SHALINI SAKSENA speaks with experts about simple, cheap and timely solutions to waterlogging problems in Delhi-NCR

Back in 2013, the Comptroller and Auditor General of India, Shashi Kant Sharma, had ordered an audit of all flood control measures and the city’s drainage system due to the havoc that waterlogging causes in the Capital. The order had come on the heels of heavy rain crippling vehicular movement, damaging roads and flooding residential colonies like T3 Terminal of the Indira Gandhi International Airport.

Cut to 2018. The situation remains the same. Delhiites will tell you that every year, new areas are added to the already long list of waterlogging due to rains. On the Delhi Police website as many as 156 areas have been identified!

Given this scenario, it is  not surprising to see screaming headlines like ‘Delhi goes under’. While Delhiites look forward to cool showers that bring down temperatures from a scorching 47° C, what is not welcome are the traffic snarls and hours spent in jams.

In 2010, scientists at the Central Road Research Institute had conducted a study related to road congestion. The study had thrown horrific numbers. A daily commuter spends six years in traffic jams in Delhi on an average 30-year career! This is not all. If you live in Gurugram or Noida and commute at least five days a week to work, the figure could go up to eight years! The CRRI estimated a Rs 100 crore loss by assuming an average figure of Rs 2,000 as daily earnings of car-riding commuters. The study notes that a standstill traffic situation occurs “at least five days in a month” in Delhi. These numbers include jams on non-rain days but it does give one an estimate number of manhours lost. All because there is Government apathy when it comes to the problems that the common man faces due to waterlogging.

While many want separate lines to be laid out in the city, costing thousands of crores, some experts opine that there’s no such need provided there is proper management. The problem is that many of the stormwater drains carry sewage. In other words, what the Capital lacks is the basic infrastructure. Why  do stormwater drains carry sewage is a question that the concerned departments have to answer.

One is told that there are two main reasons why this happens. First, it is the citizens themselves who are flouting the bylaws with impunity. “There are many low-lying residential complexes. When it rains the water from the roads runs down towards their homes flooding them. The solution is simple — ask the local contractor to lay a pipe and connect it to the sewer line. What they don’t realise is that their selfish action inconveniences others and in some ways them too. This is because sewer lines are laid to carry certain capacity of waste depending on the locality. But if a pipe is connected to the sewer line to carry flood water, it is not going to help since the sewer pipe is not built to do that. Hence the problem,” Vijay Motwani, former Special DG, CPWD tells you.

Second, when the local authorities do it. This is done under duress and pressure from the top. Though the concerned authority is aware that this will lead to problems in the future they have no option but to give in.

“When individuals do it, it is because they have no respect for the bylaws. When the authorities do it, they give in to the pressure,” Motwani says.

Despite the means and the technology available to rectify the waterlogging issues, Delhi becomes one big sewer drain during monsoons because we lack foresight. A drainage master plan for NCT of Delhi prepared by a team from the Indian Institute of Technology-Delhi (IIT-D), highlights the need for the city’s stormwater drains to remain free of sewage and solid waste.

Professor AK Gosain, Department of Civil Engineering, IIT-D who recently gave a talk on: Solutions to save Delhi from getting flooded even with little rain tells you that desilting and cleaning of the pipes is around 50 per cent of the solution.

“The major problem is that the infrastructure that is supposed to carry out the stormwater from the areas to the disposal locations — the Yamuna, they need to function properly. Sometimes, these pipers get clogged; they are not cleaned and the slopes are not maintained — there are adverse slopes — becoming bottlenecks,” Gosain explains.

He is quick to point out that increasing the width of the pipes is next to impossible even though it may be of help to a certain extend. Most of the pipes are in areas over which are occupied so there is no scope of expansion. Going deep also comes with challenges.

“There will come a situation where going very deep will require pumps to push the water up ultimately into the Yamuna. This is an expensive proposition. Increasing the width is not feasible,” Gosain says and opines that there is a need to understand that as one keeps paving the areas more each year, for the same amount of rainfall the volume it generates as run-off keeps increasing.

“For example: If 50 years back, it was 1 cm of rain was creating a run-off of half cm, then the remaining was going into the soil. If this increases to 95 per cent, means that the whole rainfall becoming run-off and this is increasing the volume. The same rainfall is now creating more volume due to urbanisation. Though the drains have remained the same, the volume they are carrying is more and are not capable of carrying the run-off today,” Gosain says.

However, he doesn’t agree that the problem is due to a rise in the rainfall in the Capital. “Statistically, if one were to look at the past rainfall figures it would stand out that the intensity has risen and may become even more intense due to climate change implications,” he says.

And the waterlogging in the bylanes, it is due to lack of proper drainage. Also, back in 1982, if one were to compare the land use with what it is today, it is more now. The areas that have been paved is higher. Earlier, large amounts of water was going into the soil. Today, paving has reduced the run-off. What was supposed to go as run-off is going into the drains which are of course not capable of carrying.

Giving the example of waterlogging at Minto Bridge each year and the problems associated with it, the Professor tells you that one had go down to create an elevation for the buses to pass under the railway bridge; it was depression that was created as per the design.

“All the water that collects there is supposed to be pumped out since the water can’t flow against the gravity and the slope. If the pumps are not functioning, there will be waterlogging;  — either the pumps are not of an improper size or they are not pumping out as fast as they should be. It is more of a management issue. This is true for many other underpasses in the Capital,” Gosain tells you.

This means that whenever the water goes into a depression then there is an urgent need to pump it out. Under gravity, one is using the slope of the land and is also true for the drains. “Once the water is in the drains it can flow out as per laws of gravity. Therefore, there is an apprehension of going too deep. Going deep would mean that it may be entering the Yamuna at its lowest level. This can’t happen since, in such a situation, the river will start backflowing. The same is true for any road. If a depression is being created, from the top of the road the water may run-off but it will get will trapped if there is a depression leading to waterlogging,” says Gosain.

Gosain’s solution: First, immediately desilt. This can only be done if there is access to drains. There are large number of drains running for many kms which are covered, no one knows what is happening there — how much of it is occupied with silt? If there is no access to these drains how can there be a claim that desilting has been done? Even if the desilting has been done for say a 2 km long drain, if the lower level has not been desilted even for 5 feet, the whole exercise is useless.

“Every year, the only check is how much muck has been taken out. Nobody checks whether the drains are working properly. A simple check involves taking a tanker full of non-potable water and empty it out upstream and see whether the water is coming down or not. No one bothers to do so. Then there are modern means of checking. The latest technology can be used. A CCTV camera can be out on a robot to check whether the drain has been properly cleaned or not,” Gosain tells you.

Second, delink stormdrains with sewage drains. A sad situation in Delhi is that all the stormdrains are supposed to be dry during non-monsoon months are carrying sewage. Only if stormwater drains are dry, it is possible to clean them up. But since they are carrying sewage, this is not possible.

“As a city Delhi needs to ensure, which needs to start at the top and systematically check the smallest drain and see whether it is carrying sewage. if it is, it can immediately be checked and the DJB can trap it and take it into a sewer line. If there is no such line, they need to lay one down. The worst part is that people think that stormdrains are meant to carry sewage. This is one reason why are rivers are so populated. If the sewage is checked at the city level, nothing will empty out in the Yamuna and the river will automatically get cleaned and will revive. At present, we are doing everything the other way round,” Gosain says.

Motwani tells you that the problem in Delhi is that divided into municipal limits — NDMC, South, North and East Municipal Corporations. “The engineers working here are primarily responsible to tackle the problems the city faces. But they are building engineers and may not necessarily have the know-how to deal with the problem related to the garbage disposal and waterlogging. Also, not all the problems surfaced together. But now, given the present technology available, we do have the solution. When the wrong was being done, we probably didn’t know what the repercussions would be,” Motwani says and opines that there is a need to create awareness by first teaching the local authorities who then need to teach each household how to treat garbage.

He also tells you that the solution to this problem lies in segregating wet garbage from the dry. “If people start separating garbage, it will take care of the problem to a large extent. Since people are not likely to do so, the least they can do is segregate the waste in their respective homes before disposing it off. The dry waste like empty cans and glass bottles can be sold off. This also helps the ragpickers who are otherwise seen sifting through piles of garbage with bare hands. Whenever you dump garbage anywhere, it is bound to find its way into the drains thereby choking them leading to no solution,” Motwani says.

Factfile

Rainfall and traffic jams are synonymous with Delhi-NCR. Here’s a look at some problem points this year:

• July 13: The Palam, Lodhi Road, Ridge and Ayanagar observatories recorded 14.2 mm, 44.2 mm, 118.4 mm and 71.4 mm of rain respectively. There was waterlogging under the Tilak Bridge, Mill flyover, Dhaula Kuan flyover and near the Welcome metro station. There were problems at the Zakhira flyover, Kamal T-Point, Anand Parbat, Y-Point old railway bridge at Kishan Ganj, Azad Market and near the old iron bridge at Dharmpura.
• July 15: 45 major roads like Bahadur Shah Zafar Marg, Mathura Road, Lala Lajpat Rai Marg, Mahipalpur Road and Munirka saw snarls due to waterlogging. At some places like  as Minto Bridge, Chattarpur Andheria Mor and Karol Bagh, traffic had to be diverted due to heavy waterlogging or trees falling.
• July 26: Several parts of Ghaziabad and Greater Noida were submerged in knee-deep water. People going to offices were the worst hit as traffic at many places like AIIMS, Hauz Khas, Wazirpur, Shalimar Bagh, Rohini and other low-lying areas in Dwarka were hit. Rains ensured that the traffic leading to the Film City in Noida Sector 16 (A) crawled. Several housing societies in Greater Noida, Vasundhara and Vaisahali reported heavy waterlogging.
• July 31, 2018: Heavy rains caused waterlogging at the entry gate of the soon-to-open Bhikaji Cama metro station, due to which a portion of a footpath adjoining it had sunk a little.
• August 10: Heavy rains lashed Delhi that led to traffic snarls and congestion in various parts. At peak rush hour, commuters were stuck in traffic in and around areas like Lutyens Delhi, Sarita Vihar, Lajpat Nagar & Greater Kailash.
• August 28: Heavy rain accompanied by lightning was reported around Indira Gandhi International (IGI) Airport, Teen Murti Bhawan and RK Puram among other areas in the city. Some areas in Dhaula Kuan and Palam Mod were waterlogged following heavy rainfall.
• September 1: The traffic was affected on Mathura road, Shershah road, Mathura road to Bhairon road, Purana Qila road, Bihari colony, Maharishi Raman Marg, Teen Murti Lane, 11 Murti and Girdhari Lal Goswami Marg near post office due to excessive waterlogging. Waterlogging was reported at Lajpat Nagar market, Pant Nagar bus stand and IP Marg near police headquarters. The traffic was closed on Bhairon road both ways due to waterlogging.
• September 7: Heavy rains lashed parts of Delhi leading to traffic jams at Rajapuri Chowk and Palam Flyover. Traffic was slow on Wazirabad Road, Bhajan Pura Main Road and Khajuri Chowk due to waterlogging.
• September 23, 2018: Major city junctions and underpasses were waterlogged in Gurugram following two hours of rain.