IDOT BICYCLE MAPS Focus on Transportation., Safety and Tourism By WILLIAM T. SUNLEY, Engineer of Local Roads and Streets Credits to: Craig Williams, Bicycle & Pedestrian Program Manager

The Illinois Department of Transportation is producing a series of bicycle maps for each of its nine IDOT districts. The first map of the series, Illinois Official Bicycle Map, Shawnee Region, Map 9, is now available for distribution. The map contains a wealth of information for bicyclists, whether they live close by or are venturing into the area for a first visit.

The maps contain locations and descriptions of more than 50 of the area's more scenic or historic attractions, such as the Shawnee National Forest and the Giant City State Park. It also indicates major annual events in the region, such as the Great Cardboard Boat Regatta each May in Carbondale. The map indicates hiking trails, bicycle rules and safety tips, important phone number for bicycling organizations, transportation and conservation agencies, historic sites, tourism offices and even weather conditions. Even small (but important) details, such as where to find food and lodging are indicated with symbols next to the towns.

More importantly, for virtually all paved roads in the region, the maps show each road's suitability for bicycling, in a green (most suitable), yellow (caution advised) and red (not recommended) format. The map cautions that these ratings "are offered for adult cyclists of average or better experience and who are comfortable sharing the road with vehicular traffic." Even though ratings are not provided for all roads, they are shown on the map in a gray color and on the legend as "Use at your own discretion." These roads, because of their low traffic volumes, are often very suitable for cycling (especially for bikes with wider tires) but the condition of the pavement varies with the seasons. Municipal roads, because of the scale of the map, are limited to those providing connections through the community.

How and why were these maps produced? Several years ago, the Department was challenged with producing a bicycle map to promote safe cycling on the roadways of the state. After researching the available options, the Department chose to provide a product that would best facilitate the use of the bicycle as a transportation option. Bicyclists could then select the safest routes available for travel-to-whatever destination. It was particularly important to develop a system that would provide consistent information on roadway conditions across the state. Further, the Department wanted a product that could be easily updated and revised internally.

The mapping methodology took advantage of an on-going project in IDOT's Office of Planning and Programming to tie the Illinois Roadway Information System (IRIS) database to a computer digitized county mapping system. Certain bicycle-related factors, such as traffic volumes, roadway widths, paved shoulders and pavement condition were extracted from the highway database and used to generate a 'suitability' rating for each roadway segment. This rating was translated to a color display on the digitized county maps.

The expertise of the Cartography Lab at Northern Illinois University was enlisted to transform the working copies of the digitized county maps into final maps for public distribution. To ensure that future revisions can be made with ease, NIU uses computer-technology to create the maps, which simplifies the task of adding roads or changing road ratings several years from now.

To ensure accuracy and consistency, the maps were drawn over scanned images of IDOT's county maps. In order to provide a reasonable amount of detail and a suitable map size, a scale of approximately 1"=31/2 miles was chosen. This scale dictated the series of nine maps for the state, each of which coincides with the IDOT district boundaries. The maps are anticipated to be completed according to the following schedule:

District(s)                       Completion Date
Southern IL                      September 1994
Western IL (4 maps)          December '94 to April '95
Eastern IL (4 maps)           June '95 to December '95

The maps are distributed free-of-charge by IDOT's Map Sales office and by the state's tourism office. Write to:

January 1995 / Illinois Municipal Review / Page 9