[Representational image]Reuters

Things are going to get difficult for residents of Chennai as the four reservoirs from where the water-starved city sources its water are likely to go dry in a few days. Chennai Metropolitan Water Supply and Sewerage Board (CMWSSB) will also cut its supply from 500 million litres per day to 420-470 million litres per day in the next few weeks.

According to a Times of India report, those living in central Chennai, Porur, Alandur and the surrounding areas will face problems because the Chembarambakkam reservoir is running dry with official figures showing storage at 53 McFt against storage of 1996 McFt in 2016.

The Red Hills reservoir, located in the Thiruvallur district of Tamil Nadu, is also likely to dry out by the end of the week with storage at 33 McFt against the full capacity of 3300 McFt.

A senior official at Metrowater told the News Minute that the water situation in Chennai is "bad" and added that the city would face a crisis if the south-west monsoon fails. "If it does not rain and groundwater is not recharged, borewells will start failing and then it will be a crisis," he said adding that south and central Chennai would be the worst hit areas.

From where will Chennai get its water?

The water supply will depend on how much of groundwater is available at the Metrowater sources in Tiruvallur and Neyveli. Metrowater is also considering sourcing water from their desalination plants at Nemmeli and Minjur. 

"We will divert water from other sources to affected areas to ensure there is no shortage. Our 100 MLD desalination plants at Nemmeli and Minjur are running at full capacity," a senior Metrowater official told TOI.

The two plants in Nemmeli and Minjur produce around 195 million litres of water per day presently. After the Red Hills reservoir dries out by the end of this week, water is expected to be sourced from the Neyveli basin, Tiruvallur farms and rainwater stored in Sikkarayapuram quarries, which account for around 270 million litres of water per day.

Quarried sites located in Outer Ring Road in Chennai contain 3000 million litres of water, TOI had reported earlier. Metrowater officials also considered pumping water through a pipeline from these sites to the Chembarambakkam treatment plant to be distributed to residences in Chennai Central.

The Metrowater official said that water sourced from Porur lake will be supplied to those residing in Kodambakkam, Valasaravakkam and Alandur zones from July this year. All other lakes in Chennai have been affected due to the sewage that flows into them.

"We also explored the option of drawing from the Manimangalam Lake (located in the Kancheepuram district). The lake water is potable but there is no distribution point nearby for water to be delivered to residents. The nearest distribution point is 20km away," the official added. 

Metrowater has also provided a 40 percent increase in the supply of free water through tankers in an attempt to help the low-income groups. The number of free tanker trips has increased to 5,000 a day from the earlier 3,000 a day to meet the needs of the residents.

Chennai has been grappling with acute water scarcity since several months after a 60 percent deficit in the northeast monsoon. The state of Tamil Nadu has been declared drought-hit with the state facing its worst drought in 140 years.