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Access Management Principles Introduction and Overview. Efficient traffic throughput. Right to property access. Neil Spiller FHWA, Washington, D.C. Presentation. – General overview – Benefits and Consequences – Access Management in Practice – Elements of an AM Program. Part 1.

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slide1

Access Management Principles

Introduction and Overview

Efficient traffic throughput

Right to property access

Neil Spiller

FHWA, Washington, D.C.

presentation
Presentation

– General overview

– Benefits and Consequences

– Access Management in Practice

– Elements of an AM Program

Introduction to Access Management Principles

part 1
Part 1

Overview

Introduction to Access Management Principles

what is managing access
What is “Managing Access”?

Managing and Planning the Spacing and Design of:

Driveways

Median Openings

Traffic Signals

Interchanges

Introduction to Access Management Principles

definition of am
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

purpose of am balance mobility vs access
Purpose of AM:Balance Mobility vs. Access

Freeways

Major Arterials

Minor Arterials

Major Collectors

Minor Collectors

Local Streets

Introduction to Access Management Principles

a very brief history of am part 1 of 4
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

a very brief history of am part 2 of 4
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

a very brief history of am part 3 of 4
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

basic right to access
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

a very brief history of am part 4 of 4
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

colorado 1979
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

national perspective
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

part 2
Part 2

Benefits and Consequences

Introduction to Access Management Principles

slide15

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

benefits of am
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

groups who benefit
Groups Who Benefit

Which groups will benefit from good AM?

  • Motorists
  • Cyclists
  • Peds
  • Business Owners
  • Communities

Introduction to Access Management Principles

of driveway crashes by movement
% 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

composite crash rate indices
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

am in the transportation and land use cycle

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

over arching goal of am
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

conflicts cont d
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

conflict points
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

conflicts
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

consequences of poor am
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

effect of speed differential to propensity for crashes
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

how to improve consequences
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

part 3
Part 3

Access Management in Practice

Introduction to Access Management Principles

slide29

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

driveway bypass lane
Driveway Bypass Lane

Where restricted from placing a median, can you install a bypass lane?

Introduction to Access Management Principles

median redesign
Median Redesign

Note:

1) increased separation between intersections

2) Introduction of U-turns to replace former movements

Introduction to Access Management Principles

slide32

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

slide33

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

signal spacing variables
Signal Spacing Variables
  • “Tweak” these . . .
    • Intersection spacing
    • Overall cycle lengths
    • Cycle phasing
  • To “Seek” these . . .
    • Progression speed
    • Progression efficiency

Introduction to Access Management Principles

relationship between cycle length signal spacing and speed
Relationship between cycle length, signal spacing, and speed

Introduction to Access Management Principles

what methods are used
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

who is responsible for am
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

what is functional intersection area and why is this important
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

functional intersection area
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

application of access window
Application of ‘Access Window’

Window for left or right

Window for RT only

No window on higher street

Introduction to Access Management Principles

different types of access controls
Different types of Access Controls
  • “Police” power
  • Eminent domain
  • Condemnation
  • Statutes and statutory designation

Introduction to Access Management Principles

in plain english
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

part 4
Part 4

Elements of an AM Program

Introduction to Access Management Principles

elements of an am program
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

slide45

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

have a plan stick to it
Have a plan – stick to it!

“uncontrolled” access over time

“controlled” access via permitting

Introduction to Access Management Principles

levels of approval
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

traffic impact study areas
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

fhwa s role
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

fhwa does not
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

federal aid highway system routes eligible for federal aid
Federal Aid Highway System(Routes eligible for Federal aid)
  • Interstate System
    • Dwight D. Eisenhower National System of Interstate Highways
    • Routes of highest importance
    • Shall not exceed 43,000 mi.
  • National Highway System
    • Shall not exceed 178,250 mi.
    • All routes on the Interstate System are part of NHS
    • Includes STRAHNET routes

Introduction to Access Management Principles

fhwa functional classification guidelines
FHWA Functional Classification Guidelines

Principal arterials

Minor arterial streets (“roads” in rural areas)

Collector streets (“roads” in rural areas)

Local Streets (“roads” in rural areas)

For Rural, Urban, or Small Urban designations

Introduction to Access Management Principles

trb s website www accessmanagement info
TRB’s websitewww.accessmanagement.info

Complete proceedings and prior years’ too!

Ten principles of AM -- animation

Introduction to Access Management Principles

slide54

Managed

Access

= Success !

Introduction to Access Management Principles

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