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Map 2 Crashes in Ann Arbor by Severity

Map 3 Crashes in Ypsilanti by Severity

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Source: Roadsoft GIS


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Map 5 & 6: Bicycle and Pedestrian Crashes in Ann Arbor and Ypsilanti

Map 5 Bicycle and Pedestrian Crashes in Ann Arbor

Map 6 Bicycle and Pedestrian Crashes in Ypsilanti



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Chart 3 graphically depicts crash types as a percent of total crashes. Rear End crashes, the most common crash type, made up 32.5% of the Washtenaw County crashes and Single Motor Vehicle crashes were the next most common at 26.4% of all crashes. Table 1 shows crash type by percent of crashes; table 2 lists crash types by municipality.

Crash Type Percent Total

Single motor vehicle 26.40% 2970

Head-on 1.19% 134

Head-on / left turn 1.29% 145

Angle 16.33% 1836

Rear-end 32.50% 3654

Rear-end left turn 0.60% 67

Rear-end right turn 0.70% 79

Sideswipe same direction 13.05% 1467

Sideswipe opposite direction 2.12% 238

Other / unknown 5.80% 652

Uncoded & errors 0.00% 0

Total Crashes 100.00% 11242

Table 1: Crash type by percent of crashes

Angle Head-on

Head-on / Left Turn

Other / Unknown

Rear-end

Rear-end Left Turn

Rear-end Right Turn

Sideswipe Opposite Direction

Sideswi-pe Same Direction

Single Motor Vehicle

Grand Total

Cities and Villages

Ann Arbor 752 37 53 305 1479 16 29 74 676 406 3827

Barton Hills 0 0 0 0 0 0 0 0 0 4 4

Chelsea 28 2 2 24 41 4 3 3 12 29 148

Dexter 25 2 1 7 29 1 0 5 3 14 87

Manchester 10 2 0 3 5 1 0 4 3 15 43

Milan 12 0 1 18 10 1 0 1 5 4 52

Saline 38 4 6 11 79 3 2 4 21 25 193

Ypsilanti 187 13 10 68 278 4 6 13 170 100 849

Total 1052 60 73 436 1921 30 40 104 890 597 5203

Townships

Ann Arbor Twp. 27 6 6 21 255 2 5 4 90 261 677

Augusta Twp. 11 3 1 2 14 2 1 4 2 47 87

Bridgewater Twp.

0 0 0 1 2 0 0 2 0 49 54

Dexter Twp. 7 3 2 1 11 2 0 3 2 78 109

Freedom Twp. 2 0 0 0 1 0 0 1 1 21 26

Lima Twp. 5 1 2 4 41 1 0 14 101 169

Lodi Twp. 11 1 2 16 1 0 4 3 53 91

Lyndon Twp. 4 1 1 2 4 0 0 1 3 39 55

Manchester Twp.

3 0 0 1 5 0 0 0 1 55 65

Northfield Twp. 17 2 3 13 95 3 0 5 31 156 325

Pittsfield Twp. 265 17 14 51 546 5 8 22 140 300 1368

Salem Twp. 13 1 0 2 28 1 1 7 12 85 150

Saline Twp. 3 1 1 1 4 1 0 1 2 33 47

Scio Twp. 78 7 6 20 126 7 6 14 57 259 580

Sharon Twp. 5 1 1 3 7 1 0 2 3 42 65

Superior Twp. 43 3 5 7 89 4 2 12 23 146 334

Sylvan Twp. 12 1 1 6 28 0 0 5 15 144 212

Webster Twp. 9 3 2 4 18 0 0 11 5 89 141

York Twp. 22 1 1 7 43 1 3 4 12 128 222

Ypsilanti Twp. 247 22 26 68 400 7 12 32 161 287 1262

Total 784 74 72 216 1733 37 39 134 577 2373 6039

Washtenaw county

1836 134 145 652 3654 67 79 238 1467 2970 11242

Table 2: Crash Types by Municipality

Char t 3 : Washtenaw Count y Crashes by Type

Source: MichiganTrafficCrashFacts.org

58.9% of crashes in 2014 were either single motor vehicle or rear-end crashes

Source: MichiganTrafficCrashFacts.org

Total crashes

Single motor vehicle or rear-end crashes

14 15

Driver Condition Count Percent

Sober 10922 97.2%

Intoxicated (BAC > 0.08) 320 2.8%

Total Crashes 11242 100.0%

Table 5: Crashes Involving Alcohol

Alcohol Related Crashes

Police officers indicate if alcohol was a factor for each driver involved in a crash. In 2003, the State of Michigan revised its drunken driving laws from Driving under the Influence of Liquor (DUIL) to the violation of Operating While Intoxicated (OWI). With the name change there was a Blood Alcohol Concentration (BAC) reduction from 0.10 to 0.08. The law includes a “zero-tolerance” policy for those under the age of 21. This means that a BAC level at or above 0.02 is illegal for those under 21 years of age. Commercial operators are in violation of the OWI law with a BAC of 0.04. Table 5 shows the number of crashes involving alcohol. The alcohol use data shows that 2.8% of drivers involved in Washtenaw County crashes were above the OWI standard of .08 BAC or .04 BAC if operating a commercial vehicle.

Source: www.MichiganTrafficCrashFacts.org

Injury Severity Sober Alcohol Use Total Percent Alcohol Use

Alcohol Use

Percent Alcohol Use

Fatal 21 8 29 27.6% 8 27.6%

Incapacitating injury 101 25 126 19.8% 25 19.8%

Non-incapacitating injury 424 48 472 10.2% 48 10.2%

Possible injury 1184 64 1248 5.1% 64 5.1%

No injury 9192 175 9367 1.9% 175 1.9%

Total Injury Crashes 1730 145 1875 7.7% 145 7.7%

Table 6: Crashes Involving Alcohol by Injury Severity


2.8% of all crashes involved alcohol but 7.7% of injury crashes involved alcohol

The data in Table 6 reveals the injury impact of alcohol use while driving. In crashes with a fatality, 27.6% involved alcohol. For crashes where injuries occurred, 7.7% involved alcohol. Injury severity increases significantly when alcohol is a factor.

Pedestrian and Bicycle Related Crashes

As the use of non-motorized transportation increases throughout the county, it is important to document bicycle and pedestrian crashes. Below Tables 7 and 8 provide bicycle and pedestrian crashes by injury. Table 9 identifies whether a non-motorized facility was available where the crash occurred. Table 10 identifies vehicular crashes involving a bicycle or pedestrian by municipality. Both bicycle and pedestrian crashes occurred more frequently in more urban communities.

Bicyclist involved % of Bicycle Crashes

Fatal 1 1.0%

Incapacitating injury 10 10.2%

Nonincapacitating injury 43 43.9%

Possible injury 26 26.5%

No injury 18 18.4%

Total Bicyclist Injury Crashes 80 81.6%

Table 7: Bicycle Crash Injuries


% of Bicycle Crashes % of Pedestrian Crashes

5.9%1%Chart 5: Share of bicyclist/pedestrian injury crashes in the total bicycle/pedestrian crashes

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