June 13, 2007June 13, 2007

Access Access Management Management ProgramProgram

NHCRP Report 420 - Impacts of Access Management Techniques

Source: NHCRP Report 420, TRB 1999

Composite Crash Rate Indices

1 1.3 1.7 2.12.8

4.1

0

1

2

3

4

5

10 20 30 40 50 60

Access Points per Mile

Cra

sh R

ate

Inde

x

Schedule

Design Team ResponsibilitiesDesign Team Responsibilities

• Create a consensus regarding design elements for the access management program.

• Ensure that Districts have input

• Provide recommendations to the State Engineer

-3-

The Roadway Design Guide and other ADOT guides and policies are not regulatory

RDG Permit Rules• Internal Policy• No prescribed legal

standards• ADOT Staff• ADOT consultants• No 3rd Parties, No

appeals• ADOT final say• Not enforceable

• Arizona Administrative Code

• Meets prescribed legal standards

• 3rd Parties (public)• The weight of Law• Subject to legal

review• Enforceable• May be appealed

RDG - Permit Rule

• Roadway design Guidance (mostly)

• Relies on Professional Engineering judgment

• No enforcement needed

• Entirely ADOT discretion.

• Little judgment• Little flexibility• Clear, concise• Enforceable• Applies only to

access decisions

What are the legal issues to ensure design What are the legal issues to ensure design

strength and permit enforcement ?strength and permit enforcement ?

• Access permitting regulates property rights• Permit requirements must be regulatory• Only by weight of law can ADOT have

enforcement powers• ADOT must meet established legal standards

for Rule format, language, clarity.• Rule must be understandable to those whom

do business with ADOT (the public)

Access Classification System

• Sets the system hierarchy

• The access classification determines the answer to the questions:

- May I have access to the state highway? - Where should the access be located? - What type of access may I have? - What are the major design elements?

Access Category

Assignment Status

Arizona State Highway(Draft) Access Management Categories

FW (freeway)

MR (major regional)

RA (rural principal)UA (urban principal)

RB (rural secondary)UB (urban mixed)

UC (urban secondary)

SF (service and frontage roads)

Access Category Design Issues

• Standards for granting or denying access requests.

• Spacing of intersections & signals.

• Volume warrants for turn lanes

Suggested turn volume warrants for turn laneSuggested turn volume warrants for turn lane

Rule Level Access Design Elements

• If the request qualifies for highway access, what will ADOT require?

• Which design elements must be in Regulation to provide enforcement “teeth”

• Which permit elements are expensive

• What can be left in the various ADOT ‘internal’ policies and guides?

Rule Level Access Design Elements

• Access Spacing (location)

• Sight distance requirements

• Turn Lane design (decel, Accel & storage lengths)

• Driveway Geometrics

• Medians (type, when open)

• Legal Enforcement of design permit terms and condition

Rule Level Access Design ElementsRule Level Access Design Elements

• Selection of the Design Vehicle

• Drainage (retention, MS4, system design)

• Cattle guards, gates & location

• Emergency access only.

• Earthwork (side slopes, specs, erosion)

• Design Variances• Exception and Waiver Procedures