Rain gardens or bioretention spaces are a good and inexpensive way of alleviating flooding issues caused by run-off or heavy down pours.
“Bioretention is a process in which contaminants and sedimentation are removed from storm water runoff. Storm water is collected into the treatment area which consists of a grass buffer strip, sand bed, ponding area, organic layer or mulch layer, planting soil, and plants (Wikipedia definition).”
Rain gardens are more complex than a regular garden or an area with plantings. They involve the layering of different materials below the surface with the careful selection of plantings on the top. The center is depressed to move water into the ponding area. There are many designs and many can be viewed online.
These gardens can be built on abandoned spots or small areas where there is a need to redirect pooling from run-off . Storm drains on the surface often get clogged or backed up during heavy downpours causing water to accumulate on roadways.
Rain gardens are aesthetic as well as efficient. They stop fertilizers and other pollutants from entering our waterways.
There are other low impact “green” ways of dealing with storm water such as green roofs, detention ponds, swales and bioswales, permeable pavements, infiltration galleries and rainwater harvesting.