Cover Image

Not for Sale

View/Hide Left Panel
Click for next page ( 72

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement

Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 71
Fixed Costs and Activity-Based Costing Fixed costs are those costs that do not vary with output, such as costs of administration and buildings. Ideally, your agency should have an accounting system that determines fixed and variable costs by maintenance activity and by product and service category. This is known as "activity-based costing." If your agency does not have such an accounting system, eventually you may want to implement activity-based costing to identify your fixed and variable costs by activity, product, and service. HARDSHIP FACTORS In addition to outcomes and resources, the third major group of measures needed for customer-driven benchmarking is hardship factors. These are factors outside the influence of maintenance crews. Examples of hardship factors are the following: Weather, Terrain, Traffic, Absence of shoulders along roads where work is performed, Average travel distance to work sites, and On-street parking. You need to prepare to collect data on these kinds of hardship factors because these will be assessed alongside outcomes and resources used. Weather In most states, weather varies considerably from one part of the state to another. Some states have wide extremes in weather that are partly a function of geography. Mountains, plains, deserts, heat island effects of urban areas, and proximity to oceans and large lakes are just a few factors that influence weather. It is desirable to adjust outcomes based on differences in weather from one location to another. Ideally, one should store data on 73

OCR for page 71
Chapter 3: Measurement weather conditions present at the time maintenance work is performed. To be more specific, standard daily work reporting should be augmented with weather data--at a minimum, the type and quantity of precipitation that occurred during the day and the high, low, and mean temperature. The drawback to further data collection is that it requires additional effort on the part of crew leaders to record this information, which detracts from getting their jobs done. An alternative approach to crew leaders recording weather data is to gather data from other sources and to combine it in a database with accomplishment and resource utilization information reported in daily work reports. There is extensive weather-related information available from the National Weather Service and state meteorological agencies. Weather data includes temperature; precipitation (rain and snow); wind direction; wind speed; humidity; and other information. Weather information is collected at selected sites throughout a state, but not necessarily in every county. Therefore, if you want to benchmark at the county level or a at lower organizational level, you will probably have to interpolate weather data from information collected at existing weather stations, unless maintenance personnel record weather conditions at the time they work. Another potential source of weather information is the Roadway Weather Information System (RWIS). Most states that experience snow and ice conditions have a RWIS. These systems consist of a set of pavement surface temperature sensors; subsurface sensors; and regular weather sensors (air temperature, wind direction, wind speed, humidity) at various locations along the roadway network. RWIS roadside units continually monitor weather-related pavement conditions and weather conditions. The data is collected and transmitted to a service bureau or to the transportation department that has responsibility for the roads. RWIS data can also be analyzed and extrapolated to counties, areas, and garages throughout a state. 74

OCR for page 71
Geographic Information Another hardship factor that affects maintenance productivity and outcomes is terrain. Mountainous and hilly areas are likely to affect maintenance outputs and outcomes differently than will flat areas. Information on terrain is readily available from both government and private-sector data sets. Most state DOTs have access to a geographic information system (GIS) that has information on terrain. However, information in a digital map often is not adequate for recording the type of terrain or other geographic information that affects maintenance outcomes in different locations. The reason is that a digital map is often a bit map, which is not in a form that allows manipulation of data concerning attributes of the roadway. More useful is roadway attribute data, which describes the type of terrain and other geographic features present where a section of road is located. Most if not all state agencies have a highway database containing this information. Ideally, terrain data will be included in the attribute database of the GIS and linked to a roadway centerline. It should be possible to transfer terrain data to the database in which you will be keeping information for benchmarking. Then, when work is performed, you can associate terrain and other geographic data with the data used to measure outcomes and resource usage. Roadway Attributes Certain roadway attributes affect the productivity and outcomes of maintenance work--for example, the presence of shoulders makes it easier for crews to park their vehicles and work on roadside safety features such as guardrails and signs. In the absence of shoulders, work zones will probably need to be established, which requires blocking off a lane of traffic and takes time that could otherwise be spent performing maintenance work. Data concerning roadway attributes such as shoulders will be found in the agency's roadway feature inventory database. Every state and most cities and counties will have data on the presence or absence of shoulders along various sections of road. 75