Levels of Service in Winter Maintenance Operations: A Survey of State Practice Prepared for Clear Roads Pooled Fund Study Prepared by CTC & Associates LLC WisDOT Research & Library Unit August 12, 2009 Transportation Synthesis Reports are brief summaries of currently available information on topics of interest to WisDOT staff throughout the department. Online and print sources for TSRs include NCHRP and other TRB programs, AASHTO, the research and practices of other transportation agencies, and related academic and industry research. Internet hyperlinks in TSRs are active at the time of publication, but changes on the host server can make them obsolete. To request a TSR, e-mail [email protected] or call (608) 267-6977. Request for Report Level of service is a measure used by transportation agencies to develop guidelines, classify routes and coordinate winter maintenance activities. The Clear Roads winter maintenance pooled fund is interested in learning how snowy states are using levels of service to provide for motorist safety and make effective use of limited resources. As the lead state for the Clear Roads pooled fund, Wisconsin DOT asked us to document the state of the practice for the use of levels of service in winter maintenance operations. Summary We conducted a brief survey of three groups—SNOW-ICE listserv members, Clear Roads technical advisory committee representatives, and attendees of the 2007 National Winter Maintenance Peer Exchange—consisting of the following questions: 1. What are your agency’s service level classifications? 2. What performance measures are used to determine if operations have met level of service guidelines for each classification? 3. How are routes monitored to determine if LOS guidelines are being met? 4. How much time is devoted to monitoring activities? Fourteen state DOTs, one township and one Canadian agency responded to the survey, with one state DOT providing two responses. (See Survey Results on page 3.) Key findings from the survey include: Service Level Classifications • Half of the agencies (50 percent) use service level classifications that relate to average daily traffic counts. • Other approaches to establishing service levels include corridor significance (Michigan DOT), a single classification—bare pavement—for all roads (Maryland State Highway Administration), and a classification scheme that places Interstates in one class and all other roads in a second class (Massachusetts Highway Department). Performance Measures • More than two-thirds of the agencies (69 percent) use bare pavement, bare lane, bare wheel path, clear condition, or roadways cleared shoulder-to-shoulder as a performance measure. • Other performance measures used by agencies include customer feedback, return to near normal winter conditions, movement of traffic at a restricted rate, and enhanced traction. • One-quarter of the agencies (25 percent) do not use performance measures. • An in-progress Indiana DOT research project seeks to establish a standard performance measure. Route Monitoring • Agencies may use multiple approaches to monitor routes. Only two agencies reported that they do not monitor routes. • Almost two-thirds of the agencies (63 percent) use management staff to monitor routes to determine if LOS guidelines have been met. • Almost one-third of the agencies (31 percent) use field personnel to monitor routes. • Other approaches to route monitoring include post-storm meetings used by Minnesota DOT to discuss material usage and regain times and Ontario’s use of contract monitors to ensure contractor compliance with LOS guidelines. The township of Hamilton, N.J., and Washington State DOT use geographic information system mapping technology to monitor winter operations in real time. • Some states use reporting systems to track and assess LOS data: o Kansas DOT uses its Road Condition Reporting System to record LOS data. At the end of the season, LOS data is compared with data from the National Weather Service to determine if the effort expended by winter maintenance operations staff matched the severity of the winter. o The Maryland State Highway Administration compiles LOS data through its Emergency Operations Reporting System. o Minnesota DOT uses an automated timesheet program to track LOS data and generate a new performance measure, Frequency of Meeting Target, which shows how many times winter operations activities met or exceeded expectations. Reports are generated using the agency’s Work Management System to compare regain times to material usage per lane mile. o Washington State DOT continues to expand implementation of an automated data collection system by equipping winter maintenance trucks with precision material controllers and data collection devices that update a central internal database through cell phone, IP radio or Wi-Fi technology. The new system is expected to allow winter operations managers to more effectively determine road conditions over a given time period. Time Devoted to Monitoring • While respondents found it difficult to specify the amount of time devoted to monitoring, almost two-thirds of the agencies (63 percent) monitor conformance with LOS guidelines during or after each winter storm event. • Almost one-third of the agencies (31 percent) report no set schedule or procedure for monitoring activities or devote little or no time to monitoring conformance with LOS guidelines. 2 Survey Results The full text of each survey response is provided below. For reference, we have included an abbreviated version of each question before the response; for the full question text, please see the Summary on page 1 of this report. Indiana Contact: Kirk Carpenter, Snow and Ice Program Director/Supervisor I, (317) 234-5048, [email protected]. (See Appendix A for Indiana DOT’s roadway classifications and service objectives.) 1. Service level classifications: See Appendix A for INDOT’s Snow and Ice Control Policy. [Class I = Interstate routes and roadways with Average Daily Traffic (ADT) volumes over 10,000 vehicles per day, as well as other high priority roadways, including but not limited to those serving hospital facilities and other emergency service providers; Class II = Routes with traffic volumes between 5,000 and 10,000 ADT; Class III = Routes with traffic volumes of less than 5,000 ADT.] 2. Performance measures: Currently, there is no set performance measure standard. INDOT is currently engaged in a research project with Dr. Bob McCullouch of Purdue University in an effort to establish a standard performance measure. [See http://rip.trb.org/browse/dproject.asp?n=17950 for the entry in TRB’s Research in Progress database. This research project seeks to develop a performance standard that uses sensors at monitoring stations and weather conditions to identify the start of a winter event; changes in traffic flow/speed during and after the event; and the time when normal traffic flow and speed returns. The standard will take collected traffic data and compare it with the winter event severity index and winter event timeline. Various levels of service will be defined that should occur during the winter activity timeline. The time to a desired LOS is based on subjective analysis. Researchers will also develop a reporting tool, which uses INDOT geographic information systems maps to display the results, to report winter event severity and condition of traffic flow. Researchers have completed a literature review and evaluated environmental sensors, and are awaiting installation of the sensors to use in the upcoming winter. A winter storm index is also being developed, which will be based on previous work at INDOT and Accuweather research.] 3. How are routes monitored? It’s up to the unit foreman, district and subdistrict managers. Again, there is no set procedure. 4. Time devoted to monitoring? See answer to # 3. Iowa Contact: Dennis Burkheimer, Winter Operations Administrator, (515) 239-1355, [email protected]. (See Appendix B for Iowa DOT’s general guidelines and procedures for snow and ice removal operations.) 1. Service level classifications: A, B and C. 2. Performance measures: A and B level: Return to near normal winter conditions within 24 hours of the storm end. C level: Bare wheel path within 24 hours of the storm end, returned to near normal winter conditions within three days. 3. How are routes monitored? Self reported by Maintenance supervisors at each garage. 4. Time devoted to monitoring? Monitoring of operations is done by garage supervisors, District personnel and Central Office during winter storms. Kansas Contact: Troy Whitworth, (785) 296-7140, [email protected]. (See Appendix C for Kansas DOT’s route classifications.) 1. Service level classifications: Category I Routes: Multilane highways and two-lane highways with AADT over 3,000; Category II Routes: Two-lane highways with AADT 1,000 to 3,000; Category III Routes: Two-lane highways with AADT near or under 1,000. 2. Performance measures: We currently have no performance measures employed at this time. 3 3. How are routes monitored? We utilize field personnel to monitor road conditions and enter LOS data into a Road Condition Reporting System (RCRS). At the end of the season we go back and get winter index information from the National Weather Service combined with the LOS data entered in the field. From this information we can see if the effort expended during the winter matched the severity of the winter. 4. Time devoted to monitoring? LOS on routes is monitored during each event. The data on LOS is not compiled until the end of the season. It is difficult to get the winter index information and RCRS information compiled in a timely manner. Maine Contact: Brian Burne, Highway Maintenance Engineer, (207) 624-3571, [email protected]. (See Appendix D for Maine DOT’s corridor priorities and levels of service. These documents are older versions of Maine DOT’s policies. Documents that include the urban Interstate level are in the process of being modified.) 1. Service level classifications: Priority 1+ = Urban Interstate over 20,000 winter ADT.