Catching up on natural changes and coming changes on the unnatural Southeast Side

We met at the Ford Calumet Environmental Center at Big Marsh Park, which opened in 2021. The last time I visited it was in early construction, and I wondered whether people would come out to it.

Well, on a Tuesday, the joint was jumping with bicyclists and people working on computers and visiting inside the nature center. Luis Cabrales, the program and event facilitator for the Chicago Park District, accurately called it a ‘‘hub for nature’’ for the nearby community.

‘‘Ford workers come for lunch here,’’ he said.

Our group started at Square Marsh, a project with multiple partners (The Nature Conservancy in Illinois and the Illinois International Port District). Square Marsh, abutting the north end of Lake Calumet, probably won’t be accessible to the public for years, but much progress has been made, especially on invasive buckthorn, phragmites, purple loosestrife and reed-canary grass.

‘‘We’re especially excited about the installation of the new water-control structure this summer — a critical milestone that sets the stage for future restoration efforts and long-term ecological health,’’ emailed John Legge, the director of climate adaptation and sustainability for TNC/Illinois. ‘‘Another encouraging development is the progress we’ve made in controlling invasive plant species, which has significantly improved visibility and access to Square Marsh.’’

A great blue heron flew over. Red-winged blackbirds trilled.

Just a couple of years ago, you couldn’t see squat from the road. Now, you can see in and envision what is coming.

Botts was bubbling about the potential from the water-control system.

‘‘Ecologically speaking, it’s a complete makeover,’’ Botts said. ‘‘It will return to a hemi-marsh with the new water structure.’’

Someone identified a Caspian tern passing. Common gulls, either ring-billed or herring, flew.

Square Marsh is now virtually all common carp. Eventually, Botts said, the marsh will be drained and the carp eradicated. Because of the carp, there is no aquatic vegetation.

Once the carp are eliminated (hopefully by the fall of 2026), fresh soil will be brought in — possibilities for inexpensive clean soil exist — and appropriate vegetation will be planted. The final step will be the introduction of native predator fish to control any remaining carp by eating the young. The water-structure link with Lake Calumet will allow in predator fish such as smallmouth and largemouth bass. Other species also might be introduced.

A belted kingfisher jerk-swooped past. Dark cormorants flew.

The completion of Square Marsh is years in the future, but it has the potential to provide a significant connecting bike path with a bridge over the neckdown on Lake Calumet.

‘‘We are not here to just restore the fish, birds and amphibians; it’s here for the people,’’ Botts said.

We moved on to Indian Ridge, which was used for slag dumping for decades.

‘‘Despite that, it maintained ecological value,’’ Botts said.

Canada geese lifted and settled in the distance.

Even in its degraded phase, the area was well-known to birders.

When cleanup in the area began in 2015-16, crews simply worked on removing trash, tires and a couple of cars.

‘‘I was just happy they didn’t find a body,’’ Botts said.

Since I last visited Indian Ridge a couple of years ago, the park district has done great work on trails and the oak savanna. It’s becoming a destination for locals and others.

On our way back, egrets stalked a distant shoreline and a pair of non-native mute swans fed near the road.