Okoboji Protective Association

The Storm Sewer Connection

What goes in comes out. Unlike a city sanitary sewer system that carries away household waste water, there are no treatment plants to remove pollutants from water in a city's storm sewer system.

When phosphorus-containing materials are washed or blown into our neighborhood streets, driveways, or parking lots, they quickly flow into the nearest storm water drain along the street. These pollutants are then carried through the underground pipes of the storm sewer system and are emptied directly into our lakes. And the phosphorus then becomes fuel for growth of excess weeds and algae.

For more information about the Clean Water Alliance, or how you can become involved, please call (712)336-3782 Ext-3.

Just one pound of phosphorus entering the storm sewer can grow 500 pounds of algae in our Iowa Great Lakes!

YOU can help keep the Iowa Great Lakes clean!!

Practice the simple tips on this webpage. People often do not realize that they are harming the Iowa Great Lakes. Most homeowners use up to ten times more fertilizers and chemicals per square foot than farmers!

Phosphorus from these products is the main culprit; it produces excess algae in the lakes. Aquatic plants, known as "algal blooms", cause the water to release an odor and to look green.

Once phosphorus enters a lake, it remains for many years. Therefore, preventing phosporus from entering the lakes is the most economical and practical way to keep algae under control.

LAWN & GARDEN

• Use low phosphorus fertilizers. Be sure to select a lawn and garden fertilizer with a phosphorus content of 0 (zero) (the middle number shown on the outside of the bag) unless a soil test shows a need for more.
• Follow proper application procedures. Fertilizers are very rate specific. Labels on lawn care products often list the rate at which the product should be applied. If not, do not guess!
• Keep fertilizer spray or pellets off pavement. Rain or lawn sprinkling will wash fertilizer off driveways or sidewalks and into the storm sewer.
• Keep lawn clippings and leaves off streets and lakes. By directing the discharge chute on your mower towards the interior of your lawn, you'll avoid blowing clippings into the streets and storm sewer system.
• Do not fertilize on frozen ground or before a heavy rain. Fertilizers will not soak in and will wash off your yard.
• Avoid using a grass catcher when mowing. Research shows that grass clippings left on your lawn are equal to one fertilizer application per year (it's natural and free).
• Leave grass height at 2 to 2 1/2 inches. Your lawn will withstand heat stress better, need less watering, and will discourage growth of dandelions and other weeds when left at that height.
• Quickly sod or seed on new construction sites. By stabilizing these sites immediately, you'll prevent soil and the pollutants it carries from being washed onto streets and into lakes.
• Use compost instead of fertilizer for enriching home gardens. Compost is more environmentally sound and provides a long lasting source of organic nutrients for vegetables and flowers.
• Leave a natural "buffer" at edge of lakes. A strip of taller grass and plants 5 to 10 feet wide will act as a buffer to absorb nutrient runoff before it reaches the lakes.
• Use pesticides and weed killers sparingly. Chemicals in runoff can be reduced by "spot spraying" problem areas rather than treating your entire lawn.
• Analysis on fertilizer bags is always in this order: nitrogen-phosphate-potash.
• Do not use any phosphorous fertilizer without first doing a soil test!
• Contact your local ISU Extension Service for soil testing information.

HOUSEHOLD

• Properly dispose of car oil, paints, and pesticides. Never dump motor oil, paints, solvents, pesticides, or other pollutants into the street, gutter, lake, or on your lawn.
• Use phosphorus-free soaps when washing your car. This will help to reduce the amount of phosphorus entering the storm sewer system from your driveway and street.

WHAT IS LOW IMPACT DEVELOPMENT?

Low Impact Development, or LID, is a new buzzword in urban planning, and refers to new and innovative approaches to minimize the environmental impacts of urban development and runoff on water quality.  Through a variety of small-scale site design techniques, LID controls runoff discharge, volume, frequency and quality to mimic predevelopment runoff conditions.

How does urban development and storm water runoff impact water quality?

Urban development impacts water quality in a number of ways. First, prior to construction, ground cover is usually completely removed, thereby exposing the soil surface to wind and water erosion. Second, heavy machinery compacts and hardens soils, diminishing its ability to absorb and filter water, even after it has been re-planted in grass or other vegetation. Third, with development comes replacing what was once vegetation with the hard surfaces of streets, driveways, parking lots and roofs. Hard surfaces shed water. As a result, the water that once was absorbed and filtered through the soil is now shed directly into our streets, storms sewers and into the receiving waters of lakes and streams with out any treatment.

What pollutants are contained in urban runoff?

Sediment from construction sites, nutrients from lawns, bacteria, grit and hydrocarbons from streets and parking lots are primary pollutants of urban runoff. Often raccoons and other animals live in storm sewers and their feces are washed into receiving waters during storm events.

LID offers a new approach to traditional storm water management- so what is the traditional approach to storm water development For years, city planners and engineers have designed streets and neighborhoods to shed storm water as quickly as possible, usually through buried pipes that dump untreated water directly into receiving waters. Additionally, storm water management has focused on holding gathered water in detention basins and throttling down the outflow. This strategy is applied on each development or employed on a regional basis. Outflows from these facilities are controlled to prevent downstream flooding. However, this approach only controls the rate of storm water runoff. It does nothing to treat water quality or reduce the total volume of runoff shed!

What can be done?

Silt fence ordinances can help control erosion from construction, but what is needed is a complete overhaul in how we think about urban planning and traditional storm water management, and that is what Low Impact Development is all about.

LID is a radically different approach to conventional storm water management and includes pollution prevention measures in site development to compensate for land development impacts on water quality and hydrology. LID functions by utilizing site design techniques that mimic the pre-disturbance natural hydrological regime to store, infiltrate, evaporate and detain runoff.

What is a rain garden? A rain garden is an example of what a homeowner can do on his or her own property to manage runoff. Rain gardens soak up water from your roof, driveway and lawn and are landscaped with deep-rooted native flowers adapted to wet conditions.

A rain garden is a contribution a homeowner can make to reduce urban pollution by storing runoff on their property and beautifying their yard at the same time.

For more information on rain gardens, contact Steve Anderson, NRC's Urban Conservationist, at 712-336-3782 Ext-3.

How can I find more information? Contact your local and county council members. Ask how you can get involved in land use planning.

Read more about LID online: The Low-Impact Development Center www.lowimpactdevelopment.org ;  Center for Watershed Protection: www.cwp.org ;  Conservation Subdivision Design: www.plannersweb.com/wfiles/w155.html