By Cathy Rofshus, Making Waves

Editor&8217;s note: This is the second in a three-part series on controlling stormwater runoff. This first column focused on what individual homeowners in urban areas can do to help improve water quality. This one will focus on what businesses and developers can do in urban areas to reduce pollutants in stormwater runoff.

As raindrops fall in Albert Lea, they hit hard surfaces such as roofs, sidewalks, streets and parking lots. Oftentimes, the rain drops travel directly from those surfaces to a storm sewer. In Albert Lea, all storm sewers &8212; those gutters in the street &8212; drain to a local lake, whether it&8217;s Fountain Lake, Pickerel Lake, Lake Chapeau, Goose Lake or Albert Lea Lake.

All the raindrops together make up stormwater, or runoff.

As the raindrops drain to the storm sewers, they pick up pollutants such as soil, ice melt and oil.

That&8217;s how a parking lot on West Main Street can affect Fountain Lake and a store roof on East Main Street can affect Albert Lea Lake, even though they are several blocks from the water.

The Shell Rock River Watershed District is working with property owners and the city of Albert Lea to reduce pollutants in stormwater running off the roofs, parking lots and streets of the Jobs Industrial Park. With water retention areas &8212; properties that are landscaped to catch and hold rainwater &8212; the Shell Rock River Watershed District will &8220;control the first drop.&8221; This means catching those raindrops before they carry pollutants downstream to Albert Lea Lake and the Shell Rock River.

As the community works to improve local lakes, it will start to look to businesses and developers to play a bigger role. Here are some ways that businesses and developers can control the first drop and help make healthier lakes for a healthier community.

Construction sites: It&8217;s critical to control sediment and prevent erosion on construction sites. The U.S. Environmental Protection Agency estimates that 20 to 150 tons of soil per acre runs off construction sites with rain water.

While putting in silt fences and other control measures costs money and time, it&8217;s much cheaper to keep the soil out of lakes than dredge it out later. Studies have shown that for every $1 not spent on erosion control, $14 to $15 is spent on correcting the impact.

For more information on sediment control, call watershed conservationist Andy Henschel at 377-5785. These Web sites are also helpful:

Stormwater Management Resource Center: www.stormwatercenter.net

Minnesota Erosion Control Association: www.mnerosion.org/

Pollution Control Agency: http://www.pca.state.mn.us/water/stormwater/index.html

Pervious Pavement and Pavers: More and more businesses are using pervious concrete, asphalt and pavers.

Here is how The Concrete Network describes this concept:

&8220;As more available land area in the country gets paved over, a larger amount of rainwater ends up falling on impervious surfaces such as parking lots, driveways, sidewalks, and streets rather than soaking into the soil. This creates an imbalance in the natural ecosystem and leads to a host of problems including erosion, flash floods, water table depletion, and pollution of rivers, lakes, and coastal waters as rainwater rushing across pavement surfaces picks up everything from oil and grease spills to deicing salts and chemical fertilizers.

&8220;Instead of preventing infiltration of water into the soil, pervious concrete assists the process by capturing rainwater in a network of voids and allowing it to percolate into the underlying soil. In many cases, pervious concrete roadways and parking lots can double as water retention structures, reducing or eliminating the need for traditional stormwater management systems such as retention ponds and sewer tie-ins.&8221;

While more expensive than traditional concrete and asphalt, pervious surfaces can reduce the cost of stormwater control. They definitely reduce the environmental impact &8212; and the economical cost of restoring our waters &8212; in the long term.

For more information, try these Web sites:

www.concretenetwork.com/pervious/

www.minnehahacreek.org/

Rain Barrels and Cisterns: Factories and other businesses can use rain barrels and underground cisterns to capture rainwater running off roofs and parking lots. Think of the some of the large stores and factories in our community and you can begin to understand the potential impact to local waters. The rain barrels and underground cisterns capture rainwater that can be used later for watering turf and landscaped areas.

Plant trees: A mature tree canopy can intercept 1,600 gallons of rainwater a year. Planting trees along parking lots improves the aesthetics of our community, provides shade for customer and employee vehicles, and can serve as windbreaks and living snowfences.

Green roofs: Believe it or not, people are starting to use vegetated roof covers. This new technology is quickly evolving in the United States, including the Minneapolis-St. Paul area. Business and homeowners use a special growing media on rooftops to establish hearty plants to catch and hold rainwater. Not only do green roofs reduce stormwater runoff, they provide roof insulation, dampen noise, and create an attractive look.

Trivia question:

How much runoff does a 1,000 square foot area (roughly the size of a driveway) generate in year?

A. 12,100 gallons of rain water

B. 6,500 gallons of rain water

C. 3,250 gallons of rain water

The answer is A. 12,100 gallons, according to the Ramsey-Washington Metro Watershed District.

Cathy Rofshus is the outreach director for the Shell Rock River Watershed District. She can be reached at 377-5785.