HomeMy WebLinkAboutCrash DataStats
Crash Data (2003-2008)
195 incidents
4 Fatalities
Ped 2004 Wellborn Rd/ Old Main Dr
Bike 2006 College Main & University Drive
Ped 2005 6 btw Harvey and University
Ped 2004 Harvey Mitchell & Raymond Stotzer Parkway
Bike 2003 12
2004 15
2005 19
2006 7
2007 22
85 plus 8 (2008) -93
Avg. 17 pedestrian crashes each year
Avg. l 8 bicyclist crashes each year
Bike Ped Facilities
2002 -approximately 25 miles of bike lanes
2008 -approximately 32 miles of bike lanes
7 miles difference
Lane Proposed -48 miles
Paths Existing -14 Miles
Path Proposed -44 miles
Route Existing -60 miles
Route Proposed -50 miles
Ped 2003 22
2004 26
2005 13
2006 21
2007 18
90 plus 12 (2008) -102
Corridors identified and complete or almost complete
Continuous north/ south connections
Anderson Street/Longmire Drive/Decatur Drive
Welsh Avenue/Victoria Avenue
Road projects -Dartmouth
Arrington Rd
Greenway property
Approx 485 acres
Wolf Pen Creek l .5 miles
Bee Creek l mile -Lemon Tree, Bee Creek Park
Lick Creek and Lick Creek Park 3 miles
Alum Creek - 2 miles
Bee Creek - 4 miles
Carters Creek - 9 miles
/oz
Gulf States Easement - 8 miles
Lick Creek -2.5
Spring Creek - 3
Wolf Pen Creek
Bee Creek Phase l -Bid Oct 291h Award Nov 24 (Bridge /Longmire Striping)
Construction Jan 09 5 months -wrap up around June
Phase 2 May /June TX Dot Review
the 2005 Bike Loop Ph l (Longmire intersection improvements, Longmire bike lanes and
pedestrian bridge over Bee Creek) construction contract goes to council for award on Dec.
l 0.
Sidewalks
l 994 Existing -30 miles
2008 Existing -56 miles
26 additional miles in 14 years
Other plans
Baltimore Maryland -2001
Greensboro, NC -2006
Santa Clara -Non-motorized
Total
16
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313 S COLLEGE
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3900 VICTORIA
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1800 HOLLEMAN DR
1801 HARVEY MITCHELL PW S
1351 EARL RUDDER FW S
~ 2500 CENTRAL PARK LN
313 S COLLEGE AV
3900 VICTORIA AV
COLLEGE MAIN/UNIVERSITY DR
GEORGE BUSH DR/ANDERSON ST
NAVARRO DR/WELSH AV
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313 S COLLEGE
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3900 VICTORIA
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a Bed
date
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page
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task list:
Legend
-g11.GIS.Streets
+ Bike, HITJINJ (2) + Bike, MAJ (58) * Bike, MN (31)
I'
South Carolina Traffic Collision Fact Book 2000 Definitions
DEFINITIONS
Blood Alcohol Concentration (BAC) -The
percentage of a blood sample that is alcohol;
e.g., a BAC of .10 is a sample of blood with
1 part alcohol for every 999 parts blood.
Bus -A motor vehicle designed to transport sixteen
(16) or more persons, including the driver.
Collision -Throughout this publication the terms
collision and traffic collision are equivalent to
the term motor vehicle traffic collision as
defined below.
Driver -An occupant who is in actual physical control
of a transport vehicle, or for an out-of-control
vehicle, an occupant who was in control until
control was lost.
Driver Intention -What the driver intended to do just
prior to the first harmful event and before
executing an evasive maneuver.
Economic Loss -All figures are rounded to the
nearest $100,000. Based on the 1999
National Safety Council Formula which
applies with the following factors:
Each fatality ................................ $970,000
Each incapacitating injury .......... $ 45,800
Each non-incapacitating injury .... $ 15,300
Each possible injury .................... $ 8,700
Each *PDO accident. .................. $ 6,400
Fatal Traffic Collision -Any traffic collision that
results in the death of at least one occupant or
pedestrian as a direct result of injuries
sustained in the collision within 30 days of
the collision date.
First Harmful Event -The first event in a traffic
collision to result in injury or property
damage.
Harmful Event Location -The place, on or off the
roadway, where the first injury or property
damage occurred. This describes the location
of the first harmful event as it relates to its
position within or outside the trafficway.
South Carolina Department of Public Safety
ncapacitating Injury -Any injury, other than a fatal
injury, which-prevents the ·ajured person from
walking, driving or normally continuing the
activities11-e was capable of performing before
the jnj ury occuITed.
Junction -Either an intersection or the connection
between a driveway access and a roadway other
than a driveway access.
Manner of Collision -The identification in a crash of
how the motor vehicle(s) initially came together
in a traffic collision.
Moped -A moped is a speed-limited, motor-driven
cycle, which may be propelled by pedaling.
Mopeds are not considered motor vehicles.**
Motor Vehicle -Any motorized (mechanically or
electrically powered) road vehicle not operated
on rai ls, excluding mopeds, minibikes and
other vehicles not subject to motor vehicle
licensing regulations. These include:
automobiles, bucks, buses, vans and
motorcycles.
Most Harmful Event -The event for an individual unit
involved in a traffic collision that results in the
most severe injury or property damage.
Motor Vehicle Traffic Collision -A transport collision
that ( 1) involves at least one motor vehicle in
transport, in which the unstabilized situation
originates on a trafficway or at least one
harmful event occurs on a trafficway. This
definition excludes any collision on a private
way.
132
on-lncap_acitating Injury -Any injury, other than a
fatal injury or incapacitating injmy, which is
evident to observers at the scene of the collision
in which the injury occurred.
South Carolina Traffic Collision Fact Book 2000 Definitions
DEFINITIONS
Nonjunction -Anything that is not an intersection
or the connection between a driveway
access and a roadway other than a
driveway access.
Occupant -Any person who is part of a transport
vehicle (automobile, bicycle, etc.)
Passenger -Any occupant of a vehicle other than
its driver.
*PDO -An abbreviation for property damage only.
A PDO collision is one with some
property damage but no injuries or
fa tali ti es.
Pedalcycle - A non-motorized vehicle propelled by
pedaling (bicycle, tricycle, etc.). Note: The
pedalcycle pages include all types but
mostly bicycles.
Pedestrian -Any person who is not an occupant as
defined above. Includes persons on foot,
roller skates, and skateboards.
Possible Injury -Any injury that is reported or
claimed which is not a fatal injury,
incapacitating injury or non-incapacitating
lllJUry.
Private Way (Private Property) -Any land other
than a trafficway. This includes parking
lots even if they are designed for public
use. Collisions on private ways are not
included in this publication.
Probable Cause -Refers to the probable cause of
the traffic collision. This is the
presumptive factor that created the
collision situation.
Road -The part of a trafficway which includes
both the roadway and any shoulder
alongside the roadway.
South Carolina Department of Public Safety
Rural Area -Any area which is not within a
defined urban area.
Traffic Collision -Used m this publication
interchangeably with Motor Vehicle
Traffic Collision.
Traffic Unit (Unit) -Any motorized road vehicle
(includes vehicles that do and do not
qualify as motor vehicles in the above
definition), pedestrians, animal drawn
vehicle and animals with human riders.
Trafficway -Any land way open to the public as
a matter of right or custom for moving
persons or property form one place to
another.
Truck Tractor -A motorized vehicle consisting of
a single motorized transport device
designed primarily for drawing.
Unit -Used interchangeably with traffic unit (see
definition above).
Urban Area -An area composed of an
incorporated place of at least 5,000
population along with the surrounding
densely settled areas.
Source for most definitions: Manual on
Classifications of Motor Vehicle Traffic
Collisions, Fifth Edition, published by
the National Safety Council.
**A moped is defined in the South Carolina Code
of Laws, Section 56-1-1710 (1990). In
part, this specifies that the " ... motor is not
to exceed fifty cubic centimeters and
produce not more than one and one-half
brake horsepower which is not capable of
propelling the vehicle at a speed in excess
of twenty-five miles per hour on level
ground.
133
Development of Criteria to Identify Pedestrian
High Crash Locations in Nevada
Quarterly Progress Report
Submitted to
Nevada Department of Transportation (NDOT)
Research Division
1263 South Stewart Street
Carson City, NV 89712
Srinivas S. Pulugurtha
Krishna Kumar K. Vanjeeswaran
Shashi S. Nambisan
Transportation Research Center
Howard R. Hughes College of Engineering
University ofNevada, Las Vegas
4505 S. Maryland Parkway Box 454007
Las Vegas, NV 89154-4007
Telephone: (702) 895-1338
Fax: (702) 895-4401
July 15, 2003
Development of Criteria to Identify High Pedestrian Crash Locations: Quarterly Progress Report
Development of Criteria to Identify Pedestrian
High Crash Locations in Nevada
Nevada has experienced over 40 pedestrian fatal crashes per year over the last six years.
Likewise, Nevada also has experienced over 800 pedestrian injury crashes per year during the
same period. More than 70 percent of these pedestrian fatal crashes and pedestrian injury crashes
are in Clark County, Nevada. There is a critical pedestrian safety issue on many urban streets in
Nevada, in general, and in the Las Vegas metropolitan area in Clark County, Nevada, in
particular. The Las Vegas metropolitan area is ranked among the worst urban areas in tenns of
pedestrian safety. Crashes in such an environment also result in adverse publicity, which can
linger long after the incidents themselves. Besides the adverse publicity, these crashes result in
significant health and human life consequences, and monetary impacts.
The main objective of this research project is to develop criteria to identify "pedestrian high
crash locations" in order to allocate resources including Federal Safety Funds, for safety
improvements . The criteria will help in the development of a "Pedestrian Safety Program'', as a
part of the Nevada Department of Transportation's (NDOT) Federal Highway Safety
Improvement Program (HSIP). The developed criteria will assist the system managers not only
in Las Vegas and Nevada, but also nationally, in better understanding the cause of the crashes
and identifying appropriate operating strategies to enhance pedestrian safety.
The proposed research is divided into the following main tasks:
1. Task 1: Literature Research
2. Task 2: Data Collection and Geocoding
3. Task 3: Analysis of Data
4. Task 4: Develop Criteria to Identify "High Crash Locations"
5. Task 5: Recommendations and Scope for Further Research
6. Task 6: Preparation of Progress Reports, Final Report and Publications
Literature Research
Several analytical tool and techniques are available to analyze crash data.
1
Development of Criteria to Identify High Pedestrian Crash Locations: Quarterly Progress Report
Combination of Statistical Methods
Most GIS packages have very sophisticated database operations. However, they do not have
statistical methods other than means and standard deviations of variables. Therefore, the
statistical spatial method is needed when a more sensitive quantitative method is required
(Levine 1999). Schneider, Khattk, and Ryznar (2002) adopted statistical method on their cluster
analysis in order to integrate and evaluate data from two different sources (crash reports and
survey data). CrimeStat, a spatial statistics software package, was used to perform the cluster
analysis. In addition, several other spatial statistics such as Chi-squared, Ripley's K-function,
and G-function tests were also computed.
In short, pedestrian safety studies involve data collection and spatial analysis. The basic data
needs for this analysis are crash reports, street centerline coverage, and demographic data. The
spatial analyses include use of zone guide for pedestrian safety, and integration statistical
methods with GIS.
Schneider et al. (2001) explains the importance of methods to identify where the pedestrian crash
problem exists so that a greater number of pedestrian crashes can be prevented in the future.
Studies in recent years have focused on the issue of safety analysis using GIS techniques. Even
though GIS techniques are not extensively used in safety field, they have greater potential to
improve crash location evaluation. Several studies have cited the benefits for using GIS to plot
automobile crash locations and identify high-risk areas for motorized-vehicle crashes, though
fewer have applied the technique to analyze pedestrian or bicycle crashes. Simple crash plotting,
or geocoding crash locations, is the most common GIS technique used for safety studies (1). GIS
turns statistical data, such as crashes, and geographic data, such as roads and crash locations, into
meaningful information for spatial analysis and mapping (2). Using GIS it is relatively simple to
combine information received annually on crashes and determines any correlation such as type
of street and adjacent land use. GIS also assists in identifying any factors that were contributing
to those crashes and/or potential solutions to reduce those crashes (3). GIS-based crash data
analysis can influence the four E's of traffic safety: engineering, enforcement, education, and
emergency response ( 4).
2
Development of Criteria to identify High Pedestrian Crash Locations: Quarterly Progress Report
Analyses of Pedestrian Crashes
Pedestrian crashes can be categorized in to three major areas (Baltes 1998). They are:
1. Pedestrian characteristics -which explains characteristics of persons involved in these
crashes (gender, age and ethnicity)
2. Crash types -which explains elements that lead to crashes (for example, alcohol related,
failed to yield the right-of-way and stepped into the path of an oncoming vehicle,
disregarded a traffic signal, or made some improper action that contributed to the crash
like crossing not at intersection, crossing at mid block crosswalk, crossing at intersection,
walking along road with traffic, walking along road against traffic, working on vehicle in
road, standing playing in road, standing in pedestrian island, etc), and
3. Crash event -which explains when and where did these crashes occur (date, time of the
day, day of the week, location (urban or rural), weather and lighting conditions, roadway
number of lanes, road system identifier, and road surface conditions).
This way of categorizing the pedestrian crashes helps develop effective and practical
countermeasures to reduce the pedestrian injuries and fatalities. It is important that crash types
are analyzed for different pedestrian age groups. For example, studies have shown that alcohol
impaired pedestrian problem is high among some racial and ethnic groups which points to
another set of characteristics to be analyzed (NHTSA 1998; Leaf and Preusser ).
Analysis based on the number of pedestrian crashes in a particular age group, ethnicity, or
gender group is useful, but insufficient for determining whether a specific group is more or less
prone to be in a crash. This can only be obtained by considering crash rate per capita (from
census data) and crash rate per kilometers walked (from Nation Wide Personal Transportation
Survey, NTPS information). These crash rates by different age groups will show which age
group are most likely to involve in a crash.
Analysis of crashes based on severity is another critical element. Higher vehicle speeds are
strongly associated with both a greater likelihood of pedestrian crash occurrence and more
serious resulting pedestrian injury (Leaf et al. 1999; IIHS 2000).
3
Development of Criteria to Identify High Pedestrian Crash Locations: Quarterly Progress Report
The population density is not a good replacement for pedestrian exposure as it does not account
for the amount of walking people do (Qin and Ivan 2001 ). The number of lanes, area type and
sidewalk system are some of the factors that affects the pedestrian exposure.
Crash studies are generally based on reported crash records. Schneider, Khattk, and Ryznar
(2002) state that reported crash data alone may not be a good predictor of future crash locations,
especially for infrequently -occurring pedestrian crashes. To solve this problem, Schneider,
Khattk, and Ryznar presented the idea of combining the crash data with perception survey
method. The study concluded that perception survey data helps improve site selection and
recommendations for pedestrian safety treatment (for example, gather large quality of data about
locations that may have pedestrian problems, and study differences in the perceptions of people
with specific traits). However, surveying method may not be appropriate for large study areas
such as city or metropolitan areas as it is a time consuming and expensive process.
Braddock et al. (1994) identifies two high pedestrian crash locations which account for 30
percent of all pedestrian crashes in Hartford County, Connecticut based on address matched
crash data for analysis (15).
Tools and Techniques
Several analytical tool and techniques are available to analyze crash data. However, questions
such as "where are most of the crashes occurring and why?" is difficult to answer. These
questions can be easily achieved in a GIS environment. Using GIS to geocode crash locations
and plot the locations is the most common first step (Anadaluz, Robers, and Tina 1997). In order
to ensure a reasonable stable measure, experience has shown that a minimum of one year's data
or at least 100 crash records should be available for establishing pedestrian safety zones
(NHTSA, 1998). For data analysis, various techniques were used to create zones, identify
hotspot locations, and rank the study locations.
NHTSA (1998) recommended the guide to identify study zones for pedestrian safety. The zone
process provides a systematic method for targeting pedestrian safety improvements in a cost
effective manner. Zoning identifies a subset of a jurisdiction containing as much of the
4
Development of Criteria to identify High Pedestrian Crash Locations: Quarterly Progress Report
pedestrian problem of interest in as little land area as possible. The first step is to select an initial
shape for the zones and to define the target rate i.e., the number of events that must fall in an area
for it to be defined as a zone. The approach suggested is to search for circular zones, then to
search for linear zones, then to determine their final shape. The initial circular zones could be
created by using one mile radius, as generally pedestrian crashes occur within one mile of the
victim's home or work place. Risk zones could be identified using a target rate of 10 crashes per
zone for total 200 crashes data. For linear zones, it could be determined for the segments where
six or more crashes occur in a two miles for total 200 crash data. In addition, if total crash data
that are used in analysis is higher, the target rate should be adjusted upward as necessary. The
final step is to identify the final zone shape, as it may be useful to combine zones, add more
radiuses, change zones' shape, or reduce zones' size. Finally, to define zones, areas with some
clustering and some dispersion throughout a land area should be identified. However, such a
methodology may not work if no clustering is apparent in the study area.
A few GIS based studies are briefly discussed next. Braddock, Lapidus, Cromly, Burke, and
Banco (1994) identified two high pedestrian crash locations which account for 30 percent of all
pedestrian crashes in Hartford County, Connecticut based on address matched crash data for
analysis. In a different context, three-mile buffer zones were created around 3 clustered areas
using GIS to study moped safety in Hawaii. The temporal variations, environmental
characteristics, and crash characteristics of these spatially distributed moped crashes were then
studied (Kim, Takeyama, and Nitz 1995).
A GIS based crash analysis tool developed by FHW A (1999) uses five different types of analysis
to evaluate crashes. The Spot/Intersection Analysis program is used to evaluate crashes at a user-
designated spot or an intersection within a given search radius. The Strip Analysis program is
used to study crashes along a designated length of roadway as opposed to a spot or an
intersection. The Cluster Analysis program is used to study crashes clustered around a given
roadway feature such as a bridge, railroad crossing, or traffic signal. The Sliding-Scale Analysis
program is used to identify roadway segments with a high crash occurrence. The Corridor
Analysis program is used to locate high crash concentrations within a corridor. Using traditional
5
Development of Criteria to Identify High Pedestrian Crash Locations: Quarterly Progress Report
methods, segments along a specific route could be examined, but multiple routes within a
corridor could not be easily linked and analyzed as a group, which is possible using this tool.
A simple method, called nearest neighborhood analysis, was used to identify hot spot locations in
a mid-block pedestrian safety study (Cui 2000) The analysis used grid cells with a dimension of
100 feet per site and a circular radius of 500 feet. The resultant scores were grouped and ranked
based on the distribution of number of pedestrian crashes.
Steiner et al. (2002) discusses about three steps for developing GIS crash mappmg: (1)
identification and collection of data (both crash data and the map data layer); (2) selection of a
program for processing of crashes; and (3) analysis of data collected by the system.
Identify High Crash Locations
One of the most common macroscopic applications of GIS is the determination of high crash
locations, HCLs (Roche 2000). HCLs identify the areas that would potentially receive the largest
benefit if safety funds were allocated. These locations can be analyzed in many different ways.
One method of HCL identification includes crashes within a specified distance of a major
roadway. Another method determines the crash frequency within a specified distance. One of the
drawbacks of identifying locations with high crash frequencies is that traffic volume or exposure
is not taken into account. This can be accomplished by the crash rate method. The crash rate
method for roadway segments divides the total number of crashes by the annual average daily
traffic (AADT) and the length of the segment to obtain crashes per vehicle miles traveled.
Cui (2000) used nearest neighborhood analysis, to identify hot spot locations in a mid-block
pedestrian safety study. The study used grid cells with a dimension of 100 feet per site and a
circular radius of 500 feet. The resultant scores were grouped and ranked based on the
distribution of number of pedestrian crashes.
South East Michigan Council of Government (SEMCOG) Crash Analysis Manual (SEMCOG
2001) explains five ways of locating high crash locations. Spot map method_,_ the simplest method
of identifying high-crash locations, is to examine a map showing clusters of symbols at those
6
Development of Criteria to JdentifY High Pedestrian Crash Locations: Quarterly Progress Report
spots and on those segments in the road network having the greatest numbers of total crashes.
Crash Frequency Method is a method to rank locations by the number of reported crashes (or
crashes per mile), with frequencies listed in descending order. Locations having crash
frequencies greater than or equal to a critical crash frequency are considered to be high-crash
locations. Crash Rate Method ranks locations by descending crash rate. Locations with above-
average rates are tested for significance. The Crash Rate Method compares the number of
crashes to the volume of traffic, with the later measured either as the number of vehicles crossing
a spot in a given time period, or as the number of vehicle-miles of travel along a segment in that
period. In Crash Severity Method, crash frequencies or rates are weighted by severity whereas in
the Crash Probability Index (CPI) Method frequency, rate, and severity results are combined.
The Crash Rate Method used to find HCLs is a simple statistical test to detennine whether the
crash rate for a particular location is significantly higher than the average crash rate for other
locations in the jurisdiction having similar characteristics. If the crash rate is higher than the
average crash rate, the location is classified as a high-crash location. The steps involved in this
method are as follows.
1. Detennine the location's crash rate. The spot crash rate is found as annual average
number of crashes during the study period divided by the average daily traffic volume
during the study period in crashes per million vehicles. The segment crash rate is found
as spot crash rate divided by length of segments in crashes per million vehicles per miles.
2. Define the location type. Categorize the location by as many of the following features as
possible: area type, roadway functional class (arterial, collector, or local), number of
lanes, etc.
3. If a list of previously evaluated locations is being maintained, insert the location into the
list of locations ranked in descending order by crash rate
4. Determine the critical crash rate.
5. Compare the location's crash rate to the critical crash rate. If the crash rate equals or
exceeds the critical crash rate, classify the location as a high-crash location.
7
Development of Criteria to identify High Pedestrian Crash Locations: Quarterly Progress Report
Iowa Department of Transportation, Office of Traffic and Safety (OTS IDOT 2001) describe the
advantage of using crash rate in comparing the crash experience between different time periods
or between locations. This provides a basis for more accurate and meaningful conclusions since
it accounts for the numbers of vehicles "exposed" to the hazards of driving within a given time
period. It also prevents the potentially misleading classification of a relatively safe high-volume
location as "high-crash" simply because it has experienced a relatively large number of crashes.
However, it tends to unfairly identify low-volume locations having relatively few crashes as
high-crash locations.
Data Collection and Geocoding
Digitizing crashes on a digital map with street network is not only inaccurate but a time
consuming process. On the other hand, the process of automatically creating map features based
on address, or similar infonnation exploring the capabilities afforded by GIS software is called
geocoding. Crashes can be geocoded using one of the three reference systems (street name I
reference street name, mile-post and address). The street name I reference street name reference
system and address are most commonly used in urban areas. The advantage of geocoding is that
it lets one map locations from crash data that is readily available.
However, a street network in a GIS format with street name and address information is extremely
important to geocode crash data. Street centerline (SCL) network in a GIS format are generally
developed by public and private agencies. A few of these are commercially available. SCL
network attributes include street name, street type (Avenue, Boulevard, and so on), and
directional prefixes and suffixes necessary to avoid ambiguity in address location. Each street
feature is divided into segments that have beginning and ending addresses, as you see on
neighborhood street signs. This makes it possible to estimate the position of an address along the
length of a street segment. There may be separate address ranges for each side of the street, so
that an address can be geocoded on the correct side of the street.
The Transportation Research Center, UNL V has the SCL coverage for the Clark County
developed and maintained by the Clark County Department of Public Works GIS Managers
Office (GISMO). The SCL coverage for the Clark County has 61 ,573 street segments. Street
8
Development of Criteria to Identify High Pedestrian Crash Locations: Quarterly Progress Report
name and address information is available for all these streets. However, data is not available for
other counties in Nevada. A search was conducted to obtain data from other sources. The other
common sources for the street network data are: 1) Tiger/Line data from the United States
Census Bureau, 2) Geographic Data Technology (GDT) Dynamap U.S Street Data, and 3) Tele
Atlas MultiNet.
Census 2000 TIGERJLine data can be downloaded in a shapefile format from United States
Census Bureau website free of cost. For the state of Nevada TIGER/Line data contains 345,124
street segments out of which 157,355 are named street segments (45 .6%).
GDT Dynamap/2000 United States Street Data can be purchased online in variety of formats
including the shapefile fonnat. For the state of Nevada Dynamap/2000 data contains 446,844
street segments out of which 238,716 are named street segments (53.4%). The cost for a 1-5 user
internal license, for the state of Nevada, perpetual use of the data, for Dynamap/Transportation is
$10,500.00 and a 1-5 user internal license, annual use of the data, is $7,875.00.
Tele Atlas, a private provider of digital maps, offers a product called Tele Atlas MultiNet which
is has 40,000 street network segments for the state of Nevada out of which 38,000 are named
segments. The cost for up to 5 users of the Tele Atlas MultiNet product in a shapefile format for
use on PCs is $7,030.00 without driving directions (routing attributes). With routing attribute
infonnation the cost is $14,440.00.
The number of street segments and percent of named street segments in TigerLine data and GDT
databases for each County in the State of Nevada are summarized in Table 1. As can be seen
from the table, percentage of named street segments is less than 70 percent for most of the
counties in the State of Nevada. This might limit the number of crashes that could automatically
be geocoded using GIS software. Though, GDT has more percent of named street segments, it is
expensive compared to Tiger/Line data which is available free of cost.
9
Development of Criteria to Identify High Pedestrian Crash Locations: Quarterly Progress Report
TABLE 1 Number of Street Segments and Segments with Street Name by County
County No. of Street Segments % of Named Street Segments
Ti!!er/Line GDT Ti!!er/Line GDT
Clark 75,072 108,735 85.4 95.8
Carson City 4,785 6,560 81.7 90.4
Washoe 34,122 54, 110 69.9 78.8
Douglas 7,732 8,211 66 87
Lyon 10,991 14,332 56.9 59.1
Storey 1,947 2,053 42.3 50.7
Churchill 12,736 15 ,860 33.3 34.6
Nye 41 ,824 53 ,144 30.8 34.3
Elko 41,870 47,038 26.9 24.9
Eureka 7,096 9,746 25.2 39.1
White Pine 26,095 31 ,624 24.8 25 .3
Humboldt 19,809 20,431 24.4 35
Mineral 10,573 13 ,178 22.6 22.1
Lander 11 , 150 11 ,505 19.6 25 .6
Pershing 13,787 18 ,176 18.7 24.9
Lincoln 17,617 22 ,157 18.6 14.1
Esmeralda 7,918 9,984 17.7 14.2
Total 345,124 446,844 45.6 53.4
PROGRESS
As of June 30 2003 Task 1 has been completed. In the next quarter (July 1 -September 30,
2002), activities will include working on Task 1 and Task 3. This will include 1) collection of
street network data for Clark County, Carson City, Washoe County, Douglas County and Lyon
County, 2) geocode crash data subject availability of street network, and 3) analyze crash data.
REFERENCES
1. Schneider, R.J., A. J. Khattak, and C. V . Zegeer (2001) Method of Improving Pedestrian
Safety Proactively with Geographic Information Systems. Transportation Research Record
1773, pp 97-107.
2. FHW A (2000) GIS Tools for Improving Pedestrian & Bicycle Safety. TechBrief, FHW A-
RD-00-153 , Federal Highway Administration (FHWA), U.S. Department of Transportation
(U.S. DOT).
3. Walgren, S. (1998) Using Geographic Information System (GIS) to Analyze Pedestrian
Accidents. CD-ROM, 681h Annual Meeting of the Institute of Transportation Engineers.
10
Development of Criteria to identify High Pedestrian Crash Locations: Quarterly Progress Report
4. Roche, J. (2000) Geographic Information Systems-Based Crash Data Analysis and the
Benefits to Traffic Safety. Transportation Scholars Conference, Iowa State University, Ames,
pp 85-94.
5. NHTSA (1998) Zone Guide for Pedestrian Safety Shows How To Make Systematic
Improvements. Traffic Tech, Issue 181 , HS-042 731 , National Highway Traffic Safety
Administration (NHTSA).
6. Baltes, M. R. ( 1998) Descriptive Analysis of Crashes Involving Pedestrian in Florida, 1990-
1994. Transportation Research Record 1636, pp 138-145.
7. USDOT (1998) The Alcohol Impaired Pedestrian Problem is High Among Some Racial and
Ethnic Groups. DOT HS-042 667, U.S. Department of Transportation (U.S. DOT), National
Highway Traffic Safety Administration.
8. Leaf, W. A., and D. F. Preusser(). Racial/Ethnic Patterns among Pedestrian Alcohol Crash
Fatalities. Preusser Research Group, Inc., Trumbull, Connecticut, USA.
9. Leaf, W.A., and D. F. Preusser (1999) Literature Review on Vehicle Travel Speeds and
Pedestrian Injuries. DOT HS-809 021: Final Report, U.S. Department of Transportation
(U.S. DOT), National Highway Traffic Safety Administration.
10. llHW (2000) In Pedestrian Crashes, It's Vehicle Speed That Matters the Most. Status Report,
Vol. 35, No. 5, May 13, Insurance Institute for Highway Safety (IIHS).
11. Qin, X., and J. N. Ivan (2001) Estimating Pedestrian Exposure Prediction Model in Rural
Areas. Transportation Research Record 1773, pp 89-96.
12. Schneider, R. J., A. J. Khattak, and R. M. Ryznar (2002) Factors Associated with Pedestrian
Crash Risk: Integrating Risk Perceptions and Police-Reported Crashes (Paper No. TRB 02-
2706). 2002 Annual Transportation Research Board Meeting, Pre-print CD-ROM.
13. Andaluz, D., T. Robers and S. Siddall (1997) GIS Adds A New Dimension to Crash
Analysis. Journal of the Urban and Regional Information Systems Association, Vol. 9, No. 1,
pp. 56-59.
14. Braddock, M., G. Lapidus, E. Cromley, T. Cromley, G. Burke, and L. Banco (1994) Using a
Geographic Information System to Understand Child Pedestrian Injury. American Journal of
Public Health, Vol. 84, No. 7, pp.1158-1161.
15 . Saxena, A., G. Babu, R. K. Bajpai, and SM. Sarin (2002) GIS as an Aid to Identify Accident
Patterns. Map India 2002 Proceedings, GIS Development, The Asian GIS Monthly.
11
Development of Criteria to Identify High Pedestrian Crash Locations: Quarterly Progress Report
16. Kim, K., D. Takeyama, and L. Nitz, L (1995). Moped Safety in Honolulu Hawaii. Journal of
Safety Research, Vol. 26, No. 3, pp. 177-185.
17. USDOT (1999) GIS-Based Crash Referencing and Analysis System. HSIS Summary Report,
FHWA-RD-99-081, FHWA, U.S. Department of Transportation (U.S. DOT).
18. Cui, Z (2000) GIS-based Evaluation of Mid block Pedestrian Crossing Safety. M.S. Thesis,
Department of Civil & Environmental Engineering, University of Nevada, Las Vegas.
19. Steiner, R. L., R.H. Schneider, and J.M. Moss (2002). The Promise and Perils of Pedestrian
Crash Mapping: A Study of Eight Florida Counties. 2002 Annual Transportation Research
Board Meeting, Pre-print CD-ROM.
20. SEMCOG (2001) Southeast Michigan Council of Government (SEMCOG) Crash Analysis
Manual. Office of Traffic and Safety, Iowa Department of Transportation, 2001.
21. OTS IDOT (2001) Iowa Data and Analysis. Office of Traffic and Safety (OTS), Iowa
Department of Transportation (IDOT), 2001 .
12
date
project
page
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\ ,"' '
FHWA GIS High Crash Zones Tools
Version 4.0
User Guide
Prepared for
Federal Highway Administration
Office of Safety Research and Development
6300 Georgetown Pike, T-203
Mclean, VA 22101-2296
By
I lfJl3 llinasse Haugen BrustHn, Tnc_. __
101 Walnut St
P.O. Box 9151
Watertown , MA 02471-9151
Vanasse Hangen Brustlin, Inc.
Table of Contents
Introduction ................................................................................................ 1
Requirements ............................................................................................. 1
Installation .................................................................................................. 1
Microsoft .Net Framework v1 .1/2.0 ........................................................................................... 1
ArcGIS .Net Support .................................................................................................................. 1
Application ................................................................................................................................. 1
Execution .................................................................................................... 2
Functionality ............................................................................................... 3
Display ....................................................................................................................................... 3
Display Layer ......................................................................................................................... 3
Analysis ..................................................................................................................................... 4
Create Density Grid ............................................................................................................... 4
Create a High Crash Zone ..................................................................................................... 7
Selecting Crashes in a High Crash Zone ............................................................................... 8
Report .................................................................................................................................. 10
Map Template ...................................................................................................................... 10
ADM Setup .......................................................................................................................... 11
Database Connection .......................................................................................................... 11
Appendix A -New Project Setup ............................................................ 13
Initialization .............................................................................................................................. 13
Data Reference ....................................................................................................................... 13
Feature Classes ................................................................................................................... 14
Tables .................................................................................................................................. 14
Layers .................................................................................................................................. 14
Initialization Parameters ...................................................................................................... 15
Appendix B -ADM Setup ........................................................................ 16
1 -ADM Setup ........................................................................................................................ 17
2 -ADM Environment ............................................................................................................. 17
3 -ADM SOL .......................................................................................................................... 17
4 -ADM SOE .......................................................................................................................... 18
5 -ADM Feature Class ........................................................................................................... 19
6-ADM Table ........................................................................................................................ 21
7 -ADM Layer ........................................................................................................................ 23
8 -ADM Layer Related ........................................................................................................... 24
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FHWA GIS High Crash Zones Tools v4.0
Introduction
This document provides basic Installation and Execution instructions for the FHWA GIS High
Crash Zones Toolbar Version 4.0 ArcGIS v9.1 or greater.
Requirements
For this extension to work, at a minimum, the following software must be installed on the local
computer:
• Microsoft .Net Framework (v1 .1 or 2.0);
• ESRI ArcGIS 9.1 (sp2) or 9.2 -(both with .Net Support)
• ESRI Spatial Analyst Extension; and ,
• Crystal Reports version XI for ESRI.
Installation
Microsoft .Net Framework v1. 112.0
The Microsoft .Net Framework is a software component which can be added to the Microsoft
Windows operating system. It provides a large body of pre-coded solutions to common program
requirements, and manages the execution of programs written specifically for the framework.
If necessary, the Microsoft .Net Framework redistributable package can be downloaded directly
from the Microsoft website. Follow the instructions on this page on how to install the package.
ArcG/S .Net Support
In ArcGIS 9.1, .Net Support is not installed by default, so the user must select it as a custom
installation option during install. If ArcGIS 9.1 is already installed and does not have .Net
Support installed, run the ArcView Setup, select 'Modify' the installation and then select '.Net
Support'.
In ArcGIS 9.2, the .Net Support option is installed by default providing the ArcGIS installation is
performed on a machine with .Net Framework 2.0 installed .
Application
To install the FHWA GIS High Crash Zones Tools application:
Support Libraries
1. Download the installation package 'vhblibraries.msi' from the FHWA website.
2. Double-click the 'vhblibraries.msi' installation package. An installation wizard will start to
perform the installation. Follow the instructions. Several support library files will be
installed in to [Program Files]\VHB\Common (i.e., C:\Program Files\VHB\Common').
Tool bar
1. Download the installation package 'setuphcz.msi' from the FHWA website.
2. Double-click the 'setuphcz.msi' installation package to install the main application toolbar
and project components. An installation wizard will start to perform the installation.
Follow the instructions .
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FHWA GIS High Crash Zones Tools v4.0
Several files will be installed in the application destination directory (i.e., c:\Program
Files\FHWA\HCZ'):
1. HCZADM.mdb. A blank application database. The database can be copied and
modified to reference project-specific data.
2. HCZ.mxt. A pre-defined Map template.
3. FHWA GIS High Crash Zones Tools v4 User Guide.
4. ADM v2 Data Dictionary.
The main application file (FHWAHCZ.dll) is installed in the Common files folder (i.e., c:\Program
Files\ VHB\Common ).
Execution
To open ArcGIS with the FHWA GIS High Crash Zones toolbar, either:
1.
2.
3.
Or:
1.
2.
3.
Open ArcMap.
Select 'File -7 Open ... '. Using the File Dialog, select the ArcGIS Project (i.e.,
'c:\HCZ\HCZ.mxd').
ArcGIS should open and load the Project.
Navigate to the appropriate Project folder (i.e., 'c:\HCZ).
Double-click the ArcGIS Project (i .e., 'c:\HCZ\HCZ.mxd').
ArcGIS should open and load the Project.
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FHWA GIS High Crash Zones Tools v4.0
Functionality
The following functionality was implemented as part of the High Crash Zones Tools application
v4.0.
Display
Display Layer
This tool allows any of the Layers or Tables defined within the ADM Database to be opened and
inserted into the current ArcGIS Project.
1. Click the 'Display Layer' tool on the 'FHWA HCZ Analysis' toolbar.
2. A Dialog is displayed showing all of the defined Layers and Tables in a Tree View.
1$1 Crashes
Crashes
, · High Cr ash Zones
$ Drthos
itJ Rail
El Road
1 :24.000 Scale Road Coverage
·· Aver age Daily Traffic
·llllml
··· Intersections
Pavement Condition
Route and Milepost Nodes
Routes
Signal Inventory
Universe File
1±1 Table
Add
Figure 1
.:.]
Close I
3. Select the Layer/Table to open and press the 'Add ' button. The selected Layer/Table will
be opened and inserted into ArcMap.
4. Repeat step 3 until all of the required Layers/Tables have been opened.
5. To exit from the Dialog, press 'Close'.
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FHWA GIS High Crash Zones Tools v4.0
Analysis
Create Density Grid
The 'Create Density Grid' tool is used to create a density Grid based on selected Crashes and
defined search radius.
1. Click the 'Create Density Grid ' tool on the 'FHWA HCZ Analysis' toolbar.
2. If it does not already exist in the map, the 'Crashes' Layer will be automatically loaded.
3. A Dialog is displayed allowing for the parameters for Grid Creation to be entered:
a. Crash Selections -Use either of the two native ArcMap tools provided, both
accessible via buttons on the 'Create HCZ Grid' form. The first button activates
the spatial selection tool, which enables the Crashes to be selected directly on
the map. The second tool activates ArcMap's native 'Select by Attributes' tool.
For a more detailed description of the 'Select by Attributes' tool , see the
description at the end of this section.
b. Any time the Crash selection is changed after the tool is active, the Crash
Selections counts will be updated on the form.
c. Search Radius -The search radius distance is used to search from each cell in
the output grid layer for points (crashes) to be used in the density calculation .
The distance is reported in the map units specified for the map's data frame.
Create HCZ GRID
Crash Seleclions 13371 1337
Sear ch Radius (M elers)
OK Cancel
Figure 2
Once Crashes are selected and the Search Radius entered , press 'OK'.
Note: The user needs to remember the search is for selected crashes. If no Crashes
are selected then all Crashes in the view will be selected in the creation of the
Density Grid .
4. The Density Grid is created and the following occurs:
a. A Group Layer is created and named 'Analysis' [Number], where [Number] is the
number of the Analysis performed during the current session (as long as ArcMap
is open).
b. The Crash selections are added to the Analysis Group Layer named 'Selected
Crashes'.
c. A new Grid raster layer is added to the map in the format "Crash/[scaled unit]2
Grid [SearchRadius][unit] SR" (i.e. Crash/km2 Grid 800m SR). The layer is
classified in to nine classes with equal breaks, from lowest to highest density.
Note: SR='Search Radius'
d. The Density Grid and map will appear as follows:
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FHWA GIS High Crash Zones Tools v4.0
@ layers
El ~ Analysis 1
H ~ Selected Cr ashes
+ '" FJ ~ mmmwpm !Ni lf)I
<VALUE> f'j +
O o-5.389
0 5.389-10.778
Cl 10.778-16.167
11116.167 -21.556
•21.556-26.946
• 26.946 -32.335
.32.335-37.724
.37.724-43.113
• 43.113 -48.502
d ~ Crashes
0
H ~ Roads 1
. .. • •
.=:D::;:isp:::'lay'==So:::ur:::ce:'.==Se:::lec:::tio::'n :__ _ _J___J ._ Cl ~ 11 ..!J
+ • + • • ...
~ .... * •
• J + • •
-f •
• + •
......
I ,636.52 226.80 Kilometers r-
Figure 3
Note: When a Group Layer is created , a corresponding folder is created in the 'Output' folder
contained at the same location as the containing ArcMap document (.mxd). The folder
name corresponding to the Analysis being performed is in the following format:
'Analysis[Number][Month][Day][Year][Time]'
For example, 'Analysis 112052007711 '.
The shape files generated during an Analysis (Crash Selections and High Crash Zones)
will be written to this folder. The Grid is created in a temporary ESRI Geodatabase for
performance reasons. The Grid layer can be saved for later use if desired.
Note: For a detailed description How the Kernal Density works, refer to the ArcGIS Desktop
Help, in the Spatial Analyst tools section.
Select by Attributes
When the 'Select by Attributes' tool is selected (either from the main ArcMap menu or the
•Create HCZ Grid form), a Dialog is displayed enabling the selection of features by attributes:
1. Make sure 'Crashes' layer is selected.
2. Select 'Method' for selection. In most cases 'Create a new selection' will be used to
create a brand new selection. There may be cases where the user wants to filter or add
to a current selection, and these options are also available here.
3. Create the query based on the query builder provided. For more information on how to
build queries, please refer to the 'ArcGIS Desktop Help'.
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FHWA GIS High Crash Zones Tools v4.0
!,ayei: I Crashes :::J
r !lnl.Y show selectable layers in this fist
Met hod: I Create a new selection ::::J
"ACCSEV" ~I
"MOPED"
"BIKE"
"HIT RUN"
'YRCASE"
'YEAR" "I
SELECT •FROM 93to96 l'!'HERE:
I "'~ _,
Cl.§ar Verif.I! !:felp Loa.fl ... I Saye ... I -
OK 8pply I ];;lose I
Figure 4
4. The selections should show on the map. The selection count is updated accordingly on
the Create Density Grid form.
Note: In the Density Grid Creation methodology, a simple density grid is a circle drawn around
each grid cell center using a radius and the number of points that fall within the circle is
totaled and divided by the circle's area. The HCZ, instead of creating a simple the
density crash grid, uses a kernel function for density estimation. A kernel is a smoothly
curved surface fitted over each point. Its value is highest when you are right on the point,
and this diminishes as you move away from the point, reaching 0 at the radius distance
from the point defined by the search radius. The density at each output grid cell is
calculated by adding the values of all the kernel surfaces where they overlay the grid cell
center.
Note: Being able to change the search radius gives the user the ability to determine crash
zones from the county-wide to neighborhood scale and it also enables the user to
identify areas or corridors of high crash occurrence. The larger the search radius the
better visually areas of high crashes will appear at smaller scales such as a county or
multi-county displays. Also, with the larger search radius the user will have a better
ability of finding areas or regions of high crash occurrence. Smaller radii are more suited
for identifying high crash zones in corridors or intersections and at larger scale displays.
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FHWA GIS High Crash Zones Tools v4.0
Create a High Crash Zone
Once a Density Grid Layer has been created, the High Crash Zone Tool can be used to create
the High Crash Zone. What constitutes the area of a High Crash Zone is dependent on the
user's requirements, so the user has the option to select any 'size' Crash Zone, represented as
a percentage between 1 and 100. Each grid cell has a value representing the output from the
Kernal Density calculation (represented as Crash/[scaled unit]2 . The percentage is based on
the grid cell value representing the highest concentration of crashes.
As an example, if the maximum value for any cell in the grid is 48.502 (as represented in Figure
5 below), the percentage is based off of the value 48.502, so entering a percentage value of
50% would return 24.25. The High Crash Zone then would represent an area where the grid
cells are equal to or greater than 24.25.
To create a High Crash Zone,
1. Select the Density Grid Layer from which to produce the High Crash Zone. Selecting a
Density Grid Layer will activate the 'Create High Crash Zone' tool on the toolbar
(selecting the Analysis group layer will not activate the 'Create High Crash Zone' tool);
El @ Layers
-~ Analysis 1
'=J ~ Selected Crashes
4 -'] ~ lli~B&ii£1
<VALUE>
D o-5.389
0 5.389-10.778
D 10.778-16.167
16.167 -21.556
• 21.556 -26.946
•26.946-32.335
• 32.335 -37.724
• 37.724 -43 .113
• 43.113 -48.502
Figure 5
2. Click the 'Create High Crash Zone' tool on the 'FHWA GIS HCZ' toolbar.
3. A Dialog is displayed allowing for the percentage value to be entered:
a. Zone Density (Minimum %)-Enter a value between 1 and 100 to indicate the
minimum percentage of Crashes/km2 to use .
.. . ·. .... .. ...
Zone Densit_y [%) 15Q
(%of max grid eel! y.afi;-.,=48. 502/
OK Cancel
Figure 6
Once the Density percentage is entered, press 'OK'.
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. .
FHWA GIS High Crash Zones Tools v4.0
4. A High Crash Zone layer is produced with the name "Crash Zone: SR > [percentage)"
(Example: "Crash Zone : SR > 50%").
Note: SR='Search Radius'
The results appear as follows:
@ Layers
~ Analysis 1
1::1 ~ Selected Cr ashes
+
H ~ Crash Zone: SR> 50%
[J
Cr a<h/km2 Grid 500m SR
<VALUE>
o o-5.389
0 5.389 -10.778
0 10.778 -16.167
Iii 16.167-21.556
.21.556-26.946
.26.946 -32.335
.32.335-37.724
.37.724-43.113
• 43.113 -48.502
8 ~ Crashes
0
-1 ~ Roads
Display Source Selection
Figure 7
#
__J
637.33 226.26 Kilometers
5. From here, Crashes can be selected against the High Crash Zone as inputs to further
analysis or Reporting.
Selecting Crashes in a High Crash Zone
Once a High Crash Zone has been created , ArcMap's native tools can be utilized to select
Crashes contained within the High Crash Zone area. To accomplish this:
1. Click 'Selection' -7 'Select by Location' on the ArcMap menu bar.
2. The following Dialog will be displayed.
a. Choose 'select features from ';
b. Select 'Crashes';
c. Select 'are contained by';
d. Select the High Crash Zone (e .g. "CRASH ZONE: SR> 50%")
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FHWA GIS High Crash Zones Tools v4.0
Lets you select features horn one or more layers based on where they are located
in relation to the features in another layer.
I \:Yant to: I select features from
tbe following layer( s ):
0 CRASH ZONE: SR > 50%
~Crashes
D Roads
r 0 nly ~how selectable layers in this list
!hat: I are contained by
the jeatures in this layer: I ..
r l,)>e elr-cted fealure: (0 features selected)
r AQply a buffer to the features in CRASH ZONE: SR > 50%
Qf: lu 000000 I ,r, m , ·~ :::J
Preview -----
The red features represent the features in CRASH ZONE: SR> 50%.
The highlighted cyan features are selected because they
are contained by the red features.
()
0
Points Lines Polygons
8pply .(;lose
Figure 8
Click 'Apply' to generate the selection set of only Crashes contained wi thin the High
Crash Zone.
3. Once the Crashes have been selected, the user has the option to use the selections in
another operation or export the selected Crashes to a new dataset.
4. To Export the selected Crashes, right click the 'Crashes' layer, select 'Data' and 'Export
Data'. A dialog will appear. Make sure 'selected features' is chosen and choose an
output location (either Shapefile or Geodatabase Feature Class).
Use the same coordinate system as:
r. this layer's source data
r the data frame
r the feature dataset )IOU export the data into
[only applies if you export to a feature dataset in a geodatabase)
Output shapefile or feature class:
lc:\VHB\MA Crashes\ Temp\Export_Output shp ~
OK Cancel I
Figure 9
The layer resulting from the Export operation can be used as an input layer for the Report
eng ine.
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FHWA GIS High Crash Zones Tools v4.0
Report
Custom reports can be generated using the Crystal Reports engine bundled with ArcGIS.
1. Select (highlight) the single Layer (not a Group Layer) in the Table of Contents from
which the report is to be generated.
2. Click the 'Report' command on the 'FHWA HCZ Analysis' toolbar 'Tools' menu.
3. A Dialog is displayed allowing the parameters of the Report to be set:
a. Report Template -The Crystal Reports template (.rpt) that defines the layout and
data groupings for the report.
b. Map Template -If a Map is to be included in the Report, this parameter allows the
user to select the Map Template (.mxt)
c. Values -Additional values that can be included within the Report.
•Report Template Setup
Report Template -----,.,._.....,.-...,..,..,_,_ _ ___,.,..,._,
j C: \VH B \Safety\ v4 \Saf ety\R eports\CrashS ummaryB yM
~Map/fmagelayou\ IernpleW
*
Report Title
Print Time
No image required
5/30/2006
Safety.mxd
Safety
3:04 PM
OK Cancel ~ --~ ----;:Jzl
Figure 10
Once all of the parameters are entered, press OK .
4. The Report is then generated and displayed in a new window. From this new window the
report can be viewed , exported to a variety or formats or printed.
Note: When a new report template is selected , the Toolbar checks to see if a Map is included
within the Report. If so, the 'Map Template' edit line is activated.
It is required that the user create the report templates they wish to use. Refer to the
Crystal Reports documentation for more information on how to create reports. To use
this tool , it is required that the report template file (.rpt) conta in the same data schema
definition as the selected layer.
Note: The use of this tool does not preclude the use of the native ArcMap report tools that
utilize Crystal Reports. Please refer to the ArcGIS Desktop Help for more information on
how to use ArcMap's native Reporting tools.
Map Template
Custom maps can be generated using the predefined Map Templates.
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1. Click the 'Map Template' command on the 'FHWA HCZ Analysis' toolbar 'Tools' menu.
2. A Dialog is displayed allowing the parameters of the Map to be set:
a. Printer -The printer on which the Map is to be produced.
b. Map Template -Allows the user to select the Map Template (.mxt)
c. Values -Additional values that can be included within the Map.
~ Ma11 Tem11late Setup
: RICOH Aficio 2035e PS Setup ...
Map Template ....,....._..,... ________ .......,
IC:\ vhb\S af ety\ v4 \S af ety\S afety. mxt
Value
5/30/2006
C:\VHB\Safety\v4\Safet
2:51 PM
Safety.mxd
Analysis 112
OK Cancel I ~-----~
Figure 11
Once all of the parameters are entered, press OK.
3. The Map is then generated and displayed.
ADM Setup
Manages the ADM Database. To access the ADM Setup tool:
1. Click the 'ADM Setup' command on the 'FHWA HCZ Analysis' toolbar 'Tools' menu.
For specific information about using this tool, refer to 'Appendix B -ADM Setup'.
Database Connection
Change the Connection to the active Database.
1. Cl ick the 'Database Connection' command on the 'FHWA HCZ Analysis' toolbar 'Tools'
menu.
2. The 'Database Connection' dialog will be displayed :
Cl Database Connection
lc:\S afety\S alety. mdb
OK Cancel I L--...J ---~
Figure 12
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FHWA GIS High Crash Zones Tools v4.0
3. Either type in the Path and Name of the ADM database (i.e., 'c:\VHB\MyProj\adm .mdb')
or use the Browse button.
4. Once selected , press the 'OK' button .
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FHWA GIS High Crash Zones Tools v4.0
Appendix A -New Project Setup
To provide a high level of configurability, the FHWA High Crash Zone application uses the
ArcGIS Data Manager (ADM) to manage all of the data used within the application. The ADM
consists of a number of related tables stored within a Microsoft Access database. These tables
define all of the Feature Classes, Tables, Layers and related data accessible by the FHWA High
Crash Zone application. For a detailed description of the ADM, refer to the document 'ArcGIS
Data Manager Version 2.0 Data Dictionary'.
Note: It is assumed that the user setting up the new Project ADM database is familiar with
ArcGIS and how to load , join, linear reference and classify data.
Initialization
To initialize the database for a new Project:
1. Create a new Project directory (i.e., 'c:\HCZ').
2. Copy the ADM database 'HCZADM.mdb' and the Map template ('HCZ.mxt') from the
application installation directory (i.e., 'c:\Program Files\FHWA') to the new Project
directory.
3. Open ArcGIS.
4. The FHWA HCZ Analysis toolbar should load automatically. If not, select 'View -7
Toolbars -7 FHWA HCZ Analysis.
5. Save the blank ArcGIS Project into the Project directory (i.e., 'c:\HCZ\HCZ.mxd').
6. Select the 'Tools -7 Database Connection ' menu option on the 'FHWA HCZ Analysis'
toolbar. The 'Database Connection' dialog will be displayed:
~Database Connection
j C: \S af ety\S af ety. mdb
OK Cancel I ._ ............ __ ~
7. Either type in the Path and Name of the ADM database (i.e., 'c:\HCZ\HCZADM.mdb') or
use the Browse button. Once selected , press the 'OK' button .
8. Resave the updated ArcGIS Project into the project directory (i.e.,
'c:\HCZ\HCZADM.mxd').
Data Reference
For the FHWA High Crash Zone application to function successfully, the Crashes Layer needs
to be correctly defined, while other Layers are optional but provide background and reference
data. These Layers are defined within the ADM database and are based upon defined Feature
Classes and Attribute Tables.
Note: For examples on referencing the Feature Classes , Tables and Layers, refer to the ADM
database contained with any of the example datasets.
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FHWA GIS High Crash Zones Tools v4.0
Feature Classes
The FHWA High Crash Zone application requires four Feature Class references to be setup
within the 'ADMFeatureClass' Table in the ADM database.
Tag Feature Class Type Description
Roads
Crashes
Polyline
Points
Featur~ Class used _!9_display the Roads. Only used as reference.
Route System used to display Crashes within the analysis area. Must
contain a unique ID (Primary Key) field that is defined as the 'Key Field'
for this Feature Class.
These references can be entered either manually by opening the ADM database in Microsoft
Access and editing the 'ADMFeatureClass' Table, or using the 'ADM Setup' functionality (see '
Appendix B -ADM Setup', '5 -ADM Feature Class').
Tables
The FHWA High Crash Zones application doesn't require any tables to be configured in the
ADM database. If it is desired that tables be made available through this interface, please refer
to the 'ArcGIS Data Manager Version 2.0 Data Dictionary'
Layers
The FHWA GIS Safety tools application requires eleven Layer references to be setup within the
'ADMLayer' Table in the ADM database.
Tag
Roads
Crashes
HCZ Crash Grid
HCZ Crash Zone
Crashes (Selection )
Feature Class Key Field
Based on
Roads Route ID Field
Crashes Crash ID
Description
Roads Layer (for reference purposes)
Defines the location of all of the Crash to be
analyzed by the application
Predefined. Definition to use when displaying
Crash Grid
Predefined . Definition to use when displaying
High Crash Zones
Predefined. Definition to use when displaying
Crash Selections
These references can be entered either manually by opening the ADM database in Microsoft
Access and editing the 'ADMFeatureClass' Table, or using the 'ADM Setup' functionality (see '
Appendix B -ADM Setup', '7 -ADM Layer').
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FHWA GIS High Crash Zones Tools v4.0
Initialization Parameters
To allow the FHWA High Crash Zones application to 'understand' the data that it is accessing,
several initialization parameters need to be set in the 'ADMSetup' table.
Parameter
Client
Version
HCZ Grid Cell Size (Map
Units)
HCZ Grid Scale Factor (Map
Units)
HCZ Scaled Grid Units
(Display)_
HCZ Grid Units (Display)
HCZ Grid Layer Tag (ADM)
HCZ Output Zone Name
(ADM)
Primary Crash Layer Tag
(ADM)
Output Folder
Crash ID Field Name
Description
Client name
~OM Version (Re_guired}_
The size of the Grid Cells used in the Density
Grid creation. Units are in map units (i.e.
Meter~) (Required)
Scale Factor used to scale results. (i.e.
meters7kilometers) (Required)
The unit name to display for the HCZ Density
Grid (Required)
The units to display for the search radius
(Requir~d)
The name of the Grid Layer Tag in the ADM
(RE:)q~iredL_ . __
The name of the output High Crash Zone
dataset (Required)
The name of the layer ADM layer Tag to use
(Required)
The name and path of the Output location to
store Analysis Shape files (Required). Note:
Note: $PROJ\ indicates the path of the parent
.mxd file.
The name of the unique ID (i.e. Crash_ID)
field in the Crashes layer (Required)
Example Setting
VHB
2.0
20
1000
km
m
HCZ Crash Grid
HCZZone
Crashes
$PROJ\Output
Crash ID
These references can be entered either manually by opening the ADM database in Microsoft
Access and editing the 'ADMSetup' Table, or using the 'ADM Setup' functionality (see 'Appendix
B -ADM Setup', '1 -ADM Setup').
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FHWA GIS High Crash Zones Tools v4.0
Appendix B -ADM Setup
The ADM (ArcView Data Manager) Setup Tool provides a way to manage the ADM database
that contains references about all data used in the project. The database is broken out into eight
Elements:
1. ADM Setup -Initialization parameters.
2. ADM Environment -Environment variables.
3. ADM SOL -SOL database connections.
4. ADM SOE -ArcSDE database connections.
5. ADM Feature Class -Spatial data
6. ADM Table -Attribute data.
7. ADM Layer-Map Layers.
8. ADM Layer Related -Many-to-one data relationships.
All ADM maintenance events are initiated from the main ADM Setup Dialog.
• Add -Adds a new reference to the selected ADM Element.
• Edit -Edit the selected ADM Element reference.
• Delete -Removes the selected ADM Element reference from the ADM database.
Select the ADM Element
1±1 .. il:Mllllliiilii!lil
EfJ 2 ·ADM Environment
1±1 3 -ADM SQL
El 4 ·ADM SDE
Demo
MA Rasters
USA MA
1±1 5 ·ADM Feature Class
1±1 6 ·ADM Table
1±1 7 ·ADM Layer
[±] 8 ·ADM Layer Related
.!.. , I
Add
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FHWA GIS High Crash Zones Tools v4.0
1-ADM Setup
The ADM Setup dialog provides the ability to set a Parameter and its corresponding Setting.
• Parameter -The name of the Parameter.
• Setting -The value that corresponds to the Parameter.
Parameter !output Folder
Setting I $PR OJ \output
OK Cancel
Note: To maintain system stability, the two Parameters 'Client' and 'Version' cannot be edited.
2 -ADM Environment
The ADM Environment dialog provides the ability set a dynamic path Variable and its
corresponding Value.
• Variable -The name of the Variable. Note: It is required that this name begin with a
dollar sign ('$') and contain no spaces.
• Value -The directory path that the Variable corresponds to.
Variable I $L YR
Value j$PROJ\lyr
ll OK JI Cancel I
Note: The '$PROJ' variable can not be edited since it is related to the path of current ArcMap
Project file and is dynamically set.
3-ADMSQL
The ADM SOL dialog provides the ability set the SOL Connection properties.
• Tag -This is used for reference purposes and must be unique.
• Type -The type of SOL Connection .
• DB Path -The path to the MS Access database if Type= 'MS Access'.
• Connection String -The actual ADO Connection String that is used to connect to the
database.
o If Type 'MS Access' is selected , the Connection String is created automatically
and not editable.
o For other Types, the Connection String must be modified to establish the
connection.
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Tag
Type
DB Path
Connection
String
lrnc
jMs Access
I $PR OJ \database\FD C. mdb
P1ov1oer M1cro.olt Jet(..LE[; l 4 0. Oats
So1.1n:·e:1PROJ' :Jat.lb<re\FD-mcfl
Test I I DK ] Cancel
Click 'Test' to test the SQL connection with the current settings.
Click 'OK' to save the SQL connection properties to the ADM database.
4-ADM SDE
The ADM SOE dialog provides the ability to set the SOE Server Connection Properties. All fields
are required.
• Tag -Used for reference purposes. Must be unique.
• Server -The name of the ArcSDE Server to connect to.
• Version -The Version of the database to connect to. In most cases th is will be
'sde.default'
• Instance -The Instance number to use for the connection.
• User - A valid user name that has access to the SOE Server instance.
• Password -A valid password that corresponds to the User name.
Tag Name jMA Raste1s
Se1ve1 jA1cSDE
Ve1sion jsde.default
Instance 15186
Use1 jvhbuse1
Password lvhbuse1
Test I IL DK :.:::J] Cancel
Click 'Test' to test the connection with the current settings and indicates whether the test was
successful.
Click 'OK' to save the connection properties to the ADM database.
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5 -ADM Feature Class
The ADM Feature Class Dialog provides the ability to define all of the Spatial data (Feature
Classes) that can be accessed by the Project.
Note: Depending upon the type of the Feature Class that has been selected , the actual
required and optional data fields will vary.
• Tag -Used for reference purposes. Must be unique.
• Module -The Module with which to associate the ADM Feature Class.
• Data Type -The type of the ArcGIS Workspace that contains the Feature Class.
• Shapefile -(Arclnfo, dBase, File, Raster, SOC & Shapefile Only) Path and Name of the
appropriate file.
• Connection -(SQL Only) Name of the defined ADM SQL Connection.
• SQL Select -(SQL Only) Select portion of the SQL statement that defines which fields
to retrieve.
• SQL From -(SQL Only) The Table or View from which the data is retrieved.
• SQL Where -(SQL Only) (Optional) The Where Clause that defines the filter for the
data.
• SQL Group By -(SQL Only) (Optional) Name(s) of the field(s) by which the data should
be grouped.
• SOE Connection -(SOE Only) Name of the defined ADM SOE Connection.
• SOE Data Source -(SOE Only) Name of the Feature Class available via the selected
SOE Connection.
• X Coord Field -(dBase, File or SQL) The field in the dataset that defines the X
Coordinate.
• Y Coord Field -(dBase, File or SQL) The field in the dataset that defines the Y
Coordinate.
• Coordinate System -(Optional) The Coordinate System of the data.
• Key Field -(Not Raster) (Optional) The name of the unique field to use as the key for
each Feature in the Feature Class.
• Name Field -(Not Raster) (Optional) The name of the field to use as the name for each
Feature in the Feature Class.
• Comments -(Optional) Any additional information to record about the ADM Feature
Class.
• Active -Is the ADM Feature Class active?
• Required -Is this ADM Feature Class required for the Project to function correctly?
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If a file based Feature Class (i.e., Arclnfo, dBase, File, Raster, SOC, Shapefile} is selected , a
Dialog similar to the one below will be displayed.
Tag Name !crashes [Shapefile) Active P"
Module I Basemap :::J Required P"
Data Type I ShapeFile .:.!
Shape File I $PR OJ \B asemap\S hape\Cambridge\R cutes. shp &]
Key Field
Name Field lsrnEET
Comments
Test I ._I __ o_K_"" Cancel
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If an SOL Data Type is selected, the following Dialog will be displayed.
rj fVl
.. __ -;.,'l.:il."''"'-~-"'~:;< .... _..,e,~ .. ,~~··-.~· ---'1:.r:~ .. ~i;,ir:~--~·"i:~ .. l~
Tag Name jSQL Example Active P"
Module lsasemap ..:.I Required r
Data Type lsQL ..:.I
Connection jrnc ..:.I
SQL Select
SQL From I vcG enericPointVertex
SQLWhere jPointlD>5
SQL Group By
X Coard Field jxcoord ..:.I
Y Coard Field jYCoord ..:.I
Coordinate System junknown ..:.I
Key Field IPointlD ..:.I
Name Field IPointlD ..:.I
Comments
Test I I OK Cancel
Note: To retrieve and refresh the available fields for the X and Y Coordinates and Key/Name
Fields, click the 'Test' button.
Click 'Test' to ensure that the Feature Class can be successfully retrieved.
Click 'OK' to save the Feature Class reference to the ADM database.
6-ADM Table
The ADM Table dialog provides an interface for setting up table based data sources.
• Tag -Used for reference purposes. Must be unique.
• Module -The Module with which the ADM Table is associated.
• Data Type -The type of the ArcGIS Workspace that contains the Table.
• Data Type -The type of ADM Table. The following Types exist:
o Attribute - A simple standalone table.
o Join -The table is joined to a define ADM Feature Class.
o Point Event - A table containing Point Events, linearly referenced against a
Route System.
o Linear Event - A table containing Linear Events, linearly referenced against a
Route System.
• Connection -(SOL Only) Name of the defined ADM SOL Connection.
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FHWA GIS High Crash Zones Tools v4.0
• SQL Select -(SQL Only) Select portion of the SQL statement that defines the fields to
retrieve.
• SQL From -(SQL Only) The Table or View from which the data is retrieved.
• SQL Where -(SQL Only) (Optional) The Where Clause that defines the filter for the
data.
• SQL Group By -(SQL Only) (Optional) Name(s) of the field(s) by which the data should
be grouped.
• Key Field -(Optional) The name of the field to use as the key for each Table record.
• Name Field -(Optional) The name of the field to use as the name for each Table record.
• Comments -(Optional) Any additional information to record about the ADM Table.
• Active -Is the ADM Table active?
• Required -Is this ADM Table required for the Project to function correctly?
Tag Name jGeneric Point Active P'
Module !Generic ..:J Required r
Data Type JsaL ..:J
Type !Join ..:J
Connection lrnc ..:J
SQL Select
SQL From lvcGenericPoint
SQLWhere
SQL Group By
Key Field ..:J
Name Field I <none> ..:J
Comments
Feature Class I Generic Point
Feature Class Field I FD Cl D
Table Field I PointlD
Test I I OK Cancel
Note: To retrieve and refresh the available fields for the X and Y Coordinates and Key/Name
Fields, click the 'Test' button .
Click 'Test' to ensure that the Table can be successfully retrieved.
Click 'OK' to save the Table reference to the ADM database.
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FHWA GIS High Crash Zones Tools v4.0
7-ADM Layer
The ADM Layer Dialog provides the ability to define all of the Layers that will be accessible by
the Project.
• Tag -Used for reference purposes. Must be unique.
• Module -The Module with which associate the ADM Layer.
• ADM Feature Class -The ADM Feature Class upon which the Layer is based.
• Folder Name -The name of the folder (grouping) for the Layer when displayed in the
'Display Layer' Dialog.
• Name -The name of the Layer.
• Key Field -(Optional) The name of the field to use as the unique key for each Feature.
• Name Field -(Optional) The name of the field to use as the name for each Feature.
• Layer File -(Optional) Path and Name of the ArcMap Layer file (.lyr) used to classify the
Features.
• Comments -(Optional) -Any additional information to record about the ADM Layer.
• Real -Does the ADM Layer reference refer to an existing Feature Class?
• Visible -Is the Layer visible on the Map when the Layer is displayed?
• Legend Visible -Is the Layer Legend visible in the Table of Contents when it is
displayed?
• Startup TOC -Is the Layer Legend visible/active?
Tag Name I Generic Point Real P'
Module !Generic ..:J Visible P'
ADM Feature Class j Generic Point ..:J
Legend Visible r
Startup TDC P'
Folder Name !Generic
Name Point
Key Field IPointlD ..:J
Name Field jName ..:J
Layer File I $PR OJ \G eneric\G enericPoint. lyr gJ
Comments This is a generic point layer
Test I I OK Cancel
Click 'Test' to ensure that the data source can be successfully retrieved and that the Layer can
be successfully formed and rendered in ArcMap.
Click 'OK' to save a reference to the ADM Layer to the ADM database.
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FHWA GIS High Crash Zones Tools v4.0
8 -ADM Layer Related
ADM Layers can be related to any ADM Table by using this interface. Simply select the ADM
Layer and the Table to join to and the fields to join. The relationship can be further extended by
adding a Lookup table which can be joined to the parent Layer Related relationship.
• Layer -The ADM Layer.
• Layer Relate Field -The Field Name in the Layer that is used for the join,
• Table -The ADM Table to join.
• Table Relate Field -The name of the field in the Table that is used in the join.
• Lookup Table -(Optional) Name of the table that is used as a Lookup, if any,
• Lookup Layer Field -(Optional) The Field Name in the Layer Related that is used for the
join.
• Lookup Table Field -(Optional} The name of the field in the Lookup Table that is used in
the join.
Layer I Vegetation Polygon ..:.!
Layer Relate Field IPolygonlD ..:.!
Table I vegetation Polygon Related ..:.!
Table Relate Field IPolygonlD 3
Optiono/
Lookup Table !vegetation Polygon Species ..:.!
Lookup Layer Field IPolygonlD ..:.!
Lookup Table Field IPolygonlD 3
Test OK Cancel I
Click 'Test' to ensure that both data sources can be successfully retrieved and that they can be
joined using the selected fields.
Click 'OK' to save a reference to the ADM Layer Related record to the ADM database.
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