The waters that go down the drain

One of the most frequent and devastating natural disasters that India has had to face for several decades now and almost regularly is floods.

The floods may be due to a variety of reasons-cloudburst, heavy rains, washing away of bunds or even the phenomenon of urban flooding. The flooding seems to be in almost all parts pf the country and in almost all the states, including Karnataka and its capital Bangalore.  

While Bangalore never had to face the flooding that other parts of India sees or what just Uttarakhand just saw, it is the prime example of how unplanned activities can lead Nature to take its revenge  and this is  shown by frequent flooding of  Bangalore.

Bangalore’s streets and many low-laying localities, particularly in the and around the Koramangala-Challaghatta valley record regular incidents of urban flooding, inundating localities, washing away wife and property, flooding roads and lanes and eventually leading to overflow of storm water drains.

Flooding in Bangalore may seem strange as it is not near any sea, river or ocean like Chennai, Delhi, Kolkata or Mumbai. However, the death of the City’s only river-Vrishabhavathi-and the flow of sewage into it which till date remains unchecked has contributed greatly to the imbalance in outflow of water from the city.

The Vrishabhavati is chocked with debris, garbage, filth and most of all silt in several places and this has blocked the effective flow of water. A minor tributary of Arkavathy, this river flows in Bangalore and even till the 1970s it supplied water for domestic, industrial and no-potable purposes to people living adjacent to it, including several villages.

The Vrishabhavathi is joined by Survanavathi at the junction of Gali Anjeneya Temple on Mysore road but today neither of the rivers exist. Both are filled with sludge and sewage and even fishes and /or any marine life cannot survive. The oxygen levels in these waters are almost non-existent and poison gas and chemicals make up a large percentage, posing a danger to those living nearby.

The chemicals in the water also pollute the ground water and make them unfit for drinking. The destruction of the Vrishabhavathi is directly due to the unprecedented growth of domestic, commercial and industrial activities and the increased generation of  foul, waste and sewage water.

Studies of water bodies, tanks and drainage of Bangalore by IISC, Bangalore University, ISRO, BWSSB, Central Ground Water Board, Central Water Commission and independent studies have said that the watershed has to be preserved , protected and nurtured if the ecology of water management of Bangalore, which has gone haywire, has to be set back into place.

The total catchment area of Vrishabhavathi is estimated to be a little over 350 square kilometers. The length of Vrishabhavathi river from Peenya, where it is said to originate-another myth is it originates near Bugle rock in Basavanagudi- to the

place where it joins Suvarnamukhi in Bangalore urban district is about 52.5  kilometre.

During summer or dry seasons, the water flow in the Vrishabhavathi is reduced and more than 300 MLD of domestic sewage flows into it. This is further compounded by the discharge of upto 10 MLD industrial and chemical waste.

The failure of the civic agencies and the Government in taking a tough and uncompromising stand against such pollution as also its failure to stand firm against encroachment, particularly of wetlands tanks and storm water drains, has only worsened matters.

The story of another of Bangalore’s river-Arkavathi-is also frighteningly similar. The Arkavathy takes birth at a small pond in the Channakesava Hills adjoining Nandi Hills or the Nandidoorga range of hills.

Arkavathy tumbles down the hill and drains into the Chikkarayyappanhalli Kere. This is the first of the many tanks or reserviors built to hold the waters of the Arkavathy which then empties into several smaller lakes and forms the Nagarkere in Doddaballapur.

The Nagarkere was once upon a time sufficient to meet the drinking water needs of the entire Doddaballapur town and surrounding villages. The command area of the tank was 60

hectares. It had a storage storage capacity of 2.27 million cubic

metre (Mcum) but it is today reduced to just 1.5 Mcum, thanks to silt, bad management and encroachment.

Then comes the 6.89 km Hesarghatta lake, built by the Wodeyar Kings to supply drinking water to Bangalore, Today, this tank is almost dry and ironically villages on the periphery of this once magnificent water body are facing a severe water shortage.

What many are not aware of is that a smaller tank did exist at the place where the Hesarghatta stands today. This small stone structure to hold water was built during the reign of the Vijayanagar Emperor Achutadeva Raya. It was in 1894 that this water body was enlarged.

We can say that Hesarghatta became the first external source of water supply to Bangalore which till then met its needs from local lakes and tanks such as Dharmambudhi tiull 1895, Ulsoor till the 1960s, Sankey and Millers tanks. It was way back in 1989 that the Hesarghatta reservoir overflowed its bund. Since then, it has been downhill for this waterbody.

The Arkavathy then comes down from Hesarghatta and joins the Kumudavathy at Tippegondanahalli or TG Halli. The Arkavathy moves further on and where the Kumudvathy merges with is the second large reservoir built for Bangalore city’s water in 1934. This reservoir, conceived by Sir M. Visveshvaraiah, once supplied 135 million litres of water daily to Bangalore but not any more. Its catchment area is 1,453 sq. kms., and covers parts of Doddaballapur, Nelamangala, Devanahalli, Magadi and Bangalore north taluks

While the Hesarghatta has remained dry for several years now, the TG halli has rarely filled up in recent years, leaving Bangalore at the mercy of the Cauvery for water supply.

Thus our ancestors had once planned Arkavathy as a cascading system of holding water and fulfilling the needs of not only Bangalore but villages and towns enroute to Bangalore. If the tank overflowed or filled to the brim, water would naturally floe into the next tank. However, the cascade system-there are 1,084 tanks along the riverway till T.G. Halli-has been ruptured and none of the lakes lakes in the Arkavathy basin are full.

This shows our failure to arrive at a sustainable river and catchment management plan. If quarrying is the main threat to the free flow of Arkavathy, encroachment, apathy and wanton urbanization are sounding the deathknell for  Bangalore’s fragile water bodies.

The average annual rainfall in and around Bangalore city or urban area is estimates at a little over  66,400 hectares metres (ham) and of this the Geological Survey of India has calculated that 17,000 ham is runoff water. The ground water recharge is just 3290 ham and this means that over 71 per cent of rain water is lost due to various reasons, including evapotranspiration or ET which is the  the sum of evaporation and plant transpiration from the land surface to atmosphere.

Interpolate this aspect with the Cauvery water supply to Bangalore. The BWSSB is able to pump in annually 24,923 ham as against the demand of 48,600 ham. Besides, the city today has close to 3.5 lakhs borewells supplying 12,500 ham, leaving a shortage of over 12,000 ham.

The best way to meet or make up for this shortage is to harness the water potential in storm water drains. The storm water discharge is pegged at 17,040 ham and this is apart from the sewage flow of  26,316 ham. If all this water is treated, there is no reason for Bangalore to suffer any water shortage and this hold true even when the Sun shines brightly and Bangaloreans sweat it out in scorching summer.  
(This is the fourth in the series of posts on Urban flooding and Bangalore.) 

The first flooding of Bangalore

A sharp spell of rain is all that it takes for Bangalore to turn into a nightmare, leaving road flooded, drains overflowing, houses and apartments water logged and traffic piled up for hours on end.

In the previous post on urban flooding, we had spoken of  how the first recorded flooding of Bangalore took place more than a century ago.

Since then, little has changed. Every rain brings forth the same age old problems, the same assurances and of course the same result. The only thing that seems to have changed is the name of the civic body. It was Bangalore Municipality when it was started in the id 1900s. It then became the City Corporation of Bangalore and now the Bruhat Bangalore Mahanagara Palike (BBMP).

Though the BBMP has identified five main areas in the city as flood prone, there seems to be a clear lack of focus and commitment in taking remedial action.

The Ejipura-Koramangala area comprising also of National Games village, BTM Layout Ist and 2^nd Stages, parts of Bannerghatta road and Jayanagar-JP Nagar: Shankarappa Garden which embraces Magadi Road and surrounding areas: Brindavan Nagar and Mathikere areas and finally Ambedkar College that straddles across Airport Road area.

Apart from this, the BBMP has identified 134 low lying and flood prone areas. Such areas have been identified in each zone, including zones under Greater Bangalore like Byatarayanapura, Bommanahalli, Dasarahalli, Mahadevapura and Rajarajeshwarinagar.
BBMP says the east, west and south of Bangalore are more prone to flooding than the other parts.  It has identified Koramangala, Austin Town, Domlur and Jayamahal in the east zone; Rajkumar Road, RMV Layout, and Mahalakshmi Layout in west Zone;  Bhuvaneshwari Nagar, Maruthi Nagar, Bapuji Nagar and Tavarekere in the south zone as regular flood prone.

The east zone was found to be the most vulnerable to urban flooding with 108 areas, while the west zone had 31 such points.
Residential layouts situated within and in the periphery of these areas virtually turn into a sea of water and this is mainly because of the inability of the Koramangala valley to pump out excess rain and drain water.

The Koramangala valley has a fall of just thirty metres for a length of 13 kilometers that it traverses across the city.  Other natural valleys in the city such as Chellaghatta and Hebbal have a fall of 120 metres for 11 kms. Moreover, all the valleys are chocked with debris and encroached and heavily silted. These natural outflows needed to be fully cleared for smooth flow of rain and waste water away from Bangalore. This is the key to prevent flooding and water logging of drains and roads, inundation of low-lying areas and overflow of sewage onto to the streets.

The mean annual rainfall in Bangalore is about 880 millimetres (mm) spread over 60 rainy days in an year. The city has a network of a 180-km- long primary and secondary

storm-water drainage system. The network needs to be harnessed in its entirety and suitably remodelled  to take the monsoon load of the rains. Despite the remodeling taken up under the Jawaharlal Nehru scheme and spent hundreds of crores, nothing seems to have worked and a permanent solution continues to evade Bangalore.

Bangalore has a natural elevation of 920 metres and this means that the water can percolate on its own down the slopes. But why is this not happening. The answer is simple. Encroachment, illegal construction, blockage of storm water drains, breaching of tanks and lakes and deliberately blocking the natural flow of water.

Poor and often short sighted urban planning has resulted in Bangalore rapidly losing its green cover and water bodies, so much so that they have become the prime reason for almost all of the City’s ills. Bangalore is the only city among the big four metropolis of India-Mumbai, Kolkata, Delhi ad Chennai-not to be located in or near a water source. If Mumbai has the Arabian Sea, Kolkata the Ganges and Madras the Bay of Bengal, Delhi has the Yamuna but Bangalore has no such water body. The Cauvery, which supplies a major portion of the City’s water is 100 kilometres away.

Yet, Bangalore has seen a massive urban influx over the last five decades and there has been a 637 per cent increase in urban areas in Greater Bangalore area from 1973 to 2009 and it is still growing. The rise in built up area from 16 per cent in 2000 to around 24 in 2009 and almost 30 per cent today has seen a corresponding decrease in wet lands, breaching of lakes and tanks and decrease in green cover, leaving water with no natural course to flow off. This has been exacerbated by the presence of 542

slums with many of the lacking basic facilities in sanitation and hygine and straining the natural resources.

The wetlands in and around Bangalore decreased from 51 in 973 to just 17 now and even the water bodies have fallen sharply from 159 to 93. Besides, a staggering  66 per cent of lakes are sewage-fed, 14 per cent surrounded by slums and 72 per cent showed

loss of catchment areas. More alarmingly, catchment areas were used as dumping yards by all people and organizations ,including the civic agencies.

Between 2002 and 2009, water bodies decreased by almost 60 per cent and on an average 10,000 trees were cut every year. Thus, man interfered with the natural drainage system: destroying natural water channels, blocking natural flow of water, encroaching on water bodies and filling up drains and channels with debris. The  result: flooding and only one example of  how difficult it is to cope up with such events is enough to boggle one’s imagination. In August 2000,  torrential rains wrecked havoc on most parts of Bangalore and the BBMP had to pump out one crore litres of water from City Market area. This operation went on for three weeks. Where did this water go. To the drain and how. What the BBMP failed to ensure naturally, it had to do manually.

(This is the second part of a series of articles on urban flooding.)  

The sewage that floods our Anjeneya

It is one of the most famous temples of Bangalore and hundreds of devotees flock to it every day. The number goes up substantially on Sundays and holidays.

A few decades ago, anyone entering Bangalore from Mysore Road would first go to the temple and then enter the City. Politicians, businessmen and industrialists made it a point to seek the blessings of the deity and then start out on their ventures.

The temple became so famous that its fame spread far and wide. Alas, for the last few years, the temple has seen an annual occurrence that it could do without. Every time it rained, the storm water drain next to the temple overflowed and entered the temple premises.

The last several years have seen sewage water and garbage from the storm water drain flow into the temple and even enter the sanctum sanctorum. Several Chief Ministers right from the time of  Dharam Singh, H.D. Kumara Swamy and  B.S. Yeddyuruppa have come and gone but there seems no end to the problem.

It is only this time or rather this year when Bangalore received less than average rains that the Gali Anjeneya Temple on Mysore Road did not have any major problem of flooding.

The Gali Anjeneya Temple is one of the oldest temples in Bangalore and the Madhwa saint Vyasa Theertha of Vyasaraja Matha consecrated the idol of Hanuman more than five hundred years ago.

This was one of the 732 Hanuman temples that Vyasa Theertha consecrated all over India. While several hundred Anjeneyas were consecrated in Penukonda, Bangalore has several Vyasa Prathistha Hanuman temples.

The Hanuman Temple opposite the Minto Eye hospital, the Kote Anjeneya Temple, the Pranadevaru Temple at JP Nagar 6^th Block, and the beautiful and recently renovated temple of Hanuman near Yelahanka on the Yelahanka-Doddaballapur road are some of the other structures consecrated centuries ago by Vyasa Theertha.

The Gali Anjeneya Temple stands adjacent to the Vrishabhavathi river which today is nothing more than a storm water drain. With  almost all this drain network clogged by debris and sewage, the drainage water inundated the temple regularly and the Vrishabhavathi regularly breached the compound wall.

The filth and garbage had to be cleaned up from the temple regularly and even the priests had to lend a helping hand in this exercise.

Though several promise were made to rectify the issue, none of them seem to have gone to the root of the problem. It was only some time back that an elected representative from Bangalore took time off to look into the issue and suggest a simple solution.

One of the Members of the Legislative Council (MLC), Ashwathnarayanam decided to see why and how the waters from the storm water drain and the Vrishabhavathi enter the temple.

He went around the network of drains and canals that lead to the Vrishibhavati river and found that the flooding occurred due to a simple reason.

He found that one of the major canals from the Kempambhudhi lake, which is behind Kempegowda Nagar, was the reason for the frequent flooding.  The flood gates lake, which is upstream, were kept open to ensure that water did not stagnate in the lake.

So when rains came and water started collecting in the lake, it immediately moved out towards the Vrishabhavathi river. Thus, instead of holding excess rain water, the Kempembudhi Lake discharged more and more water, swelling the Vrishabhavathi river.

Already filled with garbage and debris, the river would overflow the embankment at Gali Anjeneya Temple and enter the structure.   
Another problem is that the Kempambudhi lake is connected by a network of drains from nearby Gavipuram Guttahalli, Chamarajpet, Shankarpuram, Basavanagudi and surrounding areas including Hanumanthanagar, Srinagar and other localities.

It is estimated that during the monsoon, these drains pump in at least 1850 cusecs of water  every day into the lake. And almost the entire quantity goes out as the crest gates of the tank is kept open.

The civic authorities have hot upon a solution to ensure that the temple is not flooded. They have decided to close the gate and let out water from the tank only after it fills up to a certain extent. This step would lessen the pressure on the Vrishabhvathi and also lead to steady discharge of water, avoiding flooding of  the temple.