Arterial Street Access Control Study
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CAPITAL AREA REGIONAL TRANSPORTATION STUDY (CARTS)
TECHNICAL COMMITTEE
Governmental Unit or Agency Delegate
Clinton County - Road Commission Robert Ancel, Supervisor/Manager
-Board of Commissioners Richard Hawks, Commissioner
Eaton County-Road Commission Dean DeLaMater, Engineer/Manager
-Planning Department Dennis Dunnigan, Director
Ingham County-Road Commission William Burchfield, Supt./Manager
-Board of Commissioners Aubrey Marron, Commissioner
East Lansing-Planning Department Robert Owen, Planning Administrator
-Engineering Department Gordon Melvin, Engineer
Lansing-Grants Coordinator Vivian Preston, Coordinator
-Planning Department James Spackman, Deputy Director
-Planning Department Kunwar Rajendra, Transportation Coord.
-Public Service Dept. Howard McCaffery, Director
-Public Service Dept. Raymond Severy, Traffic Engineer
Delhi Charter Township Elizabeth Augenstein, Treasurer
Delta Charter Township Mark Graham, Planning Director
DeWitt Charter Township Alta Reed, Supervisor
Lansing Charter Township Frank Sudac, Supervisor
Meridian Charter Township Joseph Harris, Development Director
Capital Region Airport Authority Daniel Otto, Technical Aide
Capital Area Transportation Authority Richard Leonard, Planning Manager
Michigan Dept. of Natural Resources
- Air Quality Division Mary Ann Corl, Engineer
Michigan Dept. of Transportation
- Bureau of Transportation Planning Richard Nellett, Regional Coordinator
David Babcock, Project Analyst
- District Office (Jackson) Larry Suboski, Traffic Engineer
Michigan State University
- Campus Parks and Planning Thomas Kehler, Director
Tri-County Regional Planning Commission
(ex-officio) Leo Bagley, Chief Planner
Federal Aviation Administration
(ex-officio)
- Airports District Office Vacant
Federal Highway Administration
(ex-officio)
- Division Office - Region V James Patten, Area Engineer
Urban Mass Transportation Admin.
(ex-officio)
- Regional Office Michael Higginson, Regional Rep.
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TABLE OF CONTENTS
Page
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Problem Statement. . . . . . . . . . . . . . . . . . . . . . . . . 1
Need for Access Control. . . . . . . . . . . . . . . . . . . . . . 5
Safety. . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Arterial Street Functional Integrity. . . . . . . . . . . . . 8
Energy Consumption and Air Pollution. . . . . . . . . . . . . 9
Access Control Techniques. . . . . . . . . . . . . . . . . . . . .11
Driveway Design Considerations. . . . . . . . . . . . . . . .11
Driveway Spacing. . . . . . . . . . . . . . . . . . . . . . .21
Corner Clearance. . . . . . . . . . . . . . . . . . . . . . .21
Arterial Design Considerations . . . . . . . . . . . . . . . . . .23
Frontage Roads. . . . . . . . . . . . . . . . . . . . . . . .23
Access on Collector Streets . . . . . . . . . . . . . . . . .24
Combined Access . . . . . . . . . . . . . . . . . . . . . . .25
Continuous Left Turn Lanes. . . . . . . . . . . . . . . . . .27
Intersection Spacing. . . . . . . . . . . . . . . . . . . . .28
Median Treatments . . . . . . . . . . . . . . . . . . . . . .29
Site Design Considerations. . . . . . . . . . . . . . . . . .31
Design Concept Integration. . . . . . . . . . . . . . . . . .33
Control Technique Selection. . . . . . . . . . . . . . . . . . . .35
Typical Criteria Considered . . . . . . . . . . . . . . . . .35
Integration of Land Use and Transportation Planning . . . . .37
Implementation Considerations. . . . . . . . . . . . . . . . . . .39
Comprehensive Plans . . . . . . . . . . . . . . . . . . . . .40
Zoning Ordinances . . . . . . . . . . . . . . . . . . . . . .40
Site Plan Review. . . . . . . . . . . . . . . . . . . . . . .41
Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
Appendices . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
Appendix A . . . . . . . . . . . . . . . . . . . . . . . . .45
Appendix B . . . . . . . . . . . . . . . . . . . . . . . . .49
Appendix C . . . . . . . . . . . . . . . . . . . . . . . . .57
Appendix D . . . . . . . . . . . . . . . . . . . . . . . . .61
List of References . . . . . . . . . . . . . . . . . . . . . . . .85
ii
LIST OF FIGURES
Page
FIGURE 1. Roadway Function by Classification. . . . . . . . . 2
FIGURE 2. Street Functions. . . . . . . . . . . . . . . . . . 2
FIGURE 3. Basic Driveway Design . . . . . . . . . . . . . . .12
FIGURE 4. Effects of Driveway Design on
"Swept Path" of Vehicles. . . . . . . . . . . . . .13
FIGURE 5. Examples of Substandard Driveways . . . . . . . . .14
FIGURE 6. Examples of Adequate Driveways. . . . . . . . . . .14
FIGURE 7. Options for One-Way Operations. . . . . . . . . . .15
FIGURE 8. Supplemental Driveway Design Features . . . . . . .16
FIGURE 9. Options for Two-Way Driveways . . . . . . . . . . .17
FIGURE 10. Use of Channelizing Islands . . . . . . . . . . . .18
FIGURE 11. Channelizing Island/Efficient Site Design . . . . .18
FIGURE 12. Right Turn Deceleration Lane. . . . . . . . . . . .19
FIGURE 13. Prohibition of Left-Turn Egress . . . . . . . . . .19
FIGURE 14. Separation of Ingress & Egress Functions. . . . . .20
FIGURE 15. Prohibition of Right Turn Egress. . . . . . . . . .20
FIGURE 16. Traffic Queue Blocking Drive. . . . . . . . . . . .21
FIGURE 17. Driveway Adjacent to Intersection . . . . . . . . .22
FIGURE 18. Traffic Conflicts Resulting from
Intersection too close to Intersection. . . . . . .22
FIGURE 19. Examples of Frontage Roads. . . . . . . . . . . . .23
FIGURE 20. Access on Collector Street. . . . . . . . . . . . .24
FIGURE 21. Example of Combined Access. . . . . . . . . . . . .25
FIGURE 22. Photos of Combined Access . . . . . . . . . . . . .26
FIGURE 23. Examples of Left Turn Lanes . . . . . . . . . . . .27
FIGURE 24. Intersection Spacing. . . . . . . . . . . . . . . .28
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LIST OF FIGURES
(continued)
Page
FIGURE 25. Channelizing Median . . . . . . . . . . . . . . . .29
FIGURE 26. Median Controlling Left Turns . . . . . . . . .29
FIGURE 27. Median Controlling Left Turns . . . . . . . . . .30
FIGURE 28. Parking/Driveway Conflicts . . . . . . . . . . . .31
FIGURE 29. Unique Parking Conflicts . . . . . . . . . . . .32
FIGURE 30. Drive-in Window/Site Circulation . . . . . . . . .32
FIGURE 31. Integration of Design Concepts . . . . . . . . .33
FIGURE 32. Allocation of Turning Movements . . . . . . . . .36
FIGURE 33. Parking and Access Regulation Program . . . . . .63
FIGURE 34. Partially Developed Area . . . . . . . . . . . .65
FIGURE 35. Comprehensive Plan . . . . . . . . . . . . . . .67
FIGURE 36. Access Management Plan . . . . . . . . . . . . .69
FIGURE 37. 5 Years After Plan Approval . . . . . . . . . . . .71
FIGURE 38. 15 Years After Plan Approval. . . . . . . . . . . .73
FIGURE 39. Existing Situation. . . . . . . . . . . . . . . . .75
FIGURE 40. Access Management Plan. . . . . . . . . . . . . . .77
FIGURE 41. Comprehensive Plan. . . . . . . . . . . . . . . . .79
FIGURE 42. 5 Years After Plan Approval . . . . . . . . . . . .81
FIGURE 43. 15 Years After Plan Approval. . . . . . . . . . . .83
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EXECUTIVE SUMMARY
This report deals with the complex problems of arterial street
access control and the problems encountered in forming policies and
regulations for controlling direct access driveways along arterial
streets. Included in the discussion is a brief overview of
traditional land use and transportation planning policies which
have created the phenomenon of "strip" commercial development and
associated traffic problems. Examples of such traffic problems
include accident experience, traffic delay, increased fuel
consumption and auto emissions, all of which result from conflicts
between "through" traffic and traffic entering and exiting from
direct access driveways. The text includes discussion and graphics
depicting examples of poorly designed arterial corridors, and
direct access driveways as well as examples of possible remedial
treatments for correcting design deficiencies. Examples of such
treatments include proper driveway design, site design, frontage
roads, combined access driveways, and traffic channelization
techniques. Also included are implementation considerations which
deal with zoning and planning concerns and the development of
access control regulations and permit processes.
This document was produced as a response to local concerns, notably
Delta Charter Township, over traffic congestion problems and
aesthetics along major roadways. It is intended to identify and
quantify these associated problems and to raise the level of
consciousness to the causes and possible solutions.
INTRODUCTION
INTRODUCTION
The Arterial Street Access Control Study provides an orientation
towards the development of comprehensive policies for controlling
direct access driveways along major streets. The study deals with
techniques to minimize land access/traffic movement conflicts while
attempting to achieve an equitable balance between land service and
traffic service functions of major streets.
The overall goals of access control policies include reducing
accidents, alleviation of traffic congestion, reduction of energy
consumption, preservation of long term integrity of the traffic
movement function, and the promotion of aesthetically pleasing
arterial corridors.
This study provides examples of a variety of techniques available
to help achieve these goals such as driveway design and placement
considerations, arterial street design, and land use policies. It
should be noted that these examples depict a synthesis of design
considerations which have been developed by a variety of
transportation engineers and planners from throughout the country.
They have been portrayed in this document to provide a conceptual
understanding of access control problems. Examples depicted in
this document should not be assumed to be acceptable design
standards in every municipality and on all streets. Each
municipality or agency which has jurisdiction over public travel-
ways generally requires a review and permit process before allowing
the establishment of a direct access driveway on a major street.
Thus, in preparing a site plan, or reviewing a development
proposal, local policies and regulatory standards must be examined
in conjunction with any design standards depicted in this document.
For the purpose of this report an arterial street is considered to
be any major road which carries, or by virtue of location or
continuity, has the potential to carry through traffic as well as
to provide access to adjacent development. Characteristics of
these types of roads include traffic volume of at least 7500
vehicles per day, frequently has four travel lanes or two with left
turn provisions, adjacent land use usually contains considerable
commercial development, many intersections are signalized, and
usually is a mile or one-half mile road.
Problem Statement
The street and highway system has two major functions:
- movement of traffic between dispersed points
- provision of access to individual properties
Because of the disparate characteristics of these two functions no
single roadway type can safely or efficiently meet all travel
needs. Thus, five roadway types are frequently utilized to
describe the movement of vehicles from origin to destination.
Figures 1 and 2 on page 3 illustrate this concept.
1
Ideally the primary function of an arterial street is to provide
relatively uninterrupted, long distance travel service throughout
an urbanized area. While traffic movement is still important land
access functions are better provided by local and collector
streets. However, increasingly the movement function of arterial
and collector streets in the urban environment has been compromised
by land service, or the provision of access to lands abutting the
arterial.
These functions become increasingly incompatible as more and more
commercial, industrial and residential development locates on major
arterials seeking the advantages of high visibility and easy access
to the motoring public. Eventually, both the land access and
traffic service functions of arterial streets are degraded by
congestion resulting from conflicts between turning and maneuvering
vehicles, and through traffic. The carrying capacity and safety of
the travelway suffers from the deleterious effects of high traffic
volumes coupled with unlimited access.
These phenomena which impede the proper functioning of arterial
streets occur gradually, almost naturally and are caused by a large
number of separate decisions in the private and public sectors made
with little comprehensive guidance. This process can be
characterized as having a spiraling effect. Initially, a newly
constructed or improved arterial operates at a relatively high
level of service and provides long distance through traffic service
to large numbers of motorists. Such a situation creates attractive
opportunities for residential and commercial development by virtue
of the arterials ability to provide ease of movement between
distant points, high traffic volumes, and favorable operational
characteristics. As development proliferates along an arterial
traffic increases which in turn attracts more development which
attracts more traffic, and so goes the spiral. This type of
development pattern soon creates
2
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what is commonly referred to as "strip commercial development".
Inherent characteristics of strip development include:
- A business's reliance on single purpose automobile trips
for patronage
- The need for on-site circulation and storage of
automobiles
- The desire for visibility and easy access to the motoring
public
- Each developed parcel functions as a free-standing
traffic generator
These characteristics of strip development create conditions which
severely impair the traffic carrying capacity of an arterial
street, such as:
- Direct traffic conflicts between turning or maneuvering
vehicles entering or leaving a driveway, and "through"
arterial traffic.
- Disparity in vehicle speeds resulting from vehicles
slowing to turn, change lanes, merging and de-merging.
- Advertising signs, buildings, utility poles, and traffic
control signs which eventually clutter a strip
development create distractions and reduce effective
sight distance.
- Maneuvering traffic, frequent stops or speed changes
increase travel time, increase fuel consumption, and
degrade air quality.
- Traffic conflicts caused by disparity in relative vehicle
speed, turning movements, and lane change maneuvers
increase accidents and impair the safety of arterial
streets.
Thus, the end result is an arterial street which operates at much
less than optimum capacity or efficiency because of the cumulative
effects of traffic interference and "marginal friction" resulting
from the conflicting service functions of land access and traffic
movement.
4
NEED FOR ACCESS CONTROL
The following discussion provides a rationale for the provision of
arterial access control by quantifying factors identified in the
previous section. This rationale relates the value of ac-cess
control to the health, safety, and general welfare of the public by
expounding upon the following major points:
1. Safety (accidents, personal injury, property damage)
2. Long term integrity of the arterial function
3. Energy consumption and air pollution
Safety
The relative safety of public thoroughfares is understandably one
of the most important considerations when assessing traffic
operations and related factors such as arterial access. Three
parameters; accidents, personal injury and property damage are
helpful tools in illustrating and diagnosing problems of
conflicting traffic movements and their affect on arterial safety.
The following is a list of results from various accident studies
conducted throughout the country in an attempt to quantify the
effects of unlimited access on arterial street safety:
- Two separate studies conducted by Schoppert1, and Head2
both in Oregon, based on 3 years and 2 years of accident
data respectively, indicate that accident rate predictors
involve the following factors in sequence of importance.
1. Traffic volumes (driveways & streets)
2. Frequency of driveways or intersections
3. Design features such as lane and shoulder width,
sight restriction, curb return radii
4. Relative vehicle speeds
5
- The results of these and two other studies conducted by
Staffield3 and Peterson4 show a strong correlation
between an increase in accidents, an increase in the
number of commercial establishments, and an increase in
the total number of driveways per mile.
- In a two year study, Michaels and Petty5 found that
14.4%, of two vehicle accidents on Indiana County roads
involved driveways.
- Box6 has conducted the most complete study of driveway
accidents by type of maneuver and collision. His studies
in Skokie, Illinois show the following percentage
breakdown on driveway accidents:
Maneuver Turn Collision Driveway Accidents
Entering Left Rear-end 26%
Leaving Left Right-angle 24
Entering Left Head-on angle 15
Entering Right Rear-end 12
Leaving Right Right-angle 7
Leaving Right All other 8
Leaving Left All other 3
Entering Right All other 3
Entering Left All other 2
100%
Box also found that 11.2% of the total accidents in Skokie,
Illinois involved driveways.
The above figures include only accidents that were related to
direct access driveways along arterial streets and do not include
those related to other intersections.
These figures take on greater significance when viewed in light of
the fact that they underestimate the actual number of driveway
related accidents. This is because there are four types of
accidents which are difficult to identify and are under-represented
in driveway related accident statistics.
6
These are:
1. The rear-end accident that happens upstream from the
driveway because of a vehicle slowing down to enter the
driveway;
2. The sideswipe accident caused by vehicles changing lanes
behind a vehicle preparing to enter the driveway;
3. The rear-end accident that happens downstream from the
driveway involving a vehicle from the driveway that has
not yet gained enough speed; and
4. Collisions involving two vehicles using closely spaced
adjacent driveways and collisions of driveway vehicles
with intersection vehicles when the driveway is close to
the intersection.
Property damage and personal injury are obvious results of accident
experience. While it is difficult to correlate these factors
directly to driveway accidents the Michigan State Police MALI
section (Michigan Accident Location Index) has compiled some
information concerning West Saginaw St. which will serve as an
illustration of the problem's magnitude.
On West Saginaw St. from Waverly Rd.to Creyts Rd. during an 18
month period, January 1978 through June 1979, there were a total of
353 accidents resulting in 186 personal injuries and an estimated
$879,300.00 in economic loss. This translates into 20 accidents,
10 personal injuries, and $48,850 loss per month on a two mile
stretch of arterial.
These factors are compounded by the direct public cost of police
involvement in attending accident scenes, and the indirect costs to
society of higher insurance both for automobiles and health care.
Judging from the relatively small scope of this one example, the
problem is probably very significant when considered on a regional
scale. Clearly, any mechanism or technique which could help
alleviate these safety problems is a benefit to the motoring
public.
7
Long Term Integrity of Arterial Street Function
The increasingly severe effects of traffic congestion on the
performance of arterial streets dictates that appropriate action be
taken to preserve their long term carrying capacity. Access
control is of principal importance in ensuring that an arterial,
once constructed and open to traffic, will continue to have high
traffic movement capability. This will simultaneously present
opportunities to implement new practices on miles of arterial
roadways which will provide for reasonable and efficient land
access. A balance between these functions is essential. If left
uncontrolled, the carrying capacity and safety of the roadway can
be degraded to the extent that people will avoid using the roadway,
possibly shift in to residential streets. This defeats not only
the traffic movement function of the arterial but also the exposure
feature which initially made the abutting lands valuable.
It is estimated that under average conditions, the capacity of a
four lane arterial street with a 45 mph speed limit will be reduced
by over one percent for every two percent of the traffic that turns
between the right lane and un-signalized driveways. For example,
if a street carries 1,200 vehicles per hour in a direction and 120
turn into driveways and 120 turn out of driveways per mile (20
percent turns), then the capacity in that direction will be reduced
by 10 percent.
This amount of reduction has the potential to cause the level of
service to deteriorate from the normal design level to a congested
condition. This is especially important when viewed in light of
the fact that over 30 percent of traffic may turn into Driveways
along a fully developed arterial with strip development.
The following quote expresses this relationship between arterial
streets and abutting property.
"Correctly understood, the relationship between roadside land
and highways depends most on the capacity of the highway to
accommodate traffic efficiently and safely. The motorist who
dislikes to use a circuitous route to a roadside business
establishment has shown that he will decrease his patronage
altogether when he is forced to suffer congestion or to risk
unwarranted danger in order to turn from his place in the
stream of traffic into a roadside driveway."
8
Energy Consumption and Air Pollution
As the percent energy situation becomes more serious all facets of
society are searching for ways to use precious fuel supplies more
efficiently. Nowhere are these efforts more important than in the
transportation system. The Federal Highway Administration notes
that each day over 100 million automobiles, 2 million trucks, and
one half million buses use nearly 7 million barrels of gasoline and
diesel fuel. That is about 109 billion gallons per year, or 816
gallons for every registered automobile, truck, and bus. If that
816 gallons were used as efficiently as theoretically possible - on
level surface with no curves, and at a steady 35 mph, the average
car would travel about 20,000 miles/year. Of course vehicles will
not always operate on level ground, and at a steady speed. They
will have to stop and slow down many times each year. The actual
average traveled distance per auto is about 10,000 miles per year
Two factors important to fuel consumption, vehicle speed and
changes in speed, are directly affected by traffic operations over
which control can be exercised. Access control can have a positive
impact on change in speed and indirectly on through traffic vehicle
speeds.
For an automobile travelling at 30 mph, 100 fewer stops each day
results in saving one gallon of gasoline; and 150 fewer speed
changes of 20 mph or more would save another gallon. Also, a recent
FHWA study indicates that fuel consumption increases approximately
11.2 gallons/1000 Stops, and 6.6 gallons/1000 Slow Downs of 20 mph
or more. This study also noted a consumption rate of 650
gallons/1000 Vehicle Idling Hours resulting from travel delay at
stop lights, signs, congested areas, etc.
This same study also reports that carbon monoxide emissions are
increased by 25 lbs/1000 Stops, 19 lbs,/1000 Speed Changes of 20
mph or more, and 2,430 lbs/1000 vehicle idling hours. Hydrocarbons
and nitrogen oxides emissions are also increased by these factors.
For a more complete discussion of these parameters, please
reference, Procedures For Estimating Highway User Costs, Fuel
Consumption, and Air Pollution, U.6. DOT, FHWA, March 1980.
In the Tri-County region thousands of vehicles each day make
thousands of speed changes and stops. By attempting to eliminate
the unnecessary portion of the travel delays, through access
control and other techniques, significant progress can be made in
reducing energy consumption and improving air quality.
9
ACCESS CONTROL TECHNIQUES
Arterial access control techniques entail a wide variety of policy,
regulatory, and physical considerations that can be applied at
different stages of arterial development. Many techniques may
prove valuable for new or developing arterials, but may be
inappropriate for use as a remedial treatment on a fully developed
arterial. For this reason any implementing agency or group of
agencies within a governmental jurisdiction should consider and
employ access control techniques that are flexible enough to
encompass a wide range of access problems on all types of
arterials. The following discussions identify common available
control techniques and examples of their application. It should be
emphasized that these control techniques are provided as examples.
Decisions to implement individual techniques at any level must be
made following careful consideration of local conditions in terms
of both political and social aspects, and of physical and spatial
arrangements of specific arterials. In other words, each site
specific access control problem will require a site specific
solution.
It should also be noted that the following examples deal with major
concepts only. Consideration of all techniques would require
analysis of well over 100 control strategies. For a more complete
discussion of such strategies reference, Technical Guidelines for
the Control of Direct Access to Arterial Highways. J. L. Glennon,
(Washington, D.C., FHWA, August, 1975).
Driveway Design Considerations
The ability of a driveway to accommodate a turning vehicle at a
particular speed within its geometric limits depends upon a
combination of four design factors:
- throat width
- curb return radius
- profile
- angle
Figure 3 depicts these features as they apply to a single two-way
driveway. Since this driveway type is generally the most common
along arterial streets it is important to understand how these
simple design features can improve functional characteristics.
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Curb return radius, or the amount of flare of the curbing
connecting the edge or throat of the driveway with the edge of the
nearest travel land, should be related to the swept path of a
vehicle entering or leaving a particular driveway. Figure 4
shows the path of a passenger car entering driveways of two
different designs. the importance of adequate flare or return
radius becomes readily Apparent. Obviously, in the upper example a
vehicle would occupy a substantial portion of the throat entering
the driveway. This creates potential conflict with exiting
vehicles and can result in slower turning speed, creation of an
obstacle for through traffic behind the entering vehicle, and
increases the chances of an accident experience.
The lower example shows that proper curb return greatly improves
the operations of a driveway with the same throat width by reducing
lane encroachment interference.
Figures 5 and 6 depict examples of drives that incorporate "good"
and "bad" design principles. These photographs clearly indicate
the desirability of proper design features which are intended to
maximize turning speeds, and increase safety. Notice features such
as throat width, grade separation, And curb return.
13
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It must be recognized that while the above concepts are basic to
almost all driveway designs, there are developments which cannot be
serviced effectively with a single two-way drive for these
developments there are a number of design options which are
available to increase the efficiency and safety of ingress and
egress.
In permitting or requiring variations from a basic two way drive,
the local implementing authority should balance the need for
additional property access with the need to preserve the movement
function of the arterial roadway.
Figures 7 through 9 illustrate some of the optional features such
as channelizing islands and deceleration Lanes which can be
combined with the basic driveway designs for both two-way and one-
way operations. Selection of these techniques should be based upon
engineering judgement in conjunction with the trip generation and
turning movement considerations.
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Figures 10 through 15 depict examples of several driveway design
options as they have been applied in various areas in the Tri-
County region. These types of driveway designs, used in
conjunction with proper arterial street design, can greatly
increase the efficiency and safety of the public travelway.
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Driveway Spacing
Techniques available in attempting to adequately space driveways
include land use controls such as zoning, encouragement of joint
access between adjacent developments, closing of unnecessary
driveways, and attempting to provide access to another street.
Whatever method or standard is adopted by a local jurisdiction it
is important to stress the value of maximizing driveway spacing.
Many traffic engineers feel that from a functional standpoint
proper driveway spacing should be in the range of 150- to 200 feet
along major arterial roadways to avoid traffic conflicts and to
leave usable islands for utility poles, traffic control devices,
etc. However, in many if not most instances, such standards can
create hardships for developers because of the resulting large
frontage. A more realistic approach would relate driveway spacing
to adjacent driveways and nearby street intersections in an effort
to optimize spacing in relation to existing local conditions.
Corner Clearance
The maintenance of sufficient corner clearance is perhaps one of
the single most important arterial design concepts. Severe
conflicts can result from traffic queues blocking driveways, and
from vehicles maneuvering from the driveway, which in effect
operates as a "T" intersection, into the "cross" intersection where
potential conflict points are the greatest.
Numerous examples of inadequate corner clearance abound in the Tri-
County region.
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Arterial Design Considerations
Many functional problems along arterial roadways could be minimized
or avoided entirely be incorporating proper design features at the
time of the arterials's construction or upgrading. Examples of
valuable design concepts include:
Frontage Roads
Many times it is assumed that the panacea for all access control
problems is the provision of frontage road service. While it is
true that a properly designed frontage road system can improve the
functional characteristics of an arterial system, it is incorrect
to consider them a cure-all. This concept is but one tool in a
broad and complex system of possible control techniques. Some of
the limiting factors which could determine the feasibility of
implementing frontage road construction are extensive right of way
requirements, cost of construction And right-of-way procurement,
possible disputes over who assumes maintenance responsibility of
the frontage road, and possible operational incompatibility with
existing arterial system.
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23
Encourage Access on Collector Streets
This concept has value although in many areas it may be difficult
to implement because traditional land use And zoning practices have
established a precedent of strip commercial development along the
arterial. Thus, any land which would remain open along the arterial
between collectors would likely encounter heavy development
pressure which can be difficult for local jurisdictions to resist.
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24
Encouraged Combined Access
This concept has been utilized successfully within the Tri-County
region and has great potential for implementation in several
developing areas. The use of shared access can reduce the total
number of driveways along an arterial. This results in fewer
potential conflict points, which can improve functional
characteristics of the arterial and reduce accident experience.
It should be noted that if the concept of shared access is to be
implemented special consideration should be given to driveway
design.
Combining access for two or more traffic generating land uses may
necessitate the use of special driveway design considerations to
accommodate higher traffic volumes.
Click HERE for graphic.
25
Click HERE for graphic.
26
Continuous Left Turn Lanes
The continuous left turn lane is a common technique used to
preserve arterial capacity by removing the obstacle of left turning
vehicles from through traffic lanes. However, it should be noted
that continuous left turn lanes, when used indiscriminately, can
add to arterial congestion by allowing unlimited and uncontrolled
left turn movements and encourage piecemeal land development. The
application of continuous left hand turn lanes is not effective on
existing arterials with evenly distributed, well spaced access
points. On new or heavily travelled arterials a median system which
controls left turning movements are preferable.
Click HERE for graphic.
27
Intersection Spacing
Both "T" intersections and major street or signalized intersections
should be properly spaced to ensure congestion free operation along
arterials.
Click HERE for graphic.
One rule of thumb in spacing "T" intersections is to offset them to
discourage through movement across arterials. A common standard
for placing "T" intersections is 600' to 700'; however, actual
spacing will depend upon local conditions.
Major or signalized intersections should also be adequately spaced.
Many standards have been developed to deal with this design
feature; they most often call for a spacing of 1200 to 1600 feet.
Again the actual spacing must be determined by local conditions.
However, it is important to note that regular spacing of signalized
intersections is essential in the proper design and operation of
capacity preserving progressive signal timing systems along heavily
traveled arterials.
28
Median Treatments to Control Left Turns
These types of control techniques attempt to minimize traffic
conflicts by physically separating certain movements, particularly
left turns. Such methods are valuable in defining maneuvering
paths, prohibition of hazardous movements, and channeling left
turning movements to appropriate access points. These techniques
are generally cost effective where large traffic volumes and many
access points are present.
Click HERE for graphic.
Click HERE for graphic.
29
Click HERE for graphic.
30
Site Design Considerations
It is important when addressing arterial access control problems to
consider the role of individual site design in causing or
preventing traffic conflicts. Some of the most crucial factors to
consider include:
. Internal circulation; can automobiles circulate within
the site without necessitating the use of the arterial?
. Driveway placement in relation to parking areas; will
parking maneuvers block the drive causing traffic to back
up along the arterial?
Click HERE for graphic.
31
Click HERE for graphic.
. Unique features; such as any special problems unique to one
land use or land use type than can cause conflicts such as
drive-in windows or parking areas.
Click HERE for graphic.
. Receiving and shipping; is there adequate space and are there
proper facilities to accommodate space and are there proper
facilities to accommodate vehicles servicing the land use
without affecting internal circulation?
In general, site design considerations encompass common sense
techniques which can help in avoiding serious traffic problems.
32
Design Concept Integration
Figure 31 depicts an example of how many of the aforementioned
driveway and arterial design techniques can be integrated into
overall geometric design and construction. Notice how conflicting
turning movements are controlled by land medians, certain turning
movements have been prohibited or channelized by the use of
driveway islands, and access points (driveways) have been designed
to fit the needs of the and uses occupying their respective
parcels.
Click HERE for graphic.
33
CONTROL TECHNIQUE SELECTION
Methods Used To-Select and Justify Access Control Techniques
Undoubtedly, when a local jurisdiction endeavors to implement
access control provisions, especially those that represent a break
with established practices, technical justification will be requir-
ed. In most instances traffic control measures are selected through
the use of warrants. Warrants are an attempt to quantify minimum
site conditions that should be met to justify implementation of a
technique. Characteristically, warrants attempt to ensure that the
technique will be both operationally effective and cost efficient.
Because of the unique nature of many access control problems pre-
determined warrants may not always be applicable. Thus, access
control measures may have to be selected from site specific data.
Typical Criteria Considered
. Examine Accident Statistics. Does a particular driveway
or site have a particularly high accident rate? Many
times abnormal accident experience can be the first
indicator of an access control problem.
. Estimate Site Trip Generation. It is important to know
the volumes of trips generated by a site during either
the peak hours, whole day, or both. In the case of a
proposed development this can be done by making counts of
turning movements at an existing project with similar
characteristics, and calculating the trip generating
rates in terms of an appropriate unit, i.e. vehicles/1000
ft. of Gross Leasable Floor Area. If a similar
development is not available for study, such data can be
obtained from various studies such as Trip Generation,
published by the Institute of Traffic Engineers which
contains trip generation rates for many types of
development.
. Determine Directional Distribution of Trips. Allocate
trips generated by a development to proposed access
points based on directions of approach and departure, and
assign appropriate volumes to individual access points.
By relating this information to existing roadway traffic
volumes a basis is provided for selecting driveway
designs which may utilize turn prohibitions or traffic
channelization features appropriate for existing
conditions.
. Estimation of Turning Movements. By combining steps one
and two estimates of turning movements can be developed.
These estimates are important tools in determine the
cumulative effect upon arterial capacity of a series of
development proposals.
35
. Evaluate Potential Conflicts with Street Traffic.
Examine conflicts created by ingress and egress turning
movements, particularly left turning movements.
Determine needed design features, i.e., left turn lanes,
arterial medians, etc., and any roadway improvement that
may be needed adjacent to the site. Also, visualize
"downstream" traffic impacts at critical intersections
and adjacent driveways and assess needs for improvement.
A complete and thorough analysis of all these factors will probably
not be possible for all driveway permit proposals. However, in the
case of a major development, or, development which may have
significant impact on the adjacent arterial system, a planner or
engineer can use such data to provide a planning board an appraisal
of the traffic effect of a new development. Such knowledge of
probable traffic problems can be very useful in establishing design
requirements, selection of driveway locations, and application of
particular control techniques. For a much more detailed discussion
of established warrants and cost effectiveness for arterial access
control techniques, reference, Technical Guidelines for the Control
of Direct Access to Arterial Highways, (J.C. Glennon, FHWA, 1975).
Click HERE for graphic.
36
Integration of Land Use and Transportation Planning
The best way to maintain a balance between the movement and
accessibility aspects of the arterial system is to plan, design,
construct, and control the system and adjacent land uses with that
purpose in mind. Highway planning, design and operations
techniques will play a major role in relating the functional
requirements of the arterial street with the accessibility needs of
future land uses planned for the area.
Planning and direct control of land uses abutting arterial streets
must occur in conjunction with proper highway, design and
operations to preserve the movement function of the roadway
network.
It must also be realized that the functional characteristics and
operational conditions of a particular arterial will change over
time. Thus, many times development occurs along travelways before
traffic conditions and the street's significance to the regional
system warrant a major upgrading. In this situation the existing
development, by virtue of its proximity to the street, many times
precludes or hinders adequate right-of-way acquisition if such an
upgrading becomes necessary. This problem can be dealt with by
protecting right-of-way along roads. This can most easily be
accomplished through local zoning powers which should endeavor to
maintain adequate set back from the travelway and also encourage
land uses which would be compatible with traffic conditions
predicted for the upgraded road. This would include light industry
warehousing or land uses that can be easily converted such as large
lot, single family, estate type of housing.
Identification of roads which have potential for becoming major
arterials is available in the Tri-County Regional Long Range Street
and Highway Plan. Generally, these roads fall on section lines or
half-mile lines. Other roads which may have potential are those
that connect rapidly developing areas, or lead to a new traffic
generator such as a shopping center, factory, or highway
interchange.
Appendix D depicts several examples of land use/access control
plans developed by various agencies in other areas. These can
serve to illustrate the necessity of a coordinated approach which
combines land use and transportation planning and the importance of
long term comprehensive guidance when developing a major arterial.
37
IMPLEMENTATION CONSIDERATIONS
At present the access control policies of most jurisdictions are
weak and ineffective. Often policies are not written or are
nonexistent, making implementation of control measures Inconsistent
or impossible. These problems have been compounded by the
relatively short time horizon of local zoning which has allowed
extensive strip development and "unlimited access" along many
arterials. As previously mentioned, this lack of uniform control
has permitted the establishment of undesirable precedents.
The success of a program to refute these precedents will require
the integration of technically sound planning and design principles
with the policy level decision-making process to achieve parity
between land use decisions and long range operational
considerations of arterial streets. Success will also depend upon
the commitment of a community to resist inevitable pressure that
will be brought to bear by developers in support of the status quo.
To achieve this, a community must develop a coherent, applicable,
and equitable comprehensive access control policy which conforms to
established planning an zoning enabling legislation. Such policies
must recognize the "indefeasible right" of abutting property owners
to access. However, it must be noted that the legal obligation
mandates a municipality to provide "reasonable" access, not
"unlimited" access.
Local governments have the authority to manage and influence land
development in the public interest through comprehensive planning,
zoning, subdivision regulation, capital improvements planning, and
similar direct activities. These techniques can define the
arterial street system, determine adjacent land uses, establish the
location of access points, determine internal site design and
circulation, and numerous other specific characteristics.
These considerations must be melded into a systematic review
mechanism which methodically examines existing and future
development patterns and proposals. Such a mechanism will require
the cooperation of many governmental agencies at the local,
regional, and state levels. Every agency with regulatory power
must accept some responsibility for implementation. It is also
necessary to coordinate decisions made by city, village, township
or county planning commissions, municipal administrators (zoning
officials, planners, traffic engineers, etc.), county road
commissions, and the Michigan Department of Transportation.
Generally, an implementation process must be logical, responsible,
and relate access control to the health, safety, and general
welfare of the public. In accomplishing this, the comprehensive
plan, zoning ordinance, subdivision control ordinance, and public
investment schedules all become critical elements and should be
utilized to create, document, and implement access control
policies.
39
Comprehensive Plans
Comprehensive plans are a very important first step in establishing
an arterial access control program. This plan provides the
Information base and policy level commitment which lends continuity
and credibility to an entire access control implementation effort.
Key features which are incorporated in comprehensive plans are:
ù Development of a rationale for establishing regulatory
controls
ù Indicates commitment of a community to the concepts of
access control
. Identifies growth areas and complements long range street
and highway plans by indicating arterials that will need
upgrading or reconstruction.
. Identifies and explains access control problems and their
ramifications.
. Identifies arterial and collector system and relates to
right-of-way requirements.
Zoning Ordinance
In order for an access control policy to become legally enforceable
it must be enacted in ordinance form. This is most commonly
accomplished through the use of a driveway/access ordinance or by
incorporating access control features into the overall municipal
zoning ordinance. Once municipal policy becomes ordinance it is
necessary to establish dimensional standards. Such standards
should be developed with great care to ensure their applicability
in a variety of situations. Examples of standards developed by
various jurisdictions are provided in Appendix B.
Some of the key features which should characterize a zoning ordi-
nance are:
. Establishes regulatory standards which reflect the policy
declarations of the comprehensive plan.
. Design and operational criteria against which development
proposals are judged shall include required frontage (lot
width), setback, driveway design dimensions, driveway
location, lot area, building dimensions, signs and
banners, permitted uses, etc.
. Should preserve potential for future right of way
acquisition and arterial improvements by maintenance of
adequate setback of developments from existing right of
way line.
. Should recognize the distinctions between arterial
highway business districts and other more nucleated
business areas in terms of spatial arrangements or
functional needs.
40
. Should be flexible enough to allow for site specific
considerations through the mechanisms of site plan
review, special use permits, and variances.
Zoning ordinance provisions or standards can be applied in a
variety of ways. For example:
. By integration of access control measures into all
existing zoning districts which abut arterials.
. By creation of specific highway oriented zoning districts
such as "Highway Commercial".
. By creation of an overlay district which would impose
additional regulations specifically concerned with access
control along designated arterials irrespective of
existing zoning. These "extra" regulations would most
likely deal with driveway design, driveway spacing and
driveway location, etc., rather than specific land uses.
Site Plan Review
Pre-determined dimensional or design standards cannot, and should
not, be indiscriminately applied in all situations. Many times
site specific conditions require special attention resulting in
site specific application of access controls. For this reason it
is critically important that a site plan review procedure be
developed and effectively utilized by a municipality.
Some of the key features to consider include:
. The municipality should work with developers and property
owners in designing effective access control features for
a particular parcel or parcels. There is nothing
inherent in the provision of access control which
necessitates an adversary relationship between the public
and private sectors.
. The review process should be systematic, integrated, well
documented, and should require a "sign off" by agencies
responsible for both land use controls and highway
operations for ultimate approval.
. Site plans can incorporate an integrated or separate
permit process. There can be issued a separate driveway
or access permit to each new development or, to avoid
cost and increased administration problems, access
control permission could be linked to an existing permit
process such as a building or occupancy permit.
41
. Site development plans should show access, internal
circulation, parking, grading, landscaping, screening,
access locations of adjacent development and those on
opposite side of street, type of street, number of lanes,
traffic volumes, building location, requested access
locations and design, and existing, driveway and
intersecting roadways 300 ft. on either side of proposed
development.
. An Informational pamphlet could developed outlining the
community's concern for maintaining the functional
integrity of major arterials. It should outline policy
position, regulations, and information that will be
required from a petitioner.
. Land adjacent to major roadways can r)ass through many
uses with varying access needs over the useful life of an
arterial. Thus, each time a parcel changes use, is
redeveloped, experiences an addition to existing use,
etc., a new site review should be made and a new permit
issued.
. Once a site plan is approved and permit issued, a
performance bond could be required to ensure proper
construction. Upon inspection of the completed site the
bond would be returned to the developer.
42
CONCLUSION
Conclusion
Establishing and enforcing an arterial access control program will
be a complex, frustrating and un-glamorous task. However, it is a
task which is becoming more important in the face of continuing
strip development and deterioration of traffic carrying capacity on
arterial streets. It is obvious that past and existing policies
have failed to alleviate these problems. Therefore, it is time to
revamp those policies and practices which have allowed this gradual
deterioration.
Just as the deterioration has been gradual the improvements
necessary to restore functional integrity will be gradual. The
time frame necessary to recondition many arterials may be 20 to 30
years. Thus, it will be very difficult to maintain access control
policies and justify their need because results will not be
forthcoming "overnight".
To achieve the goals of an access control policy traditional
separation between transportation and land use planning must be
bridged. In terms of access control the two are intricately
intertwined and this relationship must be realized if a truly
effective control program is to be established.
To effectively implement a comprehensive program a municipality
will have to restrict current access points to their existing use
and location, allow new driveways only under new location and de-
sign standards, eliminate hazardous access points, and encourage
upgrading of functionally inadequate driveways.
If these types of activities are undertaken a community can slowly
begin to reverse the process which created undesirable operational
characteristics along arterial roadways. The benefits which can
accrue to such efforts are great even if not readily apparent.
Also, it may be necessary for many municipalities to seek out
professional expertise in assessing access control policies and
implementation techniques. Such expertise may be available in the
form of county road commission engineers, Michigan Department of
Transportation engineers, or various consultants.
The costs involved in the provision of certain access control
implementation techniques will also be of paramount importance to
developers, land owners, and municipalities. This will be a
difficult issue and its resolution will depend upon the ingenuity
of a community to establish an equitable financing system.
Examples of such funding mechanisms include special assessment
districts which tax the land owners directly benefiting from such
improvements, a combined funding approach which divides the cost
between property owners and the municipality, or a municipality can
commit a certain portion of federal or state financial assistance
funds to access control improvements particularly on a corridor
level project.
43
APPENDICES
APPENDIX A
Access Control Strategies to.Achieve
Specific Functional Objectives
The following is a matrix relating access control/traffic
engineering techniques to specific goals and objectives of
efficient arterial street operation. A variety of functional
objectives are listed down the left side of the page. Directly to
the right of each objective are several techniques which could be
used to achieve that objective. Thus, if a specific access control
problem has been identified within a community these tables can be
used to gain initial insight into possible solutions.
Source - Technical Guidelines for the Control of Direct Access to
Arterial Highways, (J.C. Glennon, FHWA, 1975).
45
Click HERE for graphic.
Click HERE for graphic.
Click HERE for graphic.
APPENDIX B
Examples of Design Characteristics
for Major and Minor Arterials
The following five tables represent information from a variety of
reports published by transportation planners and engineers. Tables
1 and 2 are a synthesis of many of these reports and have been
included to provide examples of design standards. These standards
are intended only to provide a sense of scale, or a convenient
starting point, where local agencies can get some direction when
dealing with policy or ordinance formation. They are not hard and
fast standards and are not necessarily recommended as desirable in
all cases.
Table 3 is intended to provide the reader with a listing of zoning
standards that have actually been used by various municipalities
throughout the country. Again these are intended to provide a
sense of scale and for comparison purposes.
Table 4 lists some parameter of safe sight distance. When a
vehicle is stopped in a driveway preparing to enter the traffic
stream the driver should have a clear view of traffic to the right
and left. This distance varies with the type of street and type of
vehicle. Again, the distance listed in this table may not always
be applicable in all instances. However, they do serve as a
starting point.
49
TABLE 1
EXAMPLES OF DESIGN CHARACTERISTICS FOR MAJOR AND MINOR ARTERIALS
MAJOR MINOR
FEATURE ARTERIAL ARTERIAL
1.Primary function Movement Movement/Access
2.Right-of Way 120 to 175 ft. 90 to 120 ft.
3.Optimum operating speeds 35 to 45 mph 30 to 40 mph
4.Typical ADT 15000 + 7500 to 20000
(2 directions)
5.Number of movement lanes 4 to 6 2 to 4
6.On-street parking, loading Prohibited Prohibited except
in special cases
7.Minimum distance between 1320-2460 ft. 660-1320 ft.
signalized cross-street 1/4 to 1/2 (1/8 to 1/4
intersections* mile), should mile), should
be uniform on be uniform on a
on a given roadway given roadway
8.Minimum distance between 660 ft. (1/8 330 ft. (1/16
all intersections* mile), "T" inter- mile) cross-
sections street permitted
at 1/8 mile, "T"
intersections
recommended at
1/16 mile
9. Median width 14 ft. minimum needed to accommodate
left turns from roadway. 30 ft.
minimum needed for left turns onto
roadway. 70 ft. minimum needed if
substantial heavy-truck turning
movements anticipated.
10. Minimum distance between 350-500 ft. 325-350 ft.
Left turn lane should be 250 ft. with
75 ft. taper.
* Measurements are from center-line to center-line.
50
Click HERE for graphic.
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TABLE 5
PERCENT OF SIGNAL CYCLES WHICH QUEUES DO NOT BLOCK DRIVEWAY
Click HERE for graphic.
This information is valuable in determining adequate corner
clearance for driveways in terms of key operational features of an
intersection. Normally, recommended corner clearance is identical
for all types of arterials. However, it can be seen that certain
operational characteristics such as traffic volume, Red Phase
length of signal light, operating speeds, etc. directly relate to
the blockage of driveways near intersections. By assuring that
most movements can take place without being blocked by queues
forming at intersections, capacity of the intersection And arterial
can be facilitated by reducing the impact of turning movements.
56
APPENDIX C
Determination of Need for More
Than One Access Point Per PARcel
This discussion provides a methodology for determining if a
proposed development will generate enough traffic to warrant the
provision of more than one Access point.
57
DETERMINING NEED FOR MORE THAN ONE
ACCESS POINT PER PARCEL
Determination of Need for Additional Access
There are provisions for permitting additional access where the
scale of development warrants it. Two Basic approaches to granting
additional access are available. The first should be a "rule of
thumb" guideline. A 5000 vehicle per day (2500 vehicle trips per
day) warrant was arrived at by viewing the driveway as a stop-sign
controlled intersection. According to procedures in the Highway
Capacity Manual, the service volume of an uncontrolled or two-way
STOP sign controlled intersection can be estimated by substituting
the green/cycle ratio of a signalized intersection with a ratio
based upon the relative volumes and widths of the roadway and
driveway. The following assumptions were made in calculating the
5000 vehicle per day guideline:
Metropolitan Area Population 375,000
Locale Fringe Area
Unadjusted Road Factor 0.85
Driveway (Roadway) Approach 2-way, w/o parking
Driveway Width, Volume 30', 5000 vpd
Roadway Width, Volume 68', 25000 vpd
% Right Turns From Driveway (adj. factor) 30+% (0.85)
% Left Turns From Driveway (adj. factor) 30+% (0.80)
Adjustment For Truck/Bus none
The formula for calculating an intersection approach service volume
(i.e., the peak hour volume which could be handled by the exit land
from the site onto the roadway) is as follows:
SV = USV x GCR x RTA x LTA x TA x BA
where: SV = Service Volume
USV = Unadjusted Service Volume
GCR = Green / Cycle Ratio
RTA = Right Turn Adjustment
LTA = Left turn Adjustment
TA = Truck Adjustment
BA = Bus Adjustment
In this example, the unadjusted service volume for a two-way
driveway with an approach width of fifteen feet (half of the thirty
foot width) and load factor of 0.85, in a metropolitan area of
375,0000, in a fringe area is:
Unadjusted service volume = 1250 vphg x 1.03 x 1.25
= 1610 vphg.
These figures are taken from Figure 6.8, page 135 of the Highway
Capacity Manual.
The Manual substitutes the G/C ratio with a ratio based upon
volumes and roadway widths. In this example, the ratio is:
G/C Ratio =
Driveway Volume/Roadway Volume x Roadway Width/Driveway Width =
5000vpd/25000vpd x 68'/30' = 0.46
58
MDOT personnel recommended that a more likely split should be 35/65
thus, a G/C Factor of 0.35 is used in this example.
To complete this example, the service volume for a two-way, thirty
foot wide driveway is:
Service Volume = 1610 VPHG x 0.35 x 0.85 x 0.80
= 383 VPH.
Under the preceding assumptions, 383 vehicles per hour could exit
the site during peak traffic hours. Assuming that this figure
represents 75% of the total peak hour volume utilizing the
driveway, the total peak hour volume on the driveway might be 510
vehicles.
This example is typical of a development situation which will arise
in the Lansing urban area. Any site generating 5000 vehicle trips
per day or 21500 vehicles per day probably warrants an additional
access point(s).
The second method for permitting additional access is through a
competent traffic analysis. These studies should view driveways as
STOP sign controlled intersections, and utilize the formulas
provided above and the charts in the Highway Capacity Manual to
calculate service columns for the driveway.
59
APPENDIX D
Examples of Access Control/Land Use Plans
Appendix D contains three examples of combined access control land
use plans. They serve to indicate the close connections between
land use and transportation planning. The first of the three
examples was developed by the Genessee County Metropolitan Planning
Commission. The second two were developed by the Oregon Department
of Transportation and are elaborate examples of comprehensive land
use/access control plans which depict several stages of plan
development. These exhibits depict how a study area is chosen, the
comprehensive plan, and several stages of plan implementation.
61
EXAMPLES OF ACCESS CONTROL/LAND USE
PLAN
Figure 33 illustrates a "Coordinated Commercial Parking and Access
Program" developed in 1974 by the Genessee County Metropolitan
Planning Commission. It was designed to assist in the orderly
establishment of lot-by-lot commercial development along major
thoroughfares. This particular program necessitates that some one
individual or corporation must take the preliminary step. It
recognizes that should this individual be successful, others can
capitalize upon this success by locating in proximity of the
initiator, (in this case the first person is called the pioneer").
The pioneer, because of the risk he must accept, is felt to be
deserving of special consideration from the community. This
program, therefor, is designed to guide all subsequent developments
in accord with the initial design for parking and access that is
agreed to between the community and the pioneers. Implicit within
this system is the necessity for discussions and negotiations prior
to the establishment of the first enterprise.
The basic design measures of this program are based on three
principles:
1. The integrated parking serving all adjoining commercial
establishments provides convenience to the customers and
advantage to businesses.
2. The establishment of a median strip, between the main
thoroughfare and the parking area, contributes to traffic
safety and an aesthetically pleasing environment.
3. The limitation and lessening of the number of curb cuts
along public thoroughfare contributes to traffic safety.
As shown in Stage I, the pioneer sets the precedent for further
development along the roadway. This initial development is
approved after careful assessment of the unique characteristics of
the location. The decision is arrived at cooperatively as a result
of discussions between the pioneer and the community
representatives.
As shown in Stages II, III, and IV, subsequent developers are
accordingly required to conform with the established median design
and building setbacks. It should be noted that a key to the
successful implementation of this concept is that the controlling
governmental unit have the authority to open and close curb cuts as
necessary.
The next two examples, Figures 34 through 38, and 39 through 43,
illustrate long range access control plans that were developed by
the Oregon Department of Transportation. The first example is a
plan for a new or developing arterial, while the second deals with
remedial treatment for a previously developed arterial. Both of
these examples stress the need for cooperative and coordinated long
range planning, as well as the commitment and time necessary to
effect proper arterial design.
62
Click HERE for graphic.
EXAMPLE 1
DEVELOPMENT / REDEVELOPMENT OF A PARTIALLY DEVELOPED AREA
THE EXISTING SITUATION
This area consists of several businesses located near the
intersection. There are a few older homes on large parcels and a
duplex. Most of the land has not been developed. Every place is
served by at least one driveway. Each of the service stations has
four driveways while the store across from a service station has a
large undefined continuous access from the arterial and side
street. The service station across from the store is old with
gravel approaches and parking areas. The arterial is paved with
gravel shoulders on a 60-foot right-of-way. The current practice
allows the proliferation of driveways as each separate property is
developed.
Developed by
Oregon Dept. of Transportation
July 1979
64
Click HERE for graphic.
COMPREHENSIVE PLAN
The Comprehensive Plan calls for a commercial area surrounded by
medium density residential. The street network includes an
arterial with four moving lanes and no parking (east-west). A
collector intersects the arterial with two moving lanes (north/
south). The text of the plan sets a design speed (MPH) and
ultimate practical capacity for the arterial (vehicles per hour),
as well as rights-of-way setbacks.
The Comprehensive Plan policy relating to access Management states:
"The ultimate access to property shall be allowed from the cross
streets; no access shall be allowed from the arterial." This policy
is intended to ensure easy and safe access to the commercial areas
and at the same time provide for the smoothest possible flow of
traffic on the arterial. The intersecting streets serve two
functions near the arterial.
1. To provide easy ingress and egress to the commercial
area.
2. To provide an internal circulation route to residential
area.
An internal circulation system will be a requirement for individual
developments in the area. The system, when completed, will allow
the safe, smooth, and easy circulation of traffic as if the area
had been developed as a single project under one
ownership.
66
Click HERE for graphic.
ACCESS MANAGEMENT PLAN
This plan is designed to guide the development of large, various
sized properties under separate ownerships. Because the
comprehensive plan calls for the arterial to carry high volumes of
traffic at moderate speeds, direct access to the arterial is to be
replaced over time with access from the cross streets. Joint
circulation easements are to be required as a condition of approval
of each new development or remodeling of present uses.
The specific internal circulation routes will be finalized when the
preliminary plans are prepared. The points where these routes meet
the adjoining property need to be agreed to by the owners of the
adjoining property. The codes establish the amount of parking to
be provided, and the design and approval requirements for parking
lots. The creation of a parking association composed of property
owners and business people in the area is also a condition of
approval of all new developments. The local government will
provide a model agreement and will help establish the private
organization.
The points of access are designed for easy entrance and exit. Both
the public and private access improvements are designed to meet the
traffic volumes expected for the commercial area.
The plan recognizes that it is unlikely that all of the properties
would be developed at once and authorizes the use of temporary
access points. These temporary permits are issued with the
condition that they will be closed when a satisfactory alternate
access is available in the opinion of the local governing body.
Joint use of temporary access points will be required whenever
possible.
The amount of additional right-of-way necessary for the planned
street improvement sis shown so each property owner and developer
will know what will be expected. The plan also sets forth how this
land will be acquired. In addition, the plan indicates how much
right-of-way may be expected to be provided at no public cost as a
condition of development approval where the public is making street
improvements and adding traffic signals for private property
access. To help convey the plan to others who buy property after
the plan has been adopted, the plan could be recorded and all
affected property deeds referenced so that the provisions will
appear in title searches.
68
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FIVE YEARS AFTER PLAN APPROVAL
Some of the changes called for by the Comprehensive Plan and Access
Management Plan have occurred on an incremental basis during the
five years following adoption of the plans. A Local Improvement
District was formed. Through the district several old buildings
were removed and parking lots built for use by customers of firms
in the district. A restaurant was remodeled and a house converted
to an office. Conditions of permit approvals for both buildings
required that the parking areas be designed so traffic could
circulate to other lots and joint use easements be signed. A part
of one intersection was widened by the local jurisdiction as part
of the work necessary in closing some service station driveways and
combined the access with that for the new parking lot. The
widening made it possible to install a left turn lane.
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FIFTEEN YEARS AFTER PLAN APPROVAL
During the 10-15 years following approval of the plans, all of
the properties have been developed. The rest of the right-of-way
was obtained and the streets have been improved. Right and left
turn refuge lanes are provided at the entrances to the commercial
areas. The parking association constructed the entrances per their
joint agreement. As these improvements were made, access to the
arterials was closed.
The older service station was removed and a new one built oriented
to the interior of the development. The other station was
remodeled and new pump islands installed facing the frontage road.
72
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EXAMPLE 2
REDEVELOPMENT OF A DEVELOPED AREA
EXISTING SITUATION
This area along the arterial is completely developed with stores,
service stations, a bank, an older motel/restaurant and other
commercial uses. Many of the older commercial buildings are built
to the property line and street right-of-way. Only the newer firms
have off-street parking.
Numerous driveways provide access to the properties along the
arterial. The two-lane arterial has reached its capacity during
peaks and has a heavy volume during the rest of the day. This
discourages customers from coming to the area.
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COMPREHENSIVE PLAN
The plan designates the area next to the arterial for
continued retail and service commercial uses.
The text of the plan calls for the addition of off-street
parking to help revitalize the business area. A local improvement
district composed of affected property owners and businessmen is
suggested as a way to assist and finance some of the traffic and
parking improvements for this area.
The arterial will be improved to four lanes with off-street
parking removed. Refuge or deceleration lanes are encouraged
wherever possible so the smoothest possible flow of traffic can be
maintained.
Access to the commercial area is to be primarily from the
cross streets with signals at intersections to the arterial.
Driveways along the arterial will be removed to the maximum extent
possible.
76
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ACCESS MANAGEMENT PLAN
The plan is designed to improve automobile access to each business
and to develop off-street parking. The specific sites for off-
street parking have not been selected. The plan text establishes
the ratio of new parking spaces per square foot of commercial floor
area served.
The plan text also states that a Local Improvement District will be
formed to acquire the sites for parking, clear the land, and to
build, operate and maintain the parking areas. The sites are to be
identified and acquired over time as the property becomes
available. As each site is acquired, it is designed and built so
that when the remodeling of the area is completed there will be
easy access and understandable circulation routes through the
commercial area. Some parking lots may need to function separately
on an interim basis, perhaps using temporary driveways and
easements.
The commercial access route is not exactly pinned down, but the
principle of a two-way, through route is established. This leaves
the actual design to be worked out when a property or an easement
is obtained. A faster program could be implemented if the property
owners and business people desired. Otherwise the concept here is
a deliberate incremental approach, taking advantage of
opportunities as they arise, showing the benefits by examples and
respecting the fact that usually not all businesses want to remodel
at the same time. This use of time to achieve the public and
private sector purposes allows the programming of expenses to meet
the ability and schedule of each private and public participants
Because a relatively long period of time may be involved, it is
important that the public commitment be firm so everyone can count
on it.
Also the public is committed to the revitalization by agreeing to
make important intersection and access improvements. The public
benefit accrues with safer, more free traffic movement. Also,
improving the value of the commercial area will help the local tax
base and keep down other public costs like police, fire protection,
etc.
The access management plan states that every effort will be made to
close driveways fronting on the arterial street and the designated
commercial access portion of the intersecting streets. There may
be instances when this is not possible, then the plan states that
refuge lanes will be used except when it is absolutely impossible
to do so.
The plan also requires that any time a business is "substantially
changed, the access and parking will be modified consistent with
the access plan as a condition of any permit. This may include the
use of temporary access permits and similar interim agreements to
allow incremental development to occur which ultimately will result
in the remodeling of the business section into one that fits with
the auto-oriented nature of the area.
78
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FIVE YEARS AFTER PLAN APPROVAL
During the five years following approval.of the Comprehensive
Plan and the Access Management Plan several new developments have
been built. Temporary driveways were necessary since none of the
properties were next to the cross streets. A signal has been
installed at the collector street intersection but the volume of
traffic has not warranted other improvements. Additional right-of-
way along the arterial was deeded to the local government. As
development commenced, the property owners worked out a rough
parking and traffic circulation plan with the assistance of the
public works office. This served as a guide in entering into the
joint circulation easements.
During the review of the proposed plans for the two projects
on the right hand side of the street, it became apparent that it
would not be possible to develop the preferred access to the cross
street. Consequently, the access management plan was amended and
the access point moved somewhat closer to the arterial street to
avoid a house.
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FIFTEEN YEARS AFTER PLAN APPROVAL
Sometime during the 10-15 year period following approval of
the plans the remodeling of the area has been completed. Traffic
circulates through the business area and there is an adequate
amount of off-street parking. Most of the driveways have been
removed and the intersections have been widened and signals
installed. Greater volumes of traffic move smoothly through the
area.
82
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LIST OF REFERENCES
(1) Box, Paul C., "Traffic Control and Roadway Elements -- Their
Relationship to Safety", Highway Users Federation for Safety
and Mobility. (1970)
(2) Ibid p. 4
(3) Staffield, Paul R., "Accidents Related to Access Points and
Advertising Signs in Study", Traffic Quarterly, January 1953.
(4) Peterson, A.O., and H. L. Michael, "An Analysis of Traffic
Accidents on a High Volume Highway", Purdue University (1966).
(5) Box, Paul C., "Traffic. Control and Roadway Elements -- Their
Relationship to Safety", Highway Users Federation for Safety
and Mobility (1970).
(6) Ibid. P. 3
(7) Bochner, Brian S., "Regulation of Driveway Access to Arterial
Streets", Barton-Aschman Associates, Inc., Evanston, Illinois
(1978).
(8) Ibid. p. 1
(9) Netherton, Ross D., Control of Highway Access., (Madison:
University of Wisconsin Press, 1963) P. 168.
(10) Michael, Harold L., "Opportunities in Transportation
Engineering Funding and Intersection Management", Institute of
Transportation Engineers Journal, March 1980.
(11) Ibid. p. 18
(12) Ibid.p. 18
(13) Dale,Charles W., "Procedures for Estimating Highway User
Costs, Fuel Consumption, and Air Pollution", U.S. Dept. of
Transportation Federal Highway Administration (March 1980).
(14) Ibid. pp. 6-10.
85
COMMISSION MEMBERS TRI-COUNTY REGIONAL PLANNING COMMISSION
REGULAR STAFF
CLINTON COUNTY
Herbert D. Maier, Executive Director
Daryl Kesler Arlene C. Madden, Chief of Management and
Budget
Earl Lancaster Jon W. Coleman, Chief of Planning
Robert Steinman
Robert VanDriesen, Treasurer
Virginia Zeeb
Roger Overway, Ex Officio
EATON COUNTY Report Prepared By: Jeffrey Kern
Assistant Planner
Albert Boyd, Secretary
Robert Clarke
Eldon Dymond
Edward Havitz
Richard Lomax
Alvin Starr, Leo Bagley, Transportation
Ex Officio Coordinator
Gerald Burger, Senior Data Systems
Coordinator
INGHAM COUNTY Ronald Darling, Environmental Programs
Coordinator
Phillip Ballbach
Steve Sandstedt, Land Use Coordinator
Alan Fox
Paul Stuhmer, Economic Development
Richard Kibbey Coordinator
Jean McDonald Doris Farr, A-95 Review Coordinator
Carlene Webster, Martyn Johnson, Assistant Planner
Vice-Chairman
Jeffrey Kern, Assistant Planner
Gary Swartz, Ex Officio
Paul Mazzarella, Associate Planner
Kiley Rankin, Information Coordinator
Robert Roller, Senior Planner
CITY OF LANSING
Jason Whitler, Assistant Systems
Lucile Belen Analyst
Jack Gunther, Chairman Susan Thayer, Bookkeeper
Howard Heideman Thelma Kingsley, Secretary
Janette Henderson Carrie Clinkscales, Public Information
Secretary
Patrick Lindemann
Jenifer Carter, Receptionist
Gerald Graves, Ex Officio
Epifanio Vargas, Jr., Chief Delineator
Scott Smith, Printer
