The Effects of Urban Runoff and the Implications for Beloit as an Ecosystem By Colin O Neil Introduction The City of Beloit, WI, has undergone a continual shift in population and developmental trends and these have tremendously affected the levels of urban runoff and stormwater release into area bodies of water and groundwater supply (Frisbee 2008). McKinney (2002) stated that the major challenge affecting conservation and preservation of ecosystems currently is the consistent growth of the urban core and urban sprawl. The growth and development of urban communities lead to increased amounts of both impervious surfaces and construction/development sites. The two major contributions to urban runoff, as defined by the Wisconsin Department of Natural Resources (DNR) (2008), are stormwater running off impervious surfaces and sediment-laden water flowing from development sites into streams and lakes. Through the close examination of these factors, city policies and ordinances, and current variables, the effects and impacts of urban runoff in Beloit can begin to be minimized (Frisbee 2008). Levels of urban runoff in Beloit greatly affect surface and groundwater quality and have tremendous implications for the private and public sphere including drinking water quality, home lawn care, fishing and recreation, construction, and road management (Wisconsin DNR 2008). Understanding Urban Runoff Beloit as an Ecosystem
Policies and Ordinances for Beloit, WI Urban Runoff in Beloit: Conditions and Current Efforts Future Goals and Actions Understanding Urban Runoff Urban runoff is a difficult environmental issue for municipalities to address because the source of the pollutants is diffuse, a condition referred to as nonpoint source pollution (WDNR 2008). Controlling for nonpoint source pollution is much more difficult because broad controlling measures must be taken instead of controlling for a single source (WDNR 2008). Gary Oberts (1977) of the Wisconsin Department of Natural Resources noted the major sources of stormwater pollution: combined sewage overflows, winter road salt and grit, street and construction debris, nutrient pollutants from livestock and fertilizer use, pesticides, atmospheric fallout, and deciduous leaf litter. During the course of daily activities, the pollutants listed above are deposited on impervious surfaces or on areas subject to erosion. In dry conditions, these pollutants build up for long periods of time and then during a heavy rainfall, they are released during a short period of time, producing highly concentrated runoff. This situation is referred to as a first flush, where a heavy rainfall or extreme weather event carries a majority of pollutants, most often discharging directly into bodies of water (Oberts 1977). The high volume of runoff creates a shock-load of pollutants in rivers, streams, and lakes (Oberts 1977). Instead of a slow introduction of contaminants, normal levels are rapidly forced out of balance during a first flush scenario. Shock-loads in waterways lead to oxygen depletion and immediately high toxic levels threatening entire ecosystems.
The major stream pollutant by weight and volume according to Oberts 1977 report for the Wisconsin DNR is sediment. Sediment can come from erosion, development sites, or deposition from motor vehicles. In addition to creating murky water conditions, sediment carries with it metals, pesticides, and nutrients which have a tendency to bind onto the soil particles (Oberts 1977). Nutrient input can lead to eutrophication, which is the depletion of oxygen in lakes and slow moving streams by oxygen demanding substances (Oberts 1977). Testing of lakes, rivers, and streams by municipal governments is needed to monitor levels of Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) in bodies of water to ensure the stability of normal oxygen levels. Beloit as an Ecosystem In order to understand the full effects of urban runoff, one must first investigate the natural and social characteristics of Beloit. Beloit is a post-industrial city located on the southern border of Wisconsin and Illinois (Burwell 2008). The city is bisected by its major body of water, the Rock River. Stormwater in Beloit discharges into the Rock River, Lenigan Creek, Turtle Creek, and Springbrook Creek (Frisbee 2008). The municipal drinking water comes from eight groundwater wells in the Beloit area (City of Beloit 2005). Four of the wells are located at depths of less than 200 ft, which are sand and gravel aquifers. The other four wells are deep sandstone aquifers between depths of 900 and 1200 ft (City of Beloit 2005). There is a lot of seasonal variability among climate and weather patterns in Beloit (Brinkmann 1997). Wisconsin on average can expect between 40 and 50 inches of snow
per winter and Beloit tends to be on the lower end of that spectrum (Brinkmann 1997). As Brinkmann (1997) describes, winter precipitation for Wisconsin is actually very low compared to total yearly statistics because 10 inches of snow is equivalent to one inch of rain. Snow becomes a factor because unlike rain it can build up into massive quantities and then thaw during warmer periods. This thaw creates a sudden surge of stormwater. Additionally, because the ground can take longer to thaw than the snow, melting water does not seep into the ground and instead is forced to flow over sidewalks, parking lots, lawns, and streets and carry with it pollutants and sediment. During the summer months, Beloit can expect hot and humid conditions with accompanying rain and thunderstorms. These storms also cause the same effect as thawing snow, although if minimal enough the water flows can be partly absorbed by vegetation and soil and filtration of pollutants can occur (Oberts 1977). The conditions within Beloit that create an environment for urban runoff are the large amounts of impermeable surfaces, poor levels of vegetation and construction sites. According to the City of Beloit Department of Public Works (2008) there are 185 street miles, 78 sidewalk miles and 28 parking lots within the city limits. These statistics only account for the impervious surfaces that fall under the department s jurisdiction. This does not include drive ways, houses, buildings, industrial facilities, and private parking lots. Therefore, there lies a potential for large volumes of urban runoff into Beloit s waterways unless properly addressed. During the beginning and middle of the twentieth century, Beloit was an industrial focal point in America, bringing commerce, factories and jobs (Burwell 2008). This boom led to a dramatic development of the city, turning its expansive prairie and
agricultural fields into immense factories, parking lots and road ways. At present, some factories in Beloit are abandoned, operate in a smaller capacity, or have moved closer to the interstate. Within city limits most parks and green spaces are characterized by open grass with trees. There are few examples of native prairie, rain gardens, or specific vegetation used to mitigate stormwater runoff in Beloit. Currently, local activist groups and conservationists such as Rob Baller, a conservation ecologist, have been working to save and reintroduce native prairie as well as mitigate erosion along the Rock River and other areas through out Beloit through the use of vegetation. In addition, Beloit College has begun to address runoff and stormwater utility directly on its campus. Clear examples can be seen in the plans for the new LEED-certified Beloit College Center for the Sciences which is set to open in the fall of 2008. The Center for the Sciences will include rain gardens, native prairie, a green roof, and a stormwater capturing system that will feed water into the greenhouse and indoor plumbing (Beloit College 2006). The City of Beloit has begun to address these issues to a certain extent, below is a discussion of current policies and city ordinances that tackle urban runoff and stormwater mitigation (Frisbee 2008). Policies and Ordinances for Beloit, WI There are many current state and local policies and ordinances that affect stormwater management at the municipal, industrial, and private level. The stormwater runoff policies instituted by the City of Beloit follow the recommendations and requirements set forth by the Wisconsin DNR (2006) and the Federal Environmental
Protection Agency (U.S. EPA). Below are a list and summary of pertinent ordinances and policies affecting the City of Beloit: 1. Wisconsin Pollutant Discharge Elimination System (WPDES) This program was organized by the Wisconsin DNR to target municipal, industrial, and animal waste releases into surface and ground water. Under this program, municipalities are required to apply for Municipal Separate Storm Sewer System permits (MS4). This permit system regulates the amount of pollutants being discharged by municipalities. http://dnr.wi.gov/org/water/permits/wpdes.htm 2. Construction Site Stormwater Permits The DNR requires permits for any construction site with one or more acres of land disturbance. This law is important because prior to 2006, there was no mandated level of treatment for stormwater before being released into bodies of water. Construction site erosion is a major contributor of stormwater pollution. http://www.dnr.state.wi.us/runoff/stormwater/constrforms.htm#brochure 3. Currently in accordance with the MSF permit, state law has mandated reduction requirements for Total Suspended Solids (TSS) in runoff. Beloit is now factoring in stormwater charges into monthly Beloit utility bills. The charges are dependent on family-size or in non-residential cases the total impervious area. The fees go directly towards funding reductions in stormwater TSS under the requirements of the MS4 permit. (for information on family size and charges see link below) http://beloit.govoffice3.com/vertical/sites/%7b4aecd64a-01fa-4c24-8f53- D3281732C6AB%7D/uploads/%7BBCF4723C-B3B7-4169-A37F- 7CB04956CCA7%7D.PDF In November 2006, Beloit applied for a MS4 permit under the WPDES. The permit requires that Beloit reduce by 20% its annual mass average of Total Suspended Solids (TSS) discharged from the MS4 to surface water as compared to implementing no stormwater management control by March 10, 2008 (WDNR 2006) TSS refers mostly to clays and silts, which as components of sediment carry metals, pesticides, and nutrients into water (Frisbee 2008). In compliance with the MS4 permit, the City of Beloit currently has reached a 21.2% TSS reduction (see Table 1.1) (Frisbee 2008). Under the WPDES, municipalities must have a 40% reduction in TSS by March 10, 2008 (WDNR
2006). As Bill Frisbee (2008) noted, a 40% reduction by 2013 will cost the City of Beloit a total of $4 million. The current stormwater charges on utility bills are aimed at raising revenue which will help address the $4 million needed to reduce TSS levels by 40% (See Urban Runoff in Beloit section below for more information on how TSS reduction occurs). The costs for Beloit to reduce TSS levels by 40% compared to other municipalities places Beloit in good economic and environmental standing. According to Bill Frisbee (2008), Storm Water Engineer for the City of Beloit, many other cities [of varying sizes] will require a much greater investment to reduce TSS levels by 40%. Green Bay, WI will need an estimated $18 million to achieve a 40% reduction and the city of Fon du Lac will require $18.6 million (Frisbee 2008). This price difference can be seen in yearly municipal stormwater utility charges. According to information collected by the American Public Works Association and the Wisconsin and Fox Wolf Watershed Alliance (2007) Beloit annual stormwater charges per utility bill are $30/yr compared to Fon du Lac which charges $56/yr and Green Bay which charges $55.20/yr. Residents in Appleton pay an extra $108.88/yr in stormwater charges on their utility bills. Urban Runoff in Beloit: Conditions and Current Efforts The MS4 permit requirements have begun a slow step towards mitigating stormwater pollution in Beloit. Presently the primary method for filtering stormwater pollutants are through detention basins or wet ponds (Frisbee 2008). Wet ponds (See image below) have been used in areas where stormwater pollution is worst. Wet ponds are designed patches of vegetation surrounding a permanent pool of water where
stormwater pollutants can be filtered before being discharged into waterways or groundwater (for more information on wet ponds visit www.stormwaterpond.com). Currently there are only a handful of wet ponds in Beloit (Frisbee 2008). The $4 million to be spent in the four years preceding the March 2013 deadline will be allocated mostly towards the construction and development of new wet ponds. Additional efforts include street sweeping, public education, and the installation of proprietary devices on stormwater pipes and underneath manhole covers. The city currently owns and operates one mechanical street sweeper and one vacuum sweeper (Frisbee 2008). Street sweepers are used to prevent pollutants on roadways from being incorporated in stormwater runoff. (Image of a characteristic wet pond or stormwater pond similar to one that would be seen in Beloit, courtesy of www.stormwaterpond.com) In the City of Beloit there are a total of 111 stormwater discharge drainage basins, which are areas of land where stormwater discharges, most lead directly to rivers or creeks (Frisbee 2008). Most drainage basins do not have detention basins or wet ponds
facilitating filtration. In areas without wet ponds, pollutants are only minimally filtered by existing vegetation if at all before being discharged into water. Frisbee (2008) noted that the major reduction of TSS will come from public education over any other means (See Future Goals and Actions section for more information). Unfortunately, the Wisconsin DNR specified modeling does not take public education into account as a viable means to reduce TSS because it can not easily be quantified. As shown in Table 1.1, the current levels of TSS are much lower than the 2006 levels when there were no controls used. The reduction can be attributed mostly to two controls: installation of wet ponds and the incorporation of proprietary devices on stormwater pipes under grates or manhole openings. A proprietary device is an apparatus installed on a stormwater pipe in an underground stormwater collection area. The main proprietary device used by Beloit is called a Snout (See image below), which is manufactured by Best Management Products, Inc. The snout is a plastic hood covering outfall pipes that prevents oils, some suspended solids, and floating debris/materials (such as plastic bottles, trash bags, etc.) from exiting the system (visit www.bmpinc.com for more information and video tutorials). All materials that are prevented from discharging are collected and removed every 2-3 months (Frisbee 2008). According to Frisbee (2008), Beloit is looking to install Snouts on all new stormwater pipe projects.
(Image of a Snout courtesy of www.bmpinc.com) Table 1.1 Tons of TSS being discharged to water by Beloit, WI. (Frisbee 2008) Year TSS (in tons) 2006 Levels (without controls) 1155 tons 2008 Levels (As of March 10, 2008) 879 tons (21.2% reduction) 2013 Levels (projected) 669 tons (40% reduction) To ensure that continual progress is being made in minimizing pollutants in the water, samples are being taken for the three main waterways in Beloit (Frisbee 2008). Samples test for BOD, COD, NH3, TSS, NO3, P, DO (dissolved oxygen), ph, and temperature (Frisbee 2008). The testing is also aimed at checking for illicit discharges into stormwater sewer pipes. Another effort by Beloit was switching a majority of road salt to a brine solution (Frisbee 2008). Salt Brine is a liquid mix of NaCL and H2O which is better for the environment that melts ice at temperatures below 15 F, which [solid] road salt often can not (Frisbe 2008). In addition to its current actions, Beloit is in the process of drafting a Stream Bank Erosion Plan that will address raising concerns
about erosion and sediment runoff into the Rock River and various creeks in Beloit (Frisbee 2008). Future Goals and Actions The solutions to urban runoff will come through many different actions. Fortunately, pressure from the U.S. EPA and the Wisconsin DNR has led to reduction requirements for TSS and stormwater pollutants have begun to decline. It will take the continual efforts of municipal government to correctly plan and execute viable stormwater systems as well as direct efforts towards re-vegetating areas and continuing public education. Bill Frisbee (2008) discussed many future goals for the cit of Beloit including: Increasing public education This will be the strongest and best way to mitigate runoff pollutants, because most solutions to stormwater pollution simply are not common knowledge yet, such as: o Do not use fertilizers with phosphorus o Do not wash your car in you driveway, wash it in your yard so the water and soap can be absorbed and filtered by the ground o Clean-up after your pets, stormwater can easily carry animal droppings directly into rivers and streams Increasing public partnership projects Creating a Stormwater Pollution Prevention Plan - This plan will educate businesses, industries and households about stormwater pollution and address clean-up procedures and disposal information in case of a toxic or pollutant spill.
Promoting infiltration of stormwater instead of simply diversion or detention techniques. Infiltration on development sites would reduce the detention requirements and ensure immediate absorption of stormwater. Continued monitoring and sampling of Beloit s river and creeks Constructing new wet ponds in the worst drainage basins of Beloit College Meeting the required 40% TSS reduction by March 10, 2013 Additional research and study will be needed to examine how beneficial a 40% reduction in TSS will be for Beloit s water quality and what effect this will have on Beloit as an ecosystem. With the new science center at Beloit College, hopefully there will be a spike in interest surrounding urban runoff prevention and solutions. Finally, while large strides have been taken by the City of Beloit, local action groups, students, and sustainability initiatives like the Rock River Coalition will have to place continual pressure on the issues surrounding urban runoff and its effects on surface and ground water. Through continual pressure by these groups and organizations, local and state government will continue to place an emphasis on minimizing the effects urban runoff and mitigating stormwater pollution.
Works Cited American Public Works Association Wisconsin and Fox Wolf Watershed Alliance. 2007. Stormwater user charge system information. American Public Works Association Wisconsin and Fox Wolf Watershed Alliance. Beloit College. 2006. Campaign news. http://www.beloit.edu/~alumni/giving/about/news.php (February 17, 2008) Burwell, F. (2008). Personal interview with the Beloit College Archivist. (February 21, 2008) Brinkmann, W.A.R. 1997. Challenges of Wisconsin s weather and climate. Pages 49-64 in Ostergren, R.C. and T.R. Vale (editors) Wisconsin land and life. University of Wisconsin Press, Madison. City of Beloit Department of Public Works. 2006. Statements and goals 2006. http://www.ci.beloit.wi.us/vertical/sites/%7b4aecd64a-01fa-4c24-8f53- D3281732C6AB%7D/uploads/%7B1AABC4E9-75BC-46DA-BD74-032C040AE2FF%7D.PDF (February 20, 2008) City of Beloit. 2005. Year 2005 drinking water quality report. http://beloit.govoffice3.com/vertical/sites/%7b4aecd64a-01fa-4c24-8f53- D3281732C6AB%7D/uploads/%7B846AF17F-F9F6-45EE-BBD5- FB13FCFD2E68%7D.PDF (February 22, 2008) Frisbee, W.A. (2008). Personal interview with the Storm Water Engineer for the City of Beloit. (February 22, 2008) McKinney, L.M. Urbanization, biodiversity, and conservation. 2002. BioScience 52:10: 883-890.
Oberts, G.L. 1977. Water quality effects of potential urban management practices: a literature review. Technical Bulletin No. 97. Wisconsin Department of Natural Resources., Madison, WI. U.S. EPA. 2007. Model ordinances language. http://www.epa.gov/owow/nps/ordinance/osm6.htm (February 22, 2008) WDNR. 2006. General permit to discharge under the Wisconsin Pollutant Discharge Elimination System WPDES Permit No. WI-S050075-1. State of Wisconsin Department of Natural Resources. WDNR. 2008. Urban runoff. http://www.dnr.state.wi.us/org/gmu/lowerrock/basinissues.html#urbrunoff (February 15, 2008)