Erosion along the East Branch of the DuPage River has caused this tree to fall into the waterway. (c) The Morton Arboretum 2015. All rights reserved.
A healthier river and protection for trees
The East Branch of the DuPage River flows through the heart of The Morton Arboretum. To improve the environmental health and biodiversity of the river and to safeguard important tree collections, the Arboretum and the U.S. Army Corps of Engineers are at work on a river restoration project. The project runs through 2020, although the most visible work was done between 2015 and 2017.
The project will:
- Stabilize the river banks
- Protect the Arboretum’s important tree collections
- Improve water quality
- Replace non-native turf grass with native grasses, sedges, and wildflowers
- Create better habitat for birds, fish, and other wildlife
- Remove invasive species of trees, shrubs, and other plants
- Improve opportunities for birdwatching and other recreation
Reshaping the river banks
The work is taking place along more than 1.5 miles of river in the Arboretum. It involves re-grading the artificially steep, badly eroded banks to give them a gentle slope. Invasive plants that choked the old river banks have been removed, and the new sloping banks are being planted with a variety of native trees, grasses, wildflowers, and other plants.
A healthier ecosystem
The sloped banks and new plantings have created a more natural river’s edge that is home to a greater variety of birds, butterflies, and other wildlife. In the river itself, boulders and other features break up the water’s flow, creating eddies in the water and nooks and crannies where fish, crayfish, and other animals can live and breed.
In addition to improving the river ecosystem, the project will safeguard the Arboretum’s globally important tree collections from further erosion. Over the past several decades, water rushing down the artificially straightened river has scoured the soil from around tree roots, causing some trees to fall into the river and endangering many more. The newly created habitat areas will be a buffer to protect the Arboretum’s Living Collections from erosion by river waters.
Invasive trees have been removed from along the river banks and about 850 new trees and shrubs are being added, along with thousands of other plants, including grasses, wildflowers, sedges, and water plants. We also have transplanted a number of smaller trees elsewhere in the Arboretum. We are propagating new trees and other plants that are valuable to our collections from cuttings. Once they are large enough, we will plant them elsewhere in our collections.
The first phase of the project, in 2015 and 2016, took place on the Arboreum's West Side along the stretch of river between Illinois Route 53 and Interstate Highway 88. It involved tree removal, re-grading, adding features to the river bed, and replanting. In 2017, similar work was undertaken farther north, on a stretch of river that flows through the Arboretum along the east side of Route 53 south of the Hidden Lake Forest Preserve. It is expected to be finished by early 2018.
Until the project's completion in 2020, Arboretum staff and contractors will monitor the river and its floodplain as the plants grow and a greater diversity of plant and animal species develops in the water and along the banks.
The cost of this project is approximately $5 million, with the majority funded by the U.S. Army Corps of Engineers.
Watch this page for project updates. Learn about the planting phase of our river restoration project.
Frequently Asked Questions
Get answers to frequently asked river restoration questions. Learn more