HomeMy WebLinkAboutA003 - Old Town Area Traffic Study - July 20, 1990 toll 11 Gault
TO: Mayor and City Council
FROM: Bob Kindred, Assistant City Manager
DATE: July 20, 1990
SUBJECT: Old Town Area Traffic Study Update
Several weeks ago, Council received a request from residents living on 9th
Street to consider alternative traffic control measures in the area between the
hospital/medical district and Downtown. Council directed staff to analyze traffic
movement and make recommendations regarding possible improvements to traffic
flow in the area.
The City's Traffic Engineer, Scott Logan, is presently completing work on a
comprehensive traffic flow analysis for the area bordered by 6th Street, Grand
Avenue, 13th Street, and Duff Avenue. Final data collection and preparation of
that report will be completed next week. Copies of that report will be
distributed to Council members and to representatives of the Old Town area.
A public meeting to present results of this study to area residents will be held
on Monday, July 30th, at 7:00 p.m. in the City Council Chambers. The Old
Town Neighborhood Association will assist in distributing announcements to
every household and business within the affected boundaries. Staff will see
that invitations to the meeting and copies of the report are sent to the Medical
Center and McFarland Clinic.
Our expectation is that input from the public meeting can be incorporated into a
final report to Council which will then be placed on the August loth agenda for
your consideration.
/lw
c: Steven L. Schainker, City Manager
Paul Wiegand, Public Works Director
Scott Logan, Traffic Engineer
Old Town Area
Traff ic Study
City of Ames
Traffic Department
McF
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July 1990
Old Town Area Traffic Study
Council during the June 12th meeting requested from staff a
traffic study for an area bounded by Duff Avenue, Grand Avenue, 6th
Street, and 13th Street. Staff has concluded this study and has
detected traffic problems, especially along north and south
streets. This report discusses these problems and traffic control
strategies to reduce speeds, volumes, and accidents along the
residential streets of Clark Avenue, Wilson Avenue, Burnett Avenue,
Douglas Avenue, and Kellogg Avenue between 13th Street and 6th
Street.
This traffic study reviewed the following conditions in the
Old Town Study area.
1 . Traffic volumes
2 . Traffic patterns
3. Traffic patterns to the Hospital
4 . Traffic Speeds on north/south Avenues and 9th Street
5. Intersection accidents ( 1984 to 1990)
6 . School routes
7 . Bus routes
8. Stop/yield placements .
1
Traffic Volumes
Traffic on local streets is composed of two types : through
traffic, which is making trips with both trip ends outside the
neighborhood under consideration, and local traffic, whose travel
patterns include one trip end within the neighborhood. Local
traffic can be divided into five categories: three of these relate
directly to the land use of the neighborhood, and two to
miscellaneous service traffic:
1 . Traffic produced by residents of the neighborhood
2 . Traffic attracted to residences in the
neighborhood-visitors, domestic employees, and so forth.
3 . Traffic generated by nonresidential land uses which may
exist in the neighborhood.
4 . Sequential trips to service the area-such as postal and
other deliveries, garbage pickup, police patrols,
local bus services .
5. Traffic generated. by occasional activity withing the
neighborhood-construction projects, utility repair..
emergencies and so forth.
These categories of traffic enumerated above represent trips
generated by residential land use activities within the
neighborhood. The table below presents trip generation rates and
regression equations from a commonly used U.S. source which can be
used to obtain a rough estimate of the number of trips likely to be
produced and attracted:
Weekday Vehicle Trip Generation for Residential Areas
Dwelling Type Avg. Range Regression Equation
Trips per Dwelling Unit(DU)
Single Family Detached Homes 10.1 4.3-21.9 2.6+0.94 G, (DU) (R2=.959)
Apartments 6.1 0.5-11.8 51.0+5.92DU (R2=.932)
Residential Condominiums 5.9 0.6-11.8 2.6+0.84 G, (DU) (R2=.820)
Occupied Mobile Homes 4.8 2.3-10.4 No equation available
Source:Institute of Transportation Engineers.1987.
2
Applying these generation rates to north/south avenues in the
Old Town area, the estimated local traffic is shown in this table.
Estimated Local Traffic Volumes
Local
FFDouglas
Section Homes Apartment Traffic
Units Volume
e - 9th-12th 8 11 146
e - 6th-9th 12 40 360
Kellogg Ave - 9th-13th 24 29 414
Kellogg Ave - 6th-9th 10 56 436
Burnett Ave - 9th-13th 28 33 478
Burnett Ave - 6th-9th 11 43 368
Clark Ave - 9th-13th 31 27 472
Clark Ave - 6th-9th 13 42 382
Wilson Ave - 9th-13th 34 16 436
Wilson Ave - 6th-9th 14 40 380
This table does not account for the traffic generated from
the hospital parking lots, businesses, grocery stores, car lots,
churches and other traffic generators located along these streets .
Traffic volumes were collected for a 24 hour period on all
residential streets in this neighborhood. These volumes can be
compared with these estimated local traffic volumes . The 24 hour
period was selected due to the time element for counting all
streets and concluding this study. With this count period, volume
fluxations for traffic flow was expected to be not greater than 10%
for any other traffic period.
3
Results
Traffic volumes varied widely on the north and south streets .
The heavier volumes were on Clark and Kellogg Avenues which are
located midpoint between Grand and Duff Avenue, and are adjacent to
larger generators such as the hospital, grocery stores, businesses,
etc. The traffic counts taken during the June and July, 1990, are
shown below.
AVERAGE DAILY
TRAFFIC COUNTS
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City Hal CITY OF AMES
i i 5tr,s�e Traffic Department
4
These traffic volumes indicate that more than 1,000 through
trips are occurring along Kellogg and Clark Avenue. The expected
local traffic is approximately 500 vehicles per day on these
streets.
These traffic volumes also indicate that heavier traffic than
typical residential traffic is being experienced on Clark,
Burnett, and Kellogg Avenues . Shown below in the table is an
approximate guide for classifying average daily traffic (ADT)
volumes on residential streets .
Residential Traffic Traffic
Classification Volume
Light 250 - 500 ADT
Medium 500 - 1,000 ADT
Medium - Heavy 1,000 - 1,500 ADT
Heavy 1,500+
Although the volumes on some of these streets are above the
heavy residential classification, the streets remain in the
residential street classification because the threshold traffic
volumes for local residential streets is approximately 2,000
vehicles per day. A through street or collector would have a
normal range of volumes between 2,000 and 5,000 ADT. Arterial
streets have the largest volumes with more than a 5,000 ADT
typically.
During the data collection phase of this study, 9th Street was
closed for construction. This created a situation where through
traffic was physically cut off from using area streets. A good
indicator of the through traffic volumes is the comparison of
traffic volumes on Clark Avenue during and after the closure of
9th Street. The during and after counts were 580 and 1310 vpd,
respectfully, which shows an increase of 730 vehicles per day.
The volume collected indicates a significant percent of the
vehicles represent through traffic, but only three segments
exceed the volume threshold of 2,000 vehicles per day that is a
guideline to separate residential street classification from
collector street classification. This means that the area streets
are not experiencing capacity problems since they are designed to
handle this level of traffic.
5
Traffic Patterns .
The review of traffic patterns for this area consisted of an
origin and destination study which shows that a large number of
motorists are using ,Clark, Kellogg, Burnett, and Douglas Avenues as
through routes . These motorists were observed as beginning and
ending their trips outside the bounded residential areas . Traffic
movements was in the direction of the downtown business district
and hospital areas . The higher volume of "through" traffic was on
Clark, Burnett, and Kellogg Avenues .
Data collection consisted of recording at least 43 trips for each
street segment. Node numbers were used for designating the origins
and destinations points for the trips . The entire neighborhood
was divided into areas north and south of 9th street due to the
difficulting of registering a trip for more than a five block
length. This division of areas and node numbers is shown below.
STREET NODE
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DESIGNATIONS
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CITY OF AMES
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Traffic Department
6
Trips were classified in four general types according to their
points of origins and destinations . These trip classifications are
listed and their descriptions are outlined in the following
paragraphs . The listed types are:
Type 1 . Through Traffic
Type 2 . Residential Traffic
Type 3 . Mixed Traffic
Type 4 . Neighborhood Traffic
Type 1 . Through Traffic
Through traffic is defined as all vehicular trips that had
both origin and destination points outside the neighborhood area.
The schematic which illustrates these trip patterns is shown
below.
NORTH-SOUTH EAST-WEST
THROUGH FLOWS THROUGH FLOWS
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Type 2, Residential traffic
Residential trips are classified as either having origins
and/or destinations points located on that street segment. These
trips serve the residents on that street segment and are generated
by their activites . Shown on the next paged are all the
possiblities for these travel patterns .
7
ti I J RESIDENTIAL
I I RESIDENTIAL
P. TRAFFIC(N-S) - _ ,, „ .. TRAFFIC(E-VV)
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Traffic Department Traffic Department
Type 3 . Mixed traffic
These trips either originate or end outside the neighborhood
and serve other streets located in the neighborhood. These trips
may be through or residential traffic depending on their trip
purpose. Because these trips could not be followed, their purpose
was unknown. Shown are all the possibilities of these trips.
MIXED MIXED
TRAFFIC(N-S) TRAFFIC(E-W)
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Traffic Department Traffic Department
8
Type 4 . Neighborhood traffic
These trips both originate and end on other streets in the
neighborhood. Most likely, these trips are circulatory trips in
the neighborhood. Shown are the possible trip patterns for this
traffic.
NEIGHBORHOOD NEIGHBORHOOD
TRAFFIC(N-S) TRAFFIC(E-W)
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Traffic Department Traffic Department
i
9
Results
Survey results show that the north/south avenues had as much
as 59% through traffic. This was observed on Clark Avenue from
13th Street to 9th Street. Kellogg ; Burnett, and Clark Avenues
had the highest percentage of through traffic in the neighborhoods .
The following table shows the percentage (%) and volume of the
types of traffic along these streets . The north/south streets were
analyzed separately from the east/west avenues due to the different
characteristics of the traffic flow.
North-South Street Traffic
Average Through Residential Mixed Neighborhood
Street Section Daily
Traffic $ Volume 8 Volume 8 Volume 8 Volume
Douglas Ave - 9th-12th 690 11.9 82 10.7 73 38.0 262 39.4 271
Douglas Ave - 6th-9th 1070 28.6 306 34.5 369 32.1 343 4.8 51
Kellogg Ave - 9th-13th 1910 20.0 382 29.4 561 37.6 718 13.0 248
Kellogg Ave - 6th-9th 1860 39.3 730 17.9 332 25.0 465 17.8 331
Burnett Ave - 9th-13th 1050 46.9 492 18.8 197 24.4 256 9.9 103
Burnett Ave - 6th-9th 1010 30.5 308 16.5 166 46.0 464 7.0 70
Clark Ave - 9th-13th 1470 59.4 873 10.2 149 26.0 382 4.4 64
Clark Ave - 6th-9th 2300 36.1 830 21.0 483 32.7 752 10.2 234
Wilson Ave - 9th-13th 500 16.4 82 27.3 136 49.2 246 7.1 35
Wilson Ave - 6th-9th 300 12.5 37 66.7 200 20.8 62 0.0 0
10
The through traffic on these streets was of concern because of
its ' speeds and volumes . The distributed through traffic is
shown on the neighborhood street system diagram inwhich Clark
Avenue has the predominant through flow.
VOLUME-PERCENT
THROUGH TRAFFIC
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11 th Street
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a fi: 16.4% 46 9% 20.OX 11 9%:
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40: 820: 310 730: 310:
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11
As a comparison, the types of traffic volumes were also
observed for the east/west streets in this neighborhood. The
"high" percentage for through traffic was recorded on loth Street
with 3% indicated. The 9th Street traffic was not classified since
it's a designated through street. On these east/west streets, the
predominant flow was residential traffic. . The traffic volumes and
percentages of traffic are shown in this table on the next page.
East-West Street Traffic
Average Through Residential Mixed Neighborhood
Street Section Daily
Traffic 8 Volume 8 Volume 8 Volume $ Volume
12th Street 370 0.0 0 82.4 304 8.8 32 8.8 32
llth Street 1160 0.0 0 52.2 605 14.1 163 33.7 390
loth Street 610 3.0 18 59.0 359 22.0 134 16.0 97
8th Street 690 0.0 0 58.3 402 25.0 172 16.7 115
7th Street 1190 1.2 14 72.6 863 11.9 141 14.3 1 170
12
Hospital/McFarland Clinic Traffic Patterns
An analysis of traffic patterns *to the hospital and McFarland
Clinic indicated that the majority entered the hospital from Duff
on llth Street and from 13th Street on Kellogg Avenue. . There
also was a large number of motorists traveling to and from the
hospital on Kellogg Street from 9th Street.
Two methods were used to collect data for this analysis. First,
the traffic movements were recorded at the hospital/clinic
entrances at the Douglas/llth Street and Kellogg/12th Street
intersections, and also midblock on Kellogg between llth Street and
12th Street. These counts gave the - directions of the. traffic
entering and leaving the hospital/clinic's parking lots. Daily
traffic counts on llth Street at the 100 and 200 block, and on
Kellogg Avenue at the 1200 block were also used to obtain the total
daily volume generated to hospital from the adjacent streets .
Results
The traffic patterns to the hospital were mainly distributed
between motorists traveling north and south bound on Kellogg
Avenue, and motorists westbound on llth Street. The total daily
traffic to the hospital was 2,530 trips inwhich many were
traveling to the McFarland Clinic's parking lot. The daily trips
to the hospital from adjacent streets are illustrated on the next
page.
13
Hospital/McFarland TripPatterns
1 3th Street
704
637
821
Cz
6 g
Q 958
CD Q
O
163 636 0
35 ` 636
159
7 11 th Street 1�* '91
4 159
* *
33 67
597 226
* Traffic volumes to other hospital access points
14
Traffic Speeds
An analysis of motorist's speeds showed that excessive speeds
were measured on north/south avenues . Typical motorist speeds in
residential neighborhoods should not exceed 25 miles per hour.
Residential speed limits are 25 miles per hour on all streets in
these neighborhoods .
Speeds were measured only on north/south avenues . East/west
streets were not included since yield controls forced traffic to
slow at most intersections . Speeds were measured along streets
during at least a 24 hour period using traffic recorder
instruments .
Results
Speeds were highest on Clark and Kellogg Avenues where
averages were above 25 miles per hour. These higher traffic speeds
could be attributed to the high percentage of through traffic.
This traffic maintains a faster speed to travel to destinations
outside, the neighborhood. The average and 85% percentile speeds
are shown on the neighborhood street system diagram on the next
page. The 85% percentile speed indicates the speed inwhich 85% are
travelling at or lower.
15
AVERAGE
SPEEDS
MGFartand
Cirrc
Mary C—eley
Hospital
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Average Speed (mph)
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16
Accidents
Accident data showed that intersections within these
neighborhoods had higher accident rates in comparison with other
residential streets. Accident frequency at each intersection
varied during the years, however, some intersections had
significantly larger accident rates than others.
Accident data was collected during the 1984 to 1990 period by
accessing records from the Iowa Department's ALAS files. This
source is used by both insurance companies and Iowa Department of
Transportation officials for analysis of driver's records and
accident statistics .
Results
The accident analysis showed that many intersections with
yield sign controls were experiencing higher than normal accident
rates. This may be the result of higher speeds and/or. the higher
traffic volumes on the north/south avenues. Approximately 90% of
these 136 accidents were right-angle accidents inwhich driver error
was a contributing factor. Driver error could be attributed to
misjudging speeds along these streets . These accidents included
three pedestrian and one pedacycle mishap.
Accident statistics also show that intersections on Kellogg
had more accidents than on other neighborhood streets. The state
average accident rate is 0.9 accidents per million enter vehicles.
Sixteen intersections of the twenty-seven -either exceeded this rate
or had a relatively similar rate. Accident numbers and rates for a
six year period are shown on the next page.
17
Hospital Area Traffic Accidents by Year
Year Estimated Accident
Street Intersection Daily Rate
1984 1985 1986 1987 1988 1989 1990 Totals Volume (mev)
llth St & Douglas Ave 2 1 3 2300 0.5498
loth St & Douglas Ave 1 1 2 960 0.8781
9th St & Douglas Ave 1 1 2210 0.1907
8th St & Douglas Ave 1 1 1 3 1420 0.8905
7th St & Douglas Ave 1 2 3 2190 0.5774
llth St & Kellogg Ave 1 5 3 5 2 1 17 2650 2.7039
loth St & Kellogg Ave 1 1 1 1 2 4 10 2050 2.0561
9th St & Kellogg Ave 1 3 3 1 8 3020 1.1165
8th St & Kellogg Ave 1 1 2 2 6 2070 1.2217
7th St & Kellogg Ave 5 1 2 3 1 2 14 2840 2.0778
12th St & Burnett Ave 1 1 2 1470 0.5735
11th St & Burnett Ave 1 2 3 1400 0.9032
loth St & Burnett Ave 2 2 1370 0.6153
9th St & Burnett Ave 1 1 2 1 5 2400 0.8781
8th St & Burnett Ave 3 1 2 1 1 8 1430 2.3580
7th St & Burnett Ave 3 1 2 3 1 10 2200 1.9159
12th St & Clark Ave 1 1 2 4 1990 0.8472
llth St & Clark Ave 1 1 1 1 4 1920 0.8781
loth St & Clark Ave 1 1 2 1890 0.4460
9th St & Clark Ave 3 1 1 2 3 10 3200 1.3172
8th St & Clark Ave 1 1 2 1 1 6 2450 1.0322
7th St & Clark Ave 1 1 2 4 3220 0.5236
12th St & Wilson Ave 2 1 3 960 1.3172
llth St & Wilson Ave 1 1 890 0.4736
loth St & Wilson Ave 1 2 1 4 860 1.9604
9th St & Wilson Ave 0 1650 0.0000
8th St & Wilson Ave 1 1 790 0.5335
7th St & Wilson Ave 0 1 1560 0.0000
Totals 29 16 16 26 26 13 10 136
Accident frequency at some intersections indicate that stop
signs would be more applicable for safely controlling traffic.
Warrants based on a FHWA study state that stop controls should be
placed at intersections which had more than three accidents in a
four year period. Intersections with this accident experience that
currently have yield signs are:
llth Street and Kellogg Avenue
8th Street and Kellogg Avenue
7th Street and Kellogg Avenue
8th Street and Burnett Avenue
7th Street and Burnett Avenue
12th Street and Clark Avenue
8th Street and Clark Avenue
loth Street and Wilson Avenue
18
By placing stop signs at these locations , there would be 16
stop controlled intersections in the Old Town Area which has a
total of 27 intersections . Ten intersections would have yield
signs and one intersection would have no control . Intersections
are shown below which either meet warrants for stop control or have
existing stop signs . The bold numbers at the intersections
indicate the number of accidents during this six and one-half year
period.
EXPECTED STOP
1 k
.n�:� �a�. � �i��: .,.. .:!!, .�� I CEMENTS
:;;i�;ixK�..�-...::�:: !�.�. !,, ��,- SIGN PLACEMENTS*
McFarland
Ckvc
•Accidents compiled from January 1984 to May 19W
Mary Greeley 121h Street
Hospital
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CITY OF AM ES
i s 5>nstreet" Traffic Department
19
School Routes
The elementary school children in this neighborhood attend
Roosevelt School . The safe school routes show that children are
traveling mainly on 9th Street, 13th Street, and Grand Avenue to
cross at the Grand Ave/9th Street signalized intersection. These
school routes are shown below.
SCHOOL ROUTES
WFulrid
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Mary(3raeleY ianetr.9
HocpMd
i in a.w
w
w
Portable Stop&
Crossing Guard
Signal&Crossing Guard
-00-Safe School Route
Signalized Intersection
= Stop Sign
® Yield Sign
: . ....... CITY OF AME
city Nd
Traffic Department
20
Bus Routes
Cy-ride bus routes are shown on this page. Routes are only on
Clark Avenue from 6th Street to 9th Street, and on 9th Street from
Clark Avenue to Grand Avenue.
BUS ROUTE
McFwkYW
Mxyare4wey 121e s•.w
4*1
..........:::................:::.................::. ,. •Ih BtrM ..........
.....................
ftse.0 Red Gar-Ride Route
®� ; J. �•' Green Cy-Ride Route
Eel
® Signalized Intersection
® mom.«I : Stop Sign
iai' 9 Yield Sign
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CITY OF AMES
aty Hal
Traffic Department
21
Existing Sign Placements
Currently stop and yield signs are placed on these
neighborhood streets predominantly on the east/west streets .
Except for the signs located on the 9th Street intersections, the
east/west streets have signs placed on them at their intersections
with north/south streets .
The reasons for placing intersection controls to favor the
north/south avenues include evenly distributing the through traffic
on these streets . Existing placement of controls are shown on the
diagram below.
EXISTING
:...............:::::..:.. :.:::.:::.:s:: .:::.:::.:::.:::::.::.: :::::::::::::::.:::.::
S IG NAG E
Maori"
....... ...
...... .....
: .
wn Steot >>
® Signalized Intersection
Stop Sign
® ® Yield Sign
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■C AM ES K S
cry Hal
s 5t, t Traffic Department
22
Conclusions and Recommendations .
The results of this study indicate that traffic conditions
were less than favorable along the north/south avenues. These
streets are experiencing more accidents, higher speeds, and higher
traffic volumes than typically encountered on residential streets.
Factors such as the stop and yield sign placements that favor the
north and south bound traffic, and the residential area's proximaty
to the hospital, downtown business districts, and other. large
traffic generators are contributing to these traffic problems.
These traffic problems can be associated with the amount of
through traffic volumes on these neighborhood streets . Currently a
heavy traffic flow for residential streets is being experienced on
some of these north/south avenues inwhich through traffic
contributes to more than half the volume. Residential streets
should be protected from this through traffic; vehicles traveling
on these streets should have a trip origin or destination in the
area served by them. Through traffic is characterized by higher
speeds. By eliminating this traffic, it's conceiveable that speeds
and accidents can be significantly reduced.
One solution to improving traffic conditions is to impede
the through traffic. Alternate strategies include heavy speed
enforcement, street blockages, and/or modifying the stop/yield sign
placements. The simplest solution is the former alternate, inwhich
sign placements are alternated on the north/south and east/west
streets. There are four alternate sign placement schemes which
were reviewed for this area. These are listed with further
explanation for each.
1. 1st alternate sign placement scheme that has no
north/south through route designations.
2 . 2nd alternate sign placement Scheme that has no
north/south through route designations.
3. Designate Burnett Avenue as a through route and alternate
signs on other neighborhood streets.
4 . Designate Clark Avenue as a through route and alternate
signs on other neighborhood streets.
23
These schemes show two-way stop sign placements at all
intersections where warrants are met and also at the Clark/llth and
Burnett/llth intersections . Stop controls are recommended at
these intersections for reducing accidents in the Old Town
neighborhood.
Accidents experience would be improved by installing stop
controls at these intersections . Even though the Clark/llth and
Burnett/llth intersections do not meet stop control warrants, a
number of accidents have occured at these intersections. Also
these intersections have similar roadway. conditions as the higher
accident locations including traffic volumes, speeds, parking, and
landscaping. It could be assumed that warrants would be met in the
future for stop controls at the Clark/llth and Burnett/llth
intersections. . These stop controls would improve conditions
because the yield controls haven't been effective in reducing
accidents at these intersections . Accident experience is higher
than average rates at these yield controlled intersections
compared with other city intersections. The average accident rate
at other yeild controlled intersections in the city is 1.26
accidents in this six year period, whereas the Old Town
intersections average five accidents. By comparison with the
accident numbers at stop controlled intersections in the
neighborhood, the accident numbers at 8th/Clark (4) and
llth/Douglas (3) intersections are significantly less.
24
Alternate 1 .
This sign placement scheme which would reduce through traffic
flows on north/south avenues consists of placing one more stop
control on Burnett Avenue than on other north/south avenues . Stop
signs placed on these streets would be located at 13th, llth, 9th,
7th, and 6th Street. The other north/south avenues would have
stops placed at 13th, loth, 9th, 8th, and 6th street. The llth and
7th streets would have one more stop typically than the 12th, loth,
and 8th streets . The advantage to this plan is that traffic must
stop at least at every other intersection travelling both east/west
and south/north directions . Shown below is this signing plan.
ALTERNATIVE #1
Le'
SIGNAGE
McF
Cklic rW
Mary Ckeeley .`'' 12th Street
HospU
fiE: :n
ii
N �yNiA.
loy
Mwi MrH
v o
Street E.- -
�X!'r
A 871 Street ."k
y N Ash;
b € a a a
Signalized Intersection
« x 711 Street : Stop Sign
w o Yield Sign
w;r
.. . : :;.x. CITY OF AMES
GlY Hall
Lam i 5,heeto Traffic Department
25
Alternate 2 .
This signing scheme alternate which would reduce through
traffic flows on north/south avenues consists of placing one more
stop control on Clark and Kellogg Avenue than on other north/south
avenues . This strategy would reduce the predominant through flows
on Kellogg and Clark Avenues . The advantage to this scheme is that
through traffic to the hospital is largely impeded by placing stop
signs strategically on Kellogg and Douglas Avenue. It also favors
llth Street flow from Duff to the hospital entrance on Douglas .
Shown below is this signing plan.
3 ALTERNATIVE #2
SIGNAGE
McFarland
Cklic
M� 44? 12th street
M street
y3
':"� « Bth Street
® Signalized Intersection
Y streetis
'. !` w Stop Sign
v Yield Sign
r ::.
s 6 a s street
M! » ! CITY OF AMES
£tiy /y#y HA
"
NI. s sthseeet Traffic Department
26
Alternate 3 .
This signing plan would be implemented if Burnett Avenue would
be designated a through route in the neighborhood. Burnett Avenue
is located mid-point between Grand and Duff Avenue and a three
block spacing is typically used for through routes. The advantage
to this signing plan is that it would reduce greatly the
predominant through traffic on Kellogg and Clark Avenues . This
plan also impedes through traffic flow to the hospital on Kellogg
and Douglas Avenues . Shown below is this plan.
ALTERNATIVE #3
SIGNAGE
McFCklic nC a M� 12tF1 Sleet
.S5g
%rS s8.
�4
}:
9C1 Street '
is X
lob
kA
« M Street
b _ ® Signalized Intersection
« Y MStrom : Stop Sign
® Yield Sign
M street
h
Cily HaA ?�:
CITY OF AMES
Lad 1 1 61s SthSr"t Traffic Department
27
Alternate 4 .
This signing plan would be implemented if Clark Avenue would
be designated a through route. Clark Avenue has the predominant
through traffic to the business districts . The advantage to this
plan is that it would greatly reduce the through flows on the other
neighborhood streets . This plan also impedes through traffic flow
to the hospital on Kellogg and Douglas Avenues . Shown below is
this plan.
ALTERNATIVE #4
! SIGNAGE
aMcFarland
Clinic
Mary Greeley 12th street
Hospital
Mi
y:t{
1100
4e
w
>
•E
e1
s 9tl1 Street
Y 41.":'tee:.' 'i:£i!4'. ::E:x::•s:"..¢:;4 ,;: v;;4E'e': v.!4!Y'Y
iSx4Ex
Y .e;jr
s r
FS Oak
stir:
> e I ii
b ® Signalized Intersection
Y
Stop Sign
o Yield Sign
p
cityHom
« �street
CITY OF AMES
5>1s Traffic Department
28
The recommended signing scheme is alternate #2 This scheme
addresses the additional warranted stop signs placements, and also
the addition of stop sign controls at the Clark/llth and
Burnett/llth intersections . This alternate is preferred over #1
because it emphasizes disruption of the predominant north/south
through movements on Kellogg and Clark Avenue. It also encourages
flow to the hospital and clinic parking lots from Duff Avenue on
llth Street.