Rain rain go away, our cities can't keep the water at bay!

Water logging on city streets
Water logging on city streets

Breaking news! The monsoon is here! It hit Kerala on June 1 and with that put an end to newspapers stories on drought in India highlighted by pictures of farmers standing on cracked earth and staring up at the sunny skies. However, very soon there will be Page-1 picture spreads of water-logged cities with traffic jams and harried people titled "The city is drowning"!

Let's not blame the media. We are as responsible for hyping up this situation as is the media. People in cities have forgotten how to welcome the monsoons. While the heat is sweltering, we pray for rains but when the rain comes, we don’t know how to use the water and we only focus on the commotion that it causes. Will the roads be clear or will there be jams? Will we get an auto-rickshaw easily or will we have to pay five times the rate? That's what we are concerned about and it's the same across most Indian cities.

Metros under water

Bangalore had its first pre-monsoon shower on May 23 this year. Rather than people being out on the streets singing and dancing in the rain, they had to worry about flooded major connecting roads, water logging and falling trees. The situation is quite similar in other parts of India as well.

When Delhi hosted the Commonwealth Games in 2010, a little extra rain and release of water from a barrage upstream threw the national capital into chaos. There was water everywhere - from the popular Tibetan flee market near the Inter-state Bus Terminus to the ground floor of the Commonwealth games village, which housed athletes from different countries. Despite several warnings, the Games village was constructed in the Yamuna floodplain, which was meant to absorb excess rain water. The construction left no space for the water to seep into the ground and therefore caused flooding.

Life comes to a standstill in most cities

In August 2000, floods in Hyderabad washed away 77 slums near the Hussain Sagar lake. Curiously, the Musi river that runs along the city, did not have much water. This meant that flooding only happened due to local rainfall and not due to the rain in an upstream area, which would've caused the water in the river to rise as well.

The epitome of urban floods happened in Mumbai on July 26, 2005. The city had 37 inches of rainfall within a day, most of it within five hours. One-third of the city was flooded and all essential services, including the robust suburban rail network, were shut down. About 900 people were swept away and many went missing. For the first time, floods did not mean just reduced mobility for a middle-class office goer in a city, but death in real terms.

Chennai, situated near the sea, faces floods almost every year, thanks to good rainfall and bad drainage. "Closing of schools due to flooding every year is common in many parts of Chennai," says an article. 

Surat in the western state of Gujarat, an otherwise planned city, faced a major catastrophe in 2006. 150 people died and a number of farm animals drowned when the gates of the Ukai dam opened to release excess water from the region upstream of the city.

1999 was the year of floods in Kolkata. "The city turned into a lake. With water mixing with dirt and sewage overflows, the stench in many areas was unbearable," said a news article. There were several news reports asking why a century-old crumbling sewerage was being blamed when 30-year-old new areas were also getting flooded.

The wrath of 'Purandar'

In Indian mythology, Indra the rain God, also has another name-Purandar which means destroyer of cities and forts. "When the town planning of a certain city was faulty, Indra manifested his Purandar form to destroy it. The present destruction of cities is thus easily explained," says environmentalist Anupam Mishra. The rain God pours water designated for each region. If we do not have a proper container of hold that water, it will just flow off or get stuck on roads like it does now, he says.

Meteorologically, there is no major upward or downward trend of rainfall for the last 200 years, but a decrease in rainfall in the last 20 years with a contrast record of increasing floods has been experienced in Chennai. Thus, the oft-cited reason by administration for urban floods - heavy rainfall in a few hours - does not hold. It is only an excuse for bad planning in the cities.

The root cause of the problem is that cities have become less dependent on their own water sources. The number of water bodies in all major cities of India has drastically come down over the last three decades (see graph below).

Drop in the number of water bodies (lakes and ponds) in the metros

'Mumbai Marooned' a citizens' report on the 2005 Mumbai floods says that the builder-politician nexus has knowingly and intentionally suffocated the city's open spaces for commercial purposes. This loss of and subsequent commercialization and concretization of open spaces has meant that water, which previously could seep into the soil has practically nowhere to go, leading to flooding, it says.

Instead of introspecting and understanding the reasons for their sources drying up, the cities looked outside. Bangalore turned to the Cauvery, Hyderabad to the Krishna and Delhi to the Ganga and now all the way up to the Giri near Renuka in Himachal Pradesh. "City administration feels that water demand cannot be fulfilled locally. So the city with more political clout goes farther away to get its water. Meanwhile, property rates keep rising and politicians and builders make money by trying to sell off floodplains as prime residential destination," says Anupam Mishra. "But when it comes to monsoon, you can't dictate God that we already have water for our need so please give us only this much rainfall," he says.

These floodplains and lakes in the low-lying parts of a city, did not just fulfil the water needs of a city, but also drained it off the excess rain water that poured there. When construction blocked the path of water, it led to water-logging on the city roads. The blame then fell on the storm water drains which in most cases, were designed very long ago and were not capable of handling the excess water that seeped into the ground. The 'Mumbai Marooned' report says that the city's drainage system was designed in the early 20th century for a maximum rainfall of 25 mm per hour, assuming that half the rain would be absorbed by the soil and only half would flow into the drainage system.

With the onset of rampant and indiscriminate urbanization, most areas are now either paved, concreted or asphalted. As a result very little rainwater is absorbed into the ground. Thus even at one inch per hour, the drainage system is having to cope with almost twice its intended capacity, says the citizens' report.

Natural drainage or the slope of a city was never kept in mind when cities were planned, says Manoj Mishra of Yamuna Jiye Abhiyan, an NGO in Delhi. "Ring road in Delhi is the finest example of that. There are no culverts to discharge excess water. There was a stream feeding into the Yamuna where the busy ITO road stands today and one can see that it is flooded first when rainfall happens. Not just this, all bus stands in Delhi are situated on lakes. If we tamper with the area where rain water is supposed to rest, then we might as well be prepared for the wrath of floods," he says.

"Typically, the rain water that drains off an empty plot of land (run-off) is 10%. However, build a house on the same site and almost 90 per cent of the rain falling will runoff as storm water. No storm water drain can handle so much flow," says S. Vishwanath, an expert on rainwater harvesting, especially when they are already polluted by sewage, industrial and household waste. "The government should start cleaning drains in February at least so that passage for rain water is clear. But they wake up only in May when monsoon is right in the face and then too, debris collected from the drain is left on the banks of nullahs for it to flow back when rain comes," said Manoj Mishra.

The latest fad to have caught the fancy of the powers that be is river channelisation. The belief that taming the river into a proper channel by constructing walls around it can save us from floods has proved wrong time and again but the government has turned a blind eye to it. Embankments as these walls are called, create havoc in the flood plains of the Kosi river in Bihar every year when the river changes its course and breakes them, rendering thousands of people homeless. Even though the government is fully aware of this, embankments costing crores of Rupees have been constructed around the Sabarmati river in Ahmedabad, all in the name of beautifying the river zone. 

The present disastrous floods in central Europe, which does not even have a monsoon, saw rivers diverting up to three kilometres from their designated channels even with little rainfall, flailing the whole idea of channelisation. The Western world which introduced channelisation and development near rivers to us is itself facing its consequences and even removing embankments at a great cost now. The State of India's Environment report on floods brought out by the Centre for Science and Environment shows that all the money spent on flood mitigation has only resulted in more floods because the government focussed only on constructing more and more embankments.

The way out

Water harvesting in lakes and ponds is no traditional wisdom, says Anupam Mishra. "It is a very contemporary solution, time-tested and need of the hour, not just to mitigate floods but also to fulfil our water requirements locally," he says. "Rain water is actually meant to become ground water so every citizen has to take the initiative to recharge it," says Mishra.

When somebody constructs a house it is their responsibility to take care of the excess water from that plot of land, which would otherwise go into a storm water drain or else create water-logging around the plot, says Vishwanath. The solution is a proper rain water harvesting system in the house itself. It would not just replenish ground water but also improve its quality and mitigate flooding. 5% of any built up area, be it an apartment complex or individual house, if used for rainwater harvesting, can mitigate floods and also reduce water bills. Some towns in Germany have made it mandatory for construction projects to take responsibility for their excess run-off or pay more for putting pressure on storm water drains.

Rain water harvesting is what all individuals can do but the administration can contribute to this effort as well. Storm water drains could be utilized as a water harvesting measure rather than just act as carriers of excess water to the sea, says Sekhar Raghavan, head of Rain Centre in Chennai. The Centre provides technical and logistical support to people keen to implement rainwater harvesting measures. "Recharge wells can be constructed in open spaces around storm water drains. Water in drains can be intercepted and directed to these wells ," says Raghavan in his proposal to the Chennai municipal corporation. In areas where open spaces are not available, recharge wells can be dug in the drain itself under the man-hole so that it can be cleaned also from time to time.

Re-laying of roads as per the natural drainage patterns needs to be carried out, feels Mishra. Hydrology expert Professor A. K. Gosain from IIT Delhi is preparing a model of a sustainable drainage network for Delhi. "Any new construction can thus be carried out keeping the model in mind," said Gosain. The modelling process will take about six months once they have all data in hand, he informed.

Every drop contributes to floods, so permeable gravel or stone lined parking spaces and footpaths that can absorb water rather than concretized floor would also help. And there is no substitute to planting trees in whatever area is available to promote absorption of water and control run-off of soil.

Post By: ravleen
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