Managing SADC Roads Agencies in the New Millennium: The Role of Road Asset Management Systems
The management of the Southern African Development Community’s (SADC) road network is a complex task which is often influenced by a variety of factors – technical, financial, social and political – which all enter into the decision making process at various levels of their roads agencies. In such an environment, the determination of optimal strategies requires the use of a rational “systems” approach to road asset management. This paper outlines the road management strategy that is being pursued in a number of countries in the SADC region. It then illustrates how these systems are being used at various levels of application to achieve the desired objectives of the road agency.
ON THE CONCEPT OF TOTAL HIGHWAY MANAGEMENT
The need for a total highway management system is defined in this paper. A highway system serves a set of objectives, such as provision of an adequate level of service, preservation of the facility condition, safety, economic development, and others. It consists of a number of physical facilities, such as pavements, bridges, roadside elements, and traffic control devices. The system is managed through operational functions of a highway agency, such as planning, design, construction, maintenance, and so on. The highway system can thus be envisioned in terms of a three-dimensional matrix of objectives, facilities, and functions, all of which interact with each other. The current trend of developing separate management systems for pavements, bridges, and maintenance activities is a piecemeal approach, because it ignores the needs of the total system. Consequently, many current systems are either conflicting or involve duplication, or both. Instead, individual management subsystems, such as pavement management, bridge management, and maintenance management, should be developed in proper coordination with each other and with a clear understanding of the requirements of the total system. With the rapidly developing new information and communication technologies, there is an opportunity for organizing a total highway system that can assist in managing highway facilities in a highly efficient and productive manner.
BENEFIT-COST ANALYSIS OF ROADSIDE SAFETY ALTERNATIVES
In recent years, benefit-cost (B-C) analysis procedures have been widely accepted as a rational method for evaluating safety treatment alternatives. Most methods of analysis employed to date have significant limitations, overstate the severity of accidents, and are cumbersome to use. An advanced B-C analysis model that incorporates numerous modifications to enhance versatility and improve determination of accident severity is described. Basic encroachment data on which the model is based are presented, and the applications and limitations of the model are discussed. An example of the use of the model to develop general barrier use guidelines is also included.