Why has Bethel created a rain garden? Because our goal is to collect the water run-off that our building and hard surfaces displace due to a depression in the land our property is built on, and our rain garden is specially designed to do this. It allows the storm water and snow melt to enter the ground water and water table instead of the storm water systems, streams, rivers and lakes. Part of an environmentally responsible mission includes being responsible with our land and utilizing nature to do things in a natural way.
Let's learn more about rain gardens
There are a wide variety of ways to build rain gardens. Some are in yards, others are in boulevards next to the street. Some have a deep basin to catch water and may even have trenches, tubes, and hoses that bring in extra water from farther away places. Others may simply rely on gravity and the natural flow of water so it will eventually end up in the rain garden. But what they all typically have in common are a few of the following key elements.
Perennial plants are plants that naturally survive our winters and come back on their own year after year. These plants are an important part of the rain garden for a few reasons. They root far deeper than lawn and will help use some of the water that is captured. Their root systems also form a sort of net that holds the rain garden together and helps to catch impurities. Between the soil and these plants, the water is naturally filtered as it soaks deeper into the earth before entering the water table deep underground. Another benefit these plants provide is forage ground for pollinators and a habitat for small animals such as birds. Bees and butterflies as well as many other insects need to gather food (forage). They get their food from flowers in the form of pollen and nectar. By planting more flowering plants in these rain gardens, Bethel is helping to create an inviting and essential habitat for these insects, and the flowering plants have a more hospitable habitat because of the water that is captured, enabling them to be more self-sufficient.
Located where water is concentrated
The most obvious place to create a rain garden is where water naturally gathers or flows. That might be a low spot, or it might be at the place where downspouts are located at the foot of a building. Some rain gardens, like Bethel's, are dug even deeper and have an elaborate base below them that can handle large amounts of water in a short amount of time. They may fill up for a period like a pond, and slowly empty down as that water is soaked up. It is even possible to incorporate water basins as part of a rain garden system. These basins are actual containers that can hold onto some of that water.
A purposeful design
As we have touched on already, rain gardens are designed and installed to be both beautiful and purposeful. In the case of Bethel's rain gardens, we wanted to create these as part of our mission, but in creating these rain gardens, we are also offsetting some of the water that the city of Minneapolis and the Three Rivers Park District encourage us to manage. By doing so, we reduced the fees that the city and county charge us for managing storm water. So you can say Bethel's rain gardens truly deliver on a purposeful design by saving money and being an environmental improvement.
As you enjoy our rain garden, take a look at the different wildflowers, ornamental grasses, and native plants. There is a lot of diversity here--designed to tolerate both wet conditions and dryer conditions when rain is scarce. If you are interested in learning more about rain gardens, check out these resources: metroblooms.org and bluethumb.org.