Karnaphuli Water Supply Project

The Karnaphuli Water Supply Project is a major infrastructure initiative undertaken by Chattogram WASA (CWASA), with financial support from Japan International Cooperation Agency. This landmark project aims to meet up to 80% of the potable water demand of Chattogram, significantly improving urban water security and public health.

In this post, I am sharing a series of images highlighting key components and engineering features of the project:

  • Image 1: A butterfly valve (blue), used for flow regulation and isolation within the pipeline system.
  • Image 2: A double orifice air valve installed on a 400 mm diameter pipeline, designed to release trapped air and maintain efficient flow.
  • Image 3: A gate valve, typically used for on/off control of water flow in the network.
  • Images 4–7: The water bridge crossing over the Halda River, consisting of a 1200 mm diameter steel pipeline—an important structural element ensuring uninterrupted transmission.
  • Images 8–13: Overcrossing sections of the 1200 mm diameter steel pipeline, demonstrating the complexity of alignment and integration with existing infrastructure.
  • Final Image: A rapid air valve installed on a 1200 mm diameter ductile iron (DI) pipeline, essential for protecting the system from air accumulation and pressure fluctuations.

These components collectively illustrate the scale, technical sophistication, and engineering excellence involved in delivering a sustainable water supply system for the city.














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