Rockingham Bottoms opened to the public Thursday.
The property includes a multi-use trail that connects Nahant Marsh to the Mississippi River Trail, surrounded by over 300 native trees, like oaks, pecans, and hickories.
Brian Ritter, Nahant's executive director, says the extra land will help some of its current residents.
"We have found a federally endangered bumblebee called the rusty patch bumblebee, they need this kind of habitat to be able to thrive."
"We also have a couple other federally endangered species found on site, a couple of bats, as well as at least 30 state threatened or endangered species that are found here at the reserve," he said. "This just gives them more of a chance of surviving."
Five years ago, Nahant Marsh bought the 39 acres, doubled its wetlands, and planted a prairie buffer.
"We removed almost 500 tires, an ice cream truck, a boat, you name it, hundreds of bags of trash that we literally pulled out of the wetlands," he said. "That was kind of our first step in the restoration."
"We took it even further, we decided that we wanted more wetlands here, the more wetlands we have, the more flood water we can take on from the river, the more impact we can have on wildlife, and cleaning up the water as it leaves the property."
Rockingham Bottoms is named after an early Euro-American settlement that was on the land. Ritter says staff found artifacts from that time, including Native American ones.
Nahant plans to add signs, a picnic area, and geocaches.