).

Jason C.: Yes. It was seeded about a month and a half ago.

Debbie Smith: It’s amazing how much grass has already grown through.

Jason Christensen: Yes, it’s coming up real nice.

Debbie Smith: I understand you started in May. When do you hope to complete the project?

Jason Christensen:
Well, also involved in the project are new his-and-hers comfort stations, a big dock with much more dock space, and a switchback  trail for accessibility up the slope. We hope to be done with the accessibility part of the project by this fall (2018), and to complete the project we’re looking at probably mid-summer (2019) to have the dock in and the comfort station built, and everything wrapped up.

Debbie Smith: Jason, I noticed the difference in the trail. Around the location for the comfort station, it’s a crushed gravel. Can you tell me how this construction is different from the trail?

Jason Christensen:
The trail edge is outlined with  5 x 6” green-treated timbers that we fill with a crusher fine, so it’s a real good solid surface.

Debbie Smith: Does it compact down with time?

View of the walkway lined with timbers

Compacted crushed stone walkway at the site of the new comfort station

Jason Christensen: Yes, and we run compactors over it so it’s completely solid and crowned in the middle so it sheds water off of the trail.

Debbie Smith: Is it something that you will have to maintain by continually rolling over, or will it just stay in place?

Jason Christensen: You might be looking at maintenance-free for 10 to 15 years. You might have to occasionally add bit more gravel, but they maintain themselves pretty well.

Debbie Smith:  I understand that at I. W. Stevens historic site within Voyageurs National Park, there’s a similar type of a trail that’s been recently put in. It’s also handicap accessible. David, could you tell me a little about that project? I understand you also designed that site.

David Driapsa: Yes, I.W. Stevens Resort is another visitor day-use historic site, and the main trails are handicap accessible. There are backcountry trails that are not accessible, but the main ones leading from the boat dock all the way over to the picnic area are accessible.  Even the boat dock is accessible, so the visitor gets an overview of how Mr. Stevens lived from his home to his sauna and the lawns and the cabins.

Compacted gravel path lined with timbers passing through mature pine trees

Accessible trail at I.W. Stevens day-use area.

Debbie Smith: These are two examples of where handicap-accessible trails have been constructed at Voyageurs. Do you know if there are more planned?

Jason Christensen: Yes, recently at the Ash River Visitor Center where they constructed a nice handicap-accessible trail, and picnic areas at Rainy Lake City and Camp Marston on Rainy Lake. There are plenty more sites to come.

Debbie Smith: Thank you both for talking with me today.

David Driapsa: It’s a pleasure being here.

Debbie Smith: Thank you. Bye now.

David Driapsa: Bye.

Kevin Ammons: Thank you for listening to today’s show. If you would like more information, check out our podcast show notes at www.ncptt.nps.gov. Until next time, goodbye everybody.

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