Zoning & Building Safety:

Zoning and Building Safety Department
Stormwater Management

Rain Gardens

A rain garden is a popular technique of building a garden bed in a low area that accumulates water after a storm. It is planted with native plants that help to collect and filter rain water and allow it to seep naturally into the ground. By installing a rain garden on your property, you can greatly increase your contribution to preserving clean rainwater, creating natural, native habitats, preventing local flooding and reducing water pollution.

What is a Rain Garden?
Unlike specific points of pollution, such as some factory discharge pipes, nonpoint source pollution comes from many different spots. From farmlands to suburban lawns, people use the land in ways that cause nonpoint source pollution. And it is also more difficult to control nonpoint sources of pollution.

Why a Rain Garden?
A rain garden is a natural way for you to help solve our stormwater pollution problems, help recharge groundwater, and protect our water resources. A rain garden keeps rain on your property, where it naturally belongs. By creating a rain garden, you can help improve water quality in local streams, rivers, and lakes. You can use rain the way nature intended, instead of throwing this resource away. In addition, rain gardens are attractive landscaping features. They use native species of plants that are adapted to our region, and can be low maintenance while providing habitat for native wildlife and butterflies.

Back to top


What Makes a Rain Garden a Rain Garden?
A rain garden resembles a regular perennial garden in many ways. It is designed with deep-rooted plants that come back year after year; it is pretty to look at; it often has lovely flowers, grasses, trees and shrubs.

So what makes it different from any other perennial garden?
There are certain qualities that make a rain garden unique.

  • The garden bed is prepared or sometimes replaced to a depth of two feet in order to de-compact the soils and make the garden able to absorb water.

Benefits of Rain Gardens

  • Rain gardens are lovely landscaping features.

Back to top


There are many good resources on the internet and even at local nurseries and home improvement centers. If you download this document PDF Document there are step by step instructions on how and where build a rain garden to what type of plants to consider

  1. Water flows in from slope, paved area, or pipe
  2. Wide, shallow basin with flat, level bottom and gently sloped sides
  3. 12 to 24 inches of fast-draining soil
  4. 2 inches of mulch
  5. 6 inches of ponding depth
  6. Berm or stones to stem or slow down overflow
  7. Perennial plants


rain barrel

Water is getting scarce in some areas, and water prices are rising. Many communities are rationing water. Droughts are causing much distress. A lot of your yards may be parching this year.

Well, here is some good news! There is a free resource you may not have thought of using to water your garden and lawn--RAIN. Consider some low-tech, old-fashioned technology for keeping your plants green and happy: rain barrels.

Does anybody remember rain barrels? The nice soft water is perfect to water your gardens. Rain barrels are making a comeback, because they can save you money-and sometimes save your garden! The added advantage is that by using rain barrels, you can also help solve our stormwater pollution problems.

Have you ever wondered how much water runs off your roof? During a typical moderate storm of 1" of rain during a 24 hour period, over 700 gallons of water will run off the average roof, an impervious area of about 1,200 square feet. In one rainy day, your roof runoff could fill up fourteen bathtubs! Add up the many roofs in your city and we're talking a lot of water.

Stormwater from your roof is usually directed away from your yard and on down the street or road. On its way, it picks up pollutants; dirt, lawn clippings, pet waste, salt, lawn chemicals, gas and oil, and you name it (are you grossed out yet?). This water and the pollution load it carries generally goes to the nearest storm sewer, and from there to the nearest stream or river. Studies have determined that up to 70% of our surface water pollution is washed in there by stormwater. You can help solve this problem by keeping stormwater on your property and using it the way nature intended; to water the plants in your yard. A double benefit!

You can make a rain barrel, or buy one. Buying a ready-made rain barrel can be expensive. You can buy them from catalogs and on the internet (just do a search for "rain barrels"). Some garden centers carry them; call yours and check. Ready-made rain barrels range from about $70 to over $175, and shipping costs are additional. If you do buy a ready-made one, consider these safety features:

  1. Your barrel must be made of "food quality" materials, so the water you save will remain uncontaminated.
  2. Your rain barrel should NOT have a lid that easily comes off. This will insure that little creatures and little people will not be at risk of drowning in your rain barrel.
  3. Your barrel should be safely screened so it doesn't turn into a mosquito condo.

Just think: landscape watering consumes about 40% of your total water bill! Now think of how much money you will save with rain barrels…while you are protecting your local rivers, streams and lakes. Wouldn't it be great if everybody got a rain barrel? Be the first in your neighborhood.


Do your homework. Check with local nurseries or home centers or use internet resources. Many websites have planting tips and provide lists of available plants that are suitable for various soil types and microclimate conditions of rain gardens. Try our links section for some useful websites.

Back to top

Rock Island County Office Building (map ExternalLink.gif)
