158 ■ Transportation Research Record 1772 Paper No. 01-3323 The engineering community has long recognized the need for adequate maintenance of drainage structures. However, despite several regional and national studies that highlight the damaging effects of poor mainte- nance, few agencies have improved their inspection and maintenance schedules. Although inadequate funding is the most plausible reason for this scenario, the lack of formal procedures to survey drainage assets, determine their conditions vis-à-vis their functional objectives, and objec- tively quantify their condition also adds to the problem. Described is a practical prototype maintenance quality assurance (QA) procedure for evaluating the adequacy of drainage asset maintenance in a consistent manner. Key components of the QA procedure are discussed in detail. A software program developed to implement the various components of the QA procedure is described. The program is a simple tool with which to check the condition and functionality of drainage assets at any time. Designed to handle both surface and subsurface drainage assets, the program can be implemented at any level of maintenance jurisdiction. A complete description of the program’s functionality, from the selection of inspection units to the generation of maintenance quality ratings, is pro- vided. Implementing the presented concepts could result in a substantial economic benefit for the implementing agency. Surface and subsurface drainage systems combat two different problems arising from a single source, namely, the presence of water. Surface drainage provides for the interception, collection, and removal of water from road surfaces and slope areas to reduce the risk of hydroplaning and flooding, as well as to minimize user in- convenience. Subsurface drainage systems, on the other hand, are installed to keep moisture that infiltrates the pavement structure from weakening and degrading the pavement materials. Whereas the primary focus of surface drainage is on enhancing safety of the roadway, that of subsurface drainage is on enhancing its perfor- mance and reliability. Nevertheless, considering that surface drainage plays a major role in controlling the amount of water available to infiltrate the pavement structure, it shares a symbiotic relation- ship with subsurface drainage. Further, because both systems help improve the overall performance of the roadway, they need to be an integral part of quality assurance (QA) programs for highway maintenance. Improper maintenance of surface drainage systems has readily observable and sometimes catastrophic outcomes. However, the ill effects of improper maintenance of subsurface drainage systems take longer to manifest and are, as a consequence, overlooked by many agencies. Many state and national agencies have found that a high percentage of in-place subsurface drainage assets are com- pletely nonfunctional (1–3). Some failures occur even before the pavement becomes operational. Failed subsurface drainage assets not only affect the functionality of the drainage system but also could have an adverse effect on the performance of the roadway. For example, it is well accepted that an improperly functioning sub- surface drainage system causes more harm than if no drainage were provided at all. When a pavement test section with subdrainage shows signs of deterioration, it is worthwhile to examine the functional- ity of the drainage system. Failure to do so will confound the results and may lead to erroneous conclusions. Unfortunately, agencies may lack readily available performance histories of the drainage structures. Although the drawbacks of improper maintenance of drainage sys- tems are known, there are many obstacles in implementing formal QA programs to assess drainage installations. These obstacles include the high initial cost of implementing such programs and a lack of will- ingness among responsible personnel. Also affecting implementation are the lack of (a) simple, reliable, and objective procedures for eval- uating quality, (b) an organized and consistent set of maintenance activities, and (c) a procedure with which to quantify the benefits of a systematic program. Although the former set of obstacles must be dealt with internally by an agency, a well-organized QA procedure that fully articulates all the components involved could go a long way in overcoming the latter set of obstacles. NCHRP Report 422 presents a prototype QA procedure for the maintenance of highway facilities, including drainage assets (4). Modern quality management theories and techniques were incorpo- rated into the procedure. It consists of a series of 24 components or action items divided into two phases of work. The first phase con- tains components associated with developing a customized QA rating based on level of service (LOS), and the second phase is the field implementation and closed-loop operational phase. This procedure was used as a baseline to customize a prototype QA program for maintenance of drainage assets. The scope of this research was limited to developing an LOS- based rating of drainage assets, which involved providing guidance on program components such as performance goals for each asset; individual asset and asset group weighting factors; data collection, analysis, and reporting; and a rating system. Prototype software also was developed for easy field implementation of the procedure. The benefits to implementing such a program include a uniform approach to maintenance and need-based and judicious disbursal of available funds. Quality Assurance Procedure to Assess Maintenance Adequacy of Drainage Assets Jagannath Mallela, Patricia A. White, Leslie Titus-Glover, and Kelly L. Smith ERES Consultants, 505 West University Avenue, Champaign, IL 61820.