Data Collection and AADT Estimation on Non-Federal Aid System 

Roads

DELAWARE VALLEY REGIONAL PLANNING COMMISSION’S

INNOVATIVE TRAFFIC DATA SHARING PRACTICES

CASE STUDY

FHWA-SA-17-033

Federal Highway Administration Office of Safety 

Roadway Safety Data Program 

http://safety.fhwa.dot.gov/rsdp/

February 10, 2017
DVRPC CASE STUDY 

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Notice 

This document is disseminated under the sponsorship of the U.S. Department of 

Transportation in the interest of information exchange. The U.S. Government assumes no 

liability for the use of the information contained in this document. 

The U.S. Government does not endorse products or manufacturers. Trademarks or 

manufacturers’ names appear in this report only because they are considered essential to the 

objective of the document. 

Quality Assurance Statement 

The Federal Highway Administration (FHWA) provides high-quality information to serve 

Government, industry, and the public in a manner that promotes public understanding. 

Standards and policies are used to ensure and maximize the quality, objectivity, utility, and 

integrity of its information. FHWA periodically reviews quality issues and adjusts its programs 

and processes to ensure continuous quality improvement. 
DVRPC CASE STUDY 

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TECHNICAL DOCUMENTATION PAGE 

1. Report No.

FHWA-SA-17-033

2. Government Accession 

No.

3. Recipient's Catalog No.

4. Title and Subtitle

Delaware Valley Regional Planning Commission’s Innovative Traffic Data 

Sharing Practices 

5. Report Date

February 2017

6. Performing Organization Code

7. Author(s) 

Ioannis Tsapakis, William Holik, Anita Vandervalk, Shawn Turner, and John 

Habermann

8. Performing Organization Report No.

9. Performing Organization Name and Address

Texas A&M Transportation Institute (TTI)

Texas A&M University System 

3135 TAMU

College Station, TX 77843-3135

10. Work Unit No.

11. Contract or Grant No.

DTFH6116D00004

12. Sponsoring Agency Name and Address

Federal Highway Administration Office of Safety 

1200 New Jersey Ave., SE

Washington, DC 20590

13. Type of Report and Period

Case Study, August 2016–February 

2018 

14. Sponsoring Agency Code

FHWA

15. Supplementary Notes

The contract manager for this report was Stuart Thompson, Office of Safety. 

16. Abstract

This case study highlights how the Delaware Valley Regional Planning Commission (DVRPC) promotes traffic data 

sharing with other agencies and makes traffic and geographic information system data available to the public. DVRPC has 

developed an interactive mapping application, called Traffic Count Viewer, that provides open access to different types of 

short-duration traffic counts that DVRPC and other external entities take. Traffic Count Viewer communicates with a 

regional database that DVRPC maintains, allowing users to view, filter, and download traffic data. Further, users can 

directly connect to DVRPC’s ArcGIS server map service and extract data for traffic and safety analysis. After 

implementing this tool, DVRPC minimized duplicate data collection efforts, increased the efficiency of its data collection 

program, and improved its relationships with external entities by offering no-cost access to a comprehensive data source. 

The Viewer also resulted in time and cost savings for DVRPC’s data partners and provided quick and easy access to data 

that otherwise would be difficult to obtain. DVRPC will continue to improve Traffic Count Viewer, considering its 

increased popularity with and positive feedback from users.

17. Key Words: 

traffic counts, AADT, data collection, data 

sharing, data viewer

18. Distribution Statement

No restrictions.

19. Security Classif. (of this report)

Unclassified

20. Security Classif. (of this 

page) Unclassified

21. No. of Pages

 28

22. Price

Form DOT F 1700.7 (8-72) Reproduction of Completed Pages authorized
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ACRONYMS 

Table 1. Acronyms. 

Acronym Description

AADT Annual Average Daily Traffic

API Application Program Interface

DOT Department of Transportation

DVRPC Delaware Valley Regional Planning Commission

GIS Geographic Information System

LRS Linear Referencing System

MPO Metropolitan Planning Organization

QA/QC Quality Assurance/Quality Control

REST Representational State Transfer

TIP Transportation Improvement Program
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EXECUTIVE SUMMARY 

This case study presents how a metropolitan planning organization, the Delaware Valley 

Regional Planning Commission (DVRPC), promotes traffic data sharing with other agencies and 

makes traffic and geographic information system (GIS) data available to the public. DVRPC has 

developed an open-source-code web platform, called Traffic Count Viewer, which provides 

public access to different types of short-duration traffic counts that DVRPC and other external 

entities take. Traffic Count Viewer communicates with a regional database that DVRPC 

maintains, allowing users to view, filter, and download traffic data. Further, users can directly 

connect to DVRPC’s ArcGIS server and extract GIS layers and data in a tabular format for 

traffic, safety, and other types of analyses. After implementing this tool, DVRPC minimized data 

collection duplication, increased data collection program efficiency, and improved relationships 

with external entities by offering no-cost access to a comprehensive data source. Additional 

benefits of the Viewer were time and cost savings for DVRPC’s data partners, as well as quick 

and easy access to data that otherwise would be difficult to obtain. DVRPC will continue to 

improve Traffic Count Viewer, considering its increased popularity and positive feedback from 

users. 
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TABLE OF CONTENTS 

INTRODUCTION ....................................................................................... 7

BACKGROUND .......................................................................................... 9

TRAFFIC COUNT DATA SHARING TOOL .........................................10

DEVELOPMENT AND IMPLEMENTATION ........................................................10

PARTICIPATING AGENCIES.................................................................................10

QUALITY ASSURANCE/QUALITY CONTROL (QA/QC) ................................. 11

FUNCTIONALITY ....................................................................................................11

ARCGIS SERVER MAP SERVICE ............................................................................18

OTHER TRAFFIC DATA TYPES ............................................................................20

APPLICABILITY TO OTHER AGENCIES .............................................24

REFERENCES ............................................................................................26
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LIST OF TABLES 

Table 1. Acronyms. ........................................................................................................... 3

LIST OF FIGURES 

Figure 1. DVRPC’s Interactive Mapping Applications................................................... 7

Figure 2. Search Options in Traffic Count Viewer. .....................................................12

Figure 3. Main Webpage of Traffic Count Viewer. ......................................................13

Figure 4. Available Types of Traffic Counts.................................................................. 14

Figure 5. Count Type Selection. ....................................................................................14

Figure 6. Year Selection. ................................................................................................. 14

Figure 7. Example of PDF File (Traffic Volume Count). .............................................16

Figure 8. Example of PDF File (Turning Movement Count). .....................................17

Figure 9. Search Counts by DVRPC File Number. ......................................................18

Figure 10. ArcGIS Server Map Services. .......................................................................19

Figure 11. Feature Layers and Tables. ..........................................................................20

Figure 12. Permanent Bicycle and Pedestrian Counters. ...........................................21

Figure 13. Short-Duration Pedestrian and Bicycle Counts. ........................................22

Figure 14. Permanent Bicycle and Pedestrian Station Data. .....................................23
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INTRODUCTION 

The purpose of this case study is to highlight how a metropolitan planning organization (MPO), 

the Delaware Valley Regional Planning Commission (DVRPC), promotes traffic data sharing 

with the public and other state, county, and local governments. DVRPC has developed several 

interactive mapping applications (Figure 1) to support planning and improve decision-making in 

the Greater Philadelphia Region. Within each application, users can view geographic features, 

query selective data sets, create custom maps, and access detailed reports about certain 

features. These web mapping applications allow DVRPC to present geospatial information to 

the public without requiring special geographic information system (GIS) software. 

Figure 1. DVRPC’s Interactive Mapping Applications.

Source: http://www.dvrpc.org/Mapping/Webmaps/ 
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This case study focuses on one of these applications, called Traffic Count Viewer, which 

provides open access to different types of short-duration traffic counts. DVRPC gathers traffic 

data, collected both in-house and by external entities. After cleaning and processing the data, it 

stores them in a regional database. Traffic Count Viewer communicates with the database, 

allowing users to view, filter, and download the count data. Further, users can directly connect 

to DVRPC’s ArcGIS server and extract GIS layers and data in a tabular format for traffic, safety, 

and other types of analyses. This practice has benefited DVRPC and stakeholders such as 

transportation engineers, planners, developers, market analysts, and the public. The main 

benefits involve: 

 Increased efficiency of the data collection program by creating and maintaining a central 

data depository. Users do not have to extract and process data from multiple remote 

data sources, 

 Elimination of duplicate data collection efforts, resulting in time and cost savings for data 

partners and users, 

 Quick and easy access to data regardless of users’ objectives, background, and 

knowledge level in database administration and data management, 

 Improved relationships with external entities by offering no-cost access to a 

comprehensive data source, and 

 Improved data transparency by allowing users open access to DVRPC’s ArcGIS server 

to: download different types of traffic counts, GIS layers, and other metadata for 

analytical purposes. 

Because of the positive experience and feedback related to this initiative, DVRPC will continue 

to improve Traffic Count Viewer and collaborate with more stakeholders.
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BACKGROUND 

DVRPC is the federally designated MPO for the Greater Philadelphia Region and serves nine 

counties in two states: Bucks, Chester, Delaware, Montgomery, and Philadelphia in 

Pennsylvania; and Burlington, Camden, Gloucester, and Mercer in New Jersey. DVRPC 

cooperates with other state, county, and local agencies to support various transportation 

planning and programming functions. Two of the most important objectives of DVRPC include 

the development of a long-range plan and the Transportation Improvement Program (TIP). 

Toward these objectives, DVRPC collects different types of travel data through surveys, counts, 

and innovative web applications and uses them as input in various analytical tools. 

DVRPC conducts short-duration traffic counts every year at over 5,000 locations using 

pneumatic road tubes. Rural minor collectors and local roads account for approximately 

20 percent of these counts. DVRPC also obtains traffic and non-traffic data collected by other 

entities and stores internal and external traffic data in a database that it developed and 

maintains. DVRPC publishes the data online and allows users to explore them using modern 

GIS mapping applications, data reporting, and other visualization tools. It provides open access 

to the data as a public map service, allowing users to connect to its ArcGIS server using a URL 

link. From there, users can download GIS layers, metadata, and various traffic data in a tabular 

format that is suitable for analytical purposes. DVRPC also provides disaggregated data, stored 

in its database, by request. 

The next section presents the most important development and implementation activities, as 

well as basic components and features of Traffic Count Viewer. 
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TRAFFIC COUNT DATA SHARING TOOL 

DEVELOPMENT AND IMPLEMENTATION 

In 2009, DVRPC developed the first version of Traffic Count Viewer to display various traffic 

count data. The main objective of this initiative was to gather, use, and publish data collected 

from various internal and external sources. The goal was to reduce data collection costs, 

promote data sharing, and enhance collaboration with other entities. DVRPC developed the 

first version of the Viewer using a third-party software. DVRPC staff maintained the website for 

approximately seven years. 

In 2016, DVRPC developed (in-house) a second, updated version of Traffic Count Viewer to 

expand its functionality and make it more efficient and user friendly. When developing the new 

application, DVRPC used open-source code technologies and data libraries for several reasons, 

including the following: 

 They allow the creation of modern mapping features and tools that are necessary for a 

web application like Traffic Count Viewer. 

 They work efficiently across most major desktop and mobile platforms. 

 Adding online plugins can extend their functionality. 

 They have well-documented application program interface (API) and free tutorials 

online. 

 They allow individuals to expand the functionality by modifying the open source code. 

 They offer several open-source code blogs and forums that address users’ questions and 

issues, and provide relevant information and technical support. 

 They may be transferrable to other agencies. 

DVRPC shares the open-source code, by request, to help agencies develop and implement 

similar products. 

PARTICIPATING AGENCIES

The Traffic Count Viewer displays traffic data collected by DVRPC and other entities. External 

entities such as HERE (formerly traffic.com) collected approximately 30 percent of the data that 

are available on DVRPC’s website. Consultants conduct a high percent of short-term counts 

that they use in special studies, and they occasionally send the traffic data to DVRPC. They 
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must also directly submit the traffic data they collect to DVRPC. This requirement accelerates 

the data sharing process and enhances data collaboration among agencies. DVRPC downloads 

counts from the New Jersey Department of Transportation’s (DOT’s) website and uploads 

them to its database. The counts that DVRPC takes for the Pennsylvania DOT are also available 

on the Traffic Count Viewer. 

Collecting and storing traffic data in a central depository and making the regional database 

accessible online benefits DVRPC and other stakeholders, who traditionally use traffic data to 

address certain needs and make decisions. For clarity, DVRPC publishes one PDF file for each 

traffic count available on Traffic Count Viewer indicating the count taker and the data source 

(internal or external). Users also have the option to connect to DVRPC’s ArcGIS server and 

download in an electronic tabular format various data for traffic and safety analyses. DVRPC 

also provides, by request, disaggregated data that are stored in its database but not available in 

the Viewer. 

QUALITY ASSURANCE/QUALITY CONTROL (QA/QC) 

DVRPC conducts QA/QC checks to ensure quality of the data before publishing them online. 

For the counts conducted internally, DVRPC staff compares the traffic patterns of a new count 

against those of historical counts from the same location or from adjacent counted segments if 

historical data at the location of interest are not available. DVRPC staff determines counts that 

deviate from historical traffic patterns by 20 percent or more and identifies possible causes of 

the variations. DVRPC documents these causes by commenting in the PDF files. Depending on 

the validity of a potential cause, DVRPC repeats counts that do not pass the quality checks. 

DVRPC follows the same QA/QC process for the counts received from other agencies. If the 

counts do not pass the quality control checks and there is no evident cause of the potential 

discrepancies in the data, DVRPC does not upload the counts to its database. Instead, it 

contacts the data provider and asks for additional information (for example, construction, 

inclement weather conditions) that may explain the data variations. Occasionally, some data 

suppliers retake counts to address the issues. 

FUNCTIONALITY 

Traffic Count Viewer provides users with multiple options, such as: 

 Search counts by area. 

 View locations of counts on a map. 

 Filter counts for specific years. 
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 Download traffic data. 

Figure 2 shows the Viewer webpage that allows users to search for traffic counts within a 

particular zip code or location, which can be a municipality, city, or neighborhood. 

Figure 2. Search Options in Traffic Count Viewer. 

Source: http://www.dvrpc.org/webmaps/TrafficCounts/ 

The webpage also offers two advanced search options: search counts by area and search counts 

by DVRPC file number. The following subsections describe these options, along with other 

functions of the Viewer. 

Search Counts by Area 

When users select this option, the Viewer loads its main webpage (Figure 3), which includes 

two basic components: an interactive map and a traffic-count record report. Users can draw 

the area of interest on the map using custom shapes (lines). They can also pan, zoom in/out, 

and change the background view (for example, from street map to satellite view). Once the 
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user defines the search area, the system extracts from the database all the counts that fall 

within the selected region and displays them on the map (left part of Figure 3). The report next 

to the map (right part of Figure 3) lists the records associated with the selected counts. 

Figure 3. Main Webpage of Traffic Count Viewer. 

Source: http://www.dvrpc.org/webmaps/TrafficCounts/ 

The system displays the counts as color-coded dots based on count type. DVRPC’s database 

contains nine different types of counts, as Figure 4 illustrates. 
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Figure 4. Available Types of Traffic Counts. 

Source: http://www.dvrpc.org/webmaps/TrafficCounts/ 

By clicking on the legend located at the bottom 

left of the map, users can see the available types 

of counts within the selected area. When users 

hover the mouse pointer over a count, a label 

shows the name of the road. When users click 

on a count, the database records are highlighted 

and placed at the top of the report. The Viewer 

also offers two filters for selecting specific types 

of counts (Figure 5) and years of interest (Figure 

6).

The report shows basic information for each 

count including its date, road name, count 

type, annual average daily traffic (AADT) 

value, and DVRPC file number (Figure 3). 

Source: http://www.dvrpc.org/webmaps/TrafficCounts/

Figure 5. Count Type Selection.

Figure 6. Year Selection.

Source: http://www.dvrpc.org/webmaps/TrafficCounts/
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Users can sort the retrieved records by any of these attributes. Further, by checking the boxes 

in the first column of the report, users can select one or multiple records and download their 

PDF files, as well as create a zoomed-in view of these records on the map. 

Figure 7 shows a sample PDF file that contains data from a traffic volume count. The file 

includes traffic data aggregated at hourly intervals and shows additional information (for 

example, weather, speed limit, functional class, station ID, county, travel direction, seasonal 

adjustment factor, and axle adjustment factor) that may be of interest to users. Figure 8 shows 

the first page of a PDF file that contains turning movement data from a count taken at the 

intersection of NJ 47 and Cooper Street in New Jersey. 
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Figure 7. Example of PDF File (Traffic Volume Count). 

Source: http://www.dvrpc.org/webmaps/TrafficCounts/ 
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Figure 8. Example of PDF File (Turning Movement Count). 

Source: http://www.dvrpc.org/webmaps/TrafficCounts/
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Search Counts by DVRPC File Number 

DVRPC assigns a unique number to each PDF file. Users can enter one or multiple DVRPC file 

numbers in the window shown in Figure 9. After users type the file number(s) of interest, the 

main page of the Viewer shows the selected counts. 

Figure 9. Search Counts by DVRPC File Number. 

Source: http://www.dvrpc.org/webmaps/TrafficCounts/ 

ARCGIS SERVER MAP SERVICE 

As the bottom right of Figure 2 illustrates, DVRPC offers open access to its ArcGIS server as a 

map service. When a user selects this option, a new window (Figure 10) appears that includes 

two URL links. 

The first link provides access to DVRPC’s ArcGIS server (an ESRI product) map services that 

include several transportation and non-transportation feature layers and tables (see Figure 11). 

The server provides these features in different formats that are compatible with various GIS 

platforms. One of the tables contains all short-duration counts. Depending on the count type, 

the map service provides some data in an aggregate form. However, DVRPC stores and 

maintains disaggregated data in its database and offers them to interested parties by request. 
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The second link provides access to the Representational State Transfer (REST) API of DVRPC’s 

traffic counts. DVRPC provides the API mainly for developers and advanced users who are 

interested in more detailed technical information (for example, metadata) of each feature. 

Figure 10. ArcGIS Server Map Services. 

Source: http://www.dvrpc.org/webmaps/TrafficCounts/ 

DVRPC uses two geographic reference systems to map each count on the transportation 

network. The first includes the geographic coordinates (latitude and longitude) of each count. 

The second reference system depends on whether a count is located on Pennsylvania or 

New Jersey’s roadway network. For the Pennsylvania counts, DVRPC measures the offset from 

the beginning of a state route segment—for example, PA State Route 21, Segment 100, offset 

1250 ft. For the New Jersey counts, DVRPC uses a state route identifier and a milepoint 

measured from the beginning of the route—for example, NJ State Route 21, milepoint 23.68 

miles. Most local roads are included in the states’ linear referencing system (LRS). 
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Figure 11. Feature Layers and Tables. 

Source: http://www.dvrpc.org/webmaps/TrafficCounts/ 

OTHER TRAFFIC DATA TYPES 

In addition to Traffic Count Viewer, DVRPC has developed other web applications that show 

the following types of count data: 

 Permanent pedestrian and bicycle counters. An interactive map (Figure 12) displays data 

from permanent bicycle and pedestrian counters that DVRPC operates. Trail use 

counters, located on circuit trails throughout the region, record use by direction and 

mode (walking versus bicycling) continuously throughout the year. This map provides a 
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snapshot of the data in a simple, user-friendly format, allowing users to explore counts 

from throughout the region. 

Figure 12. Permanent Bicycle and Pedestrian Counters. 

Source: http://www.dvrpc.org/webmaps/PermBikePed/ 

 Short-duration pedestrian and bicycle counts. An interactive map (Figure 13) displays 

short-duration pedestrian and bicycle count data within and surrounding the DVRPC 

region. Users can review detailed hourly reports, location information, and daily 

estimates of pedestrian and bicycle traffic at select locations. DVRPC provides the data 

as a public service. 
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Figure 13. Short-Duration Pedestrian and Bicycle Counts. 

Source: http://www.dvrpc.org/webmaps/PermBikePed/ 

 Permanent bicycle and pedestrian station data. A PDF report (Figure 14) shows total 

annual volumes of pedestrian and bicycle traffic on the most used trails, where 

permanent counters exist. 
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Figure 14. Permanent Bicycle and Pedestrian Station Data. 

Source: http://www.dvrpc.org/webmaps/PermBikePed/ 
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APPLICABILITY TO OTHER AGENCIES 

DVRPC is innovative, creative, and proactive when it comes to implementing new strategies. 

This practice is part of DVRPC’s culture and accompanies its strategy of coordinating with 

business areas and information technology to incorporate user needs and ideas when 

developing data and information systems. DVRPC’s ideas, strategies, and lessons learned from 

its data collection program and its use of various web-based tools, including Traffic Count 

Viewer, can benefit other stakeholders. Lessons learned regarding traffic data collection, data 

sharing, and web development include the following: 

 Consider ways to collect data once with elements that meet the evolving needs of 

different users. 

 Try to gather traffic data from various sources and create a central data repository 

while making sure the data meet the needs of as many users and agency functions as 

possible. 

 Consider using open-source code and data libraries to develop tools that can have 

multiple end-users within and outside the organization. 

 Try to have people with a background in GIS and database administration, which can 

benefit tool development and implementation. 

 Inform managers and executives on cost savings and other benefits achieved through 

more-efficient processes. 

 Foster people’s willingness to change existing systems and business practices, learn how 

to use new technologies, and adapt to new, fast-evolving environments. 

 Seek to have the right people in the room, which helps with decision-making. 

 Involve all data users from various business areas and consider the needs and 

preferences of different agency functions. This helps secure broad buy-in and support. 

 Relate the costs for data collection and management to the hidden cost of not having 

data or a data warehouse. 

DVRPC plans to continue improving Traffic Count Viewer, considering its increased popularity 

with and positive feedback from users. One of the improvements will be to expand functionality 

to allow New Jersey DOT, Pennsylvania DOT, and local governments to request new count 

data through the Viewer and track the status of each request. Users will be able to select the 

location of a new count on a map and indicate the desired type of count (for example, total 

volume or classification count). The Viewer will provide users with the estimated cost of each 

count by considering the time, resources, and equipment needed. It will also allow users to save 

and edit project requests by adding and removing counts, as well as to track the status of each 
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count (in other words, pending, processing, or completed) over time. Once DVRPC staff 

accepts a request, the system will notify field personnel to take a count at the location 

requested. 

In addition, DVRPC staff is considering adding new advanced search options such as searching 

traffic counts by address and intersection. The staff is also examining the need to allow users to 

upload counts directly through the Viewer. Other agencies can benefit from DVRPC’s example 

of gathering and archiving data from various sources and developing open-source code 

applications and modern visualization tools to promote data sharing, reduce data collection 

costs, improve data collection efficiency, and improve collaboration with other agencies. 
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REFERENCES 

Phone interviews with: 

 Brady, Scott, (Manager, Office of Travel Monitoring, DVRPC), in discussion with the 

author. October 17, 2016. 

 Michael Ruane, (Sr. Transportation Planner, Office of Travel Monitoring, Office of 

Freight and Aviation Planning, DVRPC), in discussion with the author. October 17, 2016. 

Delaware Valley Regional Planning Commission. (2016). “Data” (website). Available online: 

http://www.dvrpc.org/, last accessed December 15, 2016. 

Federal Highway Administration (2016). Traffic Monitoring Guide, Office of Highway Policy 

Information, Washington, D.C. 

HERE (2016) website: https://here.com/en, last accessed December 15, 2016. 

Pennsylvania Department of Transportation. (2015). Pennsylvania Traffic Data, PUB 601 (8-16), 

Bureau of Planning and Research Transportation Planning Division, Harrisburg, PA. 

Ioannis Tsapakis, William Holik, Subasish Das, Shawn Turner, John Habermann, and Edgar 

Kraus from the Texas A&M Transportation Institute and Anita Vandervalk and Herb Weinblatt 

from Cambridge Systematics, Inc. performed this project. 

FHWA, Office of Safety 

Stuart Thompson, P.E. 

Federal Highway Administration 

202-366-8090 

Stuart.Thompson@dot.gov