Community Guide to Development Impact Analysis by Mary Edwards

Introduction Fiscal Traffic Socio-Economic Environmental Putting it Together Cost of Community Services

Environmental Impact Analysis

Local officials, planners, and developers increasingly recognize that economic development and environmental quality are equally important components of community growth. Unfortunately, this awareness comes after decades of environmental neglect: sprawling development beyond urban boundaries, rapid and irreversible conversion of prime agricultural land, loss of unique plant and animal communities, and increased pollution of water and air resources. It goes without saying that development often has substantial impacts on the quality and quantity of a community’s air, land, water, and biological resources; yet, economic development often takes precedence over environmental protection. 

The benefits of economic development are often more immediate, important, and obvious to community members and local officials: the creation of good-paying jobs; provision of affordable housing; and diverse shopping opportunities satisfy many of the priority needs and desires of local consumers. The benefits of environmental protection are often less evident and immediate, but are nonetheless important as natural resources continue to become scarce and threats to environmental and human health are ever-present. Yet, tradeoffs between economic development and environmental protection need not continue as Wisconsin communities continue to grow. 

The purpose of this chapter is to help community members and local officials take a leadership role in ensuring that future development reflects environmental protection as well as fiscal, social, and economic community goals. This chapter defines environmental impact assessment; explains reasons for conducting an impact assessment; discusses who should be involved in the process and the limitations of the process; and provides guidance on how to conduct an environmental impact assessment. 


Community environmental impact assessment provides a systematic process for identifying, describing and evaluating community natural and human resources in order to improve decisions about their management. Choosing to assess the community environment does not imply that all identified resources must be preserved or protected. It does imply that the community must be knowledgeable about its resources, so that development decisions reflect the range of community values, not just economic values. An environmental impact assessment facilitates community planning by assisting local government officials, community leaders, and citizens: 


The environmental impact assessment process requires input from a variety of individuals including: professionals and civil servants with expertise in environmental science and engineering; local officials who are knowledgeable of local, state, and federal environmental management procedures and regulations; and members of the community who possess both expertise and interest in the local environment and natural resources. 

Naturally, the developer, planner, local officials and perhaps a hired consultant should be involved in the process. Because the environmental impact assessment process often requires technical expertise and consideration of numerous environ-mental compliance issues, it is appropriate to involve other individuals such as an engineer, land or ecological conservation expert, state agency staff (e.g., Department of Natural Resources). Local conservation organizations such as land trusts and conservancies as well as the local offices of national organizations such as The Nature Conservancy are often an excellent source of information about local environmental concerns, community biological resources, and conservation tools. 

Selecting the appropriate individuals to be involved in the assessment will ensure that more adequate (and accurate) consideration is given to potential impacts associated with the development. The up-front investment made in identifying and engaging relevant participants in the process will pay off in the long run as potentially costly mistakes in planning and estimating impacts are avoided. 


Including an environmental analysis component in the overall development impact assessment process can: 

For example, an environmental impact assessment can inform development decisions about the most suitable site for a housing development. While economics often drive such decisions, an environmental impact assessment can provide the stepping stone for exploring alternative sites that would minimize farmland conversion or other environmental impacts. 

An environmental impact assessment can also aid in developing mitigation strategies for proposed development that are approved (e.g., site design elements that reduce storm-water runoff volume or contamination). This is particularly useful since it is typically much easier to prevent problems from occurring in the design of the development than correcting problems after the development is built. 


An environmental impact assessment provides general information about the potential for adverse environmental impacts associated with a proposed development, not detailed quantitative information for design or regulatory purposes (e.g., could indicate areas where private on-site waste disposal may become a groundwater problem, not what density of housing will exceed contaminant attenuation capacity). Design standards and regulations typically require models with much greater data requirements. 


This chapter outlines five phases of preparing an environmental impact assessment. It is expected that each of the five phases will be adapted to meet the specific assessment needs of the community, therefore the following discussion is intended to provide only an outline of general procedures for conducting an environmental impact assessment. 

Before proceeding with the environmental impact assessment, however, an important first step is to obtain a map of the proposed development and if possible, a map of the community. Maps are useful tools for visualizing how a proposed development “fits” into the layout of the community. The various types and sources of map information available to communities are discussed later in this section. 

A worksheet is provided to assist in completing the environmental impact assessment. Depending on your community’s needs, all or portions of the information provided will be useful to your assessment efforts. For example, if a list of all relevant environmental guidelines and standards has already been compiled by a local agency or organization, it is not necessary to duplicate efforts. 

  1. Define the scope of the Environmental Impact Assessment; 
  2. Inventory community natural resources, their quality and current use; 
  3. Compile and review existing community environmental management standards and guidelines; 
  4. Assess the extent and significance of environmental impacts resulting from the proposed development; and 
  5. Evaluate the potential cumulative impacts associated with the proposed development

Phase 1:  Defining the Scope of the Environmental Impact Assessment

Similar to fiscal, social and economic impacts, development impacts on the environment vary significantly by project type, size, location, and the environmental conditions at the proposed site. As such, the first phase of environmental impact assessment involves becoming familiar with the characteristics of the proposed development. The better understanding one has about the project, the more accurate will be the assessment of environmental impacts. In designing the environmental impact assessment, it is important to consider the following unique characteristics of the proposed development site: 

Phase 2:  Inventorying Community Natural Resources, Their Quality and Current Use 

Once elements of the proposed development are understood, inventorying community natural resources, their quality and current use is an important next step in determining what impact a proposed development may have on the community’s environment. Moreover, an environmental inventory can provide citizens with a better understanding of local natural resources, economic opportunities for resource use, factors that might constrain development and problems that might result from resource use or new development. The inventory of current use and quality of natural resources in the community can either be specific to the proposed development or may include a comprehensive assessment of the community’s natural resources. 

There are many aspects to consider in preparing an inventory. For example, a community may choose to protect a resource that is currently “useful” or of “high quality” from even the most minimal impacts. Other sources may lend themselves to a variety of functions without noticeably degrading the local environment. It is important to keep in mind that each resource may be affected by certain types of development pressures, but not by others. Finally, the inventory should include not only existing resources, but also threats to those resources (e.g., loss of prime agricultural land or open space) and citizen concerns about the quality of those resources (e.g., quality of drinking water supply). Box 5.1 provides an overview of environmental resources and potential impacts associated with development. Development may also affect a community’s environment by impacting the aesthetic quality of a community, an issue further addressed in the Socio-Economic chapter of this guide. 

Box 5.1: Environmental Resources and Potential Impacts of Development 

Land Resources: 

     Loss of Plant Species and Communities: Direct impacts result from: disturbances that cause changes in temperature, light, moisture, and nutrient levels; removal activities (e.g., clearcutting, bulldozing); impacts resulting from air and water pollution (e.g., turbidity, eutrophication). Indirect impacts result from changes in natural community processes (e.g., fire) or invasion of non-native plant species. Loss of plant communities also results in decreased water quality (e.g., loss of filter function associated with plant communities), increased erosion as a result of unstable soil, nutrient imbalances in the soil, and/or compaction of soil.
     Loss of Wildlife and Wildlife Habitat: Like plant communities, wildlife habitat may be impacted both from direct and indirect activities associated with development. Alteration, fragmentation, or destruction of wildlife habitat can result in the direct loss or displacement of species and the ability of the ecosystem to support other biological resources such as the plant communities upon which the wildlife relied for survival. 
     Loss of Other Natural Resources: Loss of natural resources such as quality water supply, clean air, forests, mineral resources, wetlands, farmland, game species, rare species and recreation opportunities can impact a community’s ability to sustain itself over the long term. 
     Soil Erosion: Construction activities are of particular concern. Soil erosion is an important problem both at its source and downstream of the development site. Lost soil will be deposited somewhere, and the location of the deposition could alter downstream hydrology and increase flooding. It may also pose a water quality issue directly as a result of siltation and indirectly from contaminants carried with or attached to soil particles. 

Water Resources 

     Surface and Groundwater Hydrology: Changes in surface hydrology alter the flow of water through the landscape. Construction of impervious surfaces such as parking lots, roads, and buildings increase the volume and rate of runoff, resulting in habitat destruction, increased pollutant loads, and flooding. Built or paved areas and changes in the shape of the land also influence groundwater hydrology (i.e., recharge rates, flow, conditions). 
     Water Quality: Development activities (e.g., construction, industrial or residential development) as well as the spillover effects of development such as increased demand for drinking water and increased auto use can impact water quality by contributing sediment, nutrients, and other pollutants to limited water supplies, increasing the temperature of the water, and increasing the rate and volume of runoff. 
     Aquatic Species and Communities: Changes in surface hydrology and water quality can have adverse impacts on aquatic species such as fish, plants, and microbes. Increased turbidity, temperature, velocity of flow, and pollutant loads can have direct impacts on the species and their habitat. 

Air Resources: Air pollution has direct and potentially hazardous impacts on human health. Air pollution includes two types: gas emissions, and particulate emissions. Non-hazardous, yet undesirable air pollution includes odors produced from certain manufacturers and fast food restaurants, etc. 

Noise: Noise pollution can have a significant impact on both human health and quality of life for the residents of a community. Such pollution is most commonly associated with airports, highway and interstate traffic, large industrial facilities, and high volumes of truck and auto traffic on city streets.

Methods for Inventorying Natural Resources, Their Quality and Current Use 

Gathering information should not require the community to invest substantial resources in collecting original data about the local natural resources. Rather, the inventory process should involve the collection of existing information, which has already been collected by various agencies and organizations (e.g., Department of Natural Resources, the University of Wisconsin system, conservation groups). 

However, if there is no existing data, it may be possible to obtain the support of University researchers or a local conservation organization in inventorying the environmental resources at a particular site. Professors, graduate students, or local conservationists may be willing to pursue research projects such as conducting a biological inventory of the site, collecting environmental attribute data for the development of a GIS database, or surveying community concerns about a proposed project. 

The three methods for gathering environmental assessment information outlined in this chapter include: Geographic Information Systems, Community Resources, or a Worksheet Approach. 


The evolution of geographic information system (GIS) development and application to natural resource issues in Wisconsin has made it possible for researchers, agencies, local communities and others to compile inventories of natural resources, assess threats to those resources and apply such findings to planning efforts. In fact, many local governments are beginning to use GIS to perform more complex analytical functions that reach beyond inventorying natural resources such as identifying land suitability for certain types of development. Some types of information currently being entered into and used in GISs include data on land ownership, soils and land use in Wisconsin. A list of potential sources of geographic information is provided below. 

If a decision is made to use digital geographic information, it is important to ensure the high quality and accuracy of data sets and/or data layers; compatibility with other data used in the environmental impact assessment; and avoidance of other potential limitations such as time dependent data or inaccurate projection and scale of GIS products. 


The Wisconsin Land Information Program:
Wisconsin Land Information Association: 
Department of Natural Resources Geographic Services Section (GEO): 
Wisconsin Interagency Land Use Council: 
Wisconsin State Cartographer’s Office: 
Land Information and Computer Graphics Facility:


Community members are often the most useful source of information and expertise about local natural resources, environmental concerns, and the potential impacts associated with a proposed development. Residents are often familiar with local landforms, wildlife, and land use patterns. For example, a farmer who’s land is being surveyed for possible development may be aware of nesting grassland birds that are currently protected by federal law. Such information is critical to the environmental impact assessment. 

In addition to the technical and scientific aspects such as calculating the increase in storm-water runoff from a proposed development, community perceptions, values  and opinions about the types of development are also important. A proposed development may be technically feasible and consistent with past development practices in the community; however, community input is the most reliable source of information for determining whether the project is compatible with the community’s long-term goals. A preliminary list of survey questions for gathering information from community members about the potential environmental impacts of a proposed development is provided below. This list is not meant to be exhaustive; users are encouraged to add questions where appropriate. 


For communities that may not have existing GIS capabilities, a less-technical guide to use in the preparation of the inventory is a series of Environmental Resources Inventory worksheets developed by the University of Wisconsin–Extension, Environmental Resources Center. Assistance with this method of inventory is available through your county Cooperative Extension office or the UW Environmental Resources Center. The worksheets provide descriptive information about various resources and what aspects of the resource may be impacted by development. They also provide a systematic method for collecting information about the resource, which can be particularly useful in evaluating specific impacts and determining whether to proceed with the proposed development. A list of the categories for which worksheets have been developed is provided below. 

  • Aesthetic Qualities 
  • Cultural Features 
  • Human Health/Environmental Hazards 
  • Waste Reduction 
  • Geographic Setting/Soil and Mineral Resources 
  • Surface Water Resources/Water Supply 
  • Groundwater/Water Supply 
  • Plant Communities 
  • Wildlife and Wildlife Habitat 

The worksheets developed by the University of Wisconsin–Extension are accompanied by specific and thorough background information on each of the resources mentioned above. 

  • What are the important natural resources in the community (e.g., water supply, agricultural land)? Why? To whom are they most important? 
  • What are the major threats to natural resources in this community? 
  • How do citizens in the community feel local natural resources should be managed (e.g., water usage, scenic waterways, air quality, hazardous waste management)? 
  • Is the general environmental ethic in your community one that encourages limits on use of natural resources or one that promotes unlimited use? 
  • What is the connection of land use in the area to history and culture? Would the proposed development enhance or threaten that connection? 
  • Has the community ever experienced a time of scarcity for any of its natural resources? If so, what were the effects? Would the proposed development contribute to the potential for scarcity? 
  • In your opinion, would any secondary effects of the proposed development pose any threat to the community’s environ-mental resources?

Sources of Information for the Inventory 

Agencies at all level of government are useful sources of information for the community inventory. Expertise and technical assistance within the various levels of government vary across a wide range of issues, including planning, environmental compliance and protection, geographic information and mapping. Depending on the needs of the community in gathering information for the environmental assessment, it may be prudent to browse through several of the websites referenced in the following list of sources. The list includes local and area offices, State agencies and the university system, and Federal agencies involved in environmental protection and management. 




Phase 3:  Compiling and Reviewing Existing Community Subdivision Ordinances and Environmental Management Standards, Regulations and Guidelines 

An environmental impact assessment should also reflect the extent to which community natural resources, human and environmental health, and aesthetics are protected by existing subdivision ordinances and environmental management regulations and guidelines. Before a proposed development can begin, both the developer and local officials need to ensure that the development will comply with federal, state, and local environmental regulations, subdivision ordinances and any other local plans such as master or long-range plans. The Wisconsin Department of Natural Resources is an excellent source of information on federal and state requirements and the county planning agency or other local government agency will be able to provide necessary information on local standards. 

Wisconsin and National Environmental Policy Acts (WEPA and NEPA) 

While environmental impact assessment guidelines exist at the state and federal levels, communities cannot depend on state or federal regulations to require developers to complete an environmental impact analysis. The Wisconsin and National Environ-mental Policy Acts (WEPA and NEPA) only require evaluation of impacts from developments funded by the state or federal government or which require state or federal permits and have the potential to cause significant adverse environmental impacts. WEPA and NEPA require state or federal agencies to prepare an Environmental Impact Statement for “major actions significantly affecting the quality of the human environment.” For example, an EIS might be required for the development of high-ways, new buildings, projects which include government financing and projects which require government permitting. These policies cannot be used to stop, approve or modify projects on their own, but the environmental impact statement may indicate where other environmental regulations may be violated by the project. 

Locally or privately funded projects are not required to submit a WEPA or NEPA impact evaluation. However, there are many other state and federal regulations which govern management of designated land categories and activities associated with some kinds of development. These cover topics such as wetland and shoreland protection, flood control, discharge of water and air pollutants from facilities, storm-water management, hazardous waste management, farmland protection, and protection of threatened and endangered species. Communities are advised to deter-mine which environmental statutes might apply to properties within their community as part of an initial site inventory. An environmental consultant can assist the community in identifying concerns specific to their project. 

State, County, Local Subdivision Ordinances 

As discussed earlier in this chapter, the local subdivision ordinance (or county ordinance if no local ordinance is in effect) requires the developer to comply with local, state and federal environmental regulations regarding such issues as storm-water management, construction site erosion, floodplain and wetlands protection. Wisconsin Statute, Chapter 236 provides general guidelines and requirements for platting lands, recording and vacating plats, while county and local ordinances may specify requirements for considering the environmental impacts associated with each pro-posed development. For example, the Dane County, Wisconsin Land Division and Subdivision Regulations (Title 14, Chapter 75, Dane County Ordinances) specifically mandates that, in addition to preparing a plat (map) of the proposed subdivision, the subdivider shall comply with all applicable ordinances, statutes, regulations and plans, including but not limited to, State regulations regarding floodplain management, all county ordinances and regulations, and all master plans and master plan components. To gather additional detail on the Dane County ordinance and regulations, visit the County’s website at

Wisconsin Statute, Chapter 236, Platting Lands and Recording and Vacating Plats. 

Purpose: “ regulate the subdivision of land to pro-mote public health, safety and general welfare; to further the orderly layout and use of land; to prevent the over-crowding of land; to lessen congestion in the streets and highways; to provide for adequate light and air; to facilitate adequate provision for water, sewerage and other public requirements....” 

Delegation of Authority: To achieve the above stated purpose, Section 236.45, Local subdivision regulation, specifically delegates power to, “...any municipality, town or county which has established a planning agency...” to “...adopt ordinances governing the subdivision or other division of land which are more restrictive than the provisions of this Chapter [236]. 

Source: To obtain details of this and other Wisconsin Statutes, visit the State’s legislative website at

In addition to county level ordinances, local ordinances may also specify the extent to which environmental impact assessments are required for proposed developments. For example, the City of Middle-ton in its Subdivision Ordinance (Revised August 1992), specifically requires the sub-divider to conduct an environmental assessment of the proposed development. The assessment includes a checklist, to be completed by the subdivider, indicating changes in land, water, and biological resources among other factors. 

Box 5.5 includes a copy of the City of Middleton’s Environmental Assessment Checklist. If the proposed development will affect a change in any resource identified in the checklist, the subdivider must provide a written explanation and supportive documentation describing the impacts of the proposed development. The assessment is then reviewed by the Plan Commission, which may, in turn, determine a need for and require an expanded environmental assessment of the subdivider. The Plan Commission also has the authority to invite the public to comment on the assessment during a scheduled public hearing. 

Box 5.5 City of Middleton’s Environmental Assessment Checklist. (Does not include Cultural/Geological Preservation, Transportation, Population components of the assessment). 

1. Land Resources                                        YES              NO 

Does the project site involve: 
A. Changes in relief and drainage patterns. Attach a topographic map showing, at a minimum, two (2) foot contour intervals. 
B. A landform or topographic feature of local or regional interest 
C. A floodplain (If yes, attach two (2) copies of a typical stream valley cross-section showing the channel of the stream, the 100 year floodplain limits and the floodway limits (if officially adopted), of each side of the channel and a cross-section of area to be developed) 
D. An area of soil instability — greater than 18% slope and/or organic soils, peaks, or mucks at or near the surface 
E. An area of bedrock within 6 ft. of the soil surface 
F. An area with the groundwater table within 10 ft. of the soil surface 
G. An area with fractured bedrock within 10 ft. of the soil surface 
H. Prevention of gravel extraction 
I. A drainage way for 5 or more acres of land 
J. Lot coverage of more than 50% impermeable surfaces 
K. Prime agricultural land 
L. Wetlands and marshes 
M. Land Elevation above 950 (USGS Datum) 
N. Mapped environmental corridors 

II. Water Resources 

Does the proposed project involve: 
A. Location within an area traversed by a navigable stream or dry run 
B. Greater that 10% change in the capacity of storm-water facility or flow of a waterway within 1 mile. 
C. The use of septic tank-soil absorption fields for on-site waste disposal 
D. Lowering of water table by pumping or drainage 
E. Raising of water table by altered drainage patterns 
F. Lake frontage 

III. Biological Resources 

Does the project site involve: 
A. Critical habitat for plants and animals of community interest 
B. Endangered, unusual or rare species of: 
     1. Land animals 
     2. Birds 
     3. Plants 
C. Removal of over 25% of the present trees

Federal, State and Local Environmental Regulations 

Environmental regulations and standards implemented at the Federal, State and local levels will significantly influence the nature and substance of the environmental impact assessment. In effect, environmental regulations and standards often provide the framework for the environmental assessment requirements outlined in subdivision ordinances such as those discussed above. However, because subdivision ordinances do not always provide explicit reference to the environmental regulations with which proposed developments must comply, it is important to understand the range of possible regulations that may apply to a development project. Box 5.6 lists many of the environmental regulations which may apply to a proposed development. For a list of local regulations, which may implement more stringent compliance standards than Federal and State law, contact the Land Use Council or Board.   

Box 5.6 List of Federal and State Environmental Laws, Statutes and Regulations 

Agricultural Land (Wisconsin Statute, Chapters 91, 92) Agricultural land protection: Ag 91,92 Soil Erosion: Ag 92 

Air Quality (Clean Air Act; Wisconsin Statute, Chapter 285; NR 400–499) 

Endangered Species (Endangered Species Act; NR 27) 

Hazardous Waste Management (Toxic Substances Control Act, Resource Conservation and Recovery Act, Comprehensive Environmental Response and Liability Act (Superfund); Wisconsin Statute, Chapter 291; NR 600–690) Underground storage tanks: NR 630 

Highway and Street Standards (Wisconsin Statute, Chapters 80–90) 

Solid Waste Management (Solid Waste Disposal Act; Wisconsin Statute, Chapters 287, 289; NR 500–590) Waste Reduction: NR 538–555 

Water Quality (Clean Water Act; Wisconsin Statute, Chapter 280,281)

Drinking water supply protection: NR 809. 
Groundwater protection: +Ch. 160; NR 140, 160 
Floodplain management: NR 116 
Sewage Treatment: NR 210 
Septic System sanitary codes: NR 210 
Shoreland protection: NR 115 
Soil erosion: Ch. 281; Ag 92 
Storm-water Discharges/Runoff: NR 216 
Surface Water: NR 102–106 
Wetland Protection: NR 103, 107 

Local Guidelines, including Master Plans, Long-Range Plans, Comprehensive Plans 

To ensure that a proposed development is consistent with a community’s long-range, master or comprehensive plan, the environmental impact assessment should include an analysis of whether the proposed development either meets or does not conform to the goals set forth in the community’s plan. In communities where a long-range or similar plan has been developed, the local subdivision ordinance typically specifies that the proposed development be consistent with the community’s plan. For example, in Burnett County, Wisconsin, a long-range plan was recently developed to address growth management concerns in the County. The plan, which is being implemented throughout the County, provides County officials and the public with a guide for reviewing subdivision plats, certified survey maps, and other land use proposals. While the land use requirements set forth by the Burnett County Zoning Administration do not specifically mandate that an environmental assessment be prepared for each proposed development, the goals of the long-range land use plan are specific and are to be used as a guide in approving proposed developments. For more information on Burnett County’s approach in addressing growth management issues, visit the website at

Phase 4:  Assessing the Extent and Significance of Environmental Impacts Resulting From the Proposed Development 

Information about the proposed development needs to be reviewed in a systematic way. Assessing some basic environmental considerations that are easily quantified is a good place to begin—for example, the wetland acreage that could be lost at the proposed development site. Worksheet 5.1 provides a general framework for recording the level of impact anticipated from the development. The Wisconsin Department of Commerce has developed a Developer/Planning Checklist for assessing possible environmental impacts associated with a proposed development. The checklist is included at the end of this chapter. 

Depending on the characteristics of the proposed development, as identified during completion of Phase 2 of the environmental impact assessment, quantifying some impacts may have more relevance than others. Of particular concern in already developed communities (i.e., suburban and urban areas), are the environmental impacts associated with increased imperviousness of surface areas. Built or paved surfaces prevent infiltration of water into soil, thereby increasing storm-water runoff and the amount of pollutants transported to receiving waters. The result may be degraded water quality and wildlife/aquatic habitat. 

Estimating increases in urban runoff provides a useful measure of potential environmental damage resulting from an individual project and may also be used to estimate the cumulative impacts of development. While addressing polluted runoff seems to demand extensive technical information on such complex matters as pollutant levels, hydrologic models, and the complex specifications of pollution control technologies, recent innovations have made it easier for local communities to estimate potential environmental impacts based on such estimations. It is possible to estimate increased runoff using standardized methods such as the Rational Method which relies on average constants (see Gupta, Ram S. 1989. Hydrology and Hydraulic Systems. Prospect Height, IL: Waveland Press, Inc.); however, increases in storm-water runoff are highly dependent on local conditions and the characteristics of the proposed development. The preferred approach for estimating runoff is one that factors in local conditions. Researchers at the University of Connecticut have developed a tool for local communities to use in understanding the links between land use and water quality. The Nonpoint Education for Municipal Officials (NEMO) project uses geographic information systems to conduct build-out analyses which integrate existing levels of impervious cover with future projections of development. The analysis allows community members to visualize options for future development in terms of impervious cover and by inference, impacts on land and water resources. See the side bar on this page for contact information. Local officials may also find it useful to consult with a local engineer who has prior experience estimating runoff for future developments or designing pollution control/storm-water management technologies. In addition, communities should contact the DNR for more information regarding the developers obligations to manage storm-water runoff. The DNR website also provides a link to the Center for Watershed Protection, an organization which provides assistance to local communities in addressing urban watershed issues. (410) 461–8323; website:

For more information on NEMO... 

Chester Arnold or Jim Gibbons University of Connecticut Cooperative Extension System (860) 345–4511. Mr. Arnold may also be contacted through email at 

Phase 5:  Evaluating Cumulative Environmental Impacts 

Understanding the cumulative effects of development is an important component of community planning and long term environmental protection. As reported by the Council on Environmental Quality, evidence is increasing that the most significant environmental effects may result not from the direct effects of a particular action, but from the combination of individual effects of multiple actions over time. For example, while the development of a subdivision on the urban periphery may not on its own pose a significant threat to a community’s environment, the development of additional subdivisions over time may seriously impact the community’s land, water, and air resources. Conversion of acre after acre of prime farmland for roads, houses and businesses, increased demand for drinking water, impacts on water and air quality, and loss of critical habitat for biological resources are all examples of the cumulative effects of development. 

  • Geographic Information System Analysis assesses the spatial relationship between activities and potential environmental effects and may be used to explore development alternatives. 
  • Questionnaires, interviews, and panels to gather information about the range of proposed developments and natural resources potentially impacted by development. 
  • Checklists are useful for identifying potential cumulative effects by providing a list of common or likely effects and actions which may cause the effects. 
  • Matrices can be used to quantify the interactions between human activities and resources of concern. 
  • Networks and System Diagrams provide a method for identifying the cause-effect relationships which result in cumulative effects. 
  • Modeling is another method for quantifying cause-effect relationships which result in cumulative effects. 
  • Trends Analysis assesses the status of a resource or community over time and changes in the occurrence or intensity of stressors over the same time period. It can also be used to establish acceptable environmental baselines and/or estimate future cumulative effects.

There are various methods for analyzing cumulative effects, some of which are most effective when used with other methods. The methods outlined here are discussed more thoroughly in the Council on Environmental Quality’s guide to considering cumulative effects, referenced at the end of the chapter. While the method selected for evaluating cumulative impacts may vary depending on the availability of resources, the scope and goal of the evaluation should remain consistent. 

One method for assessing potential cumulative impacts of development that continues to gain popularity among communities faced with development challenges is the use of a geographic information system (GIS). In general, GIS is a powerful tool for carrying out spatial analysis of cumulative environmental change. The capability of GIS in layering different types of data (e.g., land use, water resources, infrastructure) and providing a graphic display of alternative development scenarios makes it an excellent planning tool for communities to use. As referred to in earlier sections of this chapter, the State of Wisconsin has invested considerable resources in compiling compatible data layers for all 72 counties in Wisconsin and continues to support local efforts to use the data in a variety of capacities, including comprehensive planning and natural resources management efforts. These functions significantly  increase the ability of communities to consider and evaluate potential cumulative impacts of development. However, current limitations do exist in the number of available, skilled personnel who can perform analytical functions such as cumulative impact assessment. 

Checklists can be a useful tool for identifying and documenting the cumulative impacts that are associated with a particular development. They can be helpful in focusing the discussion of those conducting the assessment on the key cumulative impacts and for documenting how the impacts were selected for future technical analyses. Once a checklist is adapted to the needs of the community, it can be used as a consistent and valid tool for addressing the anticipated cumulative impacts of future projects. Box 5.8 provides a sample checklist used by the General Services Administration (GSA) during the agency’s preparation of Environmental Impact Statements as required under the National Environmental Policy Act. Local communities may find it useful and necessary to adapt standardized questionnaires such as the one used by GSA to their specific needs by adding or deleting questions, or modifying the specific focus of existing questions. It is important to keep in mind that checklists are only intended to identify potential impacts. As such, they should be used in conjunction with other methods that are designed to quantify cumulative impacts, evaluate the costs and benefits of alternatives, and to develop appropriate mitigation measures. 

Box 5.8 Cumulative Impact Assessment Checklist Example 


Impacts are defined by these indicators: Cumulative (C), Direct (D), Indirect (I), Positive (+), Negative (-), or any combination of these indicators. Provide comments/contacts for each as attachment. 

                                                                  NONE             MINOR               MAJOR

1. Subsurface Conditions (soils, groundwater) 
2. Hydrology (drainage, storm-water, water quality, supply) 
3. Landforms (topography, floodplains, related water quality) 
4. Wildlife and Vegetation (vegetation, endangered species, parklands, conservation areas, ecologically critical areas) 
5. Land Use (existing zoning, land use, proposed community long-range plans, productive farmland or timberland 
6. Natural Hazards (seismic, other) 
7. Cultural Resources (historic concerns, architecturally sensitive archaeologically sensitive) 
8. Utilities/services (energy, solid waste disposal, water supply, sewer system and drainage) 
9. Transportation (public transit system, traffic circulation, parking) 
10. Hazardous Materials (underground storage tanks, site contamination, storage of hazardous substances, other) 
11. Other (ambient air, ambient noise, controversy) 


Continual reference to the community’s comprehensive plan as developments are proposed is one simple method for ensuring that growth in the community does not become unmanageable. A community with a long-range plan and comprehensive environmental inventory is well-equipped to anticipate and avoid the potential effects of development on the community’s environment over the long-term. 

Various other methods for assessing the cumulative impacts of development exist and may be appropriate for a community environmental impact assessment. The President’s Council on Environmental Quality (CEQ) has assembled a comprehensive guidance document for considering cumulative effects under the National Environ-mental Policy Act (NEPA). While the guide is written specifically for Federal agencies, it does offer a useful information about how to conduct a cumulative effects assessment, the types of information that should be collected and how to evaluate a pro-posed development in the context of such effects. 


While the task of conducting an environmental impact assessment may seem daunting at first, it is important to recognize the importance of assessing the environmental impacts associated with community development. To do otherwise will likely result in an even greater challenge (and cost) of addressing adverse impacts in years to come. 

Moreover, tremendous gains have been made by Wisconsin communities, state government, and the universities in collecting and managing information about the State’s natural resources. The process of conducting an environmental impact assessment is no longer as resource-intensive or time consuming, especially where baseline data about the current quality and use of natural resources have already been com-piled. For communities that have not collected the relevant information for an environmental impact assessment, but are facing development pressure, now is the time to begin thinking about the long-term sustainability of the community. How does  environmental protection fit into the future of the community? It may not be a paramount goal for community members, but must be balanced with other economic and social goals if the community’s quality of life is to be preserved. Citizen participation and input is an important part of the process; however, a professional environmental consultant or engineer may offer necessary technical sup-port and analysis of the environmental impacts of a proposed development. It is up to the community that hires the consultant to provide direction to the investigation and review results with community values in mind, in order to ensure that the community can pursue its own vision for a quality life. 


Canter, L.W. and Kamath, J. 1995. Questionnaire for cumulative impacts. Environmental Impact Assessment Review 15(4): 311–339. 

Clark, R. 1994. Cumulative effects assessment: a tool for sustainable development. Impact Assessment 12(3): 319–332. 

Council on Environmental Quality, Executive Office of the President. 1997. Considering Cumulative Effects Under the National Environmental Policy Act. Washington, D.C. 

Davies, K. 1992. Addressing Cumulative Effects under the Canadian Environmental Assessment Act: A Reference Guide. Quebec: Canadian Environmental Assessment Agency. 

Holling, C. S., editor. 1978. Adaptive Environmental Assessment and Management (Vol. 3 in International Series on Applied Systems Analysis). John Wiley & Sons. 

Smit, B. and H. Spalding. Methods for Cumulative Effects Assessment. Environmental Impact Assessment Rev 1995; 15:81–106. Elsevier Science Inc.: New York. 

Wisconsin Department of Commerce Developer/Planning Checklist


Does the project meet with all of the local approvals, conditions, and zoning requirements? 

  1. What is the current zoning of the property? Any zoning changes (conditional use permit) needed for the project to move forward? 
  2. Does the project meet fire and police protection standards? What changes are needed to bring the project into conformity? 
  3. Does the project meet with local wetland, shoreline, erosion control, and buffer requirements? 
  4. How will the project or facility fit into the local community’s effective solid waste recycling program? 
  5. If wastewater is discharged to the local municipal treatment plant, can the community accept and handle the flow and treat the effluent? 
  6. Any health and safety risks associated with the project? 
  7. What types and levels of noise would be created by or associated with the project on a short-term or long-term basis? (e.g., traffic, construction, operations) 
  8. What type of light or glare will the proposed project produce? When will the light have the greatest impact? 
  9. What impact will the project have on the surrounding neighbors? Describe the types or kinds of existing facilities within a 1 /2 mile radius of the project. 
  10. What impact will the project have on local streets and roads in the area? Describe any changes in traffic patterns, increased traffic to the area, traffic noises, etc. 
  11. Does the project need new roads, rail, airport services, and other infrastructure improvements such a storm drains, retention ponds, water supply and storage? Can the local community handle all of these special needs of the project? 
  12. What designated or informal recreational opportunities are in the immediate vicinity? Would the project displace any existing recreational uses? 


Does the project meet with the federal and state environmental regulations? What is the likelihood that these permits can be obtained without significant objections from the local residents and environmental groups? 


  1. What types of emissions to the air would result from the proposal (e.g., industry source, dust, automobile, odors, smoke) during construction and when the project is completed? If any emissions, describe and given approximate quantities. 
  2. If the project needs an air permit and is located in a “nonattainment” region of Wisconsin, does the project have the necessary air credits needed to off-set the source’s air emissions? 
  3. Does the source emit more than ten tons of toxic air pollutants? If so, does the project meet Maximum Achievable Control Technology (MACE)? 


  1. Is there any surface water on or in the immediate vicinity of the site (including year-round and seasonal streams, lakes ponds, and wetlands)? 
  2. Are there any irrigation or drainage ditches on or near the site? 
  3. Will the project require any work over, in, or adjacent to (within 200 feet) of the described waters? 
  4. Will any work be needed to fill or dredge materials placed in or removed from surface water or wetland? 
  5. Will the proposed project require surface water withdrawals or water diversions? 
  6. Does the project lie within a 100-year flood plain? 
  7. Does the project involve any discharges of wastewater to surface waters or to the ground? If so, does it meet the pretreatment requirements of the state and pretreatment requirements of the local municipality if the discharge is going to the municipal treatment plant? 
  8. Is the project over five acres in size or fall within the Standard Industrial Classification in the areas of transportation, plastics manufacturing, metal coatings, food processing, or lumber? 
  9. Could any waste materials enter ground or surface waters associated with the site? 
  10. If the location is near one of the four wild and scenic rivers in Wisconsin, has the National Park Service commented upon the project? 


  1. Are there any environmental health hazards, including exposure to toxic chemicals, risk of fire and explosion, spill or hazardous waste that could occur as a result of this project? 
  2. Does [will] this project process solid or hazardous waste? 
  3. Does [will] this proposal transport solid or hazardous materials? Have the proper licenses been applied for and approved? 
  4. Does [will] this site have storage tanks, underground or above ground? If so, what will be stored in the tanks? 
  5. Is the site located on or near a landfill? 


  1. What kinds of vegetation are found on the site? 
  2. What kinds of vegetation will be removed from the site? 
  3. Was the Wisconsin Natural Heritage Inventory Program contacted as to possible sightings or habitats on the site that may contain state and federal endangered species? 
  4. Is the site part of a migration route? 
  5. Does the project need state and federal opinion (U.S. Fish and Wildlife) or approval regarding impact to wildlife and endangered species? 


  1. Are there any places or objects listed on, or proposed for national, state, or local preservation registers known to be on or next to the site? 
  2. Did the State Historical Preservation Officer (SHPO) identify any historic buildings or archaeological sites which would be affected by the project? 
  3. If historic buildings and archeological sites are present on the proposed development site, was documentation obtained from the SHPO as to their eligibility for the National Register of Historic Places? 
  4. If the SHPO agreed that the project would have an adverse effect, was there documentation of the Section 106 consultation process with the Advisory Council on Historic Preservation? 


  1. Is the project located in the state’s nonattainment region in terms of air quality standards? If so, will the project employ more than 100 workers? 
  2. Will the project require new roads, highways, and special access points to get to the site? 
  3. What impact will any new roads and highways have on the vicinity of the project? 
  4. Will the project use water, rail or air transportation? 


  1. Does the project involve conversion of existing farm land? If so, was the Department of Agriculture’s (USDA) Preservation Program contacted? 
  2. Does the project contain “prime, unique, or important” farmland as designated by the USDA? 
  3. If the land is located on any of the above classifications of farmland, did the USDA review the project?