A recent Clear Roads synthesis project surveyed state DOTs with winter maintenance programs about their best practices for avoiding corrosion of electrical connectors. Common agency practices for reducing corrosion include installing a waterproof or weatherproof connector, using dielectric silicone and dielectric grease for sealing connections, and applying a heat shrink tubing to cover the crimped […]
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Corrosion and Connectors Don’t Mix
The lights on wing plows, tow plows and other winter maintenance equipment require electricity to operate, and the electrical connectors used in these assemblies are exposed to the elements during winter operations. While failures in winter equipment lighting systems can be the result of mechanical or environmental issues, a more significant concern is the impact of corrosion. A connecting wiring harness (plug and socket) begins a 12-hour shift dry and tight. But by the end of the shift, the connector may begin to loosen, allowing chemicals, abrasives, and road material to enter the connection and begin to break it down.
The goal of this project was to gather information through a literature search and survey that explored the availability of a connector assembly that can avoid corrosion and survive the plowing environment for an entire winter season.
The deliverables from this project will included survey results and a final synthesis of the information gathered.
Mechanic/Operator Training and Training Needs for Winter Maintenance Equipment
Within many state transportation agencies, there is a lack of training on pre-trip and post-trip equipment inspection. There is also a lack of training on diagnosing and correcting mechanical problems in the field and in the shop. All of this results in increased periods of equipment downtime and delayed response to storms.
The goal of this project was to identify and synthesize the training materials on these topics that have already been developed by state DOTs, equipment manufacturers, and winter maintenance industry organizations for reference by Clear Roads.
This project determined the extent to which training material on these topics exists and what competencies the existing training material addresses.
Resources, Practices and Needs for Weather Forecasting to Facilitate Winter Road Maintenance
State DOTs have limited budgetary resources for road weather forecasting; however, agencies need consistent, accurate weather information to facilitate the timely and appropriate deployment of winter maintenance operations.
This project’s goal was to determine how agencies meet their weather forecasting needs, how effective their forecasting resources are in facilitating road maintenance decisions, and what kinds of information or other resources agencies perceived they need to improve their winter response.
This synthesis produced a report based on surveys of state DOT central office staff as well as field personnel that addressed:
- The forecasting services, coalitions, meteorologists (on-staff or consultants), and other means that agencies use to obtain weather forecasts and road condition information.
- The extent to which agencies consider their forecasting sources and methods to be accurate, effective, and valuable, as well as perceived challenges and deficits.
- The local information gathering efforts (such as mobile weather sensors on maintenance vehicles) that agencies use to supplement broader weather forecasts.
- The methods agencies use to translate predicted weather severity into specific maintenance actions or responses.
- How agencies convey timely weather information to operators in the field.
- Perceived challenges and potential roadblocks to improving the acquisition of accurate and timely weather data and effectively translating it into the appropriate maintenance response.
Inventory and Use of Salt Spreading Systems
Each state has various methods and types of delivering salt to the road network. Clear Roads member states are interested in learning what equipment their peers in other states are using.
The goal of this synthesis was to gather information from Clear Roads states to update an inventory—first completed through Project 12-05—of the states’ spreader systems and to provide the rationale as to why they are used.
Through a survey of Clear Roads member states, this synthesis provides a snapshot in time of the material spreader systems used by 16 agencies. The majority of survey respondents were satisfied with individual features and functions and reported overall satisfaction with their chosen system. While price was a significant motivating factor in system selection for some agencies, other agencies sought specific features, and one agency developed special specifications for the manufacturer to meet at a designated price.
Appendix B of the synthesis provides individual respondents’ assessments of their spreader systems.
Use of Prewetted Solid Materials for Roadway Anti-icing
Historically pre-treatment or anti-icing has been accomplished with the use of liquid products such as CaCl, MgCl, or brine. Recently, a transition has been made to higher pre-wet rates for solid applications because many crews seem to believe that this is a more cost effective method than liquid.
Clear Roads members were interested in learning about state DOT’s experiences with using prewetted solids or slurries for roadway anti-icing as an alternative to traditional liquid anti-icing. Specifically, they wanted answers to the following questions.
- What is the prevalence of this technique and what are the conditions when this approach may be appropriate?
- What is the cost/benefit of this approach when compared to traditional liquid applications?
- Is there an increased environmental impact to this approach? ie. more chloride on the road or more importantly off the road?
Through a literature search and survey of Clear Roads states, this project produced a synthesis report which summarizes state DOT practices related to prewetting of solid materials for anti-icing, including a description of which materials are used, what prewet rates and/or slurry rates are used, the most appropriate weather and road conditions for this technique, effects on the environment, regulatory issues, and success stories, challenges, and lessons learned.
Effective Snow and Ice Personnel and Equipment Management for Storm Activation
The right time to activate snow and ice personnel and equipment is an important factor in both safety and budgeting. Activating too much too early can cause unnecessary budgetary expenses, while activating too late can cause safety-related issues. Determining the right time and percentages of personnel and equipment to activate is relative to many factors.
Clear Roads members are interested in answering the following questions.
- How do states determine how many personnel/equipment to activate as the storm approaches?
- What percent activation is utilized during times of borderline temps with wet road conditions?
- Do states utilize storm monitors to relay information to field forces on conditions?
- At what time are the resources secured after an event?
A literature review and a survey of 25 Clear Roads states indicates that most agencies summon half or more of their workforce to come in before a storm arrives. Meteorologists have become increasingly involved in winter maintenance programming, and a broad range of sophisticated systems, weather data and forecast sources are drawn upon in activation decisions, which are usually made at the district or regional level.
Activation and deactivation procedures are data-heavy activities. Many states have specific thresholds (fixed numbers) for air temperature, pavement temperature, precipitation levels and other factors that trigger activation. Decisions about when to deactivate forces (send crews home) tend to be driven by a combination of fixed value thresholds and field observations. Current conditions are given more weight than forecasts, with the significant exception of precipitation forecasts. The increasing role of meteorology in winter maintenance activities suggests they may be becoming more data-driven.
Calibration Accuracy of Material Application Equipment
With the increasing emphasis on protecting the environment from foreign materials and chemicals, reducing the amount of anti-icing and deicing chemicals and accurately reporting the amounts applied are gaining importance. However, the accuracy of salt application equipment is varied. Loss of calibration coding, moisture of salt, size of salt grains, temperature of hydraulic fluid, flight on the auger not being full of material, and wear on equipment all have an effect on the accuracy of measurements of salt application of snow plows.
Clear Roads members are interested in learning about state DOTs’ current practices and certainty concerning the accurate calibration of solid material (deicer) application equipment.
Through a literature search and survey of Clear Roads states, this project produced a synthesis report that summarizes DOTs’ experience with calibration of their spreading equipment.
Maintenance Vehicle Conspicuity
Improving highway safety and increasing mobility are always of utmost importance to a transportation agency. When DOT maintenance vehicles are operating during severe winter weather and/or operating at night, the risk of motorists coming into contact with these vehicles increases dramatically.
Clear Roads would like to learn which color schemes, including retroreflective taping patterns, are best for DOT vehicles and equipment to maximize conspicuity in both winter and summer operations?
This project will produce a synthesis report which summarizes domestic and international research that highlight the most effective paint colors, lighting, and retroreflective taping patterns used to enhance the conspicuity of state DOT maintenance vehicles, airport vehicles, emergency vehicles, law enforcement vehicles, and other commercial vehicles.
In particular, this study will focus on where and and how conspicuity treatments are most effectively placed on a vehicle; the most effective combination of conspicuity treatments; and the appropriate balance of conspicuity and safety during both daytime and nighttime hours.
Monitoring Stockpiles of Solid Winter Maintenance Materials
Finding the right method to take frequent, accurate measurements of stockpiles of solid winter maintenance materials can be challenging for transportation agencies. Measurement practices can be time-consuming or fail to produce measurements that are accurate enough for the agency to rely on. Without accurate measurements of the materials on hand, an agency can face shortages of the solid winter maintenance materials needed to see it through a winter season.
The goal of this project is to create a synthesis of best management practices for the accurate measurement of solid winter maintenance materials, and other solid materials, using technology and non-technology based methods.
This project will produce a synthesis report that summarizes best practices for the periodic accurate measurement and reporting of covered and uncovered stockpiles of solid winter maintenance materials. The synthesis will also include practices used to measure uncovered stockpiles of other solid materials such as aggregates and agricultural products. Information for this project will be gathered through a survey of winter maintenance contacts in all 50 states and a literature search.