RES 2014-05 IMPLEMENTING TRAFFIC STUDY RECOMMENDATIONS AND ACCEPTING FOCUSED TRAFFIC STUDY
City of Bainbridge Island
Traffic Report
Focused Traffic Study
December 11, 2013
505 Fifth Avenue S., Suite 300
Seattle, WA 98104
1.800.615.9900 / 206.436.0515
TABLE OF CONTENTS
1.0 EXECUTIVE SUMMARY ........................................................................................................................................................ 1
2.0 BLAKELY AVENUE NE .......................................................................................................................................................... 3
3.0 NE BUCKLIN HILL ROAD ................................................................................................................................................... 9
4.0 FLETCHER BAY ROAD NE ............................................................................................................................................... 13
5.0 LYNWOOD CENTER ROAD NE ................................................................................................................................... 19
6.0 PHELPS ROAD NE ............................................................................................................................................................... 25
7.0 PLEASANT BEACH DRIVE NE ......................................................................................................................................... 31
8.0 SPORTSMAN CLUB ROAD NE ....................................................................................................................................... 35
9.0 NE NEW BROOKLYN ROAD ......................................................................................................................................... 39
10.0 LYNWOOD CENTER ROAD NE AND NE BAKER HILL ROAD ......................................................................... 43
11.0 MILLER ROAD NE AND NE KOURA ROAD ............................................................................................................. 49
12.0 NE VALLEY ROAD AND SUNRISE DRIVE NE............................................................................................................ 55
13.0 REFERENCES .......................................................................................................................................................................... 61
LIST OF TABLES
TABLE 1-1: SUMMARY OF RECOMMENDATIONS .................................................................................................................................... 1
TABLE 2-1: CHARACTERISTICS SUMMARY BY ZONE FOR BLAKELY AVE NE ...................................................................................... 4
TABLE 2-2: CRASH REPORT SUMMARY FOR BLAKELY AVE NE............................................................................................................ 5
TABLE 2-3: CRASH RATES FOR BLAKELY AVE NE ................................................................................................................................. 5
TABLE 2-4: RADAR SPEED STUDY SUMMARY FOR BLAKELY AVE NE .................................................................................................. 6
TABLE 3-1: CHARACTERISTICS SUMMARY FOR NE BUCKLIN HILL RD ............................................................................................. 10
TABLE 3-2: CRASH REPORT SUMMARY FOR NE BUCKLIN HILL RD.................................................................................................. 11
TABLE 3-3: CRASH RATE FOR NE BUCKLIN HILL RD ......................................................................................................................... 11
TABLE 3-4: RADAR SPEED SURVEY FOR NE BUCKLIN HILL RD ......................................................................................................... 11
TABLE 4-1: CHARACTERISTICS SUMMARY BY ZONE FOR FLETCHER BAY RD NE ........................................................................... 14
TABLE 4-2: CRASH REPORT SUMMARY FOR FLETCHER BAY RD NE................................................................................................. 15
TABLE 4-3: CRASH RATES FOR FLETCHER BAY RD NE ...................................................................................................................... 15
TABLE 4-4: RADAR SPEED STUDY SUMMARY FOR FLETCHER BAY RD NE ....................................................................................... 15
TABLE 5-1: CHARACTERISTICS SUMMARY BY ZONE FOR LYNWOOD CENTER RD NE ................................................................. 20
TABLE 5-2: CRASH REPORT SUMMARY FOR LYNWOOD CENTER RD NE ....................................................................................... 21
TABLE 5-3: CRASH RATES FOR LYNWOOD CENTER RD NE ............................................................................................................ 21
TABLE 5-4: RADAR SPEED STUDY SUMMARY FOR LYNWOOD CENTER RD NE ............................................................................. 22
TABLE 6-1: CHARACTERISTICS SUMMARY BY ZONE FOR PHELPS RD NE ........................................................................................ 26
TABLE 6-2: CRASH REPORT SUMMARY FOR PHELPS RD NE .............................................................................................................. 27
TABLE 6-3: CRASH RATES FOR PHELPS RD NE .................................................................................................................................... 27
TABLE 6-4: RADAR SPEED STUDY SUMMARY FOR PHELPS RD NE .................................................................................................... 28
TABLE 7-1: CHARACTERISTICS SUMMARY FOR PLEASANT BEACH DR NE ...................................................................................... 32
TABLE 7-2: CRASH REPORT SUMMARY FOR PLEASANT BEACH DR NE ........................................................................................... 33
TABLE 7-3: CRASH RATE FOR PLEASANT BEACH DR NE .................................................................................................................. 33
TABLE 7-4: RADAR SPEED STUDY SUMMARY FOR PLEASANT BEACH DR NE ................................................................................. 33
TABLE 8-1: CHARACTERISTICS SUMMARY FOR SPORTSMAN CLUB RD NE ..................................................................................... 36
TABLE 8-2: CRASH REPORT SUMMARY FOR SPORTSMAN CLUB RD NE .......................................................................................... 37
TABLE 8-3: CRASH RATE FOR SPORTSMAN CLUB RD NE ................................................................................................................. 37
TABLE 8-4: RADAR SPEED SURVEY FOR SPORTSMAN CLUB ROAD NE ............................................................................................ 37
TABLE 9-1: CHARACTERISTICS SUMMARY FOR NE NEW BROOKLYN RD AT NORTH TOWN DR NE ....................................... 40
TABLE 9-2: RADAR SPEED SURVEY FOR NE NEW BROOKLYN RD ................................................................................................... 41
TABLE 10-1: CHARACTERISTICS SUMMARY FOR LYNWOOD CENTER RD NE & NE BAKER HILL RD ......................................... 44
TABLE 10-2: CRASH REPORT SUMMARY FOR LYNWOOD CENTER RD NE & NE BAKER HILL RD ............................................. 45
TABLE 10-3: INTERSECTION TURNING MOVEMENTS FOR LYNWOOD CENTER RD NE & NE BAKER HILL RD ........................ 45
TABLE 10-4: SYNCHRO ANALYSIS FOR LYNWOOD CENTER RD NE & NE BAKER HILL RD ........................................................ 45
TABLE 11-1: CHARACTERISTICS SUMMARY FOR THE INTERSECTION OF MILLER RD NE & NE KOURA RD ............................... 50
TABLE 11-2: CRASH REPORT SUMMARY FOR MILLER RD NE & NE KOURA RD ............................................................................ 51
TABLE 11-3: INTERSECTION TURNING MOVEMENTS FOR MILLER RD NE & NE KOURA RD ....................................................... 51
TABLE 11-4: SYNCHRO ANALYSIS FOR MILLER RD NE & NE KOURA RD ...................................................................................... 52
TABLE 12-1: CHARACTERISTICS SUMMARY FOR THE INTERSECTION OF NE VALLEY RD & SUNRISE DR NE ............................. 56
TABLE 12-2: CRASH REPORT SUMMARY FOR NE VALLEY RD & SUNRISE DR NE .......................................................................... 57
TABLE 12-3: INTERSECTION TURNING MOVEMENTS FOR NE VALLEY RD & SUNRISE DR NE ..................................................... 57
TABLE 12-4: RADAR SPEED STUDY SUMMARY FOR NE VALLEY RD ................................................................................................. 57
TABLE 12-5: SYNCHRO ANALYSIS FOR NE VALLEY RD & SUNRISE DR NE .................................................................................... 58
LIST OF FIGURES
FIGURE 2-1: BLAKELY AVE NE CORRIDOR MAP WITH SIGNING .......................................................................................................... 3
FIGURE 2-2: MIDDLE ZONE FACING NORTH .......................................................................................................................................... 4
FIGURE 2-3: SOUTH ZONE FACING SOUTH ............................................................................................................................................ 4
FIGURE 3-1: NE BUCKLIN HILL RD CORRIDOR MAP WITH SIGNING .................................................................................................. 9
FIGURE 3-2: FACING WEST NEAR BLAKELY AVE NE ........................................................................................................................... 10
FIGURE 3-3: FACING EAST NEAR FIRE STATION.................................................................................................................................... 10
FIGURE 3-4: PROPOSED NE BUCKLIN HILL RD SIGNING ................................................................................................................... 12
FIGURE 4-1: FLETCHER BAY RD NE CORRIDOR MAP WITH SIGNING ............................................................................................... 13
FIGURE 4-2: FACING NORTH NEAR NE HIGH SCH. RD ..................................................................................................................... 14
FIGURE 4-3: S. ZONE NEAR LYNWOOD CTR. RD NE ........................................................................................................................ 14
FIGURE 5-1: LYNWOOD CENTER RD NE CORRIDOR MAP WITH SIGNING ..................................................................................... 19
FIGURE 5-2: N. ZONE NEAR FLETCHER BAY RD NE ........................................................................................................................... 20
FIGURE 5-3: S. ZONE AT POINT WHITE DR NE .................................................................................................................................. 20
FIGURE 6-1: PHELPS RD NE CORRIDOR MAP WITH SIGNING............................................................................................................. 25
FIGURE 6-2: N. ZONE NEAR MADISON AVE NE.................................................................................................................................. 26
FIGURE 6-3: GUARDRAIL ALONG WEST SIDE........................................................................................................................................ 26
FIGURE 7-1: PLEASANT BEACH DR NE CORRIDOR MAP WITH SIGNING .......................................................................................... 31
FIGURE 7-2: PLEASANT BEACH DR NE FACING NORTH .................................................................................................................... 32
FIGURE 7-3: PLEASANT BEACH DR NE FACING SOUTH ..................................................................................................................... 32
FIGURE 8-1: SPORTSMAN CLUB RD NE CORRIDOR MAP WITH SIGNING......................................................................................... 35
FIGURE 8-2: FACING SOUTH .................................................................................................................................................................. 36
FIGURE 8-3: FACING NORTH ................................................................................................................................................................. 36
FIGURE 9-1: NE NEW BROOKLYN RD CORRIDOR MAP WITH SIGNING .......................................................................................... 39
FIGURE 9-2: NE NEW BROOKLYN RD AT CROSSWALK ..................................................................................................................... 40
FIGURE 9-3: NE NEW BROOKLYN RD SCHOOL ZONE ...................................................................................................................... 40
FIGURE 9-4: EXAMPLE SIGNING PLAN FOR NE NEW BROOKLYN RD .............................................................................................. 42
FIGURE 10-1: SIGNING AT LYNWOOD CENTER RD NE & NE BAKER HILL RD ............................................................................. 43
FIGURE 10-2: FACING NORTH ............................................................................................................................................................... 44
FIGURE 10-3: FACING WEST ................................................................................................................................................................... 44
FIGURE 10-4: MUTCD TRAFFIC SIGNAL PEAK HOUR WARRANT ..................................................................................................... 46
FIGURE 11-1: SIGNING AT MILLER RD NE & NE KOURA RD ........................................................................................................... 49
FIGURE 11-2: NW CORNER FACING NORTH ...................................................................................................................................... 50
FIGURE 11-3: SW CORNER FACING SOUTH......................................................................................................................................... 50
FIGURE 11-4: MUTCD TRAFFIC SIGNAL PEAK HOUR WARRANT ..................................................................................................... 53
FIGURE 12-1: SIGNING AT NE VALLEY RD & SUNRISE DR NE .......................................................................................................... 55
FIGURE 12-2: WEST APPROACH ............................................................................................................................................................ 56
FIGURE 12-3: INTERSECTION FREIGHT DELIVERY ................................................................................................................................. 56
FIGURE 12-4: MUTCD TRAFFIC SIGNAL PEAK HOUR WARRANT ..................................................................................................... 58
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1.0 EXECUTIVE SUMMARY
A series of engineering studies was conducted for eight segments and three intersections for the City of
Bainbridge Island to determine whether the existing traffic control is adequate given the geometric,
environmental and traffic conditions. In addition to referencing data provided by the City,
measurements were taken and analyzed to determine the appropriate traffic control for each location.
Each section of the report includes a discussion of existing conditions, crash history, and issues that
were identified during the study. The combination of these factors provides the basis for each
recommendation. Table 1-1 is a summary of the recommendations made based on location. Additional
details are documented in the report.
Table 1-1: Summary of Recommendations
Location Study Type Recommendation
Blakely Ave NE Speed Maintain speed limits.
Install speed zone ahead signing.
NE Bucklin Hill Rd Speed Reduce speed limit to 30 mph.
Fletcher Bay Rd NE Speed Maintain speed limits.
Lynwood Center Rd NE Speed
Shift speed zone locations.
Install additional speed limit sign.
Install reduced speed limit ahead sign.
Phelps Rd NE Speed
Maintain speed limits.
Install reduced speed limit ahead sign.
Examine recommended speeds for curves.
Pleasant Beach Dr NE Speed
Reduce speed limit to 20 mph.
Install recommended speed and curve warning
signs.
Sportsman Club Rd NE Speed
Replace existing 30-mph speed sign with a
school zone ahead sign.
Maintain all other speed limit signs.
NE New Brooklyn Rd School Zone Incorporate crosswalk in school zone.
Lynwood Center Rd NE & NE
Baker Hill Rd Intersection
Maintain existing intersection traffic control.
Relocate stop bars on NE Baker Hill Rd.
Install crosswalk signing.
Review crosswalk illumination.
Miller Rd NE & NE Koura Rd Intersection
Maintain existing intersection traffic control.
Remove vegetation to increase intersection sight
distance on west leg.
Install stop ahead sign.
NE Valley Rd & Sunrise Dr NE Intersection
Maintain existing intersection traffic control.
Install marked crosswalks and signing.
Install stop bars.
Install reduced speed limit ahead sign.
Relocate speed limit signs.
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2.0 ENGINEERING AND SPEED SURVEY – BLAKELY AVENUE NE: NE
COUNTRY CLUB ROAD TO NE BUCKLIN HILL ROAD
Blakely Avenue NE is a minor arterial that connects Blakely Harbor to Bucklin Hill Road NE, which leads
to the island’s central downtown area. Blakely Avenue NE runs north-south between NE Bucklin Road
and W Blakely Ave NE. A horizontal curve in the vicinity of Birkland Rd NE changes the alignment to
east-west. Blakely Ave NE has an average daily traffic volume of 3,500 vehicles per day (vpd). The
primary objective for this study was to determine the appropriate speed limits for the corridor between
NE Country Club Rd and NE Bucklin Hill Rd. Figure 2-1 shows the project limits with the posted
regulatory and warning signing along the roadway.
Figure 2-1: Blakely Ave NE corridor map with signing
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2.1 Project Area Description
Figure 2-2: Middle zone facing north Figure 2-3: South zone facing south
Blakely Ave NE has three marked speed zones with slightly varying characteristics. The attributes for
the entire corridor are summarized in Table 2-1.
Table 2-1: Characteristics Summary by Zone for Blakely Ave NE
Item North Speed Zone Middle Speed Zone South Speed Zone
Geometry
Alignment North-south North-south East-west
Lanes (per direction) 1 1 1
Lane Width 11’ 11’ 11’
Shoulder Width 1’ to 2’ 0.5’ 0.5’ to 3’
Horizontal Curves Minor Major near W Blakely
Ave NE
Minor
Vertical Curves Minor Minor Moderate near
Birkland Rd NE
Surrounding Environment
Setting Forested Forested, occasional
open areas
Forested
Roadside Ditches Infrequent Infrequent Infrequent
Driveways Infrequent Multiple for Cpt.
Blakely Elem. School
Infrequent
Pull-Out Areas Not present Not present Multiple (gravel)
Clear Zones Infrequent trees Overgrown vegetation,
infrequent obstacles
Infrequent trees
Curb, Gutter and
Sidewalk
Not present Present only at SW
and SE corners of
intersection with NE
Baker Hill Rd
Not present
Lighting Not present One streetlight at
marked crosswalk
Not present
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Traffic Control
Lane Markings Marked centerline and
edge lines
Marked centerline and
edge lines, marked bike
lanes near Cpt. Blakely
Elem. School
Marked centerline and
edge lines
Speed Limit 40 mph 30 mph 40 mph
Major Intersections Thru at NE Bucklin Hill
Rd
Thru at NE Baker Hill
Rd
Stop at Lynwood
Center Rd NE
Additional Measures None Two traffic islands None
2.2 Crash History
Twelve reported crashes have occurred along this segment from January 1, 2008 to June 30, 2013: six in
the north segment, three in the middle, and three in the south. Each crash is summarized in Table 2-2.
Table 2-2: Crash Report Summary for Blakely Ave NE
Date Time Description
North Speed Zone
05/12/2010 15:54 Intersection collision after driver failed to see other driver before turning
05/23/2010 23:23 Driver travelling greater than 50 mph left roadway, hit ditch and re-entered
06/03/2010 19:01 Driver lost control of vehicle due to seeing coyote
07/24/2010 11:25 Driver struck deer which jumped in front of vehicle
05/24/2011 13:10 Collision after one driver fell asleep at the wheel
06/08/2011 13:50 Driver left road, hit tree and landed on side due to deer running into road
Middle Speed Zone
08/23/2008 13:27 Driver turning left was rear ended by a driver talking on a cell phone
12/19/2009 00:00 Driver struck a suddenly-appearing deer
01/04/2012 14:30 Vehicle turned into school parking lot and scraped a parked car
South Speed Zone
01/29/2010 23:39 Inattentive driver struck fire hydrant
11/24/2012 21:42 Driver drifted off road into utility pole
06/22/2013 00:00 Driver drifted off road into ditch, overcorrected, crossed road, stuck tree
The crash rate for each speed zone was calculated based on the number of reported crashes, daily
traffic volumes, segment length, and crash history duration. Table 2-3 summarizes the crash rates for
Blakely Ave NE, with a comparison to county and statewide averages.
Table 2-3: Crash Rates for Blakely Ave NE
Location Crashes
Average
Daily Traffic
(vpd)
Study
Length
(miles)
Crash
History
(months)
Crashes per
Million
Veh-Miles
Blakely Ave NE 12 3,500 2.23 66 0.77
North Speed Zone 6 3,500 0.87 66 0.98
Middle Speed Zone 3 3,500 0.71 66 0.61
South Speed Zone 3 3,500 0.65 66 0.66
Kitsap County1 - - - - 1.72
Washington State2 - - - - 2.57
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All three segments individually, as well as the corridor as a whole, have crash rates lower than the
average for Kitsap County. The Federal Highway Administration (FHWA) recommends reducing speed
limits if crash rates exceed the statewide average. The average crash rate for urban minor arterial state
routes in Washington State is 2.57 crashes per million vehicle miles. No portion of Blakely Ave NE
exceeds this crash rate. Therefore, the speed limits should not be reduced because of crash history.
2.3 Speed Survey
A radar speed survey was conducted on August 22, 2013 for all three segments. The weather was
sunny, dry, and clear. Table 2-4 is a summary of these studies. Traffic was light, with virtually no
platoons and a random flow rate.
Table 2-4: Radar Speed Study Summary for Blakely Ave NE
Location Sample
Size
Speed
Limit
(mph)
Mean
Speed
(mph)
10-mph
Pace
Percent
Within
Pace
85th
Percentile
Speed (mph)
North Speed Zone
(1500’ N of NE Baker Hill Rd) 99 40 40.7 36 to 46 90% 44.0
Middle Speed Zone
(1000’ S of NE Baker Hill Rd) 81 30 33.0 28 to 38 89% 37.0
South Speed Zone
(800’ W of NE Oddfellows Rd) 66 40 40.4 35 to 45 86% 44.0
North Speed Zone
The speed survey for the north speed zone reveals a high (90%) number of vehicles within the 10-mph
pace speed, indicating a consistent flow speed.
The 85th percentile of 44.0 mph means that the posted speed limit of 40 mph may be too low for this
segment. Established protocol suggests setting a speed limit so that at least 85% of drivers are within
compliance. In this case, that would mean setting the speed limit at 45 mph. However, the difference
between the current statutory speed limit and the 85th percentile speed is not extreme. Considering the
low crash history and consistent driver speeds, it would be reasonable to maintain the current speed
limit in this zone. Assuming no change in driver behavior, increasing the speed limit would decrease the
percentage of drivers exceeding the speed limit from 59% (at 40 mph) to 6% (at 45 mph).
Middle Speed Zone
The speed survey for the middle speed zone reveals a high (89%) number of vehicles within the 10-mph
pace speed, indicating a consistent flow speed.
The 85th percentile of 37.0 mph means that the currently posted speed limit of 30 mph is being deviated
from by a majority of the vehicles on the roadway segment. With this sample, a lower posted speed
limit would increase the percentage of drivers exceeding the posted limit from 75% (at 30 mph) to 99%
(at 25 mph).
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South Speed Zone
The speed survey for the south speed zone reveals a high (86%) number of vehicles within the 10-mph
pace speed, indicating a consistent flow speed.
The 85th percentile of 44.0 mph means that the posted speed limit of 40 mph may be too low for this
segment. Established protocol suggests setting a speed limit so that at least 85% of drivers are within
compliance. In this case, that would mean setting the speed limit at 45 mph. However, the difference
between the current statutory speed limit and the 85th percentile speed is not extreme. Considering the
low crash history and consistent driver speeds, it would be reasonable to maintain the current speed
limit in this zone. Assuming no change in driver behavior, increasing the speed limit would decrease the
percentage of drivers exceeding the speed limit from 52% (at 40 mph) to 11% (at 45 mph).
2.4 Issues and Candidate Mitigation
Wild Animals – Four of twelve crash reports for this corridor cite wild animals as the primary cause.
Animal-based crashes can be severe as drivers may swerve quickly to avoid the animal and lose control
of the vehicle, exit the roadway, or strike a road user. Currently, there are no warning signs highlighting
the presence of animals in the area. The WSDOT Traffic Manual recommends that one of the following
criteria be met prior to installation of a deer crossing sign:
(1) Minimum of 5 documented deer/vehicle collisions per mile per year for at least two of the
past 10 years
(2) Minimum of 10 carcass counts per mile per year for at least three of the past 10 years
(3) Concurrence from region maintenance personnel
This analysis was only able to evaluate criterion (1) based on available information. There have been
four collisions involving wildlife, and three related to deer, since 2008. This criterion is not met and,
therefore, wildlife warning signs are not recommended.
Illumination – This corridor has no continuous illumination, which is consistent with rural areas
throughout Bainbridge Island. There is illumination at the crosswalk at NE Baker Hill Rd. A lack of
illumination can lead to drivers being unable to see their surroundings, including traffic control devices
such as signs or obstacles such as animals that must be avoided. Because the City of Bainbridge Island
does not have any warrants for illumination, this analysis used WSDOT warrants. Illumination is
warranted along roadways of this type if the segment is classified as commercial and either the nighttime
level of service is D or the nighttime crash warrant is satisfied. This roadway segment is not classified as
commercial and, therefore, does not meet illumination warrants.
Bicycle Facilities – Multiple cyclists were observed during the radar speed study. The City of Bainbridge
Island’s Non-Motorized Transportation Plan (2008 revision) recommends bike lanes on both sides of
Blakely Ave NE. The addition of bike lanes in this corridor would provide an increase in bicyclist safety.
Speed – Throughout the corridor, the 85th percentile speeds exceed the posted speed limit. The crash
rate, which is below the average county and state rates, and a review of the collision descriptions do not
indicate that current speed limits need to be modified. The difference between measured 85th
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percentile speed and the posted speed limit in the north and south speed zones is less than 5 mph . The
difference in the middle zone is 7 mph. This could be indicative of drivers that are unaware of the speed
limit change.
Signing – Some signing in the corridor is not consistent with current Manual on Uniform Traffic Control
Devices (MUTCD) standards. When the current W6-1 signs at each end of the median islands near
Captain Blakely Elementary School reach the end of their functional life, they should be replaced by
standard R4-7 signs3. Type 1 or Type 3 object markers should also be installed for increased visibility4.
W3-5 or W3-5a signs should be installed in the southbound direction just north of the middle speed
zone and in the northbound direction just south of the middle speed zone to inform drivers that they
need to reduce their speed by at least 10 mph5.
W6-1 R4-7 W3-5 Type 1 Type 3
2.5 Recommendation
The following is recommended for the Blakely Avenue NE corridor:
1. Maintain current speed limits and zones.
2. Replace existing W6-1 signs located in the median islands near Captain Blakely Elementary
School at the end of their functional life with standard R4-7 signs and Type 1 object markers per
the MUTCD.
3. Install reduced speed limit ahead warning signs (W3-5 and W3-5a) for both north and
southbound traffic prior to entering the middle speed zone.
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3.0 ENGINEERING AND SPEED SURVEY – NE BUCKLIN HILL ROAD:
LYNWOOD CENTER ROAD NE TO BLAKELY AVENUE NE
NE Bucklin Hill Road is a minor arterial that connects Fletcher Bay Road NE, Lynwood Center Road
NE, and Blakely Avenue NE to Eagle Harbor Drive NE. NE Bucklin Hill Rd has an average daily traffic of
2,800 vpd. The primary objective for this study was to determine the appropriate speed limits for the
corridor between Lynwood Center Rd NE and Blakely Ave NE. Figure 3-1 shows the project limits
with the posted regulatory and warning signing along the roadway.
Figure 3-1: NE Bucklin Hill Rd corridor map with signing
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3.1 Project Area Description
Figure 3-2: Facing west near Blakely Ave NE Figure 3-3: Facing east near fire station
NE Bucklin Hill Rd has the characteristic listed in Table 3-1.
Table 3-1: Characteristics Summary for NE Bucklin Hill Rd
Item NE Bucklin Hill Rd
Geometry
Alignment East-west
Lanes (per direction) 1
Lane Width 11’
Shoulder Width 0 to 1’
Horizontal Curves None
Vertical Curves None
Surrounding Environment
Setting Mix of forested and clear
Roadside Ditches Frequent
Private Driveways Frequent
Pull-Out Areas Not present
Clear Zones Clear
Curb, Gutter and Sidewalk Not present
Lighting Street lights present near school and fire station
Traffic Control
Lane Markings Marked centerline and edge lines
Speed Limit 35 mph (see below)
Major Intersections Stop at Blakely Ave NE, thru transition at Lynwood Center Rd NE
3.2 Crash Analysis
Three reported crashes have occurred along this segment from January 1, 2008 to June 30, 2013. Each
crash is summarized in Table 3-2.
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Table 3-2: Crash Report Summary for NE Bucklin Hill Rd
Date Time Description
04/24/2009 18:46 Driver drifted into opposing lane after taking curve at high speed; sideswipe
11/24/2009 21:47 Driver spun out and fishtailed into ditch after turning
01/20/2011 17:15 Driver hit oncoming driver after crossing center line
The crash rate for the corridor was calculated based on the number of reported crashes, daily traffic
volumes, segment length, and crash history duration. Table 3-3 summarizes the crash rate for NE
Bucklin Hill Rd, with a comparison to county and statewide averages.
Table 3-3: Crash Rate for NE Bucklin Hill Rd
Location Crashes
Average
Daily Traffic
(vpd)
Study
Length
(miles)
Crash
History
(months)
Crashes per
Million
Veh-Miles
NE Bucklin Hill Rd 3 2,800 0.17 66 3.13
Kitsap County1 - - - - 1.72
Washington State2 - - - - 2.57
The corridor has a higher crash rate than the Kitsap County average. FHWA recommends reducing
speed limits if crash rates exceed the statewide average. The average crash rate for urban minor arterial
state routes in Washington State is 2.57 crashes per million vehicle miles. NE Bucklin Hill Rd does
exceed this crash rate. Therefore, it may be warranted to reduce the speed limit due to crash history.
3.3 Speed Survey
A radar speed survey was taken on November 4, 2013. The weather was partly sunny and dry. Table
3-4 is a summary of this study. Traffic was light, with virtually no platoons and a random flow rate.
Table 3-4: Radar Speed Survey for NE Bucklin Hill Rd
Location Sample
Size
Speed
Limit
(mph)
Mean
Speed
(mph)
10-mph
Pace
Percent
Within
Pace
85th
Percentile
Speed (mph)
NE Bucklin Hill Rd 94 35 31.4 27 to 37 90% 35.8
The speed survey reveals a high (90%) numbers of vehicles within the 10-mph pace speed, indicating a
consistent flow speed.
The 85th percentile of 35.8 mph means that the currently posted speed limit of 35 mph is being followed
by a majority of the vehicles on the roadway segment. Speed zoning theory best practices recommend
that the 85th percentile speed be captured below the posted speed limit in most cases, suggesting that
the speed limit should be increased to 40 mph. However, the difference between the posted speed limit
and the 85th percentile speed is minimal. With this sample, a lower posted speed limit would increase
the percentage of drivers exceeding the posted limit from 15% (at 35 mph) to 53% (at 30 mph).
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3.4 Issues and Candidate Mitigation
Speed – In the current 35-mph speed zone, the 85th percentile speed closely matches the posted speed
limit. The crash rate in the corridor exceeds both the Kitsap County and WA State averages.
However, an analysis of the crash rate reveals that only two of the reported crashes involved multiple
vehicles, the other was a driver who fishtailed. Both of the remaining crashes were sideswipes in which
one driver crossed the double-yellow centerline. This type of collision suggests that speed alone may
not be the reason behind the issue of optimal safety in this segment. There are other factors to
consider; limited roadway width, a school / pedestrian environment, significant bicycle presence and a
lack of segregated non-motorized facilities should be taken into consideration. The City’s Non-
Motorized Transportation Plan calls for bike lanes on either side of NE Bucklin Hill Rd. Once installed,
these lanes will allow for emergency maneuver room which should reduce the likelihood of future
crashes due to vehicles crossing the centerline. In the interim, a reduction in posted speed limit may
alter driver behavior in the segment to reduce the potential for traffic accident.
3.5 Recommendation
The following is recommended for the NE Bucklin Hill Rd corridor:
1. Reduce the posted speed limit in this segment of the corridor from the existing 35 mph to 30
mph until planned roadway improvements to provide segregated non-motorized facilities are in
place. Figure 3-4 provides a possible signing configuration for the segment.
Figure 3-4: Proposed NE Bucklin Hill Rd signing
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4.0 ENGINEERING AND SPEED SURVEY – FLETCHER BAY ROAD NE:
LYNWOOD CENTER ROAD NE TO NE HIGH SCHOOL ROAD
Fletcher Bay Road NE is a minor arterial that connects Lynwood Center Road NE to NE High School
Road and Miller Road NE. Fletcher Bay Rd NE has an average daily traffic of 5,000 vpd. The primary
objective for this study was to determine the appropriate speed limits for the corridor between
Lynwood Center Rd NE and NE High School Rd. Figure 4-1 shows the project limits with the posted
regulatory and warning signing along the roadway.
Figure 4-1: Fletcher Bay Rd NE corridor map with signing
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4.1 Project Area Description
Figure 4-2: Facing north near NE High Sch. Rd Figure 4-3: S. zone near Lynwood Ctr. Rd NE
Fletcher Bay Rd NE has two marked speed zones with slightly varying characteristics. The attributes for
the entire corridor are summarized in Table 4-1.
Table 4-1: Characteristics Summary by Zone for Fletcher Bay Rd NE
Item North Speed Zone South Speed Zone
Geometry
Alignment North-south North-south
No. of Lanes (per direction) 1 1
Lane Width 12’ 12’
Shoulder Width 0.5’ to 3’ 0.5’ to 3’
Horizontal Curves Multiple, large Major near Lynwood Ctr Rd NE
Vertical Curves Minor Minor
Surrounding Environment
Setting Forested Forested
Roadside Ditches Infrequent Infrequent
Private Driveways Infrequent Infrequent
Pull-Out Areas Not present Multiple, gravel
Clear Zones Infrequent trees Infrequent trees
Curb, Gutter and Sidewalk Not present Not present
Lighting Not present Not present
Traffic Control
Lane Markings Marked centerline and edge lines Marked centerline and edge lines
Speed Limit 35 mph 40 mph
Major Intersections Thru at NE High School Rd Stop at Lynwood Center Rd NE
4.2 Crash History
Two reported crashes have occurred along this segment from January 1, 2008 to June 30, 2013. Both of
these crashes occurred in the north speed zone. Each crash is summarized in Table 4-2.
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Table 4-2: Crash Report Summary for Fletcher Bay Rd NE
Date Time Description
North Speed Zone
03/14/2008 20:48 Driver crossed road centerline and struck oncoming vehicle
12/30/2008 06:00 Vehicle left roadway and rolled, due to icy conditions
The crash rate for each speed zone was calculated based on the number of reported crashes, daily
traffic volumes, segment length, and crash history duration. Table 4-3 summarizes the crash rates for
Fletcher Bay Rd NE, with a comparison to county and statewide averages.
Table 4-3: Crash Rates for Fletcher Bay Rd NE
Location Crashes
Average
Daily Traffic
(vpd)
Study
Length
(miles)
Crash
History
(months)
Crashes per
Million
Veh-Miles
Fletcher Bay Rd NE 2 5,000 1.35 66 0.15
North Speed Zone 2 5,000 0.55 66 0.36
South Speed Zone 0 5,000 0.80 66 0.00
Kitsap County1 - - - - 1.72
Washington State2 - - - - 2.57
Both segments individually, as well as the corridor as a whole, have crash rates lower than the average
for Kitsap County. FHWA recommends reducing speed limits if crash rates exceed the statewide
average. The average crash rate for urban minor arterial state routes in Washington State is 2.57
crashes per million vehicle miles. No portion of Fletcher Bay Rd NE exceeds this crash rate. Therefore,
the speed limits should not be reduced because of crash history.
4.3 Speed Survey
A radar speed survey was conducted on August 22, 2013 for both segments. The weather was sunny,
dry, and clear. Table 4-4 is a summary of these studies. Traffic was light, with virtually no platoons and
a random flow rate.
Table 4-4: Radar Speed Study Summary for Fletcher Bay Rd NE
Location Sample
Size
Speed
Limit
(mph)
Mean
Speed
(mph)
10-mph
Pace
Percent
Within
Pace
85th
Percentile
Speed (mph)
North Speed Zone
(550’ S of NE High School Rd) 84 35 34.8 29 to 39 95% 38.0
South Speed Zone
(800’ N of NE Bucklin Hill Rd) 96 40 39.0 36 to 46 88% 42.5
North Speed Zone
The speed survey for the north speed zone reveals a high (95%) number of vehicles within the 10-mph
pace speed, indicating a consistent flow speed.
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The 85th percentile of 38.0 mph means that the currently posted speed limit of 35 mph is being followed
by a majority of the vehicles on the roadway segment. Established protocol suggests setting a speed
limit so that at least 85% of drivers are within compliance. In this case, that would m ean setting the
speed limit at 45 mph. However, the difference between the current statutory speed limit and the 85 th
percentile speed is not extreme. Considering the low crash history and consistent driver speeds, it
would be reasonable to maintain the current speed limit in this zone. Assuming no change in driver
behavior, lowering the posted speed limit would increase the percentage of drivers exceeding the
posted limit from 45% (at 35 mph) to 90% (at 30 mph).
South Speed Zone
The speed survey for the south speed zone also reveals a high (88%) number of vehicles within the 10 -
mph pace speed, indicating a consistent flow speed.
The 85th percentile of 42.5 mph means that the currently posted speed limit of 40 mph is being followed
by a majority of the vehicles on the roadway segment. Established protocol suggests setting a speed
limit so that at least 85% of drivers are within compliance. In this case, that would mean setting the
speed limit at 45 mph. However, the difference between the current statuto ry speed limit and the 85th
percentile speed is not extreme. Considering the low crash history and consistent driver speeds, it
would be reasonable to maintain the current speed limit in this zone. Assuming no change in driver
behavior, lowering the posted speed limit would increase the percentage of drivers exceeding the
posted limit from 33% (at 40 mph) to 87% (at 35 mph).
4.4 Issues and Candidate Mitigation
Speed – Throughout the corridor, the 85th percentile speeds exceed the posted speed limit. The c rash
rate, however, does not suggest that current speed limits need to be reduced. Because the speed
differences are not extreme and the crash rate is low, the speed limits for Fletcher Bay Rd NE are
appropriate.
Illumination – This corridor has no continuous illumination, which is consistent with rural areas
throughout Bainbridge Island. A lack of illumination can lead to drivers being unable to see their
surroundings, including traffic control devices such as signs or obstacles such as animals that must be
avoided. Because the City of Bainbridge Island does not have any warrants for illumination, this analysis
used WSDOT warrants. Illumination is warranted along roadways of this type if the segment is
classified as commercial and either the nighttime level of service is D or the nighttime crash warrant is
satisfied. This roadway segment is not classified as commercial and, therefore, does not meet
illumination warrants.
Bicycle Facilities – Multiple cyclists were observed during the speed study. The City of Bainbridge
Island’s Non-Motorized Transportation Plan (2008 revision) recommends shoulder bike lanes on both
sides of Fletcher Bay Rd NE. The addition of bike lanes in this corridor would provide an increase in
bicyclist safety.
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4.5 Recommendation
The following is recommended for the Fletcher Bay Rd NE corridor:
1. Maintain current speed limits and zones.
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5.0 ENGINEERING AND SPEED SURVEY – LYNWOOD CENTER ROAD NE:
POINT WHITE DRIVE NE TO NE BUCKLIN HILL ROAD
Lynwood Center Road NE is a minor arterial that connects the middle of Bainbridge Island to the
Lynwood Center commercial district. Lynwood Center Rd NE has an average daily traffic volume of
3,850 vpd. The primary objective for this study was to determine the appropriate speed limits for the
corridor between Point White Drive NE and NE Bucklin Hill Road. Figure 5-1 shows the project limits
with the posted regulatory and warning signing along the roadway.
Figure 5-1: Lynwood Center Rd NE corridor map with signing
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5.1 Project Area Description
Figure 5-2: N. zone near Fletcher Bay Rd NE Figure 5-3: S. zone at Point White Dr NE
Lynwood Center Rd NE has two marked speed zones with varying characteristics. The attributes for
the entire corridor are summarized in Table 5-1. The intersection with Baker Hill Rd is discussed in
depth in Chapter 10 of this report.
Table 5-1: Characteristics Summary by Zone for Lynwood Center Rd NE
Item North Speed Zone South Speed Zone
Geometry
Alignment North-south North-south
No. of Lanes (per direction) 1 1
Lane Width 11’ 11’
Shoulder Width 1’ (SB) and 3’ (NB) 0.5’ to 3’
Horizontal Curves Major near NE Bucklin Hill Rd Minor
Vertical Curves Minor Minor
Surrounding Environment
Setting Forested Commercial
Roadside Ditches Infrequent Infrequent
Private Driveways Infrequent Infrequent
Pull-Out Areas Multiple, gravel Multiple, gravel
Clear Zones Frequent obstacles, occasionally
encroaching vegetation
Infrequent trees
Curb, Gutter and Sidewalk Not present Present, both sides
Lighting Not present Present
Parking Not present Present, angled and straight
Traffic Control
Lane Markings Marked centerline and edge lines Marked centerline and edge
lines, 4’ bike lanes on either side
Speed Limit 35 mph 25 mph
Major Intersections Thru at NE Baker Hill Rd and
NE Bucklin Hill Rd
Stop at Lynwood Center Rd NE
Additional Measures Marked crosswalk at south leg of
NE Baker Hill Rd intersection
Multiple marked crosswalks
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5.2 Crash History
Eleven reported crashes have occurred along this segment from January 1, 2008 to June 30, 2013. Of
these, nine have occurred in the north segment and two in the south segment. Each crash is
summarized in Table 5-2.
Table 5-2: Crash Report Summary for Lynwood Center Rd NE
Date Time Description
North Speed Zone
01/23/2008 08:50 Driver turned on to Lynwood Center Rd NE and lost control due to ice
08/08/2008 21:14 Driver struck deer
01/27/2009 Driver slid on wet/snowy pavement, vehicle flipped and landed on its top
12/12/2008 16:09 Tree limb fell on vehicle
05/07/2009 15:25 Driver crossed centerline, struck two vehicles, sending one over a steep
embankment
06/30/2010 00:38 Cyclist lost control and slid off shoulder into ravine
07/31/2010 11:00 Single car rollover, found abandoned
03/28/2012 23:05 Driver took corner too fast, overcorrected and went into ditch
03/20/2013 02:30 Driver unable to negotiate curve on wet roadway
South Speed Zone
10/23/2008 22:26 Bicyclist struck pedestrian
05/24/2010 12:00 Driver backed out of parking space into another parked vehicle
The crash rate for each speed zone was calculated based on the number of reported crashes, daily
traffic volumes, segment length, and crash history duration. Table 5-3 summarizes the crash rates for
Lynwood Center Rd NE, with a comparison to county and statewide averages.
Table 5-3: Crash Rates for Lynwood Center Rd NE
Location Crashes
Average
Daily Traffic
(vpd)
Study
Length
(miles)
Crash
History
(months)
Crashes per
Million
Veh-Miles
Lynwood Center Rd NE 11 3,850 1.30 66 1.12
North Speed Zone 9 3,850 1.15 66 1.00
South Speed Zone 2 3,850 0.15 66 2.24
Kitsap County1 - - - - 1.72
Washington State2 - - - - 2.57
The north speed zone and corridor as a whole have crash rates below the Kitsap County average. The
south section has a higher crash rate though it has seen much fewer crashes since 2008 due primarily to
segment length. A review of the two crashes in this segment indicates that speed may only be a factor
in the bicycle-pedestrian crash. Removal of the parking vehicle collision results in a crash rate of 1.12,
which is lower than the county rate. FHWA recommends reducing speed limits if crash rates exceed
the statewide average. The average crash rate for urban minor arterial state routes in Washington State
is 2.57 crashes per million vehicle miles. No portion of Lynwood Center Rd NE exceeds this crash rate.
Based on this and a review of the crash descriptions , the speed limits should not be reduced because of
crash history.
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5.3 Speed Survey
A radar speed survey was conducted on August 22, 2013 for the north segment and September 19,
2013 for the south segment. On each day, the weather was sunny, dry, and clear. Table 5-4 is a
summary of this study. Traffic was light, with virtually no platoons and a random flow rate.
Table 5-4: Radar Speed Study Summary for Lynwood Center Rd NE
Location Sample
Size
Speed
Limit
(mph)
Mean
Speed
(mph)
10-mph
Pace
Percent
Within
Pace
85th
Percentile
Speed (mph)
North Speed Zone
(½ mi N of NE Baker Hill Rd) 93 35 38.2 34 to 44 88% 41.9
South Speed Zone
(Near Woodson Lane NE) 107 25 26.4 22 to 32 84% 31.0
North Speed Zone
The speed survey for the north speed zone reveals a high (88%) number of vehicles within the 10-mph
pace speed, indicating a consistent flow speed.
The 85th percentile of 41.9 mph means that the currently posted speed limit of 35 mph is being deviated
from by a high number of drivers. Established protocol suggests setting a speed limit so that at least
85% of drivers are within compliance. In this case, that would mean setting the spee d limit at 45 mph.
However, based on the crash history, which includes several incidents involving drivers losing control on
large curves, raising the speed limit is not recommended. Lowering the speed limit does not tend to
increase compliance with the posted speed limit, though it would likely lower average travel speeds.
Assuming no change in driver behavior, lowering the posted speed limit would increase the percentage
of drivers exceeding the posted limit from 80% (at 35 mph) to 98% (at 30 mph).
South Speed Zone
The speed survey for the north speed zone reveals a high (84%) number of vehicles within the 10-mph
pace speed, indicating a consistent flow speed.
The 85th percentile of 31.0 mph means that the currently posted speed limit of 25 mph is being deviated
from by a high number of drivers. Established protocol suggests setting a speed limit so that at least
85% of drivers are within compliance. In this case, that would mean setting the spe ed limit at 35 mph.
However, based on the commercial nature of the area and high pedestrian volumes, it is not
recommended to raise the speed limit. Doing so would reduce the percentage of drivers exceeding the
posted limit from 55% (at 25 mph) to 16% (at 30 mph). Lowering the speed limit does not tend to
increase compliance with the posted speed limit, though it would likely lower average travel speeds.
Assuming no change in driver behavior, lowering the posted speed limit would increase the percentage
of drivers exceeding the posted limit from 55% (at 25 mph) to 94% (at 20 mph).
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5.4 Issues and Candidate Mitigation
Speed – Throughout the corridor, the 85th percentile speeds exceed the posted speed limit. In the
north speed zone, excessive speeds may be contributing to an increased crash rate because of drivers
losing control on the large curve between Fletcher Bay Rd NE and NE Baker Hill Rd, so an increased
speed limit is not recommended. Conversely, the north speed zone crash rate is still below county and
statewide averages, so a reduced speed is not recommended. To improve compliance in the north
speed zone, additional speed limit signs should be installed to inform drivers of the appropriate speed.
This treatment should be monitored to gauge if compliance increases. In the
commercial area, the current speed limit of 25 mph is consistent with similar areas
on the island. The crash history and high pedestrian volumes suggest that the
speed is appropriate. To improve compliance as drivers enter the speed zone
from the north, a W3-5 (reduced speed limit ahead) sign should be installed
before drivers enter the 25-mph speed zone. Northbound traffic through the
south zone is adequately controlled by stop signs and crosswalks and slightly
higher speeds beyond the commercial area do not pose a safety threat.
Speed Zone Limits – The speed limits at the intersection with NE Baker Hill Rd are not consistent:
southbound traffic is operating under a 35-mph speed limit while northbound traffic is in a 25-mph zone.
Speed zones should be consistent whenever possible to improve driver expectations. Because the
intersection of Lynwood Center Rd NE and NE Baker Hill Rd has a marked pedestrian crosswalk across
the south leg with a bus stop at the southeast corner, and the surrounding environment changes
abruptly between commercial and rural at the intersection, the posted speed limit should match the
lower of the two values. In the northbound direction, the current 35-mph speed limit sign should
remain in place. In the southbound direction, the 25-mph speed limit sign should be moved to match
the opposing speed limit sign.
Illumination – This north speed zone has no illumination, which is consistent with rural areas throughout
Bainbridge Island. A lack of illumination can lead to drivers being unable to see their surroundings,
including traffic control devices such as signs or obstacles such as animals that must be avoided. Because
the City of Bainbridge Island does not have any warrants for illumination, this analysis used WSDOT
warrants. Illumination is warranted along roadways of this type if the segment is classified as commercial
and either the nighttime level of service is D or the nighttime crash warrant is satisfied. This north
speed zone segment is not classified as commercial and, therefore, does not meet illumination warrants.
Bicycle Facilities – Multiple cyclists were observed during the radar speed study. The City of Bainbridge
Island’s Non-Motorized Transportation Plan (2008 revision) recommends bike lanes on both sides of
Lynwood Center Rd NE. The addition of bike lanes in this corridor would provide an increase in
bicyclist safety.
W3-5
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5.5 Recommendation
The following is recommended for the Lynwood Center Rd NE corridor:
1. Make the speed limits near NE Baker Hill Rd consistent by moving the existing 25-mph speed
limit sign to be in-line with the existing 35-mph speed limit sign in the northbound direction
north of the intersection.
2. Add one additional 35-mph speed limit sign in the north speed zone in the southbound
direction, prior to entering the large horizontal curve.
3. Install a reduced speed limit ahead (W3-5) sign prior to the relocated 25-mph speed sign for
southbound traffic. Monitor effectiveness of treatment.
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6.0 ENGINEERING AND SPEED SURVEY – PHELPS ROAD NE: NE DAY
ROAD TO MADISON AVENUE NE
Phelps Road NE is a minor arterial that connects the Port Madison area to SR-305. Phelps Rd NE has an
average daily traffic volume of 1,350 vpd. The primary objective for this study was to determine the
appropriate speed limits for the corridor between NE Day Road and Madison Avenue NE. Figure 6-1
shows the project limits with the posted regulatory and warning signing along the roadway.
Figure 6-1: Phelps Rd NE corridor map with signing
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6.1 Project Area Description
Figure 6-2: N. zone near Madison Ave NE Figure 6-3: Guardrail along west side
Phelps Road NE has two marked speed zones with varying characteristics. The attributes for the entire
corridor are summarized in Table 6-1.
Table 6-1: Characteristics Summary by Zone for Phelps Rd NE
Item North Speed Zone South Speed Zone
Geometry
Alignment North-south North-south
No. of Lanes (per direction) 1 1
Lane Width 11’ 11’
Shoulder Width 0.5’ north of NE Hidden Cove
Rd, 4’ to 6’ (SB only) south of
NE Hidden Cove Rd
0.5’ (NB), 4’ to 6’ (SB)
Horizontal Curves Minor Major near fire station
Vertical Curves Minor Minor
Surrounding Environment
Setting Forested Forested
Roadside Ditches Continuous along east side Infrequent
Private Driveways Frequent Infrequent
Pull-Out Areas Multiple (gravel) Multiple (gravel)
Clear Zones Infrequent obstacles, occasionally
encroaching vegetation
Infrequent obstacles, occasionally
encroaching vegetation
Curb, Gutter and Sidewalk Not present Not present
Lighting Not present Not present
Guardrails Two (150’ each) along west side Not present
Traffic Control
Lane Markings Marked centerline and edge lines Marked centerline and edge lines
Speed Limit 40 mph 30 mph
Major Intersections Stop at Madison Ave NE Stop at NE Day Rd
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6.2 Crash History
Six reported crashes have occurred along this segment from January 1, 2008 to June 30, 2013. Of these,
five have occurred in the north segment and one in the south segment. Each crash is summarized in
Table 6-2.
Table 6-2: Crash Report Summary for Phelps Rd NE
Date Time Description
North Speed Zone
03/17/2008 18:07 Driver swerved to miss cat, left roadway and hit two mailboxes
01/10/2009 16:44 Driver took eyes off road and ran off shoulder
04/29/2010 21:27 Driver struck deer that jumped into roadway
09/05/2010 01:30 Driver crashed into fence and abandoned vehicle
05/05/2011 08:27 Driver fell asleep at wheel, struck bus shelter, tree and utility pole
South Speed Zone
02/27/2009 16:00 Driver lost control and left roadway, vehicle flipped
The crash rate for each speed zone was calculated based on the number of reported crashes, daily
traffic volumes, segment length, and crash history duration. Table 6-3 summarizes the crash rates for
Phelps Rd NE, with a comparison to county and statewide averages.
Table 6-3: Crash Rates for Phelps Rd NE
Location Crashes
Average
Daily Traffic
(vpd)
Study
Length
(miles)
Crash
History
(months)
Crashes per
Million
Veh-Miles
Phelps Rd NE 6 1,350 1.40 66 1.61
North Speed Zone 5 1,350 1.00 66 1.84
South Speed Zone 1 1,350 0.40 66 0.97
Kitsap County1 - - - - 1.72
Washington State2 - - - - 2.57
The south speed zone and corridor as a whole have crash rates below the Kitsap County average, while
the crash rate for the north speed zone exceeds the county average. A review of the five crashes in the
north segment indicates that speed may be a factor in four of the crashes. FHWA recommends
reducing speed limits if crash rates exceed the statewide average. The average crash rate for urban
minor arterial state routes in Washington State is 2.57 crashes per million vehicle miles. No portion of
Phelps Rd NE exceeds this crash rate. Based on this and a review of the crash descriptions, the speed
limits should not be reduced because of crash history.
6.3 Speed Survey
A radar speed survey was conducted on August 12, 2013 for both segments. The weather was sunny,
dry, and clear. Table 6-4 is a summary of these studies. Traffic was light, with virtually no platoons and
a random flow rate.
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Table 6-4: Radar Speed Study Summary for Phelps Rd NE
Location Sample
Size
Speed
Limit
(mph)
Mean
Speed
(mph)
10-mph
Pace
Percent
Within
Pace
85th
Percentile
Speed (mph)
North Speed Zone
(Near Ellingsen Rd NE) 82 40 38.5 34 to 44 93% 41.0
South Speed Zone
(1000’ N of fire station) 75 30 35.7 31 to 41 79% 40.0
North Speed Zone
The speed survey for the north speed zone reveals a high (93%) number of vehicles within the 10-mph
pace speed, indicating a consistent flow speed.
The 85th percentile of 41.0 mph means that the currently posted speed limit of 40 mph is being followed
by a majority of the vehicles on the roadway segment.
Established protocol suggests setting a speed limit so that at least 85% of drivers are within compliance.
In this case, that would mean setting the speed limit at 45 mph. However, the difference between the
posted speed limit and the 85th percentile speed is minimal. Assuming no change in driver behavior,
lowering the posted speed limit would increase the percentage of drivers exceeding the posted limit
from 18% (at 40 mph) to 79% (at 35mph).
South Speed Zone
The data sample for the south speed zone was taken near the transition zone for the two speed limits
because of several factors. First, the south speed zone is primarily comprised of a large horizontal
curve. This curve will slow driver speeds and is more appropriately governed by an advisory speed sign
than a posted statutory limit. Second, the fire station and additional signing that drivers “be prepared to
stop” will tend to decrease travel speeds and negatively impact the study by preventing the true segment
travel speed from being captured. To avoid these factors, the speed survey was conducted in a tangent
segment away from the effects of the fire station signing. The only location that met these criteria was
north of the fire station near the transition zone. Tube speed measurements by Traffic Count
Consultants, Inc. were referenced to verify travel speeds within the south speed zone.
The speed survey for the south speed zone reveals a medium (78%) number of vehicles within the 10-
mph pace speed, indicating a moderately consistent flow speed.
The 85th percentile of 40.0 mph means that the currently posted speed limit of 30 mph is being deviated
from by a majority of the vehicles on the roadway segment. Established protocol suggests setting a
speed limit so that at least 85% of drivers are within compliance. In this case, that would mean setting
the speed limit at 40 mph. Several other factors need to be considered, however. First, the data near
the transition zone may have been clouded by drivers who were in the process of adjusting to a new
speed zone by either accelerating or decelerating. Second, a low crash rate indicates that this segment
does not have any issues with speed as it is currently posted, though the crash rate could change if the
speed limit is adjusted. Third, the geometry in the area, particularly the multiple horizontal curves near
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the fire station, may prohibit the speed limit from rising due to limiting factors such as sight distance.
Assuming no change in driver behavior, raising the posted speed limit would decrease the percentage of
drivers exceeding the posted limit from 85% (at 30 mph) to 13% (at 40 mph).
6.4 Issues and Candidate Mitigation
Speed – In the north speed zone, the 85th percentile speed (41.0 mph) only slightly exceeds the posted
speed limit (40 mph). Because of that, as well as similar characteristics of other 40-mph corridors on
the Island, the speed limit should not change. In the south zone, however, the situation is more
complicated. In the south zone, north of the fire station, the 85th percentile speeds for northbound
traffic (40 mph) were very similar to southbound (41 mph). Northbound traffic at this location is
accelerating out of the curve and into a higher speed zone. Southbound traffic,
however, should already be slowing due to entering the 30 mph speed zone. The
data suggests that southbound vehicles entering the south speed zone are not yet
slowing significantly to match the 10-mph speed reduction. An analysis of the
tube speed measurements by Traffic Count Consultants, Inc. reveals that just
before the fire station, 20% of drivers are travelling between 41 and 45 mph, 35%
between 36 and 40 mph, 26% between 31 and 35 mph, and only 10% between
26-30 mph. To reduce speeds for southbound traffic, a reduced speed limit
ahead (W3-5) warning sign should be installed prior to entering the 30-mph zone.
Curve Signing – The recommended signing for curves on Phelps Rd NE is inconsistent. Within the
north speed zone, W1-5 and W13-1P signs inform southbound drivers that they are approaching an S-
curve with a recommended speed of 25 mph. While traversing the S-curve, drivers encounter a 30-mph
statutory speed limit sign. These signs are not installed for northbound traffic. The large horizontal
curve south of the fire station is not marked by any signing and does not have a posted recommended
speed. Based on area maps, the curve radius for the horizontal curve appears to be tighter than the
radii for the reverse S-curves in the transition speed area, suggesting that a lower advisory speed is
appropriate. While this study did not investigate the radii or appropriate recommended travel speeds
for each curve, each curve should be evaluated either by using record drawings or a ballbank test to
establish the maximum safe travel speed and to determine the appropriate signing that should be
installed.
Wild Animals – One of six crash reports for this corridor cite wild animals as the primary cause.
Animal-based crashes can be severe as drivers may swerve quickly to avoid the animal and lose control
of the vehicle, exit the roadway, or strike a road user. Currently, there are no warning signs highlighting
the presence of animals in the area. The WSDOT Traffic Manual recommends that one of the following
criteria be met prior to installation of a deer crossing sign:
(1) Minimum of 5 documented deer/vehicle collisions per mile per year for at least two of the
past 10 years
(2) Minimum of 10 carcass counts per mile per year for at least three of the past 10 years
(3) Concurrence from region maintenance personnel
W3-5
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This analysis was only able to evaluate criterion (1) based on available information. There has been only
one crash involving deer since 2008. This criterion is not met and, therefore, wildlife warning signs are
not recommended.
Illumination – This corridor has no continuous illumination, which is consistent with rural areas
throughout Bainbridge Island. A lack of illumination can lead to drivers being unable to see their
surroundings, including traffic control devices such as signs or obstacles such as animals that must be
avoided. Because the City of Bainbridge Island does not have any warrants for illumination, this analysis
used WSDOT warrants. Illumination is warranted along roadways of this type if the segment is
classified as commercial and either the nighttime level of service is D or the nighttime crash warrant is
satisfied. This roadway segment is not classified as commercial and, therefore, does not meet
illumination warrants.
6.5 Recommendation
The following is recommended for the Phelps Rd NE corridor:
1. Maintain current speed limits and zones.
2. Install a reduced speed limit ahead (W3-5) warning sign for southbound traffic north of the 30-
mph speed zone. Monitor effectiveness of treatment.
3. Analyze whether advisory speeds are necessary for the reverse S-curves north of the fire station
and the horizontal curve between the station and NE Day Rd. Analysis may be done either by
referencing record drawings or by conducting ballbank tests.
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7.0 ENGINEERING AND SPEED SURVEY – PLEASANT BEACH DRIVE NE:
NE ODDFELLOWS RD TO FORT WARD PARK
Pleasant Beach Drive NE is a local road that connects the Lynwood Center commercial area to Fort
Ward Park. Pleasant Beach Dr NE has an average daily traffic volume of less than 500 vpd. The primary
objective for this study was to determine the appropriate speed limit for the corridor between NE
Oddfellows Rd and Fort Ward Park. Figure 7-1 shows the project limits with the posted regulatory and
warning signing along the roadway.
Figure 7-1: Pleasant Beach Dr NE corridor map with signing
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7.1 Project Area Description
Figure 7-2: Pleasant Beach Dr NE facing north Figure 7-3: Pleasant Beach Dr NE facing south
Pleasant Beach Dr NE has one marked speed zone with the characteristics listed in Table 7-1.
Table 7-1: Characteristics Summary for Pleasant Beach Dr NE
Item Pleasant Beach Dr NE
Geometry
Alignment North-south
Pavement Width 18’
Horizontal Curves Moderate near Campbell St NE
Vertical Curves Minor
Surrounding Environment
Setting Forested, Residential
Roadside Ditches Infrequent
Private Driveways Frequent
Pull-Out Areas Occasional private pull-outs near driveways (gravel), multiple Fort
Ward Park parking lots (gravel)
Clear Zones Infrequent obstacles, occasionally encroaching vegetation
Curb, Gutter and Sidewalk Not present
Lighting Not present
Traffic Control
Lane Markings Not present
Speed Limit 25 mph
Major Intersections Stop at NE Oddfellows Rd
Additional Measures Speed bump near Fort Ward Park
7.2 Crash History
One reported crash has occurred along this segment from January 1, 2008 to June 30, 2013. The crash
is summarized in Table 7-2.
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Table 7-2: Crash Report Summary for Pleasant Beach Dr NE
Date Time Description
09/03/2012 13:04 Cyclist lost control after crossing speed bump at Fort Ward Park
The crash rate for the corridor was calculated based on the number of reported crashes, daily traffic
volumes, segment length, and crash history duration. Table 7-3 summarizes the crash rate for Pleasant
Beach Dr NE, with a comparison to the county average.
Table 7-3: Crash Rate for Pleasant Beach Dr NE
Location Crashes
Average
Daily Traffic
(vpd)
Study
Length
(miles)
Crash
History
(months)
Crashes per
Million
Veh-Miles
Pleasant Beach Dr NE 1 500 0.82 66 1.22
Kitsap County1 - - - - 1.72
The corridor has a lower crash rate than the Kitsap County average. FHWA recommends reducing
speed limits if crash rates exceed the statewide average. However, statewide crash rates are not
available for local roads such as Pleasant Beach Dr NE. As such, this criterion cannot be evaluated.
7.3 Speed Survey
A radar speed survey was conducted on September 19, 2013. The weather was sunny, dry, and clear.
Table 7-4 is a summary of this study. Traffic was light, with virtually no platoons and a random flow
rate.
Table 7-4: Radar Speed Study Summary for Pleasant Beach Dr NE
Location Sample
Size
Speed
Limit
(mph)
Mean
Speed
(mph)
10-mph
Pace
Percent
Within
Pace
85th
Percentile
Speed (mph)
Pleasant Beach Dr NE 39 25 22.1 18 to 28 95% 25.0
The speed survey reveals a very high (95%) numbers of vehicles within the 10-mph pace speed,
indicating a consistent flow speed.
The 85th percentile of 25.0 mph means that the currently posted speed limit of 25 mph is being followed
by a majority of the vehicles on the roadway segment. Speed zoning theory best practices recommend
that the 85th percentile speed be captured below the posted speed limit, a condition satisfied by existing
conditions on this roadway segment. Assuming no change in driver behavior, lowering the posted
speed limit would increase the percentage of drivers exceeding the posted limit from 10% (at 25 mph)
to 69% (at 20 mph).
7.4 Issues and Candidate Mitigation
Narrow Travel Lanes – Pleasant Beach Drive NE has an 18’-wide paved surface for bi-directional travel.
Furthermore, there are no pavement markings to help guide drivers. On tangent segments, this is rarely
an issue as approaching vehicles are visible to drivers, however curved areas with limited sight distance
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may present a larger challenge for drivers. During the speed survey, multiple vehicles passed each other
near curves and slowed down in order to do so. To improve safety, W1-5 curve warning signs with a
20-mph recommended speed (W13-1P) should be installed.
Roadside environment – Exacerbating the issue of narrow travel lanes is the unforgiving roadside
condition throughout this roadway segment. Vegetation encroaches to the pavement edge,
compounding all sight-distance considerations as well as allowing no escape room beyond the narrow
pavement. With no segregated facilities for non-motorized users, local residents and those accessing
the Fort Ward Park, the combination of physical features creates a challenging environment for all users.
When considered as a whole, these factors justify a variance from the 85th percentile convention in
speed zone theory.
Illumination – This corridor has no continuous illumination, which is consistent with rural areas
throughout Bainbridge Island. A lack of illumination can lead to drivers being unable to see their
surroundings, including traffic control devices such as signs or obstacles such as animals that must be
avoided. Because the City of Bainbridge Island does not have any warrants for illumination, this analysis
used WSDOT warrants. Illumination is warranted along roadways of this type if the segment is
classified as commercial and either the nighttime level of service is D or the nighttime crash warrant is
satisfied. This roadway segment is not classified as commercial and, therefore, does not meet
illumination warrants.
W1-5 W13-1P
7.5 Recommendation
The following is recommended for the Pleasant Beach Dr NE corridor:
1. Reduce the current speed limit from 25 to 20 mph.
2. Install a W1-5 turn warning sign with a 20-mph W13-1P advisory speed sign for each direction
at the roadway curves immediately south of Campbell St NE.
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8.0 ENGINEERING AND SPEED SURVEY – SPORTSMAN CLUB ROAD NE:
NE HIGH SCHOOL ROAD TO NE NEW BROOKLYN ROAD
Sportsman Club Road NE is a minor arterial that connects SR-305 to multiple residential areas near the
center of Bainbridge Island. Sportsman Club Rd NE has an average daily traffic volume of 3,300 vpd.
The primary objective for this study was to determine the appropriate speed limit for the corridor
between NE High School Rd and NE New Brooklyn Rd. Figure 8-1 shows the project limits with the
posted regulatory and warning signing along the roadway.
Figure 8-1: Sportsman Club Rd NE corridor map with signing
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8.1 Project Area Description
Figure 8-2: Facing south Figure 8-3: Facing north
Sportsman Club Rd NE has the characteristic listed in Table 8-1.
Table 8-1: Characteristics Summary for Sportsman Club Rd NE
Item Sportsman Club Rd NE
Geometry
Alignment North-south
Lanes (per direction) 1
Lane Width 12’
Shoulder Width 4.5’
Horizontal Curves Minor
Vertical Curves Moderate
Surrounding Environment
Setting Forested
Roadside Ditches Infrequent
Private Driveways Infrequent
Pull-Out Areas Not present
Clear Zones Infrequent obstacles, occasionally encroaching vegetation
Curb, Gutter and Sidewalk Not present
Lighting Not present
Traffic Control
Lane Markings Marked centerline and edge lines
Speed Limit 40 mph (see below)
Major Intersections Stop at NE High School Rd, stop at NE New Brooklyn Rd
The speed limits for northbound and southbound traffic are not consistent. Northbound traffic enters
the study area at 40 mph and is then stepped-down to 30-mph and 20-mph during school zone hours (5
am to 7 pm, Monday through Friday). Southbound traffic is consistently in a 40 -mph speed zone. This
analysis treated the study corridor as 40-mph speed zone throughout.
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8.2 Crash Analysis
Two reported crashes have occurred along this segment from January 1, 2008 to June 30, 2013. Each
crash is summarized in Table 8-2.
Table 8-2: Crash Report Summary for Sportsman Club Rd NE
Date Time Description
08/02/2008 22:35 Driver travelled too fast for curve and left roadway
05/31/2013 08:35 Driver blacked out, ran off road, struck tree
The crash rate for the corridor was calculated based on the number of reported crashes, daily traffic
volumes, segment length, and crash history duration. Table 8-3 summarizes the crash rate for
Sportsman Club Rd NE, with a comparison to county and statewide averages.
Table 8-3: Crash Rate for Sportsman Club Rd NE
Location Crashes
Average
Daily Traffic
(vpd)
Study
Length
(miles)
Crash
History
(months)
Crashes per
Million
Veh-Miles
Sportsman Club Rd NE 2 3,300 0.56 66 0.54
Kitsap County1i - - - - 1.72
Washington State2 - - - - 2.57
The corridor has a lower crash rate than the Kitsap County average. FHWA recommends reducing
speed limits if crash rates exceed the statewide average. The average crash rate for urban minor arterial
state routes in Washington State is 2.57 crashes per million vehicle miles. Sportsman Club Rd NE does
not exceed this crash rate. Therefore, the speed limits should not be reduced because of crash history.
8.3 Speed Survey
A radar speed survey was taken on August 12, 2013. The weather was sunny, dry, and clear. Table 8-4
is a summary of this study. Traffic was light, with virtually no platoons and a random flow rate.
Table 8-4: Radar Speed Survey for Sportsman Club Road NE
Location Sample
Size
Speed
Limit
(mph)
Mean
Speed
(mph)
10-mph
Pace
Percent
Within
Pace
85th
Percentile
Speed (mph)
Sportsman Club Rd NE 188 40 37.5 32 to 42 91% 41.0
The speed survey reveals a high (91%) numbers of vehicles within the 10-mph pace speed, indicating a
consistent flow speed.
The 85th percentile of 41.0 mph means that the currently posted speed limit of 40 mph is being followed
by a majority of the vehicles on the roadway segment. Speed zoning theory best practices recommend
that the 85th percentile speed be captured below the posted speed limit in most cases, suggesting that
the speed limit should be increased to 45 mph. However, the difference between the posted speed limit
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and the 85th percentile speed is minimal. With this sample, a lower posted speed limit would increase
the percentage of drivers exceeding the posted limit from 17% (at 40 mph) to 76% (at 35 mph).
8.4 Issues and Candidate Mitigation
Speed – In the current 40-mph speed zone, the 85th percentile speed slightly exceeds the posted speed
limit. The crash rate, however, does not suggest that current speed limits need to be reduced. Because
the speed difference is minimal and the crash rate is low, the speed limits for Sportsman Club Rd NE
should not change.
Speed Zones – The current speed limits for this corridor are not
consistent: southbound is posted at 40 mph, while northbound is posted
at 40 mph, 30 mph, and 20 mph (during school zone hours only). Speed
zones should be balanced whenever possible to improve operations and
meet driver expectations. Because of a minimal crash history and no
apparent geometric restrictions, the northbound speed limit should be
raised to 40 mph in all portions of the corridor that are not currently
within a school zone. The existing 30-mph statutory speed limit sign
should be removed and replaced with a reduced school speed limit ahead
(S4-5) sign to notify drivers that they are approaching a school zone.
Illumination – This corridor has no continuous illumination, which is consistent with rural areas
throughout Bainbridge Island. A lack of illumination can lead to drivers being unable to see their
surroundings, including traffic control devices such as signs or obstacles such as animals that must be
avoided. Because the City of Bainbridge Island does not have any warrants for illumination, this analysis
used WSDOT warrants. Illumination is warranted along roadways of this type if the segment is
classified as commercial and either the nighttime level of service is D or the nighttime crash warrant is
satisfied. This roadway segment is not classified as commercial and, therefore, does not meet
illumination warrants.
8.5 Recommendation
The following is recommended for the Sportsman Club Rd NE corridor:
2. Maintain the current speed limit for the southbound direction.
3. Replace the existing 30-mph speed limit sign with a S4-5 sign to notify drivers that they are
approaching a designated school zone.
S4-5
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9.0 ENGINEERING AND SCHOOL ZONE ANALYSIS – NE NEW BROOKLYN
ROAD AT NORTH TOWN DRIVE NE
NE New Brooklyn Road is a minor arterial that connects residential areas in the middle of the Island to
other arterials near various schools and commercial areas. NE New Brooklyn Rd has an average daily
traffic volume of 3,100 vpd. The primary objective for this location is to assess if the current school
zone to the west of North Town Dr NE should be extended east to include the entrance to the North
Town Woods neighborhood. Figure 9-1 shows the project limits with the posted signing along the
roadway.
Figure 9-1: NE New Brooklyn Rd corridor map with signing
NE New Brooklyn Rd
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9.1 Project Area Description
Figure 9-2: NE New Brooklyn Rd at crosswalk Figure 9-3: NE New Brooklyn Rd school zone
NE New Brooklyn Rd, at the intersection with North Town Dr NE, has the characteristics listed in
Table 9-1.
Table 9-1: Characteristics Summary for NE New Brooklyn Rd at North Town Dr NE
Item NE New Brooklyn Rd
Geometry
Alignment East-west
Lanes (per direction) 1
Lane Width 12’
Shoulder Width 4’
Horizontal Curves None
Vertical Curves Moderate on either side of North Town Dr NE
Intersection Configuration T-intersection
Surrounding Environment
Setting Forested
Clear Zones Well-maintained
Curb, Gutter and Sidewalk Curb and sidewalk present at all NW, NE and SE corners, sidewalk
and planter strip line the south edge
Lighting Not present
Traffic Control
Lane Markings Marked centerline and edge lines
Speed Limit 30 mph
Pedestrian Facilities Marked crosswalk at east leg, curb ramps at east and north legs
Vehicle Pavement Markings Stop bars on either side of marked crosswalk
Additional Measures Small median traffic island at the beginning of North Town Dr NE
9.2 Crash History
There have been no reported crashes for this location between January 1, 2008 and June 30, 2013.
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9.3 Speed Survey
Two radar speed surveys were taken on September 19, 2013. The weather was sunny, dry, and clear.
Table 9-2 is a summary of these studies. Traffic was light, with virtually no platoons and a random flow
rate.
Table 9-2: Radar Speed Survey for NE New Brooklyn Rd
Location Sample
Size
Speed
Limit
(mph)
Mean
Speed
(mph)
10-mph
Pace
Percent
Within
Pace
85th Percentile
Speed (mph)
At Crosswalk 63 30 27.1 22 to 32 81% 32.0
Within School Zone 91 20 21.5 17 to 27 84% 26.0
9.4 Assessment
At the crosswalk, speeds generally conform to the posted speed limit of 30 mph. The percent within
pace is good, though not as high as at other locations surveyed in this report. Within the school zone,
however, the overall 85th percentile speed is significantly higher than the school zone speed of 20 mph.
Furthermore, within the school zone, there is a strong directional difference between 85th percentile
speeds. Vehicles travelling westbound moved slower that eastbound traffic (21.0 versus 28.1 mph). In
addition to entering a school zone, westbound traffic is headed toward a visible stop sign at the
intersection of NE New Brooklyn Rd and Sportsman Club Rd NE.
Eastbound traffic is not adhering to the current school zone speed requirement. The eastbound 85th
percentile speed is more than 40% higher than the posted speed limit of 20 mph. This non-compliance
is likely due to the fact that drivers entering this area from the east are unaware that the school zone is
still in effect as no school zone sign has been displayed to them. The only sign indicating that they are
within a school zone is an “end school zone” (S5-2) sign.
9.5 Recommendation
The following is recommended for the school zone near North Town Drive NE:
1. The existing school zone should be extended to include the marked crosswalk at the
intersection of NE Brooklyn Rd and North Town Dr NE. Because the marked crosswalk is
being used by children to travel to and from school, it warrants being part of a designated
school zone. As such, the current school zone should be extended east to incorporate the
crosswalk. A school zone sign should be posted in the westbound direction such that vehicles
travelling over the crest hill have ample time to react to the reduced speed limit and stop for
any children that may be present. Eastbound traffic, which is accelerating from the intersection
at Sportsman Club Rd NE, should be informed that a school zone is still in effect. A school zone
sign should be placed where the current “end school zone” sign is located for eastbound traffic.
Enacting these measures should substantially slow traffic at the crosswalk and increase safety for
crossing pedestrians. An example signing plan is shown in Figure 9-4.
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Figure 9-4: Example signing plan for NE New Brooklyn Rd
NE New Brooklyn Rd
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10.0 INTERSECTION TRAFFIC OPERATIONS – LYNWOOD CENTER ROAD
NE AND NE BAKER HILL ROAD
Lynwood Center Road NE intersects NE Baker Hill Road less than 500 feet north of the Lynwood
Center urban area. Currently, Lynwood Center Rd NE near this intersection has an average daily traffic
volume of 3,850 vpd. NE Baker Hill Rd has an average daily traffic volume of 1,700 vpd. The primary
objective for this intersection was to determine if Lynwood Center Rd NE should be stop-controlled,
creating all-way stop control at the intersection. Figure 10-1 shows the intersection with the posted
regulatory and warning signing.
Figure 10-1: Signing at Lynwood Center Rd NE & NE Baker Hill Rd
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10.1 Project Area Description
Figure 10-2: Facing north Figure 10-3: Facing west
The intersection and influence area of Lynwood Center Rd and NE Baker Hill Rd have the
characteristics listed in Table 10-1.
Table 10-1: Characteristics Summary for Lynwood Center Rd NE & NE Baker Hill Rd
Item Intersection
Geometry
Alignment Lynwood Center Rd NE: north-south
NE Baker Hill Rd: east-west
Lanes (per direction) 1
Lane Width 12’
Shoulder Width 3’
Intersection Skew 15 degrees
Approach Grades Lynwood Center Rd NE: minor
NE Baker Hill Rd NE: minor for west approach, steep for east
approach (sloping toward intersection)
Surrounding Environment
Setting Mixed, open and forested
Utility Furniture Power poles at NE and SE corners, cabinets at NE corner
Parking Angled parking on Lynwood Center Rd NE south approach, gravel
parking at NW corner
Transit Kitsap Transit bus stop at SE corner
Vegetation Overgrown at SW and NE corners
Curb, Gutter and Sidewalk Present only at SE corner
Lighting Not present
Traffic Control
Lane Markings Marked centerline and edge lines
Stop Control Lynwood Center Rd NE: no stop control
NE Baker Hill Rd: both approaches stop controlled
Legal Maneuvers Left, through, and right at all approaches
Pedestrian Facilities Marked crosswalk at south leg with curb ramp at SE corner
Vehicle Pavement Markings Stop bars: NE Baker Hill Rd; yield lines: Lynwood Center Rd NE
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10.2 Crash History
Two reported crashes have occurred within this intersection influence area from January 1, 2008 to
June 30, 2013. Each crash is summarized in Table 10-2.
Table 10-2: Crash Report Summary for Lynwood Center Rd NE & NE Baker Hill Rd
Date Time Description
01/23/2008 08:50 Driver turned northbound onto Lynwood Ctr Rd and lost control due to ice
09/22/2012 11:57 Driver stopped at stop sign but failed to yield to and struck an oncoming car
10.3 Traffic Count
A traffic count was performed from 4:00 PM to 5:00 PM on August 22, 2013. The weather was sunny,
dry and clear. The volume for all movements is summarized in Table 10-3.
Table 10-3: Intersection Turning Movements for Lynwood Center Rd NE & NE Baker Hill Rd
From NORTH From SOUTH From EAST From WEST Ped Bike
L T R L T R L T R L T R Total Total
6 154 57 7 133 1 5 11 1 45 3 3 1 11
L = left T = through R = right
10.4 Intersection Operations
Left-turning traffic from NE Baker Hill Rd frequently stopped between the stop bar and travel lanes
before turning. Sight distance for left-turn maneuvers is limited by vegetation and, occasionally, site
furniture. No crashes or significant delays were observed during the study.
Most approaching vehicles from NE Baker Hill Rd were able to clear the intersection within one minute
of stopping. The worst observed case was a roughly two-minute wait for one driver. A Synchro
analysis was performed to quantify the average delay per vehicle at the intersection. The analysis is
summarized in Table 10-4.
Table 10-4: Synchro Analysis for Lynwood Center Rd NE & NE Baker Hill Rd
Approach Traffic
Control
Average
Delay (s)
Level of
Service
Eastbound Stop 11.9 B
Westbound Stop 11.7 B
Northbound Free 0.4 -
Southbound Free 0.2 -
The Highway Capacity Manual (HCM) defines level of service (LOS) for two-way stop controlled
intersections based on average delay for a particular approach. The level of service is not calculated for
free movements. LOS B for vehicle movements is an average delay between 10 and 15 seconds.
10.5 Traffic Control Warrants
The MUTCD establishes the criteria for whether or not an intersection warrants having a traffic signal
based on volumes for the major and minor streets. A full signal warrant analysis requires an 8-hour
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minimum vehicle count. A peak hour warrant is also available, and was applied in this case because of
the limited collected data. If the peak hour warrant is not met, then it is reasonable to assume that no
warrants will be met despite not having a complete count to justify it.
Based on the above traffic count data, a peak hour warrant was evaluated for the intersection of
Lynwood Center Rd NE and NE Baker Hill Rd. Figure 10-4 shows the warrant analysis in graphical
form.
Figure 10-4: MUTCD traffic signal peak hour warrant
The major street (Lynwood Center Rd NE) volume for this intersection during the peak hour is 358,
while the minor street higher volume approach (NE Baker Hill Rd, eastbound) is 51. The minimum
required peak hour volume for the minor street higher volume approach is 100 vehicles. The volumes
do not meet this warrant and are not expected to meet either the four- or eight-hour warrants.
While all-way stop-controlled intersections do not have a warrant process in the MUTCD, several
justifications are provided for their installation. These justifications include: relatively equal major and
minor street volumes, temporary traffic control measure prior to signal installation, correctable 12-
month crash history, and 300 vehicles per hour (vph) for the major street over eight hours in a single
day with 200 vph for the minor street over the same eight hours. Based on the major to minor street
volume ratio (5.26), crash history, and vehicle count, these justifications are not met.
10.6 Issues and Candidate Mitigation
Intersection Traffic Control – All-way stop control is not warranted at this intersection. The approach
delays for the east and west approaches are under 12 seconds, meaning that the existing traffic control
does not cause undue delay to any driver, even at the peak hour. While installing stop signs for the
Lynwood Center Rd NE approaches might decrease delay for east and westbound traffic, it would
substantially increase delay for north and southbound traffic. Additionally, the peak hour MUTCD
warrant for signals (or all-way stops) is not met in this case because the minor street volumes are too
low. Two-way stop control is appropriate for this intersection.
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Sight Distance – Traffic on NE Baker Hill Rd has limited sight distance at the marked stop bars. Most
drivers continue beyond these before stopping at the edge of the closest travel lane on Lynwood Center
Rd NE. The reduced sight distance is a combination of overgrown vegetation, the intersection skew,
and various site furniture including a wooden bus stop. To improve sight distance, the stop bars should
be moved closer to the north-south travel lanes and overgrown vegetation should be trimmed.
Signing and Markings – Both northbound and southbound Lynwood Center Rd NE approaches have a
Yield Here for Pedestrians regulatory sign (MUTCD Sign R1-5) and an associated yield line. Based on
comments and discussions with the City of Bainbridge Island, these markings have resulted in driver
confusion. Because of this confusion, additional signing to Baker Hill Road has been added, including a 2-
way supplemental sign and a Cross Traffic Does Not Stop warning sign. The 2009 MUTCD states that
the 2-way supplemental plaque is prohibited. Removal of the sign will help reduce driver confusion
between all-way stop locations. Additionally, drivers on NE Baker Hill Rd may misinterpret the yield
line as a stop line and assume that northbound and southbound traffic will stop. Removal of the yield
line will reduce driver confusion.
Crosswalk – Fluorescent yellow-green crosswalk signs (W11-2) and supplemental warning plates (W16-
7P) should be installed at the crosswalk to warn drivers of pedestrians. Additionally, adequate
illumination should be provided at both corners to improve pedestrian safety and further increase
visibility.
R1-5 W11-2 W16-7P
10.7 Recommendation
The following is recommended for the intersection of Lynwood Center Rd NE and NE Baker Hill Rd:
1. Maintain existing east and westbound stop control for NE Baker Hill Rd.
2. Remove and replace existing stop lines for east and westbound traffic on NE Baker Hill Rd.
Place stop bar approximately 4-feet from the shoulder edge on Lynwood Center Rd NE.
3. Remove existing “2-way” supplemental plaque on NE Baker Hill Rd approaches.
4. Remove existing yield line markings.
5. Install fluorescent yellow-green pedestrian crosswalk warning signs (W11-2) and
supplemental warning plaques (W16-7P) at the crosswalk. Maintain existing “yield here to
pedestrians” (R1-5) signs.
6. Review illumination to determine if adequate visibility is available at the crosswalk.
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11.0 INTERSECTION TRAFFIC OPERATIONS – MILLER ROAD NE AND NE
KOURA ROAD
Miller Road NE intersects NE Koura Road 1.4 miles west of SR-305. Currently, Miller Rd NE near this
intersection has an average daily traffic volume of 4,800 vpd. NE Koura Rd has an average daily traffic
volume of 1,625 vpd. The primary objective for this intersection was to determine if Miller Rd NE
should be stop-controlled, creating all-way stop control at the intersection. Figure 11-1 shows the
intersection with the posted regulatory and warning signing.
Figure 11-1: Signing at Miller Rd NE & NE Koura Rd
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11.1 Project Area Description
Figure 11-2: NW corner facing north Figure 11-3: SW corner facing south
The intersection and influence area of Miller Rd NE and NE Koura Rd have the characteristics listed in
Table 11-1.
Table 11-1: Characteristics Summary for the Intersection of Miller Rd NE & NE Koura Rd
Item Intersection
Geometry
Alignment Miller Rd NE: north-south
NE Koura Rd: east-west
Lanes (per direction) 1
Lane Width 11’
Intersection Skew 15 degrees
Approach Grades Lynwood Center Rd NE: minor
NE Baker Hill Rd NE: minor for east approach, steep for west
approach (sloping away from intersection)
Surrounding Environment
Setting Forested
Utility Furniture Multiple utility poles and junction boxes
Parking Not present, wide unpaved pull-out area on east leg
Transit Not present
Vegetation Some trees in clear zone
Shoulders Present on all sides of all approaches
Curb, Gutter and Sidewalk Not present
Lighting Not present
Traffic Control
Lane Markings Miller Rd NE: Marked centerline and edge lines
NE Koura Rd: Single dashed yellow centerline
Stop Control Miller Rd NE: no stop control
NE Koura Rd: both approaches stop controlled
Legal Maneuvers Left, through, and right at all approaches
Pedestrian Facilities Not present
Vehicle Pavement Markings Stop bars on NE Koura Rd
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11.2 Crash History
Eight reported crashes have occurred within this intersection influence area from January 1, 2008 to
June 30, 2013. Each crash is summarized in Table 11-2.
Table 11-2: Crash Report Summary for Miller Rd NE & NE Koura Rd
Date Time Description
08/01/2008 15:06 Vehicle stopped at stop sign on Koura was rear-ended
08/01/2008 15:17 Driver attempted to make U-turn at intersection and was T-boned
12/31/2008 17:50 Driver sideswiped other vehicle while turning at intersection
10/13/2009 18:55 Westbound driver was struck by a southbound driver
10/24/2009 00:10 Eastbound driver failed to stop at stop sign, hit southbound vehicle
11/05/2009 10:00 Driver who was waiting for a turn was rear-ended
06/26/2011 11:21 Driver failed to yield right-of-way and hit another vehicle
01/22/2013 15:27 Driver turning east onto Koura failed to yield to northbound vehicle
11.3 Traffic Count
A traffic count was performed from 3:15 – 4:15 PM on August 12, 2013. Conditions were sunny, dry
and clear. The volume for all movements is summarized in Table 11-3.
Table 11-3: Intersection Turning Movement s for Miller Rd NE & NE Koura Rd
From NORTH From SOUTH From EAST From WEST
L T R L T R L T R L T R
18 134 6 10 160 32 42 10 20 4 12 10
L = left T = through R = right
11.4 Intersection Operations
Drivers are presented with rural roadway characteristics typical to the general condition of many
roadways in the area as they approach this intersection from all directions. The intersection is not
easily identified in approaching it along Miller Rd NE due to trees and other roadside foliage, particularly
in the southbound approach due to the crest vertical curve and horizontal curve. Of particular concern
is the sight distance from the stop-bar decision point on the western leg. Eastbound traffic entering the
intersection is challenged by a combination of factors:
A utility pole and telephone splice box at the northwest corner
Vegetation on the northwest corner
The +8% eastbound approach grade
The horizontal and crest vertical curves partially obstructing southbound traffic sight line
No shoulder / narrow lanes
Intersection skew
Shadowing created by the overhead tree canopy
Lack of area lighting
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Vehicles passing through the intersection on Miller Rd NE travel roughly 35 mph. The south and east
approaches are relatively tangent and level. The north leg approach has both a horizontal curve and a
crest vertical curve reducing sight distance.
A Synchro analysis was performed to quantify the average delay per vehicle at the intersection. The
analysis is summarized in Table 11-4.
Table 11-4: Synchro Analysis for Miller Rd NE & NE Koura Rd
Approach Traffic
Control
Average
Delay (s)
Level of
Service
Eastbound Stop 12.2 B
Westbound Stop 12.0 B
Northbound Free 0.4 -
Southbound Free 0.9 -
The HCM defines LOS for two-way stop controlled intersections based on average delay for a particular
approach. The level of service is not calculated for free movements. LOS B for vehicle movements is an
average delay between 10 and 15 seconds.
11.5 Traffic Control Warrants
The MUTCD establishes the criteria for whether or not an intersection warrants having a traffic signal
based on volumes for the major and minor streets. A full signal warrant analysis requires an 8-hour
minimum vehicle count. A peak hour warrant is also available, and was applied in this case because of
the limited collected data. If the peak hour warrant is not met, then it is reasonable to assume that no
warrants will be met despite not having a complete count to justify it.
Based on the above traffic count data, a peak hour warrant was evaluated for the intersection of Miller
Rd NE and NE Koura Rd. Figure 11-4 shows the warrant analysis in graphical form.
The major street (Miller Rd NE) volume for this intersection during the peak hour is 360, while the
minor street higher volume approach (NE Koura Rd, WB) is 72. The minimum required peak hour
volume for the minor street higher volume approach is 100 vehicles. The volumes do not meet this
warrant and are not expected to meet either the eight- or four-hour warrant.
Figure 11-4: MUTCD traffic signal peak hour warrant
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While all-way stop-controlled intersections do not have a warrant process in the MUTCD, several
justifications are provided for their installation. These justifications include: relatively equal major and
minor street volumes, temporary traffic control measure prior to signal installation, correctable 12-
month crash history, and 300 vph for the major street over eight hours in a single day with 200 vph for
the minor street over the same eight hours. Based on the major to minor street volume ration (3.67),
crash history, and vehicle count, these justifications are not met.
11.6 Issues and Candidate Mitigation
Intersection Traffic Control – All-way stop control is not warranted at this intersection. The approach
delays for the east and west approaches are under 13 seconds, meaning that the existing traffic control
does not cause undue delay to any driver, even at the peak hour. While installing stop signs for the
Miller Rd NE approaches might decrease delay for east and westbound traffic, it would substantially
increase delay for north and southbound traffic. Additionally, the peak hour MUTCD warrant for signals
(or all-way stops) is not met in this case because the minor street volumes are too low. The
intersection should retain its current stop sign arrangement.
Sight Distance – Sight distance is limited due to vegetation and site furniture such as utility poles and
junction boxes. The western leg is particularly troublesome as the approach grade is roughly 8%.
According to A Policy on Geometric Design of Highways and Streets, additional sight distance is required for
traffic that approaches an intersection at a grade exceeding 3%. To reduce this risk of increased
crashes, obstacles should be removed from the critical sight locations near the intersection. Where
obstacles cannot be removed, maintenance efforts should be taken to improve sight distance as much as
possible.
11.7 Recommendation
The following is recommended for the intersection of Miller Rd NE and NE Koura Rd:
1. Maintain existing east and westbound stop control for NE Koura Rd.
2. Provide proper sight distance by trimming or removing overgrown vegetation as necessary.
3. Install a stop sign ahead (W3-1) warning sign for the west NE Koura Rd approach.
W3-1
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12.0 INTERSECTION TRAFFIC OPERATIONS – NE VALLEY ROAD AND
SUNRISE DRIVE NE
NE Valley Rd intersects Sunrise Dr NE at the Rolling Bay commercial area. Currently, NE Valley Rd
near this intersection has an average daily traffic volume of 2,800 vpd. Sunrise Dr NE has an average
daily traffic volume of 1,500 vpd. The primary objective for this intersection was to determine if NE
Valley Rd should be stop-controlled, creating all-way stop control. Figure 12-1 shows the intersection
with the posted regulatory and warning signing.
Figure 12-1: Signing at NE Valley Rd & Sunrise Dr NE
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12.1 Project Area Description
Figure 12-2: West approach Figure 12-3: Intersection freight delivery
The intersection and influence area of NE Valley Road and Sunrise Drive NE have the characteristics
listed in Table 12-1.
Table 12-1: Characteristics Summary for the Intersection of NE Valley Rd & Sunrise Dr NE
Item Intersection
Geometry
Alignment NE Valley Rd: east-west
Sunrise Dr NE: north-south
Lanes (per direction) 1
Lane Width 11’
Intersection Skew None
Approach Grades None
Surrounding Environment
Setting Commercial
Utility Furniture Not present
Parking Various configurations throughout influence area
Transit Not present
Vegetation Not present
Shoulders Present on all sides of all approaches
Curb, Gutter and Sidewalk Curb present only at NW corner
Lighting Not present
Traffic Control
Lane Markings Marked centerline and edge lines
Stop Control NE Valley Rd: no stop control
Sunrise Dr NE: both approaches stop controlled
Legal Maneuvers Left, through, and right at all approaches
Pedestrian Facilities Not present
Vehicle Pavement Markings Not present
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12.2 Crash History
One reported crash has occurred within this intersection influence area from January 1, 2008 to June
30, 2013. The crash is summarized in Table 12-2.
Table 12-2: Crash Report Summary for NE Valley Rd & Sunrise Dr NE
Date Time Description
04/14/2008 13:31 Driver failed to yield and t-boned another vehicle
12.3 Traffic Count
A traffic count was performed from 4:15 – 5:25 PM on August 12, 2013. The weather was sunny, dry
and clear. The volume for all movements is summarized in Table 12-3.
Table 12-3: Intersection Turning Movements for NE Valley Rd & Sunrise Dr NE
From NORTH From SOUTH From EAST From WEST Ped Bike
L T R L T R L T R U L T R Total Total
3 9 59 12 8 4 3 36 21 2 83 27 20 35 21
L = left T = through R = right U = U-turn
12.4 Speed Survey
A radar speed study was conducted for NE Valley Rd on November 4, 2013. Data was captured for
eastbound traffic before entering the 25-mph speed zone as well as before entering the intersection
influence area. The weather was overcast and dry. Table 12-4 is a summary of these studies. Traffic
was light, and vehicles that were slowed or obstructed by parking activities were not considered.
Table 12-4: Radar Speed Study Summary for NE Valley Rd
Location Sample
Size
Speed
Limit
(mph)
Mean
Speed
(mph)
10-mph
Pace
Percent
Within
Pace
85th
Percentile
Speed (mph)
35-mph Speed Zone 29 35 34.1 28 to 38 83% 39.5
25-mph Speed Zone
(outside influence area) 38 25 23.2 18 to 28 97% 27
12.5 Intersection Operations
There is considerable local access demand for the commercial establishments, which include a post
office adjacent to the intersection. The local activities generate a noticeable presence of pedestrian and
bicycle traffic in and around the intersection area. Combined with the local destinations at the
intersection there is a significant sub-regional travel demand through the intersection. The most
significant traffic demands for the intersection are the eastbound-left and southbound-right movements.
Additionally, east-west through traffic is also substantial.
There is a mixture of on-street and adjacent off-street parking in the area, and a fairly consistent lack of
access management. Fairly high parking demand persists throughout the business day, with a high
turnover rate due principally to the post office generation. In the immediate intersection area there is a
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mixture of on-street parallel parking and 90-degree parking accessible directly from the street.
Combined with the high intersection turning volumes, lack of segregated facilities for pedestrian and
bicycle movement, and a low level of access control and traffic control devices (including advance
warning signing, marked crosswalks or stop bars), the intersection area presents a localized and isolated
area of high friction and unpredictability incongruous with the surrounding rural roadway system.
A Synchro analysis was performed to quantify the average delay per vehicle at the intersection. The
analysis is summarized in Table 12-5.
Table 12-5: Synchro Analysis for NE Valley Rd & Sunrise Dr NE
Approach Traffic
Control
Average
Delay (s)
Level of
Service
Eastbound Free 4.8 -
Westbound Free 0.4 -
Northbound Stop 11.1 B
Southbound Stop 9.3 A
The HCM defines LOS for two-way stop controlled intersections based on average delay for a particular
approach. The level of service is not calculated for free movements. LOS A for vehicle movements is
an average delay of 10 seconds or less. LOS B for vehicle movements is an average delay between 10
and 15 seconds.
12.6 Traffic Control Warrants
The MUTCD establishes the criteria for whether or not an intersection warrants having a traffic signal
based on volumes for the major and minor streets. A full signal warrant analysis requires an 8-hour
minimum vehicle count. A peak hour warrant is also available, and was applied in this case because of
the limited collected data. If the peak hour warrant is not met, then it is reasonable to assume that no
warrants will be met despite not having a complete count to justify it.
Based on the above traffic count data, a peak hour warrant was evaluated for the intersection of NE
Valley Rd and Sunrise Dr NE. Figure 12-4 shows the warrant analysis in graphical form.
Figure 12-4: MUTCD traffic signal peak hour warrant
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The major street (NE Valley Rd) volume for this intersection during the peak hour is 192, while the
minor street higher volume approach (Sunrise Dr NE, SB) is 71. The minimum required peak hour
volume for the minor street higher volume approach is 100 vehicles. The volumes do not meet this
warrant and are not expected to meet either the eight- or four-hour warrant.
While all-way stop-controlled intersections do not have a warrant process in the MUTCD, several
justifications are provided for their installation. These justifications include: relatively equal major and
minor street volumes, temporary traffic control measure prior to signal installation, correctable 12-
month crash history, and 300 vph for the major street over eight hours in a single day with 200 vph for
the minor street over the same eight hours. Based on the major to minor street volume ration (2.02),
crash history, and vehicle count, these justifications are not met.
12.7 Issues and Candidate Mitigation
Stop Control – All-way stop control is not warranted at this intersection. The approach delays for the
north and south approaches are under 12 seconds, meaning that the existing traffic control does not
cause undue delay to any driver, even at the peak hour. While installing stop signs for the Miller Rd NE
approaches might decrease delay for east and westbound traffic, it would substantially increase delay for
north and southbound traffic. Additionally, the peak hour MUTCD warrant for signals (or all-way stops)
is not met in this case because the minor street volumes are too low. The intersection should retain its
current stop sign arrangement.
Speed on NE Valley Rd – Travel speeds prior to entering the 25-mph speed zone are higher than ideal.
The 85th percentile speed in the 35-mph zone is 39.5 mph. This study only measured eastbound traffic,
which at this location is on a very steep downgrade, which is likely contributing to higher operating
speeds. Within the 25-mph speed zone, however, travel speeds are substantially lower. The 10-mph
pace drops by 10 mph between the two zones, and the 85th percentile speed is reduced from 39.5 mph
to 27 mph. The difference between the posted speed limit and 85th percentile speed in the intersection
area does not present an issue as the difference is minor. To calm speeds in the 35-mph zone, a
reduced speed ahead (W3-5) sign should be installed prior to eastbound traffic entering the 25-mph
zone. It is also noted that the commercial area and its influence zone have grown westward and
northward in recent years and now extend beyond the existing location of the speed limit change on NE
Valley Rd and Sunrise Dr NE, respectively. To incorporate the influence zone within the 25-mph zone,
and noting that speeds at the western end of this area are higher than desired, it is recommended that
the 25-mph zone be extended somewhat further to the west and north.
Channelization – Stop bars should be installed at each stop-controlled approach. Due to the pedestrian
nature of the area, marked crosswalks should be installed across all legs to improve safety.
Signing – Warning signs (W11-2) should be installed at the crosswalk to inform drivers of possible
pedestrian activity.
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W3-5 W11-2 W16-7P
12.8 Recommendation
1. Maintain existing north and southbound stop control for Sunrise Dr NE.
2. Install stop bars for both Sunrise Dr NE approaches.
3. Install marked crosswalks at all legs.
4. Install a crosswalk (W11-2) sign and a supplemental warning plaque (W16-7P) at each crosswalk.
5. Relocate the existing speed limit signs (eastbound 25 mph and westbound 35 mph)
approximately 200’ westward on NE Valley Rd.
6. Relocate the existing speed limit sign (northbound 35 mph) approximately 200’ northward on
Sunset Dr NE.
7. Install a reduced speed limit ahead (W3-5) sign for eastbound traffic prior to entering the 25-
mph intersection speed zone.
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13.0 REFERENCES
American Association of State Highway and Transportation Officials. A Policy on Geometric Design of
Highways and Streets, 2011.
American Association of State Highway and Transportation Officials. Guide for the Development of Bicycle
Facilities, 2012.
Federal Highway Administration. Manual on Uniform Traffic Control Devices, 2009 edition with 2012
revisions.
Washington State Department of Transportation. WSDOT 2011 Collision Report.
Washington State Department of Transportation. WSDOT 2011 Traffic Manual.
1 Kitsap County crash rate covers all types of roadways and crashes.
2 Washington State crash rate covers only state routes. 2.57 is the crash rate for urban minor arterials. No crash
rate is published for local state routes.
3 See MUTCD Section 2C.22
4 See MUTCD Section 2C.64
5 See MUTCD Section 2C.38