2008 TOWN OF CASTLE ROCK MOTOR VEHICLE ACCIDENT FACTS

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1 2008 TOWN OF CASTLE ROCK MOTOR VEHICLE ACCIDENT FACTS

2 2008 TOWN OF CASTLE ROCK MOTOR VEHICLE ACCIDENT FACTS ACKNOWLEDGEMENTS This report was assembled from data provided by the Castle Rock Police Department Accident report data from the year Each accident record, whether completed by a local police officer or a member of the Colorado State Patrol, was sent to Castle Rock and entered into a centralized database maintained by the Public Works Department The report itself was created by personnel in the Public Works Department. For more information on the capability or additional crash information contact: Libby E. Mueller Transportation Engineering Division Town of Castle Rock 4175 N. Castleton Ct Castle Rock, CO

3 Table of Contents Public Works Director s Letter i Executive Summary. 1 Quick Facts.. 2 Accident Rates by Location. 3-6 Time Trends. 7 Types of Crashes 8 Involvement by Age and Gender. 9 Accident Location. 10 Accident Environment 11 The Driver 12 Alcohol and Drug Involvement. 13 Annual Trends Road & Intersection Safety Definitions 20

5 EXECUTIVE SUMMARY 2008 CASTLE ROCK MOTOR VEHICLE ACCIDENT FACTS The mission of the Public Works Department is to provide Public Service and Safety through Quality Public Infrastructure. One aspect of furthering this mission is to analyze accident data on a regular basis in order to identify where the roadway environment may be a contributing factor to accidents, developing options for improvements, and programming projects for correction. Since 2004, when Public Works first reported accident statistics, the numbers of fatalities, and persons injured have been declining. Additionally, the crash rate per town population has also been decreasing since These trends are encouraging indications of the overall safety of travel on Town roadways. are the result of many factors. These factors can generally be classified into three main categories: 1) human factors, 2) vehicle factors, and 3) roadway environment. By far, the largest percentage of accidents can be attributed to human factors. Sadly, these are the factors all of us who drive can control and are usually the simplest to correct. Basic driver awareness and respect for all users of the Town s roadways will go the farthest towards reducing the number of accidents. The tools to attack human factors and change driver behavior however aren t always effective. Getting the facts out to drivers, police enforcement, and the use of public awareness campaigns can assist with increasing awareness. However it will take conscious decisions by all drivers to change behavior when behind the wheel. Addressing vehicle factors is also the responsibility of everyone who owns and operates a motor vehicle. Ensuring that vehicles are in good shape to operate efficiently on the roads will also greatly assist with reducing the number of accidents. Regular vehicle inspections along with preventative maintenance procedures will help reduce the chances of an accident occurring as a result of a vehicle malfunction. The roadway environment is something that is out of the driver s control. The goal in this regard is to identify locations where roadways could be a contributing factor and implement treatments to correct these. Public Works uses statistical modeling to identify the locations where corrections to the roadway environment may improve safety. This helps direct limited resources to the locations where the most benefit can be obtained and avoids directing these resources toward locations where problems may not exist. The following locations have been identified from several years of historical records as locations where roadway improvements may benefit transportation safety: Intersection Ownership Agency 1. SH 86 & Crowfoot Valley Dr CDOT 2. SH 86 & Fifth St CDOT The Colorado Department of Transportation (CDOT) will be provided with these findings and support provided where possible to assist them with further review of these locations for improvements. Road safety begins with all of us. Please remember to be courteous and cautious every time you get behind the wheel. 1

6 2008 QUICK FACTS The 2008 Toll The 2007 Toll The 2006 Toll Persons Killed Persons Injured Reported One traffic accident was reported every 16.4 Hours on average. One out of every eight accidents involved an injury. Of all drivers involved in accidents, 16% were age 19 or under, and 24 % were under 25 Years of age. 9.5% were over the age of 60. Of all accidents 21 % occurred at night. The 2008 pedestrian death toll was 0. There were 0 fatalities among motorcycle or moped riders. 2

7 ACCIDENT RATES BY LOCATION Intersections # Avg. Volume through intersection Rate Rank based on Rate Factory Shops Blvd and New Memphis Ct Wilcox Street and Wolfensberger Rd St Hwy 86 and Crowfoot Valley Rd Fifth St and Front St Fifth St and Ridge Rd Meadows Pkwy and Prairie Hawk Dr St Hwy 85 and Meadows Pkwy St Hwy 86 and Allen Wy Meadows Pkwy and Factory Shops Blvd St Hwy 86 and Front St I-25 and Meadows Pkwy Plum Creek Pkwy and Perry St Wilcox St and Fifth St St Hwy 86 and Trail Boss Dr I-25 and St Hwy Street Segments St Hwy E/O Ridge Rd St Hwy N/O Crimson Sky Dr Ridge Rd 500 S/O Fifth St St Hwy N/O Fifth St Number of Map location Average Daily Traffic Rate Rank Based on Rate

8 Street Segments St Hwy N/O Rising Sun Dr St Hwy W/O Enderud St Hwy E/O Front St St Hwy W/O Avenida Del Sol Number of Map location Average Daily Traffic Rate Rank Based on Rate ****Segment study was based on segments with more than 1 accident in any location. 4

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11 TIME TRENDS MONTH OF YEAR % Deaths % January February March April May June July August September October November December Total DAY OF WEEK % Deaths % Sunday Monday Tuesday Wednesday Thursday Friday Saturday Total TIME OF DAY % Deaths % Midnight :00am :00am :00am :00am :00am :00am :00am :00am :00am :00am :00am :00pm :00pm :00pm :00pm :00pm :00pm :00pm :00pm :00pm :00pm :00pm :00pm Total

12 Number of Fatalies TYPES OF CRASHES FIRST HARMFUL EVENT Number of Injuries Number of % of Hit Other Vehicle Hit Fixed or Other Object Rollover Hit Animal Hit Pedestrian Hit Bicyclist Hit Railway Train Hit Parked Vehicle All Others TOTAL VEHICLE TYPE Vehicles Involved in % of Vehicles Auto SUV Pick-up Truck(over 10,000 lbs) 46 4 Motorcycle/Moped 12 2 Bicycle 5.5 Other 8.5 TOTAL

13 INVOLVEMENT BY AGE AND GENDER Note: 9% of accidents reported were unknown age/gender. Percent of Drivers Involved in Traffic by Age and Gender 10 Percent Involvement < >70 Male Female Age 9

14 ACCIDENT LOCATION Intersections: Intersections By Classification Number Of Number Of People Killed Number Of People Injured Arterial/Arterial Arterial/Collector Collector/Collector Collector/Local Local/Local Total Non-Intersections: Segments Number of Number of People Killed Number of People Injured Multi-lane Arterial or Collector Two-lane Arterial Or Collector Local Total

15 ACCIDENT ENVIRONMENT Traffic control % Railroad Device 0 0 Yield Sign 2 1 Stop Sign Traffic Signal None Total Weather % Clear Rain 15 3 Snow/Sleet Other 6 1 Total Road Conditions % Dry Wet 39 7 Icy/Slushy Other 13 3 Total Lighting Condition % Day Night Total

16 THE DRIVER Primary Cause of % Failed to Yield Right of Way Careless/Reckless Driving Violation of Red Signal 13 2 Unsafe Backing 14 2 Speeding too fast for conditions 25 5 Following too closely 18 4 Turned Left in Front of Approaching Traffic 14 2 All Other/Unknown Total Condition of Drivers Drivers % No Defect or Unknown DUI or Other Cell Phone 12 1 (Alcohol related accidents are found in a separate table on the next page.) 12

17 ALCOHOL AND DRUG INVOLVEMENT Number of Involving Drivers Influenced by Alcohol or Drugs Age All Drivers Male Female < > Total

18 ANNUAL TRENDS The following tables present data about police-reported motor vehicle crashes over time (in yearly increments). This is the fifth year that annual reporting of accident data has occurred. As such, trends are just beginning to establish themselves. Below are some facts that can be interpolated from these charts. - The total number of crashes increased by an average of 1% over the five years. The biggest increase was from 2004 to 2005 (15%) with a 6% increase from 2006 to 2007, and a 16% decrease from 2007 to Compared against the increase in the Town s population the total crash rate per 1,000 people decreased by 22.8% (from 15.2 crashes per 1,000 population to 11.7 crashes per 1,000 population) over the same five-year period. What s not known is the total crash rate per vehicle miles traveled. This helps to better understand the accident risk associated with exposure. Nationally, the total distance the average person travels in motor vehicles has been increasing. With the increase in the Town s population and this national increase in average trip distance, the total crash rate per vehicle miles traveled is estimated to be decreasing. - The total number of fatalities dropped by 100% over the five-year period. - The total number of injuries dropped by 56% over the same five-year period. The total injury rate per 1,000 people dropped by 67%. Total Reported Crashes, Reported Year 14

19 ANNUAL TRENDS (Continued) Total Fatalities, # Fatalities Year Total Persons Injured, Injured Persons Year 15

20 ANNUAL TRENDS (Continued) Total Crash, Fatality, and Injury Rates per Population Rate (#/1,000 pop.) Crash Rate Fatality Rate Injury Rate

21 ROAD & INTERSECTION SAFETY One important goal from this accident data is to identify locations where the road environment may be a contributing factor to accidents. This is possible through statistical analysis. Through a statistical analysis of signalized intersections, the following intersections have been identified as the candidates where improvements to the intersection may be beneficial to reducing accidents: Intersection Ownership Agency 1. SH 86 & Crowfoot Valley Dr CDOT 2. SH 86 & Fifth St CDOT The roadway environment is something that is out of the driver s control. Part of the mission of the Town s Traffic Engineering and Operations Division is to assist with minimizing the number of roadway hazards that exist on Town roads that could contribute to accidents. The goal in this regard is to identify locations where roadways could be a contributing factor and implement treatments to correct these. The definition of the safety of a road section or intersection that the Traffic Engineering and Operations Division uses is the number of accidents expected to occur at these locations during a specified period. Because there are factors that are not related to the physical roadway that contribute to accidents, road sections and intersections are expected to have accidents occur. Since what is expected cannot be known, safety can only be estimated, and estimation is in degrees of precision. The precision of an estimate is usually expressed by it s standard deviation. For practical reasons Traffic Engineering is interested in the safety of a road section or intersection that either requires attention because it seems to have too many accidents, or merits attention because it has fewer accidents than expected. In both cases, were the estimation of safety to be based only on accident counts or accident rates, the estimate would be biased. The existence of this regression-to-mean bias has been long recognized. It is known to produce inflated estimates of countermeasure effectiveness. To estimate roadway safety, Traffic Engineering utilizes the Empirical Bayes (EB) method. This method increases the precision of the estimates and corrects for the regression-to-mean bias. The EB method recognizes that accident counts or rates are not the only clue to safety. Another clue is in what is known about the safety of similar entities. To identify the safety of similar entities, safety performance functions (SPFs), which are models, need to be developed from existing data (accidents, vehicle volumes, etc.). SPF models from other jurisdictions can also be adopted if these SPFs are found to fit the Town s local trends. The refinement of SPFs increases as more data becomes available. Traffic Engineering is striving to develop effective SPFs for signalized intersections, roadway segments, and nonsignalized intersections in order to provide for a full toolbox for identifying safety issues. This is important not only to identify locations with potential safety issues, but also to ensure that limited resources are not exhausted on problems that may not exist. 17

22 The Traffic Engineering accident database is still in it s infancy and does not yet have an adequate number of historical records to develop SPFs for street segments and non-signalized intersections. This is normal as jurisdictions try to develop these SPFs due to the fact that the majority of accidents tend to occur at intersections with higher vehicle volumes associated with traffic signals. As the Town s Traffic Engineering Division collects more accident records and continues to develop these SPFs, locations that seem to stand out as having a high accident rate will be looked into closer to determine if any accident trends are occurring that may indicate an issue that should be further examined. A SPF has been developed for signalized intersections within the Town. This SPF provides an indication of the average number of accidents that are expected at similar signalized intersections. This combined with the actual accident records of each signalized site allows for a more precise safety estimate of each signalized intersection utilizing the EB method. The estimates improve with increased annual records. The following tables are safety summaries of 10 signalized intersections with high accident rates for 2008: Table 1: Intersections with 4-year accident histories Intersection 4-Yr Reported Avg. Expected at Similar Locations 4-Yr Expected At Site Standard Deviation Indication of Possible Intersection Issue? Meadows/Factory Shops No SH 86/Allen Wy No US 85/Meadows Pkwy No SH 86/Front St No Meadows/Prairie Hawk No Table 2: Intersections with 3-year accident histories Intersection 3-Yr Reported Avg. Expected at Similar Locations 3-Yr Expected At Site Standard Deviation Indication of Possible Intersection Issue? SH 86/Crowfoot Valley Yes Wilcox/Wolfensberger No Plum Creek Pkwy/Perry No 18

23 Table 3: Intersections with 2-year accident history Intersection 2-Yr Reported Avg. Expected at Similar Locations 2-Yr Exp. At Site Standard Deviation Indication of Possible Intersection Issue? SH 86/Fifth St Yes Table 4: Intersections with 1-year accident history Intersection 1-Yr Reported Avg. Expected at Similar Locations 1-Yr Exp. At Site Standard Deviation Indication of Possible Intersection Issue? I-25/Meadows Pkwy No The results of the tables above provides an indication that eight out of the ten signalized intersections are experiencing an accident rate that is consistent with signalized intersections that are similar in nature. The two exceptions are: Intersection SH 86 & Crowfoot Valley Dr SH 86 & Fifth St Ownership Agency CDOT CDOT This information will be passed onto the Colorado Department of Transportation for their use along with intersection accident diagrams to allow for further assessment to determine if any improvements may be beneficial. For the remaining intersections, there is no indication that the roadway environment is causing a problem at these locations. This does not mean however that changes in the roadway environment could not increase intersection safety. However, since these accidents are more likely to be related to vehicle or human factors, spending a lot of resources on the roadway environment to try and increase the safety of these intersections would not likely be cost effective. In summary, everyone that utilizes the public roadway system has a responsibility when it comes to reducing the number of accidents. There are agencies that specialize in certain areas such as police enforcement, communications, education, and engineering that through their combined efforts will go a long way toward increasing the safety of the Town s roads. 19

24 DEFINITIONS The following special terms are used throughout this report, and are provided to clarify the meaning of the data. 1. Accident (or traffic accident): An unintended event involving a motor vehicle that causes death, injury, or property damage. 2. Alcohol Involvement Accident: Any motor vehicle accident in which a driver, pedestrian, or bicyclist had consumed alcohol. 3. Fatal Accident: A motor vehicle traffic accident which causes the death of one or more persons. 4. Hit-Other-Vehicle: A type of collision in which the first harmful event involves a collision between two or more vehicles. 5. Injury: A person sustaining injuries as the result of a motor vehicle traffic accident. This includes victims with the extent of injury of severe wound, other visible injury, or compliant of pain. Victims killed are not included in the injury category. 6. Motor Vehicle: Any motorized (mechanically or electrically powered) vehicle not operated on rails. 7. Other Non-collision: An event during an accident sequence which does not involve a collision with another vehicle or object. Examples include but are not limited to collapse of a bridge, passenger inhalation of gas, or fire and/or explosion within a vehicle. 8. Rollover: An accident in which the overturning of a vehicle was the first harmful event. 9. Type of Crash: The category which best describes the general type of collision which was the first event. 20

2007 TOWN OF CASTLE ROCK MOTOR VEHICLE ACCIDENT FACTS

2007 TOWN OF CASTLE ROCK MOTOR VEHICLE ACCIDENT FACTS 2007 TOWN OF CASTLE ROCK MOTOR VEHICLE ACCIDENT FACTS ACKNOWLEDGEMENTS This report was assembled from data provided by the Castle Rock Police Department