Maintenance and upkeep of National Highways (NHs) including bridges, structures, etc. are undertaken through different modes. In Engineering Procurement and Construction (EPC) contracts, the contractors maintain the road during construction period and thereafter during Defects Liability Period-cum-Maintenance Period. In Design Build Finance Operate and Transfer (DBFOT) / Hybrid Annuity Mode (HAM) Contracts, the concessionaires maintain the road during construction period and thereafter till end of concession period. Concessionaires of Toll Operate and Transfer (TOT)/ Special Purpose Vehicles (SPVs) of INVIT agreements maintain the road during the concession period. Rest of the National Highways stretches are generally maintained by contractors of Performance Based Maintenance Contract (PBMC) and Short-Term Maintenance Contract (STMC).
Visual as well as equipment based periodical inspection, evaluation and monitoring has been mandated for National Highways including bridges to ensure that structural integrity of various components of NHs is maintained through timely repair/rehabilitation intervention. Structural health monitoring on real time basis is also carried out in some very important bridges. Ministry has also sanctioned Indian Bridge Management System (IBMS) for monitoring and maintenance of the bridges and other structures on the entire NH network in the country.