Every year the monsoon brings relief from the scorching heat in the city but heats up the debate on the drainage system which soon converts into a blame game among civic agencies and fades away with the receding monsoon, without having found any solution to the problem of waterlogging in the national capital. The cycle of this debate, blame game and also woes of waterlogging, flooding and resultant traffic chaos on the streets has become part of life in Delhi. Will the capital, which aspires to become Paris, ever get a fool-proof system and if yes, how?'The problems of waterlogging and flooding in Delhi are multi-faceted and need a multi-pronged approach,' says professor P K Sarkar of the School of Planning and Architecture (SPA). 'There must be an independent agency to coordinate and monitor the drainage system in the city. There is a need to check and verify the claims of de-silting and maintenance work made by various civic agencies,' he adds.
Rainwater flows through small drains that are connected to bigger drains, which in turn connect to 61 grand drains managed by the Irrigation and Flood Department of the Delhi government. Water from these grand drains finally flows into the Yamuna. Between the small drains and the river, there are 10 major managing agencies, the three municipal corporations in Delhi (North DMC, South DMC and East DMC), New Delhi Municipal Council (NDMC), Delhi Development Authority (DDA), Central Public Works Department (CPWD), Railways, Delhi Cantonment Board (DCB), Delhi Sate Industrial and Infrastructural Development Corporation (DSIIDC) and Delhi Metro Rail Corporation (DMRC). These agencies manage the overall sanitation and drainage systems in the areas under their jurisdiction. DDA has the full responsibility of providing civic amenities in the newly-constructed townships and colonies which have not been handed over to the municipal corporations. Approximately, half of Dwarka and the new sectors in the Rohini area are under the DDA. Besides, the Delhi Jal Board (DJB), which manages the sewage system in the city and water supply lines, also has a crucial role to play. The larger drains in the city are managed by the Public Works Department (PWD) and DSIIDC.'There is a need to make people aware of garbage management. Presently, everything from polythene to debris from under-construction buildings are dumped into the drains,' argues Sarkar, who is part of the H-8 Committee of the Indian Road Congress, which is drafting a plan for a unified drainage and transportation system in Indian metropolitan cities. He further adds that large roads, bridges and flyovers are great sources of water harvesting which can minimise the problems of waterlogging in the city.But these are not and cannot be the only solutions.
'The drainage system in Delhi is between 40 to 100 years old and needs to be completely revanmped. The carrying capacity of drains at places is not sufficient, as the city has changed a lot in terms of population and concretisation in these years,' said professor A K Gosain of the Indian Institute of Technology (IIT), Delhi. Gosain is handling the project 'Drainage Master Plan for NCR', sponsored by the Delhi government. 'The two major problems with the drainage system in Delhi are inadequate sizes of drains and choking of drains,' added Gosain. His study is still at a nascent stage and he is yet to receive data from various stakeholders. 'We have written to various agencies to provide invert level and cross section of drains to study their carrying capacity but have been waiting for the inputs for the past one year. Once the data is received, it will take six months to finalise the project,' added Gosain.There is another problem. 'When the water level of the Yamuna reaches 204.22 metres, the water starts flowing back in to major drains and at 205.44 metres its starts flowing back into almost all the 61 drains managed by the flood department,' said a senior officer of the Delhi government.
The absence of proper sewage systems in the unauthorised colonies and jhuggi-jhopri (JJ) clusters is another problem. According to a rough estimate, over 40 per cent unauthorised colonies and almost all the JJ clusters don't have proper sewage systems. Also, residents in these colonies and squatters dump garbage in the drains passing through these areas. 'The drains here overflow through the year and even a mild shower is enough to cause waterlogging,' said a senior PWD officer.