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Barrage across Narmada: promise of sweet water, worries about hilsa  

18th August, 2020 Environment

Context: The Gujarat government recently awarded the contract for a barrage project to a joint venture of Dilip Buildcon Ltd and Hindustan Construction Company Ltd. The Rs-4,167-crores Bhadbhut project in Bharuch is meant to solve freshwater problems in this region of Gujarat.


What is the Bhadbhut project?

  • It is planned to be a 1.7-km causeway-cum-weir barrage with 90 gates, across the river Narmada, 5 km from Bhadbhut village, and 25 km from the mouth of the river, where it flows into the Gulf of Khambhat.
  • The barrage will stop most of the excess water flowing out of the Sardar Sarovar Dam from reaching the sea and thus create a “sweet water lake” of 600 mcm (million cubic metres) on the river.
  • The barrage will also have a six-lane road that will connect the left and right banks of the river and provide shorten the land distance between two large industrial estates in Surat and Bharuch.
  • The project also aims to prevent flooding in years when rainfall is higher than normal. Embankments 22 km long will be made and will extend upstream towards Bharuch, from either side of the river.


Why was the need felt?

  • The main purpose of the project is to prevent salinity ingress. Due to the reduced flow of fresh water, saline seawater gushes into the Narmada estuary during high tide, thus increasing salinity along the banks.
  • The sweet water from the reservoir will aim to meet the residential and industrial water requirements of Bharuch, Ankleshwar and Dahej.
  • The project is part of the larger Kalpasar Project, which entails construction of a 30-km dam across the Gulf of Khambhat between Bharuch and Bhavnagar districts. The reservoir is meant to tap the waters of the Narmada, Mahisagar and Sabarmati.


Why are fishermen upset?

  • The barrage is expected to interfere with the migration and breeding cycle of hilsa.
  • A marine fish, hilsa migrate upstream and arrives in the brackish water of the Narmada estuary near Bharuch for spawning usually during the monsoon months of July and August, and continue doing so till November. Once the barrage is built, it is expected to block their natural entry.
  • Hilsa catch between July and September every year has dropped to 10-15 fish a day from the earlier 50-100 a day.
  • According to a study by Kolkata-based Central Inland Fisheries Research Institute (CIFRI), fish production from the Narmada estuary has fallen from 15,889 tonnes in 2006-07 to just 1,618 tonnes in 2014-15.


What is the government’s stand on this?

  • Fish passes have been planned for hilsa fish. The Kolkata-based CIFRI has been asked to study the migration patterns and they have already submitted a primary report.
  • Designs will be made by the EPC (Engineering, Procurement and Construction) contractor based on this report. Studies have been on for the last one year and it will take another year for the institute to submit its final report.
  • According to our estimate, the fish pass will be about 5 metres wide and that should be enough for this species to migrate into the estuary without any hindrance. The height of this fish pass will be decided on the final report of the institute.


How will fishermen from Bhadbhut, and villages that are located upstream, access the river?

  • The barrage will have a fishermen navigation channel that will allow fishermen owning boats and living upstream on the Narmada beyond the barrage to get access to the sea.
  • This channel will be about 10-15 metres wide and will have a gate that can be opened and shut as necessary.
  • The barrage design also has a navigation lock to enable any future plans to run a ferry service or boats under the inland waterway scheme.
  • The Inland Waterway Authority of India has given clearance for this project.