In Deep Water: South Delhi ResidentsIn A Fix Over Flooding Of Basements

Delhi: 7 Feb, 2022 (Times of India)

 

New Delhi: With some perplexity, and some poetic licence, residents in south Delhi could well be saying, ‘Water, water everywhere, nor anywhere to dig’. The Central Ground Water Board has warned of depleting underground water and described the problem in many south Delhi areas as critical and semi-critical with the water table more than 50 metres below the surface. And yet in Greater Kailash, Amar Colony, New Friends Colony, National Park (Lajpat Nagar IV), Chittaranjan Park and other places, the water seems to lie just a few metres below the ground, percolating into basements and posing a structural risk to buildings.
Bhavna Gupta’s basement at E Block, Greater Kailash II has seen constant flooding for two years. Fearing for the structural integrity of her house, she recently decided to engage a structural engineer.

Residents like Gupta have been left helpless by the flailing efforts of official agencies to manage the problem. “The civic authorities claimed they had resolved the problem last year, but there has been no real change. In fact, things are getting worse,” claimed Bharat Ahuja, E Block resident. “Now residents of neighbouring CR Park are reporting the same problem of inundation of basements.”

While trying to alleviate the woes of GKII residents, CGWB carried out a study of the area and said in its final report mid-2021 that the inundation was the result of three causes: closure of all domestic tube wells by Delhi Jal Board, thereby reducing groundwater withdrawal, construction of protection walls underground at the Greater Kailash metro station from surface to 32 metre below it, thereby reducing the natural groundwater flow by acting as a subsurface dyke since 2018 and the heavy rains in 2020.DMRC refused to comment on the possibility of the subsurface dyke at GK metro station being a factor, pleading that the matter was sub-judice.

After its study of a 5sq km area straddling Hauz Khas and Kalkaji Mandir and further Jahanpanah Park and Astha Kunj Park further south, CGWB suggested extracting groundwater to contain the seepage. It also said asked for the installation of 7-8 piezometers (a device that measures the pressure of groundwater at a specific point) to monitor suitable locations in Kalkaji tehsil. It then said it would help to have 5-6 heavy duty tubewells to extract water after a geophysical survey to pinpoint the extraction point.

Residents, however, alleged the borewells were dug randomly after at low-lying points without the recommended geophysical survey. “That is the reason why three of the six borewells didn’t react well to water extraction,” claimed Gupta in GK II. “Also, the depths of the borewells are 200 ft deep while the purpose was to extract water from an aquifer lying at 18-20 ft.”
CGWB had recommended 18-20 hours of water extraction, but, as Sanjay Rana, president of GKII Welfare Association, reported, “Water is being drawn out for just seven hours daily from 9am to 4pm. We have requested DJB to pump out three time the current volume and lay a pipeline to carry the water to the reservoir.”

A DJB official insisted such steps were being taken. “Two projects to carry water from GK II to the underground reservoir have been cleared for GK II. One is under way, the other will start soon,” said the officiaBut these measure seem specific to GKII and do not explains an identical problem in Kalkaji, where the Purnima Sethi Hpital has been flooded by seeping water, or at SDMC’s multi-level car parking in Sarai Jullena adjoining New Friends Colony, which hasn’t been operationalised fully since its completion in 2017 due to seepage in the basement level.

Abhishek Dutt, SDMC councillor from Andrews Ganj, confirmed receiving requests for help from residents of National Park and Amar Colony. They approached DJB and CGWB for alleviation of their woes and sent an email to the lieutenant governor. “We expect a meeting at the LG’s office on Monday,” said Dutt. “Initially, 7-8 houses suffered seepage, but more families began complaining afterward.”

Surinder Singh Bindra of National Park said that after bearing the seepage for eight months, the residents approached DJB, whose officials visited the area. “We were told the problem was due to a rise in the water table and the subject was dealt with by CGWB. We have been running from pillar to post since September without success.”

A few kilometres away at New Friends Colony, Alpana Gupta said, “Seepage in the basement is a regular feature during the monsoon. But since July last year, our basements are constantly flooded. Our house was constructed in 2014, but older houses in Maharani Bagh are reporting a similar problem,” she said.

A K Gosain, professor emeritus, department of civil engineering, IIT-Delhi, said a scientific study of the entire region should be carried out to clarify its geological characteristics. “The reason for oozing water in one area may be different from another area. For example, underground concrete construction is a local issue and cannot be a factor for all instances of inundation,” said Gosain. “The only solution is to monitor the system from all angles and then consider the implications of the interventions being made.”