HomeMy WebLinkAboutASPEN RIDGE PUD PRELIMINARY - 50 92B - SUBMITTAL DOCUMENTS - ROUND 1 - TRAFFIC STUDYTHE WUERKER PUD
SITE ACCESS STUDY
FORT COLLINS, COLORADO
OCTOBER 1992
Prepared for:
Dr. Richard Wuerker
363 West Drake Road
Fort Collins, CO 80526
Prepared by:
MATTHEW J. DELICH, P.E.
3413 Banyan Avenue
Loveland, CO 80538
Phone: 303-669-2061
distribution of the approaching and departing traffic generated at
the proposed uses is a function of:
-_Geographic location within the City of Fort Collins;
- Location of employment and business centers which are likely
to attract trips from this area;
- Access to the site.
The short range trip distribution assumed 80 percent to/from the
north and 20 percent to/from the south. The long range trip
distribution made some modest adjustment to this since there will
likely be continued development to the south. However, trip
attractions will continue to be predominantly to the north.
D. Traffic Assignment and Intersection Operation
Using the vehicular trip generation estimates presented in
' Table 2 and the trip distribution assumptions, the site generated
traffic was assigned to the Shields/Fossil Creek intersection.
' Figure 5 shows the short range peak hour traffic assignment.
This assignment also includes a 3 percent per year increase in
background traffic assuming a 1995 future year. Table 3 shows the
' peak hour operation. Calculation forms are provided in Appendix
D. At the Shields/Fossil Creek intersection, operation will be
acceptable for all movements.
Given the short range peak hour traffic projections at the
Shields/Fossil Creek intersection, the following approach geometry
is recommended: 1) southbound Shields - one through/right-turn
lane with a 40 foot right -turn radius' and one left -turn lane to
the east leg of Fossil Creek Drive; 2) northbound Shields - one
right-turn/through lane and one left -turn deceleration/storage lane
(325 feet including taper); 3) eastbound Fossil Creek - one left -
turn lane (50 feet) and one right-turn/through lane; and 4)
westbound Fossil Creek one left -turn lane and one right-
turn/through lane. As part of the development of this property,
' the City of Fort Collins will require that one half of the arterial
cross section be built along the frontage of this property. The
full arterial width is 70 feet. Therefore, this developer will be
' required to pave Shields Street to a width of 35 feet west of the
centerline and construct the curb and gutter along this property.
This will extend for the 725 feet that this property borders
Shields Street. It is recommended that the new wearing surface be
extended to the east edge of the pavement in order to have a
uniform surface. Figure 6 shows the recommended geometry from
' 'The southbound through and right -turn volumes do not warrant
a full width deceleration lane based upon criteria in "Intersection
' Channelization Design Guide," NCHRPR 279, TRB,1985, Pg 63-65. A
40 foot radius will allow right -turning vehicles to slow to 15 mph
to make the turn to enter Fossil Creek Drive.
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SHORT RANGE PEAK HOUR TRAFFIC Figure 5
Table 3
Short Range
(1995) Peak Hour Operation
Level of Service
Intersection
AM
PM
Shields/Fossil Creek
EB LT
C
D
EB RT/T
A
A
WB LT
C
D
WB RT/T
A
A
SB LT
A
A
NB LT
A
A
Table 4
Long Range
(2010) Peak Hour Operation
Level of Service(*)
Intersection
AM
PM
Shields/Fossil Creek
EB LT
E (C/D)
E (D)
EB RT/T
A
B
WB LT
D (B/C/D)
E (C/D)
WB RT/T
A
A
SB LT
B
B
NB LT
A
B
(*) Level of service considering recent research pertaining to
vehicle delay.
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SHI LDS STREET
ISM
WUERKER P.U.D.
R
CONCEPTUAL STRIPING PLAN ON
SHIELDS STREET AT FOSSIL CREEK DRIVE
J
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NO SCALE
Figure 6
Fossil Creek Drive to the south property line of the Wuerker PUD.
Figure 6 shows how the transition can be accomplished from the
existing widening on the east side of Shields Street to the Wuerker
widening on the west side of Shields Street. This is done without
the need to acquire other private property in the area.
Figure 7 shows the long range peak hour traffic assignment,
which includes the background traffic on the area streets. By the
year 2010, it is assumed that Shields Street will be built to a
four lane arterial standard. Table 4 shows the peak hour operation
at the key intersections. Calculation forms are provided in
Appendix E. Operation is acceptable except for left -turn exits
from Fossil Creek Drive. This is based upon the 1985 Highway
Capacity Manual (1985 HCM) capacity technique for stop sign
controlled intersections. Recent research (Appendix F) indicates
that the 1985 HCM technique overstates the level of service. The
expected delay to these left turns will range from 14-28 seconds
per approach vehicle. This indicates that these left -turn exits
will operate in the level of service C/D categories. This
operation is acceptable.
Fossil Creek Drive is one mile south of the Harmony/Shields
signalized intersection. From the volume projections indicated in
this traffic study a signal would not be warranted at the
Shields/Fossil Creek intersection. Development of a park to the
north and west of the Wuerker PUD would not cause a traffic signal
to be warranted at this intersection. While the one mile spacing
may be an appropriate location, Fossil Creek Drive is near the
bottom of a north facing grade. From a vehicle braking
perspective, this location is not ideal. If signals are needed in
this vicinity, it is more appropriate that they be located 1000+
feet to the south of Fossil Creek Drive. The location would be a
function of future development and the street system in the area.
IV. Conclusions
The following summarizes the significant findings as a result
of this study:
- Traffic from the Wuerker PUD can be handled on the area
streets with various improvements.
- Current traffic operation at the area intersections is
acceptable.
- The Wuerker PUD will gain primary access to the street
system via Fossil Creek Drive, which will intersect with Shields
Street at a four legged intersection.
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Rounded up to nearest
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ALI
LONG RANGE PEAK HOUR TRAFFIC Figure 7
i�
' - With development of the Wuerker PUD in the short range, the
key intersections operate acceptably. Figure 6 shows the geometry
' that will be necessary with the implementation of the Wuerker PUD
in the next few years.
In the long range future, the key intersections will
' operate acceptably. During peak hours, eastbound and westbound left
turns at the Shields/Fossil Creek intersection will experience some
modest delays. These delays are acceptable at stop sign controlled
intersections on arterial streets.
- Traffic signals will not be warranted at the Shields/Fossil
Creek intersection. If signals become warranted due to future
development in the area, signals should be considered further south
along Shields Street.
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1 APPENDIX A
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MA7 i HE'N J. DELICH, P.E.
3413 BANYAN AVENUE
LOVELAND, CO 80538
TABULAR SUMMARY OF VEHICLE COUNTS
IALG1/U"3 R = Right turn
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S = Straight
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BEGINS
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North
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TOTAL
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fmm EAST
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R I S
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R I S I L I Total
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1 APPENDIX B
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EXECUTIVE SUMMARY
The Wuerker PUD is a proposed single family detached
residential development with a veterinary clinic on one lot. It
is located west of Shields Street and south of Harmony Road in Fort
Collins. The following summarizes the significant findings as a
result of this study:
- Traffic from the Wuerker PUD can be handled on the area
streets with various improvements.
- Current traffic operation at the area intersections is
acceptable.
- The Wuerker PUD will gain primary access to the street
system via Fossil Creek Drive, which will intersect with Shields
Street at a four legged intersection.
- With development of the Wuerker PUD in the short range, the
key intersections operate acceptably. Figure 6 shows the geometry
that will be necessary with the implementation of the Wuerker PUD
in the next few years.
In the long range future, the key intersections will
operate acceptably. During peak hours, eastbound and westbound left
turns at the Shields/Fossil Creek intersection will experience some
modest delays. These delays are acceptable at stop sign controlled
intersections on arterial streets.
- Traffic signals will not be warranted at the Shields/Fossil
Creek intersection. If signals become warranted due to future
development in the area, signals should be considered further south
along Shields Street.
I
Level of Service Criteria
for
Unsignalized Intersections
Level of service criteria for unsignalized intersections are stated
in very general terms, and are related to general delay ranges.
Analysis for a stop or yield controlled intersection results in
solutions for the capacity of each lane on the minor approaches.
The level of service criteria are then based on the reserve, or
unused, capacity of the lane in question, expressed in passenger
cars per hour (PCPH).
Reserve Capacity Level of Expected Delay to
(PCPfl) Service Minor Street Traffic
------
->400--------------------
A ----------------------------y---------
Little or no dela
' 300-399 B Short traffic delays
200-299 C Average traffic delays
100-199 D Long traffic delays
0-99 E Very long traffic delays
t F
When demand volume exceeds the capcity of the lane, extreme
delays will be encountered with queuing which may cause severe
congestion affecting other traffic movements in the
Intersection. This condition usually warrants improvement to
the intersection.
Reference: Highway Capacity Manual. Special Report 209,
Transportation Research Board, National Research
Council, Washington, D.C. 1985.
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r M= M= w M M M M M M M M = = M M
1985 HCM: UNSIGNALIZED INTERSECTIONS Paae-1
X XXXMX#XXIKtXX##XXY#Y'X##XXX#X#XX##XXXXXXXX##X#X#X##tXl:#XXXXXXX#X##X#XM.
IDENTIFYING INFORMATION
---------------------------------------------------------------------
AVERAGE RUNNING SPEED. MAJOR STREET.. 45
PEAK HOUR FACTOR ..................... 1
AREA POPULATION ...................... 120000
NAME OF THE EAST/WEST STREET......... fossil creek
NAME OF THE NORTH/SOUTH STREET....... shields
NAME OF THE ANALYST .................. mid
DATE OF THE ANALYSIS (mm/dd/yy)...... 10/21/92
TIME PERIOD ANALYZED ................. am)Pm 1992)1995 2010
OTHER INFORMATION....
INTERSECTION TYPE AND CONTROL
------------------------- -----------------------------------------
INTERSECTION TYPE: T-INTERSECTION
MAJOR STREET DIRECTION: NORTH/SOUTH
CONTROL TYPE WESTBOUND: STOP SIGN
TRAFFIC VOLUMES
---------------------------------------------------------------------
EB WE. NB SE,
---- ---- ---- ----
LEFT -- 1 0 11
THRU -- 0 498 281
RIGHT -- 33 2 0
NUMBER OF LANES
---------------------------------------------------------------------
EB WB NB SE
------- ------- ------- -------
LANES -- 1 1 1
CAPACITY AND LEVEL -OF -SERVICE Paae-3
---------------------------------------------------------------------
POTEN- ACTUAL
FLOW- TIAL MOVEMENT SHARED RESERVE
RATE CAPACITY CAPACITY CAPACITY CAPACITY
MOVEMENT v(pcph) c (pcph) c (pcph) c (pcph) c = c - v L0�
p M SH R SH
------------------------------------------------ -
MINOR STREET
WB LEFT 1 288 285 > 285 > 284 > C
> 525 > 488 >A
RIGHT 36 539 539 > 539 > 303 > A
MAJOR STREET
SB LEFT 12 662 662 662 649 A
IDENTIFYING INFORMATION
NAME OF THE EAST/WEST STREET...... fossil creel;
NAME OF THE NORTH/SOUTH STREET.... shields
DATE AND TIME OF THE ANALYSIS..... 10/21/92 am pm 19092 1995 2010
OTHER INFORMATION_...
= r M= r w= w M M M M w M M= M M=
1985 HCM: UNSIGNALIZED INTERSECTIONS Page-1
........... XY.... l itltZ Xi1...X2H...... ***........... f.X........ *..* .......
IDENTIFYING INFORMATION
AVERAGE
RUNNING SPEED. MAJOR STREET..
45
PEAK
HOUR
FACTOR .....................
1
AREA
POPULATION ......................
120000
NAME
OF
THE EAST/WEST STREET.........
fossil creek.
NAME
OF
THE NORTH/SOUTH STREET.......
shields
NAME
OF
THE ANALYST ..................
m.jd
DATE
OF
THE ANALYSIS (mm/dd/yy)......
10/21/92
TIME PERIOD ANALYZED ................. am pm 1992 1995 2010
OTHER INFORMATION....
INTERSECTION TYPE AND CONTROL
---------------------------------------------------------------------
INTERSECTION TYPE: T-INTERSECTION
MAJOR STREET DIRECTION: NORTH/SOUTH
CONTROL TYPE WESTBOUND: STOP SIGN
TRAFFIC VOLUMES
---------------------------------------------------------------------
EB WE. NB SE
---- ---- ---- ----
LEFT -- 5 0 17
THRU -- 0 433 445
RIGHT -- 10 - 4 0
NUMBER OF LANES
---------------------------------------------------------------------
EB WE, NE SB
----------------------------
LANES -- 1 1 1
CAPACITY AND LEVEL -OF -SERVICE Page-3
---------------------------------------------------------------------
POTEN- ACTUAL
FLOW- TIAL MOVEMENT SHARED RESERVE
RATE CAPACITY CAPACITY CAPACITY CAPACITY
MOVEMENT v(pcph) c (pcph) c (pcph) c (pcph) c = c - v Lr
p M SH R SH
------------------------------------------------ --
MINOR STREET
WS LEFT 6 246 242 > 242 > 236 > C
> 397 > 380 >B
RIGHT 11 584 584 > 584 > 573 > A
MAJOR STREET
SB LEFT 19 710 710 710 691 A
IDENTIFYING INFORMATION
-----------------------------------------------------------------
NAME OF THE EAST/WEST STREET...... fossil creek
NAME OF THE NORTH/SOUTH STREET.... shields
DATE AND TIME OF THE ANALYSIS..... 10/21/92 : am pm 1992 1995 2010
OTHER INFORMATION._..
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1985 HCM: UNSIGNALIZED INTERSECTIONS Fape-1
MYMMM:KMMMMtMXMMMMMMMMYMMMMMMMMMMY.MMMMMMMX.MMMMMMMMMMMMXMMMMMMMMM]:MMMM.
IDENTIFYING INFORMATION
---------------------------------------------------------------------
AVERAGE RUNNING SPEED. MAJOR STREET.. 45
PEAK HOUR FACTOR ..................... 1
AREA POPULATION ...................... 120000
NAME OF THE EAST/WEST STREET......... fossil creek
NAME OF THE NORTH/SOUTH STREET....... shields
NAME OF THE ANALYST .................. m.Jd
DATE OF THE ANALYSIS (mm/dd/yy)...... 10/21/92
TIME PERIOD ANALYZED................./aiA pm 1995
OTHER INFORMATION....
INTERSECTION TYPE AND CONTROL
- ------- ----------------------------------------------------------
INTERSECTION TYPE: 4-LEG
MAJOR STREET DIRECTION: NORTH/SOUTH
CONTROL TYPE EASTBOUND: STOP SIGN
CONTROL TYPE WESTBOUND: STOP SIGN
TRAFFIC VOLUMES
EB WB NE SB
---- ---- ---- ----
LEFT 15 5 5 15
THRU 1 1 545 305
RIGHT 5 40 5 10
NUMBER OF LANES AND LANE USAGE
EB WB NB SE
------- .-------------- -------
LANES 1 2
LANE USAGE L + TR L + TF
CAPACITY AND LEVEL -OF -SERVICE Paae-3
---------------------------------------------------------------------
POTEN- ACTUAL
FLOW- TIAL MOVEMENT SHARED RESERVE
RATE CAPACITY CAPACITY CAPACITY CAPACITY
MOVEMENT v(pcoh) c (ocph) c (pcph) c (pcph) c = c - v LOS
p M SH R SH
--------------- --------------------------------- -'
MINOR STREET
EB
LEFT
17
236
219
THROUGH
1
252
247
RIGHT
6
686
686
MINOR
STREET
WB
LEFT
6
249
242
THROUGH
1
251
246
RIGHT
44
505
505
MAJOR
STREET
SB
LEFT
17
623
623
NB
LEFT
6
616
816
219 203 C
> 247 > 246 > C
> 530 686 > 523 681 >A A
242 237 C
> 246 > 245 > C
> 493 505 > 448 461 >A A
623
816
IDENTIFYING INFORMATION
--------------------------------------------------------
NAME OF THE EAST/WEST STREET...... fossil creek
NAME OF THE NORTH/SOUTH STREET.... shields
DATE AND TIME OF THE ANALYSIS..... 10/21/92 am pm 1995
OTHER INFORMATION....
607 A
811 A.
�r rr rs r r r r r r r r r r r r r r r r
1985 HCM: UNSIGNALIZED INTERSECTIONS Page-1
xxxxxxx x.xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
IDENTIFYING INFORMATION
------------------------------------- --------
AVERAGE RUNNING SPEED. MAJOR STREET.. 45
PEAK HOUR FACTOR ..................... 1
AREA POPULATION ...................... 120000
NAME OF THE EAST/WEST STREET......... fossil creek
NAME OF THE NORTH/SOUTH STREET....... shields
NAME OF THE ANALYST.. ................ mid
DATE OF THE ANALYSIS (mm/dd/yy)...... 10/21/92
TIME PERIOD ANALYZED ................. am �1995
OTHER INFORMATION....
INTERSECTION TYPE AND CONTROL
----------------------------- ---- ---------------------------------
INTERSECTION TYPE: 4-LEG
MAJOR STREET DIRECTION: NORTH/SOUTH
CONTROL TYPE EASTBOUND: STOP SIGN
CONTROL TYPE WESTBOUND: STOP SIGN
TRAFFIC VOLUMES
---------------
EB WB NB SB
---- ---- ---- ----
LEFT 15 5 5 3U
THRU 1 1 500 485
RIGHT 5 15 5 20
NUMBER OF LANES AND LANE USAGE
---------------------------------------------------------------------
EE• WE, NB SB
----------------------------
LANES 2
LANE USA(-F _ - TF L T,.
CAPACITY AND LEVEL -OF -SERVICE Page-3
------------------- --------------------
POTEN- ACTUAL
FLOW- TIAL MOVEMENT SHARED RESERVE
RATE CAPACITY CAPACITY CAPACITY CAPACITY
MOVEMENT v(pcph) c (pcph) c (pcph) c (pcph) c = c - v LOS
p M SH k SH
------------------------------------------------ -.
MINOR STREET
EB LEFT
THROUGH
RIGHT
MINOR STREET
WB LEFT
THROUGH
RIGHT
MAJOR STREET
SB LEFT
NB LEFT
17 192
181
181
165
D
1 197
190
> 190 >
189
> D
6 542
542
> 414 542 >
407 536
>A A
6 193
184
184
179
D
1 195
188
> 188 >
187
> D
17 537
537
> 481 537 >
463 520
>A A
33 658
658
658
625
A
6 658
658
658
652
A
IDENTIFYING INFORMATION
NAME OF THE EAST/WEST STREET...... fossil creek
NAME OF THE NORTH/SOUTH STREET.... shields
DATE AND TIME OF THE ANALYSIS..... 10/21/97 : am(pm\1995
OTHER INFORMATION....
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APPENDIX E
1
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1985 HCM: UNSIGNALIZED INTERSECTIONS
Paae-1
SSYYXSSSSSSSSZ3ZYZZSSSSSSSSSZSSi2Y22X222Z2222222Y2222......ZZ22Y.ZZZY2
IDENTIFYING INFORMATION
---------------------------------------------------------------------
AVERAGE RUNNING SPEED. MAJOR STREET..
45
PEAK HOUR FACTOR .....................
1
AREA POPULATION ......................
120000
NAME OF THE EAST/WEST STREET.........
fossil creek
NAME OF THE NORTH/SOUTH STREET.......
shields
NAME OF THE ANALYST ..................
m.jd
DATE OF THE ANALYSIS (mm/dd/yy)......
10/21/92
TIME PERIOD ANALYZED... ..............
am pm 1995
OTHER INFORMATION... 2010
INTERSECTION TYPE AND CONTROL
-------------------- -----------------------------------------------
INTERSECTION TYPE: 4-LEG
MAJOR STREET DIRECTION: NORTH/SOUTH
CONTROL TYPE EASTBOUND: STOP SIGN
CONTROL TYPE WESTBOUND: STOP SIGN
TRAFFIC VOLUMES
E8 WB NB SE,
____ ____ ____
LEFT 20 5 10 15
THRU 1 1 845 470
RIGHT 10 40 15
NUMBER OF LANES AND LANE USAGE
---------------------------------------------------------------------
EB WB Ne SS
------- ------- ---- —
LANES 2 2
LANE liu,,r._ _ �. (, u•
CAPACITY AND LEVEL -OF -SERVICE Paae-S
---------------------------------------------------------------------
POTEN- ACTUAL
FLOW- TIAL MOVEMENT SHARED RESERVE
RATE CAPACITY CAPACITY CAPACITY CAPACITY
MOVEMENT v(pcph) c (pcph) c (pcph) c (pcph) c = c - v LOS
P M SH R SH
MINOR STREET 1p-24-
EB LEFT 22 114 104 104 82 E
THROUGH 1 122 118 > 118 > 117 >
RIGHT 11 744 744 > 501 744 > 489 733 >,
MINOR STREET u - L I
WB LEFT 6 119 113 113 107 D
THROUGH 1 121 117 > 117 > 116 > D
RIGHT 44 591 591 > 537 591 > 492 547 >A A
MAJOR STREET
58 LEFT 17 365 365 365 349 8
N8 LEFT 11 592 592 592 581 A
IDENTIFYING INFORMATION
NAME OF THE EAST/WEST STREET...... fossil creek
NAME OF THE NORTH/SOUTH STREET.... shields
DATE AND TIME OF THE 94,�IS..... 10/21/92 am Pm 1995
OTHER INFORMATION.... 2010
M = = M = = = = = = M = M M M = r
1985 HCM: UNSIGNALIZED INTERSECTIONS Page-1
zzs««z«sszzxxzssss«zszzsszxx«ssszsz«xs«xzsz«z«««zzzzzssx«««x«z«zz«zz»
IDENTIFYING INFORMATION
------------------------ --------------- ---------------------------
AVERAGE RUNNING SPEED. MAJOR STREET.. 45
PEAK HOUR FACTOR ..................... 1
AREA POPULATION ...................... 120000
NAME OF THE EAST/WEST STREET......... fossil creek
NAME OF THE NORTH/SOUTH STREET....... shields
NAME OF THE ANALYST .................. mjd
DATE OF THE ANALYSIS (mm/dd/yy)...... 10/21/92
TIME PERIOD ANALYZED ................. am%p 1995
OTHER INFORMATION.... 2010
INTERSECTION TYPE AND CONTROL
------------------------------------------------------------------'
INTERSECTION TYPE: 4-LEG
MAJOR STREET DIRECTION: NORTH/SOUTH
CONTROL TYPE EASTBOUND: STOP SIGN
CONTROL TYPE WESTBOUND: STOP SIGN
TRAFFIC VOLUMES
--------------------------------------------------------------------'
EB WB NB SB
---- ---- ---- ----
LEFT 20 5 10 30
THRU 1 1 775 750
RIGHT 10 15 5 25
NUMBER OF LANES AND LANE USAGE
EB WB NB SB
------- -------------- -------
LANES 2 2 2 2
LANE USAGE L 4 TR L + TR
CAPACITY AND LEVEL -OF -SERVICE Page-3
---------------------------------------------------------------------
POTEN- ACTUAL
FLOW- TIAL MOVEMENT SHARED RESERVE
RATE CAPACITY CAPACITY CAPACITY CAPACITY
MOVEMENT v(pcph) c (pcph) c (pcph) c (pcph) c = c - v LOS
p M SH R SH
------------------------------------------------ -
MINOR STREET I`6--LcS
EB LEFT 22 83 76 76 54 E
THROUGH 1 86 80 > 80 > 79 > E
RIGHT 11 619 619 > 384 619 > 372 608 >8 A
MINOR STREET 16_Z(o
WB LEFT 6 83 76 76 71 E
THROUGH 1 84 79 > 79 > 78 > E
RIGHT 17 617 617 > 432 617 > 414 600 >A A
MAJOR STREET
SB LEFT 33 401 401 401 368 B
NB LEFT 11 404 404 404 393 B
IDENTIFYING INFORMATION
-------------------------------------------------------
NAME OF THE EAST/WEST STREET...... fossil creek.
NAME OF THE NORTH/SOUTH STREET.... shields
DATE AND TIME OF THE IS..... 10/21/92 ; am &1995
OTHER INFORMATION..._ 2010
I. Introduction
The Wuerker PUD is a proposed a single family detached
residential development and a veterinary clinic, located one mile
south of Harmony Road and west of Shields Street in Fort Collins,
Colorado. The site location is shown in Figure 1.
Figure 2 shows the area street system, existing and future.
Land to the west and north of the Wuerker PUD is in agricultural
use (grazing). To the south and to the east (across Shields
Street) are large lot residential dwelling units. These dwelling
units appear to have provision for animals (horses). It is
expected that the property to the north (extended to the west) will
be a city park. The size of the park is not known, but it is
expected to be a park with passive activities (no ball fields,
etc.). This park will have access via Fossil Creek Drive to
Shields Street. If this expectation changes, it is recommended
that further traffic analyses be performed evaluating a different
land use. The center of Fort Collins lies to the north of the
Wuerker PUD.
Shields Street is classified as an arterial on the Fort
Collins Master Street Plan. It is a street of varying width south
of Harmony Road. The segment adjacent to the Wuerker PUD has a two
lane rural cross section. North of Fossil Creek Drive, Shields
Street has a three lane cross section. It has curb and gutter on
the east side and a shoulder on the west side. It is proposed to
have a four lane urban cross section with turn lanes at appropriate
locations in the future. It is posted at 45 mph in this area.
There is a traffic signal at the Shields/Harmony intersection to
the north.
Fossil Creek Drive is a local street east of Shields Street.
' It intersects Shields Street at a T intersection with stop sign
control. It serves a residential subdivision to the east.
II. Existing Conditions
' The most recent daily traffic counts were obtained in 1991.
These counts indicate that the two way volume on Shields Street in
the vicinity of Fossil Creek Drive is about 7700 vehicles per day.
Peak hour intersection counts were obtained in October 1992 at the
Shields/Fossil Creek intersection. These counts are shown in
Figure 3. Raw data is shown in Appendix A.
' With the existing control at the counted intersection, the
peak hour operation is shown in Table 1. Descriptions of level of
service from the 1985 Highway Capacity Manual for unsignalized
intersections are provided in Appendix B. Calculation forms for
the operation shown in Table 1 are provided in Appendix C. At the
' 1
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APPENDIX F
1
iiv i LAAWRJyiv 1PV11N ZDLA-, i 1"IN
BOISE, IDAHO JULY 15-18, 1990
Compendium of
Technical Papers
Institute Of Transportation Engineers
43rd Annual Meeting
Boise, Idaho
July 15-13, 1990
M
Intersection Delay At Unsignalized Intersections
Matthew J. Delich, P.E.
Private Consultant
Loveland, Colorado
ABSTRACT
The technique described in the Hi hwa
Capacity Manual. Special Report 209, Chapter
10, Unsignalized Intersections relates a calcu-
lated reserve capacity to level of service to a
very unspecific description of expected delay.
The signalized intersection technique in the
Highway Capacity Manual relates level of
service to a range of stopped delay per vehicle.
It would seem to be consistent to relate level
of service at an unsignalized intersection to a 13
range of actual delay per approach vehicle —
This research provides some limited data on
intersection delay related to the calculated
reserve capacity at selected T-intersections. At
the time traffic volumes were collected, inter-
section delays were also obtained for selected
movements. The intersection delay technique
is described in the Manual of Traffic Engineer -
in Studies, ITT, 1976, Chapter 8. By compar-
ing the calculated reserve capacity using the
counted traffic volumes to the observed aver-
age delay per approach vehicle, a table of
delays per approach vehicle could be deter-
mined. This, in turn, could be plotted to
determine a range of delay given a calculated a
level of service.
INTRODUCTION
The means of evaluating the operation at an
unsignalized intersection is by determining the
level of service. The procedure in the 1985
Highway Capacity Manual (HCM) is primarily
145
taken from a German document (reference 1),
which uses gaps in the major traffic stream
utilized by vehicles crossing or turning through
that stream.
In the HCM, the level of service is related to
vehicle delay. This is especially true in the
evaluation at a signalized intersection. Howev-
er, in the case of an unsignalized intersection,
level of service is related to a nebulous mea-
sure of delay that can mean different things to
different people.
RESEARCH OBJECTIVES
This research was undertaken to relate level of
service to a definitive range of vehicle delay
for the minor street traffic flow. The objec-
tives of the research were:
1. Compare the level of service (reserve
capacity) to a range of vehicle delay, in
seconds, for the stopped traffic on the
minor street.
2. Determine a curve which best de-
scribes that range of vehicle delay.
RESEARCH API'ROACH AND LIMITA-
TIONS
Traffic counts were conducted at a number of
stop sign controlled intersections in Fort
Collins, Colorado and Cheyenne, Wyoming.
These volumes were used to determine reserve
capacity in passenger cars per hour (pcph)
Intersection Delay At Unsignalized Intersections
according to procedures documented in the
HCM. Highway capacity software developed
by the Federal Highway Administration, U.S.-
D.O.T. was used to perform these calculations.
Along with the traffic volumes, vehicle delay
was measured for each approach vehicle
according to procedures described in Chapter
8, "Intersection Delays," Manual of Traffic
Engineering Studies.
Due to changes in critical gap size due to
speed, number of lanes on the major street,
and number of legs at the intersection, only T-
intersections were evaluated. Further, in all
cases, the major street was five lanes (4
through lanes and one left -turn lane) and the
speed limit on the major street was 35 mph.
INTERSECTION DELAY STUDY
At the time traffic volumes were obtained at
each of the intersections, traffic delays were
also obtained for both right- and left -turning
vehicles from the minor street. The methodol-
ogy used was a procedure which involved
counting the number of vehicles occupying an
intersection approach (right- or left -tutu lanes
constitute two approaches) at successive time
intervals for the observation period. The
successive time interval selected was every 15
seconds. Each successive count represented
an instantaneous density or number of vehicles
occupying the intersection approach per time
interval. These counts were accompanied by
total volume counts of each approach. The
average delay per vehicle in each approach can
be expressed by:
D=Nt/V
where:
D = Average delay per approach vehicle
N = Total density count, or the sum of vehi-
cles observed during the periodic density
counts each t seconds
t = Time intervals between density observa-
V = Total volume entering the ap-
proach during the study period.
A total of 61 fifteen minute observations were
conducted. The average delay per approach
vehicle for both right and left turns for each
observation was tabulated. The ca' ed
delays were rounded to the nearest ...pole
second. The calculated delay per approach
vehicle for right turns ranged from 2 seconds
to 29 seconds. The mean was calculated at 9.9
seconds. The calculated delay per approach
vehicle for left turns ranged from 6 seconds to
105 seconds. The mean was calculated at 27.0
seconds.
LEVEL OF SERVICE CALCULATION
Using the same 15 minute periods from the
intersection delay study portion of this re-
search, level of service calculations were per-
formed Since the level of service calculation
requires hourly traffic, the volumes for each 15
minute period was factored by four. This not
only gives an hourly volume, but also assumes
a peak hour factor of 1.0.
Reserve capacity in passenger cars p iur
(pcph) was tabulated for the right tut,.- and
left turns for each observation. The calculated
reserve capacities ranged from 36 to 882 pcph
for the right turns. The mean was calculated
at 565.5 pcph. Most of the calculated levels of
service were in the A category (> 400 pcph).
The calculated reserve capacities ranged from -
75 to 241 pcph for the left turns. The mean
was calculated at 66.9 pcph. Most of the
calculated levels of service were in the D
category (100-200 pcph), E category (0-100
pcph), and F category (< 0 pcph).
ANALYSIS
Using the output data for right turns and left
turns from the delay study and the capacity
study, each corresponding observation point
was olotted and least squares graphical analvsis
Figure 1 shows the plot of calculated reserve
capacity versus calculated delay per approach
vehicle for the right turns. The results of the
graphical analysis are also plotted. By calculat-
ing confidence interval as a range of delay per
approach for each calculated reserve capacity,
a reasonable prediction of delay can be made.
For example, a calculated reserve capacity of
400 pcph would yield a delay per right-tum
approach vehicle of 10-15
seconds.
Figure 2 shows the plot of calculated reserve
capacity versus calculated delay per approach
vehicle for left turns. The results of the
graphical analysis are also plotted. Using the
confidence interval, a prediction of the range
of delay can be made. However, the data for
the left turns is all in the -100 to +200 range
of values. Therefore, the delay for left turns
is only valid for reserve capacities at the lower
end of the scale using the data considered in
this 'study. For example, a calculated reserve
'capacity of 100 pcph would yield a delay per
left-tum approach vehicle of 12-22 seconds.
The size of this range indicates that more data
is needed to reduce the prediction range.
CONCLUSIONS
Given the limited data obtained (61 observa-
tions), it appears as though the methodology
can give a reasonable indication of the range
of delay for vehicles entering a street at a stop
sign controlled T-intersection. However, more
data is needed to fill in gaps:
Data is needed at intersections where
the right turns operate at levels of
service B, C, D, E
Data is needed at intersections where
the left turns operate at levels of ser-
vice A, B, C.
At a number of the analyzed intersections,
there were signals upstream from the analyzed
intersections. Some of these signals were as
147
close as 1/4 mile away. There was no signal
progression pattern on the major street.
However, it was noticed that both operation
and delay were influenced by vehicle queues
created by the signals on the main street. This
was not accounted for in any of the calcula-
tions or analyses. An effort should be made to
select intersections which are not affected by
main street signals.
The statistical analysis on this data and addi-
tional data should be much more rigorous than
that used in this analysis. The curves devel-
oped using all the data should be mathemati-
cally derived and adequately tested using
accepted statistical practices.
The data presented is only for a T-intersection
with a four -lane (plus left -turn lane) main
street with a posted speed of 35 mph. Data
should also be collected at a number of main
street posted speeds (45 mph and 55 mph).
Data should also be collected for a T-intersec-
tion on a two-lane street at various posted
speed limits.
If the additional data and analyses for a T-
intersection point toward the validity of this
approach, then similar data should
be collected and analyses performed at four -
leg intersections.
BIBLIOGRAPHY
Box, Paul D. and Joseph C. Oppenlander,
PhD. Manual of Traffic Engineerine Studies,
4th Edition. Arlington, Virginia: Institute of
Transportation Engineers, 1976, Pgs. 106-112.
Roess, Roger P. et al. Highway Capacity
Manual, Special Report 209. Washington,
D.C.: Transportation Research Board, 1985,
Chapter 10.
REFERENCE
1. "Merkblatt for Lichtsignalanlagen an Land-
strassen Ausgabe 1972", Forschungsgesellschaft
Intersection Delay At Unsignalized Intersections
fur das Strassenwesen, Koln, Germany (1972).
m m m = m ! m = = = m m m m m m m m
u
0
a
RESERVE CAPACITY (pcph)
COMPARISON OF RESERVE CAPACITY AND DELAY
FOR RIGHT TURNS AT A T-INTERSECTION
1dQ
District 6 1990 Annual Meeting
Intersection Delay At Unsignalized Intersections
RESERVE CAPACITY (PcPh)
COMPARISON OF RESERVE CAPACITY AND DELAY
Figure 1 FOR LEFT TURNS AT A T-INTERSECTION Figure 2
1
1
1
INTRODUCTION
1
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1
A METIIODOIAGY FOR USING DELAY STUDY DATA
IO ESTIMATE THE EXISTING AND FUTURE LEVEL OF SERVICE
AT UNSIGNALIZED INTERSECTIONS
By Marni Heffron (A)o and Georgy Bezkorovainy (M)b
The level of service at unsignalized intersections is
often overstated by the 1985 Highway CepaClty
Manual (ITCH) methodology. The HCM analysis for
unsignalized intersections may show a LOS E or LOS F
operation with lengthy delays and, presumably, long
queues. However, from field observation, the
intersection functions relatively well with short
queues and minor delays on the approaches controlled
by STOP signs and no delays to mainline traffic. Many
reviewing agencies require the use of the HCM
methodology to determine level of service. However,
IICM states that "because the methodologies Ifor
calculating unsignalized level of service] result in a
qualitative evaluation of delay, it is also
recommended, if possible, that some delay data be
collected. This will allow for a better
quantification and description of existing operating
conditions at the location under study." HCH does
not, however, include a methodology to relate delay
study results for an unsignalized intersection with a
level of service designation.
IICM defines the level of service of an unsignalized
Intersection using "reserve capacity", an
analytically -defined variable that is not easily
field -verified. The procedure is based on the German
method of capacity determination at rural
intersections. This method has not been extensively
validated or calibrated for U.S. conditions, nor does
It estimate delay in quantitative terms.
This paper presents a methodology to use delay study
data to determine the existing level of service and to
estimate future operating conditions at unsignalized
intersections. In developing the methodology, delay
studies -were performed at more than 50 unsLgnalized
T-intersections in eastern and central Massachusetts.
Minor approaches of these intersections were
controlled by stop signs, yield signs and uncontrolled
(implied yield). The results of these delay studies
will also be compared to the delay calculated using
the IICM unsignalized intersection analysis.
This paper relies on the existing HCM methodology as
the basis to estimate existing and future level of
service from delay data. Until changes are made in
the HCM procedure, the existing IICM methodology for
unsignalized Intersections will continue to be
modified to yield results that better approximate
existing and future conditions.
a Transportation Engineer
Bruce Campbell 6 Associates, Boston MA
b Vice President
Bruce Campbell 6 Associates, Boston MA
UNSICNALIZED INTERSECTION DELA
Delay was adopted as a measure of effectiveness for
signalized intersections in the 1985 HCM for many
reasons; two reasons are that the concept of delay is
understood by the user community and delay can be
measured in the field.3 The application of delay
for unsignalized intersections should follow this same
reasoning. The.Xeserve capacity is related to
average vehicle delay using the following equation
from the ITE Handbook2:
1_ (1)
d (a - b)
d — average delay
a — service rate
b — side -street arrival rate
Recognizing that capacity is the service rate and
volume is the arrival rate at an unsignalized
intersection, this formula shows that the average
vehicle delay is the reciprocal of reserve capacity.
The average seconds of delay per vehicle is calculated
using the following equation:
Average Delay (sec/veh) " 3600 (sec/hr) (2)
Reserve Capacity (veh/hr)
Table 1 shows the level of service designations which
correspond to reserve capacity and average vehicle
delay. Because the average delay per vehicle
approaches infinity as the reserve capacity goes to
zero, LOS F will be defined by any delay over 60
seconds. The average delay values for unsignalized
intersections shown in Table 1 are very similar to the
delay valuns used to define the level of service of
signalized intersections. Table 1 is taken from Table
10-3 in the HCM.
Table 1
Level -of -Service Criteria
For Unsignalized Intersections
Average **
Level of Reserve Capacity Stopped Delay
Service (Pass Cars Per Hour) (sec/veh)
A > 400 < 9.0
B 300 - 399 9.1 to 12.0
C 200 - 299 12.1 to 18.0
-D "100 - 199 18.1 to 36.0
E 0 - 99 36.1 to 60.0
F * > 60.0
* Demand exceeds capacity; extreme delays will be
encountered
** Calculated from Equation (2)
' —1—
EASURED DEIAX VS CAI.CLI ED DEIA
Delay studies at unsignalized intersections are
relatively easy to perform and can be performed in
conjunction with a turning movement count at low
volume intersections. The observer measures the time
between when a vehicle stops for a stop sign or 1.
conflicting traffic and pulls onto the major street. 13
The measurement includes the time waiting in queue. ,F
The stopped delay is measured for random vehicles 11
turning left or right from the minor street or turning to
left from the major street. The average delay during
the peak hour is calculated using a modified
signalized intersection delay equation: °
_ 1
Total Delay (sec) (3) e
Average Daley (sec/veh) ' Number of Observations -
For locations with a shared lane for left and right
turns on the minor street, the stopped delay for each
movement should be kept separate if future conditions
will be projected from the data since the level of
service of each movement is calculated separately and
then combined as a shared lane movement. Special
consideration, discussed later, should be given to
shared lane approaches where the right turn delay will
be increased by a high left turn volume. The existing
level of service for the shared lane is the weighted
average of the combined movements.
Bruce Campbell b Associates performed delay studies at
more than 50 unsignalized intersections in eastern and
central Massachusetts. For all study locations, a
traffic count was also performed, and the level of
service was calculated using the HCM methodology. To
date, only a few delay studies have been performed at
4-legged Intersections, so only the data for
T-intersections are included in this paper. The
average delay per vehicle was calculated using
equation (3). Figures 1 through 3 compare the results
of the measured delay and the calculated delay. The
curves are from regression equations relating
conflicting flow and average delay. At this point
there have been no attempts to correlate the delay
data to another variable such as speed, movement
demand or type of control.
For all three critical movements at an unsignalized
intersection --the left turn from the minor street,
right turn from the minor street and left turn from
the major street --the measured delay was found to be
shorter than the calculated delay. These data suggest
that drivers are selecting smaller gaps than those
recommended in the 1965 FICM. Using the methodology
described below to back -calculate to the critical gap,
it was found that at over 80 percent of the locations,
the critical gap for both the minor left and right
turn movements was less than 6.0 seconds.
it was originally suspected that the smaller gap size
determined for the study locations would result in
higher accidents rates at these locations. However,
most of the intersections studied had accident rates
less than 0.5 Acc/Million Entering Vehicles, and none
had accident rates over 2.0 Acc/HEV. In
Massachusetts, intersections with an accident rate of
less than 2.0 are not considered high accident
locations.
100
90
so
,a
as
FIGURE 1
CON FLIC111JG FLOW VS. AVERAGE DELAY
1 Ff 1 I I AtN I R(I )M AMIUR Sl RiII--
o va --
IThousendsl
C01`6LIC1 m riow
FIGURE 2
CONFLICTING FLOW VS. AVERAGE DELAY
LOFT TURN IROM MINOR SIREEI
�PSEO
! I t
I i I
hAEASUREO
i II
i
a.° a.. 0.e 0.8 1 1.2 L.
(Thmsonds)
CONFLICIM FLOW
EIGUHE 3
CONFLICTING FLOW VS. AVERAGE DELAY
RN;iI IF
IIRN FROM INOR SI REET
(ThoOSOnds1 00
CO" [IC IING FLOW
LAI ED
MEAS�(EO
1
1
[1
1
Intersections with a shared lane on the minor approach
provided conflicting results for the left and right
turn movements. In many cases, the critical gap
determined from the delay data for the right turn was
higher than the gap determined for the minor left
turn. This phenomenon is most likely due to the time
a right turner spends waiting in queue behind a left
turner. Because of the queue, the measured delays for
the two movements were not dramatically different.
Since the critical gap calculation relies on the
movement's conflicting flow, the right turn gap
calculates to a higher value than the left turn gap.
Generally, the minor left turn is the most critical
movement at an intersection, and the delay data for
the left turn is not significantly affected by a
shared lane. In retrospect, if delay data
measurements did not include stopped delays in a
queue, then the calculated gaps would be higher for
left turns than right turns in all instances.
However, not recording delays in a queue would give an
unfair representation of existing field conditions.
To further illustrate the shared lane phenomenon
affecting right -turning vehicles, the results in
Figures 1 and 2 show a large disparity between the
calculated delays vs. measured delays. However, in
the case of right -turning vehicles, the measured
delays were only 2-3 seconds less than the calculated
delays. The presence of left -turning vehicles in the
shared lane had, most likely, a significant impact on
the delay values recorded for right -turning vehicles.
Further research on shared -lane approaches is needed.
ESTIMATING FUTURE LEVEL OF SERVICE
The following procedure is suggested to estimate
future level of service from existing delay data. It
relies on the existing HCM methodology, and basically
back -calculates from delay to capacity to determine
the gap being accepted by drivers. Once the gap is
determined, the future capacity and level of service
can be estimated using the same gap.
The capacity for an unsignalized intersection movement
can be determined from delay by rearranging equation
(2) as follows:
Capacity (veh/hr) - 3600 (sec/hr) . Side Street Demand (4)
Average Delay (see/veh)
The HCM equations relate critical gap to "potential
capacity." The potential capacity for the left turn
from the major street and right turn from the minor
street are the same as Capacity, but the capacity of
the minor left turn needs to be converted to potential
capacity discounting the impedance factor of the major
left turn. The impedance factor is determined using
the following equation 4 (the variable names
correspond to the variables in HCM):
r l
I— 1- 0.0038 1010 x V 1.2052 (5)
4 J
Cp4
I — Impedance Factor
V4 — Left turn volume from major street
Cp4 — Capacity of left turn from major street
The potential capacity of the minor left turn is then
calculated using:
Cm7 (6)
Cp7 I
C 7 — Potential capacity of the minor left turn
Cm7 — Actual capacity of the minor left turn
(determined from delay data)
Using Figure 10-3 in the 1985 HCM, the critical gap
can be estimated from the potential capacity and
conflicting flow, Alternatively, the equations in
Karsten G. Beggs' article "The Potential Capacity of
Unsignalized Intersections" (ITE Journal, October
1987, pp. 43-46.) can be used to determine the gap.
The estimated critical gap may be lower than 4.0
seconds for low volume Locations, but it is
recommended that 4.0 be the minimum gap used. HCH's
Figure 10-3 also `shows the minimum critical gap to be
4.0 seconds.
Once the critical gap is estimated from the delay
data, the future level of service at a location is
determined using the standard IICM methodology. This
methodology is not recommended for intersections with
high accident experience, or where vehicles on the
side street are forcing a gap in the major street
traffic stream. The following is an example of this
methodology's application:
EXAMPLE:
A delay study and turning movement count were
performed at the T-intersection of Lincoln Avenue and
Bristow Street in Saugus, Massachusetts. The PM peak
hour turning movement volumes and vehicle delays are
summarized below:
Average
Peek Hour Conflicting Delay per Maximum .Semple
Movement Volume flow Vehicle Delay Size
Minor Left 107 1227 13.7 64 92
Minor Right 33 653 5.4 28 31
Major Left 36 653 3.8 14 15
According to the HCH methodology, the left turn from
Bristow Street to Lincoln Avenue operates at LCS F.
The delay study data, however, show that the left turn
operates at LOS C.
The capacity of each movement is calculated using
equation (4).
Movement Demand Capacity
Minor Left 107 vph 370 vph
Minor Right 33 700
Major Left 36 983
The potential capacity of the minor left turn is
calculated using the impedance factor from equation
(5). The impedance factor is determined from the
demand and capacity of the major left turn,
I — 1 - 0.0038(100 x 36)1.2052 _ 0.98
983
and potential capacity, Cp7 — 370 — 378 vph
0.98
1
—3—
The conflicting flow of the minor left turn — 1227
'
vph. Using Figure 10-3 in the HCM, a critical gap Of
approximately 4.5 seconds is located for a potential
capacity of 378 and a conflicting flow of 1227. These
FIGURE
4
steps are illustrated in the flow chart in Figure 4.
ESTIMATING FUTURE
LOS FLOW CHART
'
Under the future conditions, the conflicting flow is
estimated to increase to 1400 vph, and the minor left
turn demand will increase to 170 vph. The future
Existing
Future
potential capacity located on Figure 10-3 is 300 vph
Conditions
Conditions
for a gap of 4.5 seconds and conflicting flow of 1400
vph.
The actual capacity accounts for the impedance factor
Measure
Future LOS
'
(for this example the impedance factor is assumed to
Delays
Table 1
be 0.98).
Cm7 — 300 x 0.98 — 294 vph
'
Avg. De i.py
Avg. Delay
The reserve capacity — 294 - 170 — 124 vph,
Per Vehicle
L
Per Vehicle
Equation•(3)
Equation (2)
and the average delay is calculated using equation (2),
'
Delay - 1240 — 29.0 sec.
Capacity of
Reserve Ca'--p.
The level of service for the future conditions will be
Movement
Subtract
LOS D.
Equation (4)
Demand
CONCLUSION
'
The methodology presented in this paper provides one
inter-
way to quantify the operation of an unsignalized
Impedance
Actual
section when the HCM methodology does not correlate
Factor
Capacity
with field observations. Future operating conditions
Equation (5)
Equation (6)
'
can also be defined on the basis of existing
conditions delay data. The delay methodology should
not be used for intersections with high accident
experience or where vehicles on the side street are
'
forcing a gap in the major street traffic stream.
potential
entialFurther
research is needed for intersections with a
Capacity
F_,_
acity fromshared
lane on the minor approach since the right turn
Equation (6)
Fig. 10-3
delay is affected by the left turn movement. Data
collected for the left turn movement on a shared lane
be affected.
approach should not significantly
Delay is a measure of effectiveness that should be
Critical Gap
Assume Same
applied to unsignalized intersections because it is
HCM Fig.
Critical Gap
'
easily measured end also easily understood. Future
10-3
for Future
revisions of the HCM methodology should include
delay.
1
'i
'
REFERENCES
Research Board, National Research
1. Transportation
Council. "Research Problem Statements: Highway
Capacity", Transporation Research Circular Number
'
319. Washington D.C., June 1987, page 27.
2. Institute of Transporation Engineers.
Handbook. 4.
Baass, Karsten G. "The Potential
Capacity of
Transporation and Traffic Engineering
499-536.
Unsignalized Intersections",
ITE Journal, October,
'
Prentiss Hall Inc.; 1982, pp.
1987, pp. 43-46.
3. Roess, Roger P. and McShane, William R. "Changing
5.
Transportation Research
Board, National Research
Concepts of Level of Service in the 1985 Highway
Council. Hiehwi Capacity
Manual, Special Report
Capacity Manual: Some Examples," ITE Journal, May
209. Washington D.C., 1985.
'
1987, pp. 27-31.
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NO SCALE
' SITE LOCATION
Figure 1
F-
W
W
Q
F-
N
N
G
J
W_
W
FUTURE
PARK SITE
WUE KER
P.U.D.%
AREA STREET SYSTEM
(Existing and Future)
41
N
NO SCALE
HILLDALE DRIVE
FOSSIL CREEK DRIVE
-EXISTING STREETS
- - - FUTURE STREETS
Figure 2
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4-
AM/PM
N
1992 PEAK HOUR TRAFFIC Figure 3
Table 1
Existing (1992) Peak Hour Operation
Level of Service
Intersection AM PM
Shields/Fossil Creek
WB LT
WB RT
SB LT
Land Use
24 D.U.
Veterinary Clinic
Total
C
A
A
Table 2
Trip Generation
Daily
A.M.
Peak
Trips
Trips
Trips
in
out
230
5
13
120
6
4
350
11
17
C
A
A
P.M. Peak
Trips Trips
in out
16 8
4 6
20 14
stop sign controlled
Shields/Fossil Creek intersection,
the
operation is acceptable.
Acceptable operation is defined as
level
of service D or better.
'
III.
Proposed Development
The Wuerker PUD is
a residential development consisting
of 24
single family lots and a
veterinary clinic on a parcel of land west
'
of Shields Street. A site plan showing expected phasing is
shown
in Figure 4.
'
A. Trip Generation
' Trip generation estimates for the Wuerker PUD were obtained
from Trip Generation, 5th Edition, ITE. Table 2 shows trip
generation on a daily and peak hour basis. The trip generation for
' the veterinary clinic was based upon conversations with
veterinarians in the Fort Collins/Loveland area.
' B. Background Traffic
Background traffic is defined as the traffic that is and/or
' will be on the area streets that is not related to the proposed
development. The intersection considered for the operations
analysis is Shields/Fossil Creek, which provides access to the
site. Other intersections, such as Harmony/Shields, were not
analyzed since the amount of traffic generated by the Wuerker PUD
is so small compared to the existing and future traffic at these
intersections.
Background traffic for impacted streets was projected for each
of the future years analyzed. Background traffic was projected to
' increase at 3 percent per year for the short range future. This
rate of increase is normal for streets and roads in the City of
Fort Collins. It accounts for general traffic growth and some
' level of continued development in the vicinity that would also
contribute to traffic growth. Long range background traffic
projections were made at the rate of 3 percent per year also, which
is in line with projections made in the North Front Range
Transportation Plan.
' C. Trip Distribution
Trip distribution was determined based upon an evaluation of
' attractions for home -based productions and the most likely routes
available to travel to those attractions. The directional
2
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INO SCALE
Future Park Site
x0 I
� s• I
C/Q
._ DRIVE
71
ETERINAR
_ CLINIC
r
Veterinary Clinic and 24 Dwelling Units
WUERKER P.U.D.
SITE PLAN
Emergency
Vehicle Access
L
W
M
I-
0
W
Figure 4