Key challenges of Design & Construction in Creek Area of 765 kV D/C Hexa Conductor Based Lakadia Vadodara Transmission Project

The Lakadia-Vadodara transmission system is a key element in evacuating renewable power from western region of Gujarat state in India and is a major step towards accelerating India’s transition towards a greener economy.

The project consists of a 335 km long double circuit 765kV transmisson line having hexa bundle AAAC Zebra conductor. The line connects the 765kV new Lakadia and existing Vadodara sub-stations. This is among the longest green energy corridor transmission project in India. The paper describes the challenges faced in the construction of the project in a stringent timeline and severe RoW challenges. Moreover, the line passed through areas having high chloride content in the soil and a large creek area. The paper focuses on the major challenges faced in design and construction of the line in the creek area. The creek area couldn’t be avoided due to reasons of substantial increase in route length which would have severely impacted the economic feasibility of the project.

As a first step, detailed studies of the route were done to arrive at an optimised solution while still conforming to all the statutory requirements. At certain locations no historical data was available and new investigations had to be conducted in a very tough right of way (RoW) environment. In addition, temporary approach roads had to be constructed to access locations in the creek area through submerged land. Since these approach roads were temporary in nature, the complete work including foundation, erection and stringing of the structures had to be completed in a single working window.