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24 Core Asset Data Business Rules Performance Measures and Standards Geography Deficiency Criteria and Standard Design Standards Location Maintenance Standards Referencing Standard Procedures Program Categories Funding Levels Inventory Analytical Tools Analysis Parameters Inspection Unit Costs Life-Cycle Costing Needs Simulation Service Life and Benefit/Cost Analysis GIS Query and Deterioration Analysis Tools Models Traffic Heuristic Decision Database Query and Discount Rate Rules Reporting Tools Value of Time Sketch-Planning Impact Accident Costs Optimization Analysis Tools Default Average Crash Statistics Specialized Databases Risk Analysis Speeds Default Auto Network Models Occupancy Work History Decision Support Programmed Needs and Solutions Work Evaluation of Options Investment vs. Performance Trade-offs Source: NCHRP Report 545. Figure 4.1. Context for an analytical toolbox. though continually being relaxed, are nonetheless important systems use data from other management systems or require factors that tend to restrict system functionality and scope. project-specific inputs to perform analysis. Systems in this Lacking the single, comprehensive asset management category include systems for needs identification; testing system, agencies must instead use a variety of different informa- alternative policies for scoping, timing, or design; evaluation tion systems, together with manual and/or spreadsheet ap- of projects or strategies; project prioritization; lifecycle cost proaches, to support implementation of asset management. analysis; and risk analysis. This section discusses five basic types of tools for supporting Risk Assessment--This category includes tools specifically the Interstate Asset Management Framework: designed to calculate risks of system failure, predict conse- quences of risk, and assist in prioritizing investments in Investment Analysis--These systems provide general risk mitigation. guidance on the performance predicted for one or more Results Monitoring--This category includes systems that asset types given a specified budget level. help monitor performance and costs over time, such as on Management Systems--This category includes pavement, costs and effects of maintenance and construction actions. bridge, and maintenance management systems, as well as others. These systems are designed to support a broad range 4.2 Asset Management Data of functions for one or more asset types. They generally have inventory and condition data and may contain additional Federal and state transportation agencies have been collect- functionality described for the other categories listed here. ing highway related data since the 1950s. Although the reasons Needs and Project Evaluation--Needs identification and for data collection have varied, typically data have been col- project/treatment evaluation are central functions of an asset lected to support infrastructure management practices, com- management approach. An extensive set of systems has been ply with Federal mandates, support research, and support developed for supporting these functions. Typically these Federal resource allocation.

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25 This section provides an overview of data available for IHS thicknesses). Between 35 to 40 percent reported that they Asset Management, focusing on Federally mandated data sets collect detailed inventory data (e.g., pavement layer material and other types of databases commonly maintained by state properties, subgrade type, and drainage). DOTs. Federally mandated data sets have significant potential The survey also showed variances in terms of the types of for supporting the framework because all agencies have access pavement condition data collected. All of the agencies sur- to the same data in the same format. However, the framework veyed collect IRI and rutting data. Over 90 percent collect is flexible so that agencies can augment Federal data with data data on fatigue/alligator cracking and transverse cracking, from their other databases. While agencies typically follow while 84 percent collect data on longitudinal cracking in the Federal guidelines for data collection, even when collecting wheel path. In addition, 29 percent of the agencies in the sur- data that goes beyond Federal reporting requirements, in vey collect Present Serviceability Index (PSI), 69 percent col- some areas there are no specific standards on how certain lect surface friction, and 56 percent collect a composite index. types of data are to be collected, stored, or reported. The fol- (These figures are for hot-mix asphalt (HMA) pavement. lowing subsections are organized by asset type, with additional They vary for other types of pavement.) subsections on mobility, safety, and environmental data. Almost every aspect of the Interstate Asset Management Structure Data Framework requires data of some kind. Fortunately, as de- scribed below, most agencies have already made significant National Bridge Inventory (NBI) data investments and have access to a wide range of data. It is The NBI is a Federally mandated database of bridge inven- recommended that agencies work to fully leverage these exist- tory and conditions compiled by state DOTs for submission ing data resources. to FHWA. It contains data on all bridges and culverts on or over U.S. roads that are greater than 20 feet in length, and Roadway Data data on many tunnels. The NBI data set contains condition Highway Performance Management System (HPMS) data by bridge component: deck, superstructure, substruc- ture, channel/channel protection, and culvert. It also contains The HPMS is a national transportation data system pro- data on a bridge's functionality, such as underclearances and viding detailed data on highway inventory, condition, perfor- load posting information. mance, and operations. It describes functional characteristics, traffic levels, and pavement conditions for all IHS sections. Pontis Bridge Management System (BMS) Since its initial development, the HPMS has been modified several times. It has recently undergone a major reassessment, In contrast to the situation with PMS, most states (over 40) referred to as HPMS Reassessment 2010+. The objectives of this license the AASHTO Pontis BMS, making this system the initiative were to reflect changes in highway systems, national defacto standard for BMS data in the United States. The Pontis priorities, technology, and to consolidate and streamline database contains all the NBI data items, as well as more reporting requirements. The final assessment report (9), detailed element-level inspection details. For example, the NBI described in Appendix A, lists additional data items to be file contains a single condition rating for a bridge's super- added to the HPMS. The current version of the HPMS includes structure. The Pontis database contains additional data on the two measures of pavement condition: PSR and IRI. HPMS distribution of conditions by condition state for each struc- 2010 will contain additional measures of rutting/faulting and tural element of the superstructure, including elements such cracking, consistent with AASHTO standards for pavement as girders, stringers, floor beams, etc. AASHTO has developed data collection. standard element descriptions and condition state language, referred to as "Commonly Recognized (CoRe) elements" for Pavement Management Systems (PMS) Databases use with Pontis and other BMS (10). However, states using Pontis may specify their own elements and most have done Most agencies collect pavement data required to run a so, supplementing or replacing the CoRe element language. pavement management system (PMS). PMS databases are Further, most agencies that have implemented Pontis have needed for supporting the Interstate Asset Management added agency-specific data items to the Pontis database. Framework, but there is no standard format for how this information is collected or stored. For example, in a recent Other Structure Data survey of 45 state DOTs performed by Applied Research Associates, more then 80 percent reported that they collect The NBI file described above contains inventory information basic pavement inventory data (e.g., pavement type, lane for many tunnels and inventory and condition information width, shoulder type, shoulder width, number of lanes, layer for some culverts (where the length of the culvert measured

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26 along the centerline of the roadway is over 20 feet long). (13) provides examples of best practices for a number of assets, There are no other Federal databases containing data on non- and recommends specific inventory and condition data items bridge structures, including tunnels, culverts, retaining walls, to collect for assets including signs, guardrails, and pavement sign support structures, and other structures. However, a markings. Also, this guide presents a set of criteria for deter- number of agencies store data on other structures in their mining what data to collect for an agency's assets that is par- BMS. The collection of data on these assets varies significantly ticularly applicable to assets classified here as safety features. between state DOTs. FHWA has published Guidelines for the Installation, Main- Mobility Data tenance, and Repair, of Structural Supports for Highway Signs, Luminaries, and Traffic Signals (11). This guide recommends The HPMS is the major source of mobility data for the IHS, performing an element-level inspection for these structures, particularly at a national level. It contains average annual daily similar to that commonly performed for bridges, and recom- traffic (AADT) data for all segments and additional functional mends specific elements that should be inspected for each data needed for modeling mobility-related measures. The structure type. Separately FHWA has developed the Highway FHWA Highway Economic Requirements System--State Ver- and Transit Tunnel Inspection Manual (12) with recommended sion (HERS-ST) takes HPMS data as an input and can be used inspection practices for tunnels. AASHTO has published the to model mobility measures. All DOTs have developed some Asset Management Data Collection Guide (13). This document form of database for tracking highway inventory and traffic contains recommendations regarding data collection for a data in addition to what is required for HPMS reporting. There number of assets, including drainage assets. There are no are no standards for how this additional information is col- Federal guidelines for asset management data for culverts, lected or stored. NCHRP Web-Only Document 97 (18) details retaining walls, or noise barriers, though Appendix A describes best practices in collecting IHS mobility and operations data. recent work describing available systems and approaches for these assets. Safety Data Fatality Analysis Reporting System (FARS) Safety Feature and Facility Data NHTSA National Center for Statistical Analysis maintains Many state DOTs maintain some form of inventory of their the Fatality Analysis Reporting System (FARS). Established in safety features and facilities, ranging from paper files and maps 1975, FARS contains data describing all fatal accidents occur- to computer database systems. There are no Federal standards ring on public roads in the United States. Data included in the for collection of asset data for safety features and facilities, and FARS database are collected by state and local police officers, no real consistency in the data available from one agency to coroners, emergency medical services, and state motor vehi- another. The most common approach to using this to support cle administrations. Data describing approximately 40,000 asset management is through development of maintenance fatal accidents are added to the FARS annually. levels of service (LOS) as part of a performance-based budget- ing or maintenance quality assurance program. This approach is detailed in NCHRP Web-Only Document 8 (14). LOS values Highway Safety Information System (HSIS) are typically calculated by maintenance program (e.g., roadside, The FHWA's Highway Safety Information System (HSIS) drainage, vegetation, etc.) and can be reported either on a letter is a multistate safety database that contains accident, roadway scale (A through F) or numeric scale. inventory, and traffic volume data. The University of North Four resources detailed in Appendix A describe the state of Carolina Highway Safety Research Center and the FHWA the practice in asset management data collection for safety maintain the database. The participating states--California, features and facilities. NCHRP Synthesis 371 (15) details data Illinois, Maine, Michigan, Minnesota, North Carolina, Utah, available for signals, lighting, signs, pavement markings, and Washington--were selected based on the quality of their culverts (treated as structures in this report), and sidewalks. data, the range of data available, and their ability to merge The 2006 white paper "The Use of Highway Maintenance data from the various sources. HSIS is used to study current Management Systems in Statewide Highway Agencies" highway safety issues, direct research efforts, and evaluate the describes a survey of maintenance management data and effectiveness of accident countermeasures. systems performed in 2005 (16). Further, the report on the recent Transportation Asset Management Domestic Scanning State Crash Data Systems Tour conducted as part of NCHRP Project 20-68 details best practices examples for asset data collection in a number of Crash data are collected by police officers at the scene of agencies (17). The Asset Management Data Collection Guide crashes. Every state has a unique system for collecting crash