Green Infrastructure Improvement Project

As our city grows, we are finding smarter, more natural ways to manage rainwater. By using "green infrastructure," we can reduce neighborhood flooding and keep our local waterways clean by mimicking the way nature handles water.

What is Green Infrastructure?

Traditional drainage systems rely on pipes and concrete to move water away as fast as possible. Green infrastructure—like bioretention cells and rain gardens—works differently. It uses engineered soil and native plants to capture, filter, and absorb rain right where it lands.

Green Infrastructure Goals

• Stormwater capacity - Maximize water retention during rain events and slow drainage in the area. Connect to the existing storm sewer.
• Stormwater quality - Utilize natural plants and landscaping to facilitate natural water treatment and improve the quality of water entering the storm sewer.
• Education - Educational signage and hands-on classroom green infrastructure experiences for local schools and the community.
• Space Utilization - Improve the space's utilization and aesthetics for the neighborhood.

Key Benefits to the Community

• Flood Protection: These systems act like a natural sponge, holding large amounts of water during heavy storms to prevent it from overflowing into streets and basements.
• Cleaner Water: As rainwater soaks through plant roots and soil layers, it naturally filters out pollutants like oil, salt, and sediment before they reach our rivers.
• Sustainable Landscapes: By using native South Dakota plants, we create hardy landscapes that thrive in our climate, support local pollinators, and require less water and mowing than traditional grass.

How a Bioretention Cell Works

A bioretention cell is more than just a garden; it is a high-functioning drainage tool composed of several layers:

• The Ponding Area: A shallow depression that temporarily holds water during a rain event.
• Engineered Soil: A specific mix of sand and organic matter that allows water to soak in quickly while trapping impurities.
• Native Plantings: Deep-rooted plants like Butterfly Milkweed and Little Bluestem that create permanent channels for water to reach deep into the ground. 

Educational Spaces

Many of our green infrastructure sites serve as "outdoor classrooms." These areas often feature mowed paths and signage, providing students and residents a hands-on way to learn about the water cycle and environmental stewardship.