Renata von Tscharner is retiring after 18 years as president of the Charles River Conservancy, which she founded in 2000 with the goal of cleaning up the river and its banks to make the Charles swimmable. The Globe recently spoke with von Tscharner, who was trained as an architect and urban designer in Switzerland, about her tenure and the challenges the conservancy faces moving forward.

This interview has been edited and condensed.

Q: What were some of your proudest moments leading the Charles River Conservancy?

A: The opening of the skate park [in East Cambridge] in fall2016 was extraordinary because land that was contaminated, that was not used by anybody, suddenly was a place where athletes could gather and practice their sport. It created a space that helped people do something healthy and active in the city.

Another thing I’m very proud of — 14 years ago, together with [the performance group] Revels, we started something called River-Sing. It’s a celebration of the autumnal equinox, where thousands of people gather in late September at the Weeks Bridge to sing songs, and then a boat comes down the river . . . it’s an absolutely magical celebration [that] brings out the beauty of the river.

Q: What were the most challenging parts of your job?

A: There are always a lot of challenges when you work with different agencies. We work both with the Department of Conservation and Recreation and also with the Mass DOT on bridges. Whenever you work with different agencies to coordinate all those efforts, it’s a challenge.

Q: Do you swim in the Charles yourself?

A: I certainly do — on those official “City Splash’’ days. I’m also a windsurfer, so sometimes I fall in. It’s a wonderful experience to swim in the Charles and look up at the greenery and up at the State House. We’ve picked a location for a swim park [downriver from the Museum of Science] where there’s no conflict with boats and there’s parkland next to it. It’s a wonderful place to swim.

Q: What kind of challenges does the new executive director, Laura Jasinski, face?

A: We have a new capital project that we’re working on, and that is to create a swim park — we will raise the money to build it, just as we did with the skatepark. The water is swimmable most of the time, but there is no approved location for swimming, so the conservancy has been offering what we call “City Splashes’’ one day a year. So far 1,200 people have participated and many are on the waitlist. So that will be a major effort, where people can swim not just one day a year, but for the [whole] season.

Q: Do you have any plans for retirement?

A: I have a granddaughter in Paris, so I guess I will see her a bit more often! I deeply care about [Boston], about the river, so my main goal is to make sure that the organization is ready for the new leader. I will remain on the advisory board — I will not be in the office after my retirement gala on June 2, but I will definitely be available if Laura can use my help.

Q: What do you see as the future of the Charles?

A: I think that the Charles already is an enormous asset, but it could be so much more than it is today. This is a very densely settled city, so to have this publicly owned land in the middle is an extraordinary chance. The potential of the river is not fully used yet, so that’s what the conservancy will be working on — to make the river and parkland on both sides more accessible and attractive, to have places where people can sit in restaurants along the river. There are many improvements, and we’ve only just started.

Margeaux Sippell can be reached at margeaux.sippell@globe.com. Follow her on Twitter @MargeauxSippell.