The National Highways Authority of India (NHAI) will introduce mandatory independent design verification for critical bridges and other complex structures on national highway projects from 1 December 2026. The move aims to strengthen structural safety and improve design scrutiny before approval of major highway infrastructure projects.
According to a circular issued by NHAI, the new procedure will require selected bridge and structure designs to undergo independent verification by empanelled Indian Institutes of Technology (IITs), government technical institutions or reputed engineering firms. The requirement will apply to projects implemented under the Engineering, Procurement and Construction (EPC), Hybrid Annuity Model (HAM) and Build-Operate-Transfer (BOT) modes, along with other project delivery methods specified by the authority.
Structures Covered Under the New Rules
The independent design verification system will cover major river bridges with a design discharge capacity of at least 3,000 cubic metres per second. It will also apply to bridges and other structures with an individual effective span of 40 metres or more.
In addition, the authority may identify special structures that require independent technical scrutiny based on their complexity and project-specific requirements.
The new procedure establishes a uniform framework for reviewing structural designs across eligible highway projects. It is intended to ensure that important design elements receive additional technical assessment before final approval.
Procedure for Independent Design Verification
Under the prescribed process, contractors or concessionaires must first submit their designs to the Authority’s Engineer or Independent Engineer for review or approval, as required under the relevant contract.
They must subsequently propose three institutions or engineering firms from NHAI’s approved panel. The concerned regional office will select and approve one or more agencies based on the requirements of the project.
The appointed agency will independently examine design calculations, structural analysis and engineering drawings. Hydrological and hydraulic studies will also be reviewed wherever applicable, particularly for structures where water flow and flood-related considerations influence design requirements.
Contractors and concessionaires will be required to address the observations raised during the verification process. Necessary modifications must be incorporated with the approval of the Authority’s Engineer or Independent Engineer before the design receives final approval.
Contractors to Bear Verification Costs
The cost of independent design verification will be borne by the contractor. For projects where the requirement is introduced after the contract has already been awarded, the additional obligation will be processed as a variation or change of scope under the applicable agreement.
The rules will apply to new projects as well as projects awarded before 1 December 2026 where design vetting or proof checking has not yet started.
Projects in which the design verification process has already been completed will generally not be covered retrospectively. However, additional checks may be undertaken for particularly complex structures if the parties mutually agree to the requirement.
Implications for Highway Infrastructure Projects
The new framework introduces an additional layer of technical scrutiny for bridges and complex structures on national highways. Independent verification by specialist institutions is expected to support the review of structural calculations, design assumptions and hydraulic considerations before construction proceeds on eligible projects.
For contractors and concessionaires, the requirements will involve additional coordination during design submission, verification and approval. Project teams will also need to account for the verification process in their design schedules and budgets, particularly where the requirement applies to existing contracts.
By standardising independent design checks for specified structures, NHAI is seeking to strengthen design oversight across national highway projects and establish a consistent review process for infrastructure with complex engineering requirements.
