Zoning and Building Safety Department 
Stormwater Management

Frequently Asked Questions

What is storm water?

The flow of water that results from precipitation and which occurs immediately following rainfall or as a result of snowmelt. When a rainfall event occurs, several things can happen to the precipitation. Some of the precipitation infiltrates into the soil surface, some is taken up by plants, and some is evaporated into the atmosphere. Stormwater is the rest of the precipitation that runs off land surfaces and impervious areas. Stormwater discharges are generated by precipitation and runoff from land, pavements, building rooftops and other surfaces. These hardened surfaces are called ‘impervious surfaces’ and they do not allow rainfall to infiltrate into the soil surface like natural vegetation, so more of the rainfall becomes stormwater runoff. Storm water runoff accumulates pollutants such as oil and grease, chemicals, nutrients, metals, and bacteria as it travels across land. Heavy precipitation or snowmelt can also cause sewer overflows that may contaminate water sources with untreated human and industrial waste, toxic materials, and other debris.

Where does the storm water go?

Storm water that does not evaporate or seep into the ground drains into over miles of underground storm sewer pipe that carry surface runoff to the Mississippi River (and in some areas Sugar Creek and Rock River). Every time it rains, thousands of gallons of storm water enter our storm sewer system. As the runoff flows across lawns, driveways, parking lots and streets, it collects pollutants.

What type of materials can I use for fill material?

Approved Fill Material is defined as uncontaminated, nonwater-soluable, nondecomposable inert solid material. Clean fill includes soil, rock, stone, dredged material, used asphalt and brick, block or concrete masonry units (CMUs) that have been broken so as not to become “critter condos”, used concrete that has been broken into pieces smaller than 12”X12”X12” with no protruding bar from construction and demolition activities that is separate from other waste and recognizable as such. Unused asphalt would not meet the definition of clean fill.

What is storm water pollution?

Many people think that pollution in our streams, rivers and lakes only comes from industrial facilities or wastewater treatment plants. Even if all these sources of pollution were eliminated, much of the pollution would still remain.

The remaining source of pollution that is not caused by specific, identifiable sources are called non-point source pollution. Typical pollutants include litter; sediments from exposed soil, pet waste, detergents, pesticides and fertilizers from lawns and gardens, paints, oil, grease and toxic chemicals from motor vehicles, road salts, and household hazardous wastes.

When these materials are improperly used or disposed of, they can be picked up by storm water runoff as it flows across streets, parking lots and lawns. After this storm water runoff travels through the storm sewer system, it is discharged to receiving waters without any treatment. As a result, any pollutant that is dumped on the ground can end up in our creeks, rivers and lakes.

There are serious problems associated with polluted storm water. The pesticides, bacteria and chemicals that may be present in polluted storm water can pose a health risk to people. Aquatic plants and animals living in streams and rivers may become sick or die from contact with polluted storm water. Clogged catch basins can be unsightly and can cause flooding problems.

Since storm water is naturally channeled to or flows through underground pipes to to the Mississippi River (and in some areas Sugar Creek and Rock River). There is no opportunity for treatment to remove pollution. So, each of us must be careful to minimize or eliminate substances which may inadvertently pollute our waterways when it rains.

What rules and regulations control stormwater issues?

Illinois Drainage Law, NPDES regulations, and the Rock Island County Stormwater Ordinance are the main stormwater rules and regulations.

My neighbor’s stormwater runs on my property, can I divert it?

No. If the natural drainage is from their property to your property, then you cannot block the natural flow of the storm water.

Can I change how stormwater flows across my property?

Yes as long at the stormwater enters and leaves your property at the same locations as it does naturally. Also you cannot unreasonably increase the flow of the stormwater.

There is a ravine/stream through my property; who is responsible to maintain it?

Most ravines and streams are on private property. The property owner is responsible to maintain the ravine/stream to prevent or reduce the discharge of pollutants. This maintenance shall include, but is not limited to, sediment removal, bank erosion repairs, maintenance of vegetative cover, and removal of debris from privately owned pipes and structures.

There is a swale or open drainage channel through my property; who is responsible to maintain it?

The property owner is responsible for maintenance of private drainage channels, including keeping the drainage channel free of trash, debris, excessive vegetation, and other obstacles that would pollute, contaminate, or retard the flow of water through the drainage channel. In addition, the owner shall maintain existing privately owned structures adjacent to the drainage channel.

Can I put yard waste, tree limbs, compost, concrete, chemicals, etc. into my ravine?

No. It is a violation of the storm water ordinance to release contaminates into the storm water. Common contaminates include trash, yard waste, stones, earth, concrete, wood, lawn chemicals, pet waste, wastewater (grass clippings), oil, petroleum products, cleaning products, paint products, hazardous waste and sediment.

Why can’t I dump my natural material (yard waste, sticks, compost, etc.) into my ravine?

These materials get picked up during storm events and are carried into the drainage channel where they cause blockages of the drainage channel, pipes, and culverts. These blockages can cause flooding at downstream properties.

What is a rain garden?

A rain garden is an attractive garden with a special purpose—to reduce the amount of stormwater entering our beautiful streams, rivers and lakes. A rain garden is constructed as a place to direct the rain from your roof or driveway and is landscaped with plant species native to our region.

What is NPDES Phase II and Who is Affected?

Storm water runoff has been a source of great concern for many years. It can pollute lakes and streams. As a result, the 1987 amendments to the Clean Water Act required the United States Environmental Protection Agency (U.S. EPA) to address storm water runoff in two phases. Phase I of the NPDES Storm Water Program began in 1990 and applied to large and medium municipal separate storm sewer systems (MS4) and 11 industrial categories including construction sites disturbing five acres of land or more. Phase II of the NPDES Storm Water Program will begin in March 2003 and applies to additional MS4s and construction sites disturbing equal to or greater than one but less than five acres of land. Phase II also expands the industrial "no exposure" exemption covered under Phase I. Illinois Environmental Protection Agency (Illinois EPA) is in charge of implementing both phases of the NPDES Storm Water Program.

How Do the Phase II Rules Affect Industry?

Phase I of the storm water program required 11 industrial categories to obtain an NPDES permit for their storm water discharges. Phase II does not add any new industrial categories to the program.

Phase I also included a "no exposure" exemption limited to certain "light industry" facilities. Phase II expands the "no exposure" exclusion to include all industrial facilities covered under Phase I except construction activities. If industrial materials or activities are not exposed to storm water, an exemption can be requested under this exclusion. Illinois E PA notifies exemption applicants if the exemption is approved or if the request is denied or additional information is required. The condition of no exposure must be maintained by keeping all industrial materials or activities protected at all times. If "no exposure" conditions are not maintained, the operator must immediately apply for an NPDES storm water permit. For a list of the Phase I "light industry" facilities, contact the Office of Small Business.

Under the Phase II "no exposure" exclusion, a written certification must be submitted every five years to verify that a condition of no exposure exists. All industrial facilities covered under Phase I of the storm water program must either apply for an NPDES permit or complete a "no exposure" certification form every five years in order to comply with storm water requirements. The Illinois EPA fact sheet entitled "Storm Water — Keep it Clean!" presents additional information.

How Do The Phase II Rules Affect Construction Sites?

Phase II of the storm water program automatically applies to all construction activities disturbing one or more acre to less than five acres of land. These sites must receive an NPDES permit before any earthmoving activities begin. Illinois EPA may require construction sites disturbing less than one acre of land to obtain a storm water discharge permit if such activities would adversely affect water quality.

In order to comply with Phase II of the storm water program, follow the steps below:

1. Determine which parties are considered "operators" responsible for complying with the Phase II requirements.
2. Complete and submit a Notice of Intent (NOI) to the Illinois EPA Division of Water Pollution Control Permit Section before construction activities that will cause land disturbance begin.
3. Develop a storm water pollution prevention plan (SWPPP) prior to the start of construction. The SWPPP does not need to be submitted to Illinois EPA, but must be kept on the construction site and accessible to everyone during construction activities.
4. Implement the SWPPP, including completion of inspection reports that must be kept on site. Complete final stabilization of the site.
5. Complete and submit a Notice of Termination (NOT) to Illinois EPA when any of the following occurs:
   • After the land disturbing activities are complete and the site has been finally stabilized, the operator should terminate his coverage under the permit by completing a NOT form and submitting it to the Illinois EPA. The United States Environmental Protection Agency considers that a site has been finally stabilized when all land disturbing activities are complete and a uniform perennial vegetative cover with a density of 70 percent of the cover for unpaved areas and areas not covered by permanent structures has been established or equivalent permanent stabilization measures have been used.
   • The permittee is no longer an operator of the site.
   • For residential construction only, after temporary stabilization has been completed and the homeowner has been informed that he or she must complete final stabilization upon assuming control of the site.
    

For more information on how to comply with the storm water program, see Illinois EPA’s fact sheet "Storm Water Management for Construction Activities." More information about NPDES storm water permits and assistance on filling out NOIs can be obtained by contacting the Illinois EPA Office of Small Business.

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