Transportation Management Center Video Recording and Archiving Best General Practices
Chapter 2. Successful Practices for Recording and Using Video
Closed-circuit television (CCTV) cameras are an important tool in the transportation management toolbox. Transportation agencies rely on them for incident verification, response preparation, traffic management awareness, special events, weather conditions, and much more.
The operational benefits of real-time video are somewhat obvious—so why would an agency also be interested in recording or archiving any of this CCTV video footage?
Once an agency has wrestled with the question of WHY they should record, it next comes down to whether or not they WILL record. This chapter draws upon the opportunities (purposes of recorded video) and constraints (records retention, costs, technology, liability, and privacy) to discuss how agencies make the major decision. This chapter describes the major policy decision in terms of three simplified terms for possible policy options: ALWAYS, SOMETIMES, and NEVER.
Chapter 2 is the first in a series of chapters that provide more detail on groups of issues within the major policy choices of when to record video. The information is meant both to improve the practices of agencies committed to certain policy choices and to provide background to agencies that may be reconsidering their current policy choices. This chapter is also the first to give insight into the relative prevalence of various policies and practices by presenting graphics of results from the online inquiry sent to Transportation Management Center (TMC) staff from around the country.
Uses and Benefits of Recorded Video by Roadway Agencies
Recording and archiving traffic video offers a number of benefits to agencies. As shown in figure 1, TMCs are interested in having recorded video for a variety of purposes with training being the most common.
Some of the types of data collected included bicycle counts, pedestrian counts/flows, vehicle counts for signal timing, observation of merging zones, and observation of a roundabout to be used addressing crash issues.
The "other" category included a variety of responses including allowing media to record brief clips for reporting, capturing transition of reversible lanes, and after-action reviews (which one could argue may be defined the same as training or incidents in the eyes of some respondents). New Jersey’s Statewide Traffic Management Center (STMC) noted that it is using temporary cameras in work zones to record intermittent screen shots to create time-lapse films of construction progress and to be able to verify actual timing of lane closures.
Figure 1: Chart. Purposes of selective video recordings.
(Source: Parsons Brinckerhoff)
The Wisconsin Department of Transportation (WisDOT), which records most feeds most of the time, summarized the benefits of recording video in their 2013 webinar “CCTV Role in WisDOT’s TIM [Traffic Incident Management] Success”:
- The Department of Transportation (DOT) and emergency responders reviewed incidents for lessons learned, best practices, incident debriefs, and emergency traffic control and scene management guidelines.
- Traffic Incident Management (TIM) education and training.
- Improved TIM increases safety and provides economic benefits (travel-time savings).
- Unintentional benefits to law enforcement, both for recording crimes and for enabling investigators to place vehicles or suspects at a specific time and location.
Agencies agreed that the primary purpose of traffic camera video, whether recorded or not, was for traffic management. Additional benefits may exist, such as recordings for evidence of crimes, but TMCs should be clear that their systems were not designed for or intended to be security systems.
Many of the benefits of recorded/archived video are still relatively new to agencies that have only recently upgraded some of their technology and operating systems. Improved digital video recorders and storage units have opened the door to a number of new opportunities and the realization of benefits may be new. A more detailed discussion on technology improvements is featured in chapter 5.
Fundamental Recording Policy Question—Always, Sometimes, or Never
For the purposes of this report it was important to develop general categories to organize the major recording issues. Three groupings of possible policy options are presented as simplified one-word terms: Always, Sometimes, and Never.
Best General Practice
Be clear that the primary purpose of traffic video is for traffic management, not security, noting that the traffic systems were not designed or intended to meet security system requirements.
- ALWAYS—A generalized short-hand for the policy of automatically recording all feeds continuously. Agencies in this category report that in reality this becomes most of the feeds most of the time, recognizing that it is not feasible to record every feed 100 percent of the time due to equipment failures, system maintenance, and special exceptions. This category refers to automatic recording by default. While many feeds are continually recorded, they may only be retained for a few days unless an action is taken by a staff member to save a particular clip longer.
- SOMETIMES—A generalized short-hand for the policy to only record select feeds for specific purposes. By default, feeds are not recorded. An action must be taken by an operator to initiate recording, typically for a limited amount of time to capture an event or period of data collection. This category refers to selective recording or recording only under limited circumstances.
- NEVER—A generalized short-hand for the policy of not recording full-motion video at all, though in practice there may be static image capture or very rare occasions where some clips are retained.
Note that in this chapter the term "record" refers to any retention of video regardless of duration. It is important to note, however, that some agencies differentiate between “record” and “archive” as follows:
- Record—denotes video retained only until it is automatically overwritten.
- Archive—when video clips have been selected for retention beyond the automatic overwriting.
Figure 2 shows that amongst the agencies contacted, only a few chose not to record video—the NEVER category. At the opposite end of the spectrum, only a few agencies recorded most of the time—the ALWAYS category. The most common general practice is to record under limited circumstances for specific purposes—the SOMETIMES category.
Figure 2: Chart. Recording incoming transportation video feeds.
(Source: Parsons Brinckerhoff)
While many agencies have recorded under limited circumstances for many years using simple equipment such as a videocassette recorder (VCR), the introduction of networked digital video recorders and inexpensive storage space have reduced the technical barriers to extensive recording. For agencies that see value in additional recording and have applicable operational and legal/policy frameworks, recording most feeds most of the time has become a possibility. For that reason, there is the opportunity that agencies could revisit their decisions periodically and more could shift to the ALWAYS category over time while others could move from NEVER to SOMETIMES.
Transportation Management Centers that Always Record
For those TMCs that are operating under a policy of recording most or all of the video feeds (ALWAYS), the following observations are relevant.
Capability Maturity (Transportation Management Centers that Always Record)
Best General Practice
A great opportunity to review your policy is presented when opening a new TMC, rehabilitating an existing TMC, or preparing for a series of upcoming events.
Capability maturity models (CMM) provide a framework for agencies to consider for benchmarking and improving their processes. While there are agency-specific legal, policy, and operational factors that preclude such generalized models from being applicable to all situations, the maturity levels below do draw from the experience of successful TMCs.
Traditional capability maturity models have five levels, but to fit this application, they are grouped into three—Initial, Repeatable/Defined, and Managed/Optimizing. The descriptions of each level focus on process and documentation that are generally applicable to TMCs that sometimes record video. Specific tactics within processes, such as a sample file naming convention, are included in subsequent chapters, frequently in the Best General Practices call-out boxes.
Since issues of releasing video clips are similar for TMCs that sometimes record and TMCs that always record except for scale, guidance for release is provided in chapter 3 instead of in this chapter.
Increasing capability maturity is intended to both enhance the transportation management effectiveness of TMCs and to streamline their recording practices. See table 2 for the capability maturity model related to TMCs that record continuously.
Table 2: Capability maturity model for Transportation Management Centers that record most feeds continuously (ALWAYS), focusing on processes to retain specific clips beyond the automatic rewriting time.
|Ad hoc decisions on what to archive, who archives, where files are archived, how files are labeled, and how long they are kept.
||Have written policy with how requests to save are made, who processes requests, how saved files are organized and labeled, how the process is documented, and how long files are kept.
||Document annual uses of recordings and saved clips including value added and necessary staff time and technical resources to provide; consider needs to revise policies and practices, including reaching out to stakeholders to see if select recordings would support related functions such as engineering studies; consider process simplification.
Additional detail of strategies to support efficient release of recorded video are found in chapter 3.
Length of Time Recordings are Kept for Transportation Management Centers that Always Record
The agencies that always record do so by recording onto media in a continuous loop until it is automatically overwritten after a minimum amount of time. The minimum length of time drives how much storage space is necessary. Agencies recorded a variety of minimum retention times:
- Minnesota: four days.
- Iowa: three days.
- Wisconsin: three days.
- New Jersey: seven days.
Per the Minnesota Department of Transportation’s (MnDOT) "Traffic Camera Imagery Recording and Distribution" policy dated December 4th, 2012, retention times vary on the use. The complete listing is as follows:
- Imagery automatically captured and temporarily stored by the system—two to four days.
- Imagery archived by an operator at the request of a government agency for investigation—one year.
- Imagery archived by an operator at the request of the media or the public—90 days.
- Imagery archived by an operator for a research request—may be deleted immediately following its transfer to the requester.
- Imagery archived by an operator and identified as valuable for training or education may be stored indefinitely or deleted upon the conclusion of training.
The same policy also notes that retention times may vary due to factors such as, "system or network health, compression efficiency, changes in technology, or changes to MnDOT’s needs."
As shown in figure 3, both storage space and anticipated needs were cited by more than half of the agencies as reasons for choosing the amount of time that recordings are kept by default. That is, the time that the recordings are kept even if specific clips are not saved longer for specific purposes, such as training or study data.
Figure 3 : Chart. For agencies that record most feeds by default, basis for length of recording.
(Source: Parsons Brinckerhoff)
The agencies were asked if there was a desire to keep some recordings longer than current storage space allowed. Most respondents indicated that there was not a desire to retain video longer—even if additional storage space was available inexpensively.
Transportation Management Centers that Sometimes Record
For those TMCs that are operating under a policy of only recording under limited circumstances for specific purposes (SOMETIMES), the following observations are relevant.
An example of an approach for selectively recording video comes from Minnesota in the years prior to 2008 when they started recording continuously. They assessed the needs and opportunities for limited recording and added Digital Video Recorders (DVR) to cover groups of cameras accordingly. For example, when installing a new cable median barrier, they started recording cameras that monitored it. Not only did it record the performance of the barrier for internal use, but also video was released of a prevented head-on collision when the gentleman who had been saved took to the media to acknowledge the value of the barrier. Minnesota also strategically deployed recording for the change of a High-Occupancy Vehicle (HOV) lane to a High-Occupancy Toll (HOT) lane and monitoring top crash locations.
Capability Maturity (Transportation Management Centers that Sometimes Record)
The Capability Maturity Model in table 3 for TMCs that sometimes record has some similarities to the corresponding one for TMCs that always record (table 4), however, there are important differences as well. Similarities including moving from an ad hoc system through having and following written documentation to performance management and proactive looking to improve and simplify. Another similarity is electronic file organization. However, there are differences in the content that are specific to different needs of TMCs that always record and those that only sometimes record. The tables have been kept separate for the completeness of their respective sections.
Table 3: Capability maturity model for Transportation Management Centers that sometimes record video.
|Ad hoc decisions on which types of events to record, when to start recording, who decides to start recording, and how files are saved.
||Have written policy with agreed-upon types of events to record and who has the authority to make and delete recordings; file management system or standardized, searchable file naming convention.
||Document annual uses of recordings including value added and necessary staff time and technical resources to provide; consider needs to revise policies and practices, including reaching out to stakeholders to see if select recordings would support related functions such as engineering studies; consider process simplification.
Length of Time Recordings are Kept (Transportation Management Centers that Sometimes Record)
Literature review uncovered that the general practice in a security application of CCTV is to keep recordings for 30 days, though some may choose lesser amounts if a screening process is in-place to know that a recording will or will not be valuable. For traffic management applications, however, outreach to the agencies uncovered a much larger variation in length of time that recordings are kept as shown in figure 4.
Figure 4: Chart. Length of time agencies that record under limited circumstances keep recordings.
(Source: Parsons Brinckerhoff)
Best General Practice
While there can be ancillary benefits for having recorded video available as a courtesy to law enforcement agencies, TMC staff need to be clear that the primary purpose of traffic cameras and recording technology is for traffic management.
The feedback received from agencies and TMC operators underscores that the length of retention frequently varies and that it is often influenced by the use of the selected recording. However, across agencies there were no real firm trends; it varied widely even when the anticipated uses were the same.
For training videos, as an example, one agency said that training videos are the only type of recording kept for more than one day. Another agency notes that after-action reviews and trainings are scheduled as soon as possible and that recordings are then no longer retained. Yet another agency notes that there is no specific time duration for keeping training material.
The agencies were asked if there was a desire to record more frequently or to keep some recordings longer than current storage space allowed. Almost three quarters of respondents indicated that there was not a desire to record more or to retain video longer. However, some respondents noted that enforcement or other agencies might be interested in more frequent recording or longer retention, but it was beyond their purview. One noted that enforcement agencies could record the live video feed provided to them by the transportation agency.
In addition, there was no correlation in those not interested in recording more frequently versus the length of the time they typically kept recording.
Uses of Recorded Video for Security and Law Enforcement
For traffic management, real-time situational awareness of vehicle flows is the key. For security and law enforcement, records that can be used for evidence are also vital. DOTs now often have large networks of cameras and, policy permitting, they could be recorded. TMCs typically share video with law enforcement agencies and may be colocated with law enforcement agencies. It is important to consider and discuss the differing needs, including operational needs, as well as legal frameworks when there is this overlap. The New York area Triborough Bridge and Tunnel Authority gave the following scenario as the basis for discussion—a box truck is stopped next to a bridge pier. From a traffic management perspective, the need is to dispatch roadside assistance, monitor queuing, and provide traveler information. However, from a security perspective, there is a need to view the truck closely to help assess if it might be an intentional stop and have explosives. In the latter case, having a record of evidence is crucial. The decision on whether to dispatch a tow truck, law enforcement, or both could rest heavily on the initial use of the nearest camera. Even within a roadway agency, there may be security-focused cameras covering bridge piers and office building doors. For these cameras, recordings are also important for investigations. However, there are different privacy concerns for the doors of buildings since individuals are shown through the normal course of their work.
When knowledge that video is available spreads among local agencies, additional requests occur. New Jersey DOT (NJDOT) once processed a request from a Society for the Prevention of Cruelty to Animals (SPCA) for footage from a temporary trailer-mounted camera that had been set up to monitor a construction detour.