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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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Access management principles introduction and overview

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


Access management principles introduction and overview

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 go up, so too does the propensity for accidents in that corridor.

  • 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 go up, so too does the propensity for accidents in that corridor.

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 go up, so too does the propensity for accidents in that corridor.

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 go up, so too does the propensity for accidents in that corridor.

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 go up, so too does the propensity for accidents in that corridor.

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: go up, so too does the propensity for accidents in that corridor.

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 go up, so too does the propensity for accidents in that corridor.

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 go up, so too does the propensity for accidents in that corridor.

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 go up, so too does the propensity for accidents in that corridor.

  • 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 go up, so too does the propensity for accidents in that corridor.

  • 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 go up, so too does the propensity for accidents in that corridor.

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” go up, so too does the propensity for accidents in that corridor.

  • 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 go up, so too does the propensity for accidents in that corridor.

Access Management in Practice

Introduction to Access Management Principles


Access management principles introduction and overview

Use go up, so too does the propensity for accidents in that corridor.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 go up, so too does the propensity for accidents in that corridor.

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

Introduction to Access Management Principles


Median redesign
Median Redesign go up, so too does the propensity for accidents in that corridor.

Note:

1) increased separation between intersections

2) Introduction of U-turns to replace former movements

Introduction to Access Management Principles


Access management principles introduction and overview

Results— go up, so too does the propensity for accidents in that corridor.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


Access management principles introduction and overview

Results— go up, so too does the propensity for accidents in that corridor.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 go up, so too does the propensity for accidents in that corridor.

  • “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 go up, so too does the propensity for accidents in that corridor.

Introduction to Access Management Principles


What methods are used
What methods are used? go up, so too does the propensity for accidents in that corridor.

  • 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? go up, so too does the propensity for accidents in that corridor.

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 go up, so too does the propensity for accidents in that corridor.“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 go up, so too does the propensity for accidents in that corridor.

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’ go up, so too does the propensity for accidents in that corridor.

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 go up, so too does the propensity for accidents in that corridor.

  • “Police” power

  • Eminent domain

  • Condemnation

  • Statutes and statutory designation

Introduction to Access Management Principles


In plain english
In plain English?! go up, so too does the propensity for accidents in that corridor.

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 go up, so too does the propensity for accidents in that corridor.

Elements of an AM Program

Introduction to Access Management Principles


Elements of an am program
Elements of an AM Program go up, so too does the propensity for accidents in that corridor.

  • 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


Access management principles introduction and overview

Every go up, so too does the propensity for accidents in that corridor. 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! go up, so too does the propensity for accidents in that corridor.

“uncontrolled” access over time

“controlled” access via permitting

Introduction to Access Management Principles


Levels of approval
Levels of Approval go up, so too does the propensity for accidents in that corridor.

  • 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 go up, so too does the propensity for accidents in that corridor.

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 go up, so too does the propensity for accidents in that corridor.

  • 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 . . . go up, so too does the propensity for accidents in that corridor.

  • 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 go up, so too does the propensity for accidents in that corridor.(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 go up, so too does the propensity for accidents in that corridor.

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 website go up, so too does the propensity for accidents in that corridor.www.accessmanagement.info

Complete proceedings and prior years’ too!

Ten principles of AM -- animation

Introduction to Access Management Principles


Access management principles introduction and overview

Managed go up, so too does the propensity for accidents in that corridor.

Access

= Success !

Introduction to Access Management Principles