EXISTING PRACTICE-LOCATION OF INTERCHANGES AND GRADE SEPARATIONS IN THE STATE OF ILLINOIS

THE EXISTING PRACTICE IS DESCRIBED OF LOCATING HIGHWAY- HIGHWAY GRADE SEPARATIONS AND INTERCHANGES ON FREEWAYS, EXPRESSWAYS AND PRIMARY STATE HIGHWAYS WITHIN THE STATE OF ILLINOIS. THE FOLLOWING FACTORS ARE CONSIDERED IN THE LOCATION OF GRADE SEPARATIONS AND INTERCHANGES: (1) NATIONAL DEFENSE, (2) ECONOMIC ACTIVITY, (3) EMPLOYMENT, (4) RECREATION, (5) FIRE PROTECTION, (6) ESTHETICS, (7) SAFETY, (8) EDUCATION AND DISRUPTION OF SCHOOL DISTRICT OPERATIONS, (9) ENGINEERING, ROW, AND CONSTRUCTION COSTS FOR HIGHWAY FACILITIES AND RELATED TRANSPORTATION FACILITIES, (10) MAINTENANCE OF HIGHWAY FACILITIES AND OTHER TRANSPORTATION FACILITIES, (11) OPERATION OF HIGHWAY FACILITIES AND OTHER TRANSPORTATION FACILITIES DURING CONSTRUCTION AND FOLLOWING COMPLETION, (12) RESIDENTIAL CHARACTERISTICS AND LOCATION, (13) RELIGIOUS INSTITUTIONS AND PRACTICES, (14) RIGHTS AND FREEDOM OF INDIVIDUALS, (15) FINANCING OF GOVERNMENT, (16) CONSERVATION, AND (17) PROPERTY VALUES. FLOW DIAGRAMS ARE PRESENTED TO ILLUSTRATE THE GENERAL PROCEDURES PRACTICED. TABLES SUMMARIZE THE TREATMENT OF RURAL INTERSECTIONS FOR VARIOUS COMBINATIONS OF INTERSECTING ROADS IN ILLINOIS. THE PRACTICE OF LOCATING HIGHWAY-HIGHWAY GRADE SEPARATIONS AND INTERCHANGES DEPENDS UPON THE TYPE OF AREA TRAVERSED BY THE INTERSTATE ROUTE. SOME OF THE SPECIFIC PROCEDURES USED AT THE DISTRICT LEVEL IN ILLINOIS ARE SUMMARIZED. A BENEFIT COST ANALYSIS IS USUALLY CONDUCTED AND SUPPLEMENTED BY COMPUTING THE RATE OF RETURN ON CAPITAL INVESTMENT OR TOTAL ANNUAL TRANSPORTATION COST. CHANGES IN CONSTRUCTION AND USER COSTS THAT OCCUR WHEN A GRADE SEPARATION STRUCTURE IS UPGRADED TO AN INTERCHANGE THROUGH THE PROVISION OF INTERCHANGE RAMPS ARE CONSIDERED IN THE ECONOMIC ANALYSIS.

  • Supplemental Notes:
    • 45 Pp, 12 FIG, 12 TAB, 2 APP
  • Corporate Authors:

    Northwestern University, Evanston

    Department of Civil Engineering, 600 Foster Street
    Evanston, IL  USA  60208
  • Authors:
    • Wegmann, F J
    • Walker, C R
    • Satterly, G T
  • Publication Date: 1967-1

Subject/Index Terms

Filing Info

  • Accession Number: 00203436
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Mar 16 1970 12:00AM