Design and Build a Rain Garden

Design and Build a Rain Garden

Essential questions: 
What is green infrastructure and how is it used to manage stormwater?
What is a rain garden and how does it function to manage stormwater?
What are the key steps in siting, designing, and installing a rain garden?

The Design and Build a Rain Garden lesson series leads students through the siting, design, and installation of a rain garden. The activities provide the basis for a rich, interdisciplinary, hands-on learning experience.

Whether or not you are able to install a rain garden, completing parts 1-3 and the final evaluation from Part 4 will provide students with many opportunities for learning, enjoyment, and collaboration.

  • Part 1: Includes background content for students to understand how rain gardens address and fit into larger stormwater management issues and approaches. The lesson lays the foundation for the class to locate, design, and install a rain garden.
  • Part 2: Students work to identify the best site, size, and shape for the garden.
  • Part 3: Students engage in a creative design process to come up with a class design for the rain garden.
  • Part 4: Focuses on the installation of the rain garden and includes the final evaluation.

Rain gardens are one of a group of stormwater management solutions known as green infrastructure. Other green infrastructure projects include rainwater harvesting, bioswales, permeable paving, green roofs, and more. Generally, a rain garden manages water from impervious surfaces such as roofs, sidewalks or paths, driveways or parking areas, or other relatively small, discrete areas.

According to Hans Hesselein, landscape architect, green infrastructure related to stormwater is “when you intentionally manage stormwater in an environment that mimics a more natural system… treating stormwater as a resource rather than a waste product.” More broadly defined in a paper on educational opportunities in green infrastructure, it is “a network of human-managed and natural ecosystems that together enhance ecosystem health and resilience, contribute to biodiversity, and benefit human populations through the maintenance and enhancement of ecosystem services.”

Why manage stormwater at all? Stormwater is a wonderful thing: All life depends on it, it fills our rivers and lakes (and reservoirs!), and it is a core part of the water cycle. At the same time, stormwater can cause flooding and, especially in urban environments, can pick up pollutants as it runs off roads, roofs, and other impermeable surfaces that ultimately get carried into bodies of water.

In a natural environment, stormwater gets absorbed into the ground and the soil, rocks, and plant roots filter the water. A rain garden is designed to mimic this process and absorb stormwater in a given area that might otherwise overflow or run across impermeable surfaces. Rain gardens are also simply that—gardens that beautify our lives and provide us an opportunity to engage with nature.