Preventative maintenance is carried out to prevent the deterioration or failure of facilities through continuous and systematic inspection and detection. A rigorous program of preventative maintenance can extend the service life of a road, bridge, underpass or civil structure. This ensures that the maximum value is realised from the initial capital investment. Additionally, regular maintenance proves more cost effective than occasional major repair. The concept of preventive bridge maintenance is built on the understanding that a program of multiple relatively small repairs and activities will keep the structure in good condition. Thereby the large expense of major rehabilitation or replacement is avoided.