Dearborn County Transportation Assessment Complete ... - OKI

urban boundary will need to be updated. While there is not an urban boundary currentlyin the county, there are roadways which have a curb and gutter configuration; mostly inincorporated areas of the county. To account for these roadways we have included anUrban Local category.2.2 RURAL ROADWAY CLASSIFICATIONSIn the past, Dearborn County has categorized roadways into four (4) classifications;freeway, arterial, collector, sub-collector/local. These classifications were basedprimarily on the connectivity of the facility and the degree of access that is provided. Ingeneral, the freeway category included I-74 and I-275, the arterials were identified asU.S. or State routes, collectors provided links between local roadways and arterials andthe remaining facilities were classified as sub-collectors/local streets. Upon furtherinvestigation, it was determined that a more detailed classification system was neededfor the county. A system that is not only based on connections provided but also on theadditional criteria listed earlier in this section.The INDOT Design Manual provides for several additional classifications based not onlyon connectivity but also the amount of traffic that a roadway serves. These additionalcategories will provide Dearborn County a more detailed picture of the roadway system.The new procedure to classify roadway will follow a two phase process.1) Classification by Access - A determination will be made as to theinterconnectivity of the roadway and the importance of the route not onlywithin the county but externally as well. This analysis will establish theroadway category; arterial, collector or local roadway.2) Classification by Traffic Volumes - After the roadway category isdetermined, an analysis of the Average Daily Traffic (ADT) will subclassifythe facility and determine the design parameters appropriate tothat level of roadway.Each roadway classification utilized is accompanied by appropriate design criteria andtypical sections. These classifications along with the guidelines are detailed in thischapter.Arterial SystemThere are two types of arterials, the principal arterial and the rural arterial. A principalarterial is generally identified as a facility which serves corridor movements adequate forstatewide or interstate travel. The roadways in this category can be identified as theinterstate system within the county. As these routes are maintained by the state, theywill not be discussed in the Assessment; rather the effort is focused on the roadwaysmanaged by the county, the rural arterial system.Rural arterials are categorized by their linkages to cities or larger towns and theygenerally provide interstate or intercounty service. They are capable of attracting travelover long distances and have a spacing that is consistent with the population density inthe county. All developed areas are generally within a reasonable distance to a ruralarterial.Dearborn County Transportation Assessment Page 2-2