We all have heard the phrase when it rains, it pours. When that happens it can cause serious flooding and dangerous conditions. Urbanization and development have led to increased incidents of flooding in urban areas. Although not all problems are easy to solve, many of the issues related to storm run off can be mitigated with smart landscaping.
Individual homeowners can make simple changes to improve storm run off and manage rain water on their own property, which also helps the surrounding areas. The more people jump on board, the better it will be overall. Here are a few ways to improve storm run off on your property.
Improve the Soil
Often, poor soil structure, especially heavy clay soils, don’t allow the water to percolate through fast enough, leading to run off and erosion. Aeration allows you to introduce air pockets without destroying structure building aggregates (a common issue with tilling methods). You can then top dress and fill-in those pockets with compost. Compost adds vital organic matter and microbes that help to improve the soil structure. Introducing mycorrhizae, worms, and other fauna and beneficial bacteria also help improve soil structure and nutrient composition and create a more porous environment for water to naturally move through.
Plant Deep Rooted Perennials
Strong and deep root systems also help improve porosity and percolation rates in soils. Replacing shallow rooted turf grasses and annuals with prairie grasses, shrubs, and other deep rooted perennials help create pores in the soil and reduce erosion. Many of our favorite native plants work well for this purpose, so just look for hardy varieties in your region.
Build a Rain Garden
You can leverage the natural flow of water and direct it away from sensitive structures such as a home by designing a rain garden. A rain garden utilizes bioswales and berms to direct and capture water. The base of the rain garden is amended with compost and mulch and filled with deep rotted perennials to help drive the water down into the soil. This is especially ideal for areas on top of aquifer recharge zones as rain gardens help capture and clean water for the aquifers. If the plants will sit in water for awhile, you will need to look for varieties that don’t mind wet conditions. Otherwise, any deep rooted perennial can suffice. Look to your county extension for a complete list of rain garden plants in your area.
The University of Wisconsin Extension Service put together a definitive guide on rain gardens. It explains exactly how to design and build it and gives some recommendations for plants. Its best to refer to your extension agents lists instead though for varieties that best fit your region.
Install Rain Catchment Systems
In addition to smart landscaping, you can install a rain water harvesting system. Small homes can do with just a gutter system and rain barrels. Medium and larger scale properties will want to leverage a larger, slightly more complex harvesting system with tanks and filters. The size of the system is determined by the total amount of rain that can be collected based on the size of your roof. The basic formula is:
Total square footage of your roof x .623 = GPI or the potential number of gallons that can be collected per 1” of rainfall.
For example a 1200 s/f roof can collect roughly 748 gallons per inch of rainfall. So the system would need to be able to capture and hold at least that much and/or have a method for directing any overflow. There are a growing number of service providers who can help you install one or you can DIY it. Below are some links to a few great resources.
Reduce Impervious Cover
Another big change folks can make that will have significant impact is to reduce the amount of impervious cover that exists on the property. This means eliminating surfaces that water can not pass through, such as concrete, pavement, mortared stone, etc. Replace them with either plant material or material such as decomposed granite, river rock, “Dry stacked” stones, or mulch—anything that will allow water to pass through.
The more you can do to direct water into the soil and capture excess, the better. You can make small changes over time, so that they are manageable, focusing on plant options first and graduating to catchment systems as time and budgets allow. The more we can make smart landscaping decisions that work with nature, the less often nature will come back to bite us in the —you get the picture.
If you have any questions feel free to drop a comment or shoot us an email. Always happy to help!