India drafts first breakwater standard for climate-resilient ports

India is writing its first national engineering standard for breakwaters, the offshore structures that shield ports from waves and storm surges. The Bureau of Indian Standards (BIS) is developing a code that would require a minimum 50-year service life and account for 100-year return-period storms and projected sea-level rise, two people familiar with the process said.

The draft, formally titled IS 4651 (Part 6), is under public comment, Abhishek Pal, a scientist in BIS's civil engineering department, told Mint. Until now, engineers designing breakwaters for Indian ports have relied on foreign references such as the U.S. Army Corps of Engineers' Coastal Engineering Manual and the European Rock Manual, as well as project-specific consultant practices.

“The proposed code requires breakwaters to be designed with a minimum service life of at least 50 years while accounting for 100-year return-period storms, storm surges and projected sea-level rise over the next five decades,” one of the people said. A 100-year storm has a 1% chance of occurring in any given year.

Traditional coastal infrastructure design used historical records of waves, tides and storms. Climate change is making those records less reliable, the person added, so the new standard embeds projected sea-level rise and more extreme weather into the engineering framework.

Mumbai Port Authority chairperson Dr. M. Angamuthu said the code is flexible enough to handle India's diverse coastal conditions. “It provides guidance on the assessment, rehabilitation and life extension of existing breakwaters; encourages periodic updates to climate parameters; promotes structural health monitoring and life-cycle maintenance and factors in navigation safety, sedimentation, maintenance dredging, constructability and other marine considerations during implementation,” Angamuthu said.

The move comes as India expands its maritime infrastructure under the Sagarmala program and Maritime Amrit Kaal Vision 2047. The country has 13 major ports and more than 200 non-major ports, with several new projects under way. Breakwaters are among the costliest port components, dissipating wave energy and creating calm harbour waters for safer navigation and cargo handling.

Despite the rapid port expansion, India lacked a standalone breakwater engineering standard, the second person said. The code is being developed with input from public and private port operators.

The proposed standard aligns Indian practices with evolving global norms followed by major maritime nations. The draft is under wide circulation for public comments, Pal said.