Published September 21. 2012 4:00AM
When it rains, it pours - and sometimes it floods or pollutes.
That's the problem with stormwater runoff, a condition that happens when rain falls so fast or heavily that it can't be absorbed by the earth.
Stormwater runoff has become an increasing problem as development creates more hard surfaces like roofs, parking lots and even compacted lawns that interfere with natural drainage, said Sandy Barbic, education specialist with the Summit (Ohio) Soil and Water Conservation District.
Stormwater poses a number of problems, Barbic said. For one thing, it picks up pollutants as it rushes over the ground, carrying them to bodies of water - either directly or through storm sewers.
Runoff can also cause erosion, and the dirt that's collected along the way can cause problems in bodies of water by blocking sunlight and settling on the bottom, raising the base so there's less room for water and more chance of flooding.
Nitrogen and phosphorus in the runoff can promote growth of algae, which use up oxygen when they die and decay, Barbic said. That leaves less oxygen to support aquatic life.
And in areas with combined storm and sanitary sewers, stormwater can overwhelm the sewers and cause overflows and backups into basements.
Here are some of the methods you can use to divert the problem of runoff.RAIN BARRELS
A rain barrel is an old-fashioned idea that's getting new respect. The barrel typically ties into a downspout and collects rainwater coming off a roof, so the water can be reused for purposes such as watering plants and washing cars.
Most rain barrels hold about 50 to 75 gallons, but rain barrels can be linked together to increase capacity.
The water they capture is free of the chlorine and salts used in treating water, and its pH is neutral. That makes the water better for plants, proponents say.
Algae can form if the barrel is made of a white or clear drum that sunlight can penetrate. All barrels need to be removed and stored in winter and the downspout reconnected.RAIN GARDENS
Rain gardens are collections of native plants in slight depressions that are strategically situated to collect runoff. They're designed to hold the water just long enough to let it percolate into the soil, where it's filtered and cleaned naturally.
Native plants are recommended because they require little maintenance and don't normally need fertilizers or pesticides. The plants used in a rain garden must be able to tolerate both temporary wetness and dry periods between rainfalls, and they must have large root systems to help absorb rainwater.
Siting is important. A rain garden needs to be situated down-slope from the house and at least 10 feet from the foundation, so water doesn't leak into the house. PERMEABLE PAVEMENT
Unlike traditional pavement that sheds rainwater in sheets, permeable pavement lets water flow through it and into the ground. It's sometimes used in commercial settings to reduce runoff from large parking lots, but it can also be used to replace residential patios, driveways and walkways.
The term permeable is often used to describe any type of flow-through paving, but used precisely, it's only one kind, said Rich Sherer, paving products manager for the Belden Brick Co. Other types are called porous or pervious, terms that describe how the water gets through the surface.
Strictly speaking, permeable products are hard pavers designed so water can flow through the joints between them. Porous and pervious surfaces include concrete and asphalt specially made to let water drain through the material itself, more like a sponge.
Consequently, all types of what's broadly called permeable paving are costlier alternatives to traditional methods.
The surfaces need to be cleaned regularly to remove leaves, sediment and other debris that can interfere with drainage. MORE STEPS
Other things you can do to reduce runoff:
• Mow properly to
encourage grass roots to absorb water better.
• Leave grass clippings on your lawn. As they break down, they add nutrients to the soil to feed the grass.
• Water wisely. Make sure sprinklers are watering plants, not surfaces such as driveways and sidewalks.
• Wash your car on the lawn instead of the driveway. The soapy water will be absorbed into the soil and cleaned naturally, rather than running into a storm sewer.
• Aerate your lawn periodically. Core aeration pulls plugs of soil out of the lawn, allowing oxygen, water and nutrients to reach grass roots.
• Test your soil. A soil test will tell you what your soil needs, so you don't add unneeded fertilizer that can wash off into bodies of water.