Nearly 1,000 personnel headed by a senior officer repaired the Munak canal, which supplies over 500 million gallons of water from the river Yamuna to Delhi.
On the weekend, the Delhi government had sent an SOS to the Centre and the Supreme Court when protesters damaged the gates and controls of the Munak canal, forcing seven water treatment plants to shut down.
At around 4 am on Monday morning, soldiers removed protesters squatting at the canal and took charge of its repairs. Home ministry sources say the canal has been repaired "35 per cent" and will be restored completely only tomorrow.
Delhi Chief Minister Arvind Kejriwal, who had appealed to the Centre for help saying that Delhi had completely run out of water, tweeted his thanks to the army.
Fearing a water emergency, the Kejriwal government had moved the Supreme Court, which today rebuked city water minister Kapil Mishra for "sitting in the court" instead of talking to Haryana and resolving the crisis.
Worries about a severe crisis also led to the government shutting schools and offices.
Jat protests for reservation escalated to violence, arson and vandalism over the weekend in many parts of Haryana. Ministers' homes, railway stations, malls and shops were vandalized or torched, buses were damaged and road and train traffic was badly hit.
Home Ministry sources said there was a "complete breakdown in the state" and around 11,000 army and paramilitary personnel have been sent to the state.
Personnel of the Central Reserve Police Force or CRPF were mainly in charge of repair work.
The Saifabad water treatment plant and three important roads were fixed by CRPF personnel. The gates of many canals had been damaged by protesters, and these were also fixed.
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