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Access Management Principles Introduction and Overview

Access Management Principles Introduction and Overview

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Access Management Principles Introduction and Overview

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  1. Access Management Principles Introduction and Overview Efficient traffic throughput Right to property access Neil Spiller FHWA, Washington, D.C.

  2. Presentation – General overview – Benefits and Consequences – Access Management in Practice – Elements of an AM Program Introduction to Access Management Principles

  3. Part 1 Overview Introduction to Access Management Principles

  4. What is “Managing Access”? Managing and Planning the Spacing and Design of: Driveways Median Openings Traffic Signals Interchanges Introduction to Access Management Principles

  5. Definition of AM FORMAL: Access management is the programmatic control of the location, spacing, design, and operation of driveways, median openings, interchanges, and street connections to a roadway. (TRB Manual) INFORMAL: Where the road meets the driveways Introduction to Access Management Principles

  6. Purpose of AM:Balance Mobility vs. Access Freeways Major Arterials Minor Arterials Major Collectors Minor Collectors Local Streets Introduction to Access Management Principles

  7. A Very Brief History of AM part 1 of 4 New Jersey 1902 – established “speedways” for horses and bicycles. “No public streets or other highways shall cross or intersect the speedway at grade without consent of the county” U.S. Supreme Court 1906 – decided that access control along highways was a sovereign power of the states. Introduction to Access Management Principles

  8. A Very Brief History of AM part 2 of 4 Between 1900 and 1920 the number of automobiles grew from 8K to 10M and lobby groups emerged (e.g., AAA and AASHO) 1919- DDE undertook a transcontinental military convey from D.C. to San Francisco (62 days) 1921 Federal-Aid act established a system of national routes Introduction to Access Management Principles

  9. A Very Brief History of AM part 3 of 4 In 1920’s it became apparent that automobile (related) deaths were soaring. In 1937 NY and RI established the first statewide statutes that included “abutting” access control and required permits and reviews as part of their state route adoption plan By late 1940’s almost every state legislated permitting accesses to some degree and court decisions began to confirm that public safety and mobility essentially trumped a landowner’s absolute right to access at any point Introduction to Access Management Principles

  10. Basic “right to access” A property owner has right to have access (i.e., not to be landlocked) but does NOT have right to expect absolute access at any point, NOR should they expect compensation for relocated access as long as the government shows justifiable cause and least-impact. Introduction to Access Management Principles

  11. A Very Brief History of AM part 4 of 4 National standards for individual driveway design were developed in 1960 – AASHO “An Informational Guide for Preparing Private Driveway Regulations for Major Highways” NCHRP Report 121 (1971) “Protection of Highway Utility” stands as one of the earliest, most recognized discussions of access control Beginning of modern AM – credited to Colorado, 1979, when they created 1st comprehensive principals of AM and spelled out the safety, aesthetic and delay-reducing benefits of AM “incorporated” into statute Introduction to Access Management Principles

  12. Colorado, 1979 “The lack of adequate access management on the highway system and the proliferation of driveways and other access approaches is a major contributor to highway accidents and the greatest single factor behind the functional deterioration of highways in this state. As new accesses are constructed and signals erected, the speeds and capacity of the roadways decrease, and congestion challenges to the motorist increase.” -- Colorado State Highway Access Code Introduction to Access Management Principles

  13. National Perspective • “The lack of access control along arterial highways has been the largest single factor contributing to the obsolescence of highway facilities” NCHRP Report 121 Protection of Highway Utility • “Every study since the 1940’s has indicated a direct and significant link between access frequency and accidents” International R/W Assoc. conference paper, 1999 Introduction to Access Management Principles

  14. Part 2 Benefits and Consequences Introduction to Access Management Principles

  15. Driveways are inevitable and necessary but as their numbers go up, so too does the propensity for accidents in that corridor. Introduction to Access Management Principles

  16. Benefits of AM • Preserve integrity of the roadway system • Improve safety and capacity • Extend functional life of the roadways • Preserve public investment in infrastructure • Preserve private investment in properties • Provide a more efficient (and predictable) motorist experience • Improve “thru” times through a corridor • Improve aesthetics(less pavement, more green) Introduction to Access Management Principles

  17. Groups Who Benefit Which groups will benefit from good AM? • Motorists • Cyclists • Peds • Business Owners • Communities Introduction to Access Management Principles

  18. % of Driveway Crashes by Movement 16% Here’s a scoop! The majority of access-related crashes involve LT’s (63%) 27% 10% 47% Introduction to Access Management Principles

  19. Composite Crash Rate Indices Crash rate indices increase as # of access points per mile increases 5 4.1 4 2.8 3 Crash Index: Ratio of crashes to Access Points per Mile 2.1 1.7 2 1.3 1 1 0 10 20 30 40 50 60 # Access Points per Mile Introduction to Access Management Principles

  20. AM applied here through physical means AM in the Transportation and Land Use Cycle AM applied here through administrative means Introduction to Access Management Principles

  21. Over-arching Goal of AM: What’s the bottom line? Limit the number and impact of driver decision and conflict points from impacting on through traffic. Introduction to Access Management Principles

  22. Conflicts, cont’d Traffic Conflict Think of a single traffic conflict as one rock in a pond. The ripples are easy to see and are predictable. However, when dozens of rocks are thrown in at once, the ripples are dynamic, they create chaos, and it is difficult to avoid one at the cost of another. Introduction to Access Management Principles

  23. Conflict Points Each access point creates potential conflicts between through traffic and turning traffic. Cross Diverge Merge Stop / Queue Weave Introduction to Access Management Principles

  24. Conflicts • 16 Crossing • 8 Diverge • 8 Merge 32 TOTAL • 1 Crossing • 3 Diverge • 4 Merge 8 TOTAL (and don’t forget pedestrian and bicycle movements too!) Introduction to Access Management Principles

  25. Consequences of Poor AM • Increase in crashes and crash rates • Poor capacity throughput • Increased delays • Reduced roadway efficiency • Potential for unsightly strip development • Decreased property values • Potential for unwanted cut-thru traffic • Potential for less desirable experience, hence, less customers will want to make the trip Introduction to Access Management Principles

  26. Effect of Speed Differential to Propensity for Crashes 100 90x 80 60 Relative Crash Ratio 40 23x 20 3.3x Baseline 0 10 +10 MPH +20 MPH +25 MPH (20) (30) (35) Speed Differential (MPH) Introduction to Access Management Principles

  27. How to improve “Consequences” • Unclutter the corridor (“Pruning”) • Direct where driveways are best suited • “Assign” turn movements by defining and separating them • Develop guidelines for property access, thru traffic, and hierarchy of streets • Enforce against violations and poor practices in siting driveways and streets Introduction to Access Management Principles

  28. Part 3 Access Management in Practice Introduction to Access Management Principles

  29. Use non-traversable medians to separate traffic and direct motorists where to access properties.Use turn lanes to queue separate movements and to “free up” through movements Introduction to Access Management Principles

  30. Driveway Bypass Lane Where restricted from placing a median, can you install a bypass lane? Introduction to Access Management Principles

  31. Median Redesign Note: 1) increased separation between intersections 2) Introduction of U-turns to replace former movements Introduction to Access Management Principles

  32. Results—Fewer accidents on ‘Managed’ roads “Regular” Arterials 14 12.9 Highly Access Managed Arterials 12.9 12 12.5 10 10.5 Accidents Per Million Miles Traveled Source: "Colorado Access Control Demonstration Project" - 1985 8 7.2 6 5.0 4 3.5 2 0 Colfax Ave AlamedaAve Federal Blvd Wadsworth Ave Havana Ave Parker Dr Arapahoe Ave Introduction to Access Management Principles Access Management

  33. Results—Higher ‘thru’ speeds on ‘Managed’ roads (mph) Speed Effects of Access Management on travel speeds in the P.M.peak hour "Regular”Arterials 23 Colfax 28 Alameda 25 Federal 25 Wadsworth 30 Havana Highly Accessed-Managed Arterials Parker 48 46 Arapahoe 0 10 20 30 40 50 Introduction to Access Management Principles Access Management

  34. Signal Spacing Variables • “Tweak” these . . . • Intersection spacing • Overall cycle lengths • Cycle phasing • To “Seek” these . . . • Progression speed • Progression efficiency Introduction to Access Management Principles

  35. Relationship between cycle length, signal spacing, and speed Introduction to Access Management Principles

  36. What methods are used? • Permits, legislation and corridor planning • Medians • Auxiliary lanes • Signals and signal spacing • Driveway location, spacing, and design • Corner clearance • Cross-access and joint access • Frontage roads and connectors Introduction to Access Management Principles

  37. Who is Responsible for AM? Professionals that guide urban development • Planners • Engineers • Architects • Approval agents (Boards, Councils, etc.) • Developers • Land use attorneys • Agency staff Non professionals • Citizens, motorists • Property Owners • Ad-hoc groups (pedestrians, bicycles, social change) Introduction to Access Management Principles

  38. What is “Functional Intersection Area”and why is this important? The influence area associated with a driveway includes • The impact length (distance back at which cars begin to be affected) • Perception-reaction distance • And the “car length” Upstream length > Downstream length Introduction to Access Management Principles

  39. Functional Intersection Area The upstream and downstream areas of influence that affect driver decision. Note that closely spaced driveways and intersections have overlapping areas. • Elements that impact the functional intersection area: • stopping sight distance; RT-out acceleration; slowing to turn; perception-reaction time; queue storage; etc., are there more? Introduction to Access Management Principles

  40. Application of ‘Access Window’ Window for left or right Window for RT only No window on higher street Introduction to Access Management Principles

  41. Different types of Access Controls • “Police” power • Eminent domain • Condemnation • Statutes and statutory designation Introduction to Access Management Principles

  42. In plain English?! An agency uses eminent domain to purchase or “take” the right of access. An agency uses their police power to approve or deny the application for a driveway and impart public safety Introduction to Access Management Principles

  43. Part 4 Elements of an AM Program Introduction to Access Management Principles

  44. Elements of an AM Program • Have administrative rules, ordinances or guidelines • Educate your boards, councils, and public • Establish an approval authority • Have geometric design standards • Provide staff training and education re: policies • Monitor approvals (inspect) and conduct agency evaluations • Develop an request/approval process and fees, etc. • Provide consistent and justifiable application of standards • Document meetings, contacts, and written communications • Allow for appeals and justified deviations/exceptions Introduction to Access Management Principles

  45. Every stakeholder needs to be “on board” with the plan and aware of the consequences of, and need for, guidance, structure and goal Introduction to Access Management Principles

  46. Have a plan – stick to it! “uncontrolled” access over time “controlled” access via permitting Introduction to Access Management Principles

  47. Levels of Approval • Federal interstates / State highways • Local highways and streets • Local site plan approvals must meet other agencies’ regulations (zoning, R/W, EPA) • Adopted Master Plans • Zoning and long range planning must be considered • Other stakeholders? Adjacent/abutting property owners? Public? Introduction to Access Management Principles

  48. Traffic Impact Study Areas Scope: Driveway only or nearest intersection Closest intersections up- and down stream Radius of neighborhood intersections Large cordon of intersections, including major connections Very small site or re-use Owner-transfer, same use-upgrade or isolated (i.e., non urban) location Small site, local impact Bank, restaurant, gas station Medium site, destination oriented Small strip retail, small office or residential complex Large site, regionally impacting Shopping center, large residential/retail complex, big-box store Introduction to Access Management Principles

  49. FHWA’s Role • To champion the role that AM serves in improving safety and reducing delay • Increase awareness of, and benefits of . . • To sponsor AM-related studies and enable academic research • To educate (through NHI courses, et al) Key Products AMDVD “Benefits of Access Management” Tri-fold Public Meeting Handout and CD AM Resource DVD CD Introduction to Access Management Principles

  50. FHWA does not . . . • Write AM guidelines for states, et al • Mandate AM regulations (although we certainly “advise” ) as a general rule • Make decisions on new access’ on interstates (the states do) Caveat – because FHWA oversees Federal funding, we have a mandated role in reviewing, recommending, and approving some state-sponsored activities regarding (mostly) the interstates Introduction to Access Management Principles