Gabriel Kaprielian set a homemade island gently into the languid waters of the Schuylkill on a clear, calm evening in May – and it tipped to one side, the brightly painted deck quickly sinking beneath the surface. He didn't panic, though: A quick adjustment, and it was bobbing easily with the tide.

Soon, Kaprielian had launched an entire fleet of the odd little river crafts, each a miniature floating habitat adorned with flashy, laser-cut animal shapes and solar-powered LED lighting strips, and planted with blue-flag iris, soft rush, and fox sedge, species native to the wetlands that once lined the river before the banks were channelized to make way for industry.

"It's creating microhabitats," he said. "They also serve as an advertisement for the native plants and animals. These are intended to drive public awareness of native plants, as well as awareness to the disappearance of tidal ecology along the Schuylkill River."

The project is part of an "ecotopian toolkit" – that is, ideas for coping with, or at least contemplating, a future of shrinking coastlines and warmer waters.

Other demonstrations include a floating charcoal-and-native-plant filter that's meant to serve as the riparian equivalent of a Brita, a series of handmade litmus and water-quality tests, a field guide to plants of the lower Schuylkill, and an interactive river map. These interventions, which are being installed one at a time at Bartram's Garden in Southwest Philadelphia through May and June, are both artworks and speculative proposals for understanding and managing the changing river.

These are the winning entries in An Ecotopian Toolkit, a new (and, perhaps, soon-to-be annual) design competition run by the Penn Program in Environmental Humanities, which itself is somewhat new, having been founded in 2014 as an interdisciplinary response to a looming environmental crisis.

The idea behind that program, said Bethany Wiggin, founding director of the program, is to take environmental studies beyond the realm of earth sciences: "Environmental humanities proposes that in this moment we live in, where humans are impacting the planet in such profound ways, a more integrated approach bringing in the arts and humanities in knowing and understanding the environment and thinking about the challenges we face is not only interesting but also timely and even urgent."

To that end, in 2015, Wiggin connected with environmental artist Mary Mattingly, who had created WetLand, a floating residence, art project, and laboratory, on the Delaware River for the Fringe Festival. After the festival concluded, Wiggin helped arrange to move the project to Bartram's Garden for an continuing residency.

That sparked Wiggin's interest in the lower Schuylkill – but as she undertook more research, she realized there wasn't much data on that stretch of the river beyond the drinking-water catchment.

So, with collaborators from Drexel University and Bartram's Garden, she launched a public research seminar about the river, inviting academics, environmental groups, boating groups, and civic associations to participate.

"We were so interested in this question of 'How do you know a river? How do you illuminate a river, and how do you get people to see it with different eyes?' " she said.

Plans include a sediment study to be done with scientists from the Academy of Natural Sciences, a floating archive of river data, and the development of a curriculum for students in programs at Bartram's Garden or the John Heinz National Wildlife Refuge in Tinicum.

But, she said, "It's getting artists and art-makers on the river that has helped people see it and understand it in quite different ways, and not just zoom by it at a thousand miles an hour on their way to the airport."

On Saturday, Joanne Douglas will distribute homemade litmus tests and chemistry lessons, part of a fiber-art project and water-quality analysis.

And on June 10, artist Carolyn Hesse will install a more abstract project, titled Suspend, a string of rectangular glass panels meant to shimmer on the river surface as they trace a path parallel to the rusting swing bridge above. (She previously tried to install it at high tide on a full-moon evening in May, but just as she set out to unfurl it across the river, five power-skiers appeared, sending up wake and foiling the plan.)

"The Schuylkill is such a funny place to work. You never know exactly what's going to happen," Wiggin said.

Last Saturday, Jacob Rivkin, an artist and a lecturer at Penn Design, and Eric Blasco, a landscaper who focuses on native plants, built their own ecotopian tool and dropped it into the river.  Their Bio Pool is a sort of homemade floating water filter. It's a raft lined with nitrogen-absorbing wetland plants like cattails and duck-potatoes, and contaminant-collecting biochar that Rivkin and Blasco made themselves by slowly burning wood.

"It's something that would definitely need to be scaled up, but it's kind of a speculative artwork that's imagining a need and a solution," Rivkin said.

It's meant to be approachable, but also inspirational.

"You tell someone I'm making a Brita filter on the river, and it gets them excited about the impact they can have on the environment around them."