Underwood Creek Flood Control and Habitat Restoration
2019 Engineering Excellence Award | Best of State
Entering Firm: Inter-Fluve
Client: Milwaukee Metropolitan Sewerage District
Category: Water Resources
In the 1960s and 1970s, Underwood Creek was substantially altered from its natural state. The meandering river was diverted into a concrete ditch for flood management but this solution created its own problems. 50 years later those problems meant that a change was necessary.
Inter-Fluve identified the problems created by the concrete diversion ditch. First, it eliminated fish habitats through inadequate depth, wide variation in water flow speeds and additional barriers built into the ditch. It was a danger to people during rainstorms and was also an eyesore. It actually caused more flooding upstream because of new developments; this counteracted the reasons the ditch was constructed in the first place.
The design team decided to remove the concrete channel and associated structures. In its place, a natural-looking riffle-pool channel was constructed. The riffle-pool design utilizes rocks and differing water depths to slow down the water during storms. The new channel also varies in width and fits better with the natural environment resulting in water velocities well below the targeted maximum. This creates a safer environment and still controls flooding by disbursing the water’s force. A huge benefit of the new channel is that is has restored the marine ecosystem from the original creek. Large boulders in the new channel create quiet pockets of water for migrating fish and the ecosystem that supports them. This environmental sustainability was a big win for the client and the team. The new design also cuts down on maintenance costs that were required of the old concrete channel.
Awards judge Matt Spiel said, “The Underwood Creek project is a great example of how thoughtful planning and engineering can benefit the human and natural landscape. Despite challenging constraints, the project team developed a solution that improved flood control, while restoring the stream to a natural-looking and functioning stream that provides several environmental benefits.”
The new Underwood Creek points to the ability of engineering to achieve ecological friendly solutions without sacrificing functionality. A more holistic view of engineering created a design that achieves multiple objectives.
