Forgotten for 15 years, drain which led to waterlogging found in south Delhi

The discovery of this 113 metre-long drain led to a series of meetings and letters exchanges between govt departments.

A mystery drain, the existence of which everyone had forgotten for 15 years, and which, as a result, had not been cleaned for that span of time, was responsible for the flooding seen in tony south Delhi neighbourhoods such as Hauz Khas, Vasant Kunj and Malviya Nagar after the Capital received 230 millimetres (mm) of rain in 24 hours till 8.30am on June 28.

The drain was found under Sri Aurobindo Marg. (HT PHOTO)

The multiple agencies responsible for the maintenance of the Capital’s drainage system scrambled to find out the cause of the flooding. They did find it eventually — a drain no one knew about.

And it was a discovery that led to more questions, and highlighted how easy it is for things to fall between the cracks in a Union territory with multiple agencies responsible for the same thing in different parts of the city.

“We found that there was a huge drain under Sri Aurobindo Marg. There were four large drain pipes, each over one-metre wide that we found were laid by Delhi Metro Rail Corporation (DMRC). The work was done well, which is why it could take sewer and water run-off for over 15 years without getting choked. However, it was surprising that no agency knew about its existence or was maintaining it for so many years,” said an official from the Public Works Department (PWD), who asked not to be named.

The discovery of this 113 metre-long drain led to a series of meetings and letters exchanges between PWD, DMRC, Municipal Corporation of Delhi (MCD) and the Malviya Nagar MLA’s office, some of which HT has seen.

It emerged that DMRC, while building its underground Yellow Line (it connects Samaypur Badli in Delhi to Millennium City Centre in Gurugram) in 2009 blocked a brick barrel drain but added four large steel pipelines for drainage. But even DMRC has no record of the agency from which it took over the brick drain, or the agency that had been maintaining it previously. Interestingly, DMRC also has no records of which agency it handed the drain over to.

“During construction of cut and cover tunnel for Yellow Line Metro in Green Park under Sri Aurobindo Marg in the year 2009, DMRC dismantled the previously existed drainage system consisting of big brick barrel drain and replaced it with four metal pipes laid at about 3-4 metre depth below ground level...This whole drainage system is laid about four metres below the ground level and taking discharge of surrounding areas like SDA, Green Park, Hauz Khas as well as sewer also,” one letter said.

“To facilitate construction activities, DMRC suitably diverted the flow of the brick barrel drain by providing 1.4 metre (wide) pipes of adequate capacity to deal with the discharge being dealt by the brick barrel drain and this work was completed in the year 2009. As far as we know, the brick barrel was being maintained by MCD,” a DMRC spokesperson said.

He added that after the heavy rainfall of June 28, DMRC attended a meeting of multiple agencies where no one was willing to take on the responsibility of cleaning and maintaining the drain.

That’s evident in the content of some of the letters.

“PWD is only maintaining storm water drains incidental to the PWD-maintained roads and the maintenance of big brick barrel drains and deep drainage lines is not the mandate of PWD. Since the ownership of the roads are still with MCD, the above deep drainage lines consisting of big brick barrel drains, which are a part of continuous drainage system is within the ownership of MCD only. The above deep drainage lines were never taken over by PWD and moreover, PWD is also not equipped with the required method of deep sewer cleaning as the same requires specialized labour and machinery for deep sewer cleaning,” a letter from PWD said.

Finally, DMRC had to step in.

“Despite not being our responsibility, in order to alleviate the difficulty being faced by the residents, DMRC, as a special case, took up this exercise and deployed a specialised team with necessary safety equipment...to clean the pipes as well as the associated chambers. Thereafter, DMRC has written to PWD as well as MCD along with all the necessary details like the drawings, video footage, etc. for regularly maintaining these pipes/drains,” its spokesperson added.

MCD did not respond to requests for a comment. PWD officials said it was decided only last month that the drain will be maintained by MCD from now on.