This is a concept that has recently become popular.

As construction of building and roads continue to take place, and storm water continues to get impacted, rain gardens are going to become critical to the survival of many creeks and streams, and even our lakes. When you have an impervious (meaning a solid, non water penetrating surface) surface, it will heat up in the sun light, and when water hits it, the water heats up, collects together and rushes off the surface into the drainage ditch that leads through a stream to the rivers and lakes. First thing is the extremely high temperature damages wildlife, and second, the concentration of the fast flowing water damages the natural flow of the stream. We will go into more depth on this at a later time, today I want to explain how a rain garden helps to much of this problem. In our Paver vs. Concrete blog, we touched on a solution to the impervious surface problem.

A Rain Garden in my own words is a big hole in the ground that drains water back naturally into the soil, filled up with organic dirt and planted with native plants that will survive the weather and tolerate the extreme conditions. A rain garden is put in a location where a concentration of water is exiting from a building or parking lot and is designed to catch all the water and hold it for up to 48 hours. The rain garden is designed like a bowl, and sometimes has a drain pipe at the very bottom for extreme water exit. The bowl is planted with all kinds of native wildflowers, shrubs and trees and is mulched usually with hardwood mulch. The plants are what helps the water percolate through the soil and back into the underground streams. As the hot water exits the parking lot, it collects in the basin of the rain garden. All the anti-freeze and oils from the vehicles is in this water that collects in the rain garden. As the water percolates through the plants and the soil, it is cooled off and cleaned. The oils get stuck in the mulch and on the plants. The plants will rejuvenate their leaves and the mulch will either compost itself, or is removed and replaced every so often. All this together, protects our streams from pollution and replenishes our underground water.

Rain Gardens can be installed in many different ways. There can be a stack system, where you have multiple basins for heavy rain events. You can use the underground drainage for extra water control.

Rain Gardens can also be applied to many different applications. I have personally installed rain gardens in home owner’s yards in places where the concentration of water from the driveway and neighbors yard was eroding their grass away. We put in this beautiful garden that doubled as water control and solved the problem.
If you have any questions and comments, please ask. A short blog cannot extensively cover this whole topic. Go to this link for residential image of a rain garden. Notice the beauty of it. Go to this link for a layout of the design.

Happy Streams