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93 state. The initiative promotes environmental stewardship Assessing what can be accomplished within the existing by maximizing the use of existing facilities to the extent framework possible, and fosters economic prosperity through the quick Establishing agreement on recommendations and imple- and efficient movement of people and goods. The initiative mentation approach offers NCDOT, partnering agencies, and other stakeholders Improving stakeholder understanding about access an opportunity to consider a long-term vision when making management land use decisions, as well as design and operational deci- sions on the highway system. As part of the study, INDOT's Statewide Mobility Cor- ridor hierarchy, shown in Figure 54, was used to develop an Implementation of the SHC initiative focuses on six areas: (1) ACS for all state highways in Indiana. Education, (2) Long-Range Planning, (3) Project Planning and Design, (4) Land Use, (5) Corridor Protection, and (6) Drive- As part of this effort, ACS from numerous state DOTs way Permits and Traffic Signals. Access management and the were examined within the context of the INDOT Statewide purchase of access rights are identified as key strategies under Mobility Corridor hierarchy. An initial ACS was drafted Corridor Protection. In addition, under Driveway Permits and and subsequently refined through several reviews by a Study Traffic Signals, alternative solutions to traffic signals and drive- Advisory Committee composed of key staff from INDOT's way consolidation and sharing are highly encouraged. central and district offices, as well as representatives from FHWA and various Indiana MPOs and counties. As part of the SHC initiative, four Facility Types--Free- ways, Expressways, Boulevards, and Thoroughfares--and Table 20 provides an overview of INDOT's ACS. The ACS associated Control of Access Definitions were developed uses INDOT's Statewide Mobility Corridor hierarchy as the to create a set of understandable and consistent definitions primary basis for a tiered system of access categories. (Because for all roadways for NCDOT and its partners to use in the interstate highways and freeways are of the highest level of planning, design, and operations processes. The defini- importance and are fully access controlled, they represent the tions are based primarily on the function of the roadway, highest category within the ACS. Spacing criteria for these level of mobility and access, and whether the facility has roadways are established in other sources such as the INDOT traffic signals, driveways, or medians. These definitions Roadway Design Manual and AASHTO's "Green Book.") were developed from a committee composed of members from FHWA and NCDOT's Traffic Engineering, Highway Tiers 1 and 2 of the ACS include all "Statewide Mobil- Design, Project Development, and Transportation Plan- ity Corridors" and "Regional Corridors," respectively, on ning branches. Table 19 shows a comparison of NCDOT the INDOT highway system. Tier 3 of the ACS includes all facility types. "Local Access Corridors" on the INDOT highway system. Because these "Local Access Corridors" serve a mobility function and accommodate some through-traffic volume, Development Of Access Classification System the term "Sub-Regional Corridors" has been used for Tier 3 For Indiana Department Of Transportation roadways in the INDOT ACS. In 2004, the Indiana Department of Transportation (INDOT) In the classification system, Statewide Mobility Corridors initiated the Indiana Statewide Access Management Pro- (Tier 1), Regional Corridors (Tier 2), and Sub-Regional Cor- gram (81) to develop and begin implementing an access ridors (Tier 3) are each subdivided into two subcategories management strategy to support INDOT's Long-Range (Type A and Type B) that reflect distinct variations within Transportation Plan and implementation of its Statewide each of these Tiers. For all three tiers, the Type A distinc- Mobility Corridor Concept. The study involved a review of tion applies exclusively to multilane roadways, and the Type INDOT's existing access management process to identify its B distinction applies exclusively to two-lane roadways. The limitations, as well as opportunities for its refinement. The purpose for this distinction was to reflect the unique charac- following key project issues were addressed in the study: teristics associated with two-lane roadways, which constitute approximately 76% of Indiana's state highway network. Crafting a pragmatic approach to access management that fit Indiana's conditions A summary of the key differences in the signalized intersec- Reflecting the diversity of transportation conditions in tion spacing guidelines for the three tiers is shown in Table 21. Indiana Addressing Indiana's institutional and policy As shown in Table 21, the ideal spacing guideline for sig- environment nalized intersections on all tiers of the state highway system is Explaining the benefits of access management 0.5 mi in most cases. The 0.5 mi spacing typically accommo- enhancements dates progression speeds ranging between 30 mph and 60 mph, Drawing creatively from lessons learned in other states depending on the length of the signal cycle that is selected. For

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94 TABLE 19 NORTH CAROLINA DOT FACILITY TYPES COMPARISON CHART Freeways Expressways Boulevards Thoroughfares Functional Purpose High Mobility, Low High Mobility, Low to Moderate Mobility, Low to Moderate to Low Mobil- Access Moderate Access Moderate Access ity, High Access AASHTO Design Interstate or Arterial Arterial or Collector Collector or local Classification Freeway Posted Speed Limit 55 mph or greater 45 mph to 60 mph 30 mph to 55 mph 25 mph to 55 mph Control of Access Full Limited or Partial Limited or Partial None Traffic Signals Not Allowed Not Allowed Allowed Allowed Limited Control of Access - Limited Control of Access - Not Allowed Not Allowed Partial Control of Access - Partial Control of Access-one One Driveway Connection Driveway Connection per Allowed with Full Move- per Parcel; Consolidate and/ Parcels Consolidate and/or ments; Consolidate or Driveways Not Allowed or Share Driveways and Share Driveways and Limit Share Connections, if Limit Access to Connecting Access to Connecting Streets possible Streets or Service Roads, or Service Roads; Restrict to Restrict to Right-in/ Right-in/Right-out Right-out Minimum 2 Lanes; No Minimum 4 Lanes Minimum 4 Lanes with Minimum 2 Lanes with Median; Includes Facili- Cross-Section with Median Median Median ties with Two Way Left Turn Lane Provided only at inter- At-Grade Intersections for changes for Major Cross Provided only at inter- most Major and Minor Cross Streets and At-Grade Inter- changes; All Cross Streets (Occasional Inter- Primarily At-Grade Connections sections for Minor Cross Streets are Grade- change at Major Crossing); Intersections Streets; Use of Acceleration Separated Use of Acceleration and and Deceleration Lanes for Decelerations Lanes At-Grade Allowed; Alternatives to All-Movement Crossovers Allowed; Minimum Spacing Public-use Crossovers Encouraged; Minimum between All-Movement Not Allowed; U-turn Spacing between All Move- Crossovers is 2000 feet Median Openings for Median Crossovers ment Crossovers is 2000 feet (posted speed limit of Not Applicable Use by Authorized (posted speed limit of greater greater than 45 mph) or Vehicles only when than 45 mph) or 1200 feet 1200 feet (posted speed limit Need is Justified (posted speed limit of 45 of 45 mph or less) mph or less) Source: Facility Type & Control of Access Definitions (80, p. 8). state highways with posted speeds of 40 mph or less that are The spacing guidelines for unsignalized intersections located in built-up urban areas, a 0.25 mi spacing guideline and driveways are based on AASHTO stopping sight dis- applies. The 0.25 mi spacing typically accommodates progres- tances, and are a function of speed, irrespective of tier. The sion speeds ranging between 15 mph and 30 mph, depending decision-making process with respect to the application of on the length of the signal cycle that is selected. the access spacing guidelines may consider existing and projected future traffic volumes and the type of environment In cases in which the signal spacing guidelines cannot (built-up, intermediate, suburban, and rural areas). In gen- be met, a deviation may be allowed, provided a minimum eral, greater flexibility is needed for lower speed roadways acceptable bandwidth criterion can be met. This minimum in built-up areas. acceptable bandwidth criterion varies depending on the tier of the state highway system and the location of the highway in either an urban or rural area.

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95 TABLE 20 OVERVIEW OF INDOT ACCESS CLASSIFICATION SYSTEM Level of Importance/ Access Category Type Traffic Function Design Standards Accommodates high-speed, high-volume, and long- Multi-lane roadways with full access-control. distance through traffic for interstate, intrastate, or Access via interchanges only (no direct private intercity travel. Also can provide a major connec- access to abutting properties allowed). All road- Interstate Highways tion between suburban areas and metropolitan ways are multi-lane and median-controlled/divided. and Freeways centers. At-grade intersections and access driveways not permitted under any circumstances. Interchange spacing is in accordance with the INDOT Roadway Design Manual. Provides connections to major metropolitan areas Includes all multi-lane roadways. Access generally within the State and to neighboring states. Provides occurs only at interchanges or at-grade public street accessibility to cities and regions around the state. intersections. Some movements at public street inter- Accommodates high-speed and long-distance trips. sections may need to be restricted based on existing A Can accommodate heavy commercial vehicle traf- and projected operating conditions and intersection fic. Includes most rural non-Interstate routes on the spacing. Private access to abutting properties is not Principal Arterial System. allowed, unless property has no reasonable alterna- tive access (via joint-use driveways or frontage Tier 1: Statewide roads) or opportunity to obtain such access. Mobility Corridor Includes only 2-lane roadways. Access generally only occurs via at-grade public street intersections. Some movements at public street intersections may Same traffic function as Tier 1, Type A. Generally need to be restricted based on existing and projected B provides key rural connections between metropoli- operating conditions and intersection spacing. Private tan areas. access to abutting properties is not allowed, unless property has no reasonable alternative access (via joint-use driveways or frontage roads) or opportunity to obtain such access. Includes all multi-lane roadways. Generally median- Provides connections to smaller cities and regions, controlled/divided. Public street connections occur at- feeds traffic to the Statewide Mobility Corridors, grade. Private access to abutting properties is allowed. and provides for regional accessibility. Accommo- Full movements and signalization are allowed for pub- A dates moderate to high-speed traffic, medium dis- lic street connections and "commercial major" drive- tance trips, and moderate volumes of through traffic ways only. All other private driveways are limited to and commercial vehicle traffic. Can accommodate unsignalized, right-in/right-out (median-controlled) local heavy traffic volumes. access, with left-turns allowed conditionally subject to INDOT review and approval. Tier 2: Regional Corridors Includes only 2-lane roadways. Public street connec- tions occur at-grade. Private access to abutting proper- ties is allowed. Full movements are allowed at all pri- vate driveways, with the exception of access driveways located within 300 feet of an existing (or B Same traffic function as Tier 2, Type A. potential future) signalized intersection which must be right-in/right-out (with left-turn access allowed condi- tionally subject to INDOT review and approval). Sig- nalization is allowed for public street intersections and "commercial major" driveways only. Includes all multi-lane roadways. Public street con- Typically provides access to local residences and nections occur at-grade and may be signalized. businesses in rural areas and small towns. Accom- A "Commercial major" driveways may also be signal- modates moderate to low speed traffic, short dis- ized. Full movements are allowed at public street tance trips, and moderate local traffic volumes. Tier 3: Subregional intersections and all private access driveways. Corridors Includes only 2-lane roadways. Public street connec- tions occur at-grade and may be signalized. "Com- B Same traffic function as Tier 3, Type A. mercial major" driveways may also be signalized. Full movements are allowed at public street intersec- tions and all private access driveways. Source: Access Management Guide (83, Table 3-1, p. 29).