What is rainscaping?
Rainscaping refers to the process of enhancing a landscape or property to better manage the stormwater draining off that area. Rainscaping seeks to interrupt the "urban water cycle" before the stormwater flows into the storm drain. Traditionally we have sought to pipe away stormwater as quickly as possible to the nearest river or stream, a process that degrades ecosystems, lowers property values, and raises taxes. In a phrase, rainscaping can be thought of as managing rain water where it lands.
Why is rainscaping important?
The below pictures of Plaster Creek were taken less than 24 hours apart. They illustrate the rapid change in water level that occurs after a rain event called a stormwater surge. Stormwater surges on Plaster Creek are unnatural events that exist because of the way we deal with stormwater—we pipe it directly to our streams and waterways as quickly and efficiently as possible. These surges can create dangerous flash floods, but it's not just the change in water level we're concerned about. Higher levels of E. coli bacteria, sediment (see how brown the water is in the picture on the right), nutrients from fertilizer, industrial metals, and other pollutants wash into the creek.
Examples of rainscaping
Rain gardens
The classic rain garden is designed to be an endpoint for stormwater that runs off a property or off of some type of impervious surface (a surface that water can't drain through, eg. a parking lot, a rooftop, or, to a certain extent, a lawn). Planted with native plants that don't require added nutrients or pesticides, a rain garden captures stormwater and allows it to percolate through soil layers and into the water table in a slower, healthier, and more natural way. This percolation process filters out sediment and other pollutants that would otherwise flow into our local waterways, and it reduces harmful flash floods that can be common to urban waterways.
For a more technical overview of rain gardens, complete with calculations, procedures, and site analyses, check out the Michigan Low Impact Development guide's chapter on rain gardens.
Interested in creating a rainscape? Check out how to build your own rain garden.
Bio-swales
Bio-swales are similar to rain gardens in that they are vegetated depressions for capturing stormwater and allowing it to percolate into the ground, but bio-swales are designed (often by engineers) for heavy-duty stormwater management. They are bigger than rain gardens and often less formally planted and manicured.
This bioswale was seeded and planted with native prairie grasses and wildflowers and captures the stormwater from a 2 acre parking lot on Calvin University’s campus. The prairie is now mature enough to have prescribed burns every few years to manage weedy species and encourage the native plant growth. The water must travel through the large s-curve and rise above a standing pipe before it can spill over into a wetland, something that rarely happens. This project is a great example of how native habitat restoration can be used in responsible stormwater management.
Buffers
Vegetated buffers are an important practice for farmers or anyone who owns land on the creek or any of its tributaries. Keeping on Filling the banks of the creek and its tributaries, no matter how small, with trees, shrubs, grasses, and/or wildflowers benefits the water quality in several ways:
- Erosion control: Plant roots form extensive networks in the soil, helping hold it in place and keeping banks from eroding and washing into the creek.
- Shade: Trees and shrubs provide shade to the creek and its tributaries. This cools the water, improving natural habitats.
- Filter: Plants intercept runoff, helping filter out nutrients and trapping sediment. In an agricultural setting, they help filter runoff that can contain animal manure and E. coli bacteria, preventing health risks downstream.
Rain barrels
More and more homeowners are capturing stormwater from their roof by attaching their gutters and downspouts to rain barrels. The typical rain barrel holds 55 gallons of water, and it can fill up with just a half inch of rain! Rain barrels can be used to water vegetable or flower gardens, or they can be used together with a rain garden to catch the first 55 gallons of stormwater, which can later be used to water the rain garden during hotter, drier times.
Trees
Trees are an excellent solution to stormwater issues no matter where they are in the watershed. Leaves and branches provide lots of surface area to intercept rainwater, slow-releasing it as droplets are shed to the ground. Trees take up several gallons of water per day, as well as excess nutrients that would otherwise pollute the watershed.
Fall leaves
Mulch, compost, or collect your leaves, but don't leave them in the streets. Check out our Leaf-let for more information about fall clean-up.
Everyone can do something
There are several simple, smaller steps we can all take to improve water quality in Plaster Creek, the Grand River, and Lake Michigan. These include moving pet waste to a trash can, reducing the amount of lawn fertilizer you use, or washing your car on the lawn or gravel instead of the driveway.
For more information about Rainscaping and the Grand River, check out LGROW (Lower Grand River Organization of Watersheds) for many great resources.