How effective are SWDs in city

By Santhosh Mathevan Published on Nov 06, 2017 02:45 PM IST

Chennai: After the December floods in 2015, the city Corporation took up lot of precautionary measures to avoid floods in the future.

This includes construction of storm water drains, desilting of lakes and tanks, and digging up new linking canals that took place in the city in last one year in order to manage the excess water flow during heavy rains.

So, how was the process taken up and how efficient was that in terms of benefits?

News Today took up a ground zero study.

Unfortunately, despite all these infra-boosts, the city still seems to be in the alert zone. With not even a week long of heavy rains, Chennai, already has started to witness water stagnation in most of the residential and industrial areas. Residents from most of the areas have started to raise complaints on the same and also express fear for occurrence of another flood.

"During the construction of Metro Rail in our area, there occurred an overlap with the drainage line and the foundation of the metro rail pillars. With that, they closed the foundation as such due to which blockages were formed in the drainage lines. So, whenever it rains,  water stagnates immediately," said Arunkumar Navaneethan, a resident of Ashok Nagar.

On a similar note, Jeyakannan Yogarajan from Mugalivakkam locality in Porur told, 'The storm water drain project is not happening properly in our locality and so, we still face the same issue even this year. All barren lands and empty lands get water stagnation and water is running on the road.

From the versions of Corporation sources and officials, it was found that, the SWD project would take some more time to give out its full fledge use.

According to sources form the Greater Chennai Corporation, it has a plan of connecting 900 kilometers of road with storm water drains. This drain network along with Cooum, Adyar, Buckingham canal, and 16 minor canals form the rain water drainage network in the city.

Sources said that, in order to find out a comprehensive solution to relieve water stagnation problem, Greater Chennai Corporation joining hands with Public Works Department has appointed a consultant and prepared a detailed project report in the beginning of 2016.

According to this project, the city is divided into 12 water sheds and into three basins and propose comprehensive system of drainage network.

In this project, Greater Chennai Corporation will take up improvements of 16 canals, construction of new storm water drains to a length of 307km and Re- construction of storm water drains to a length of 149 km will be taken up under Micro Drainage system.

A top official from the city corporation said that the funding pattern is such that the Central Government takes a share of 35 per cent, State Government with 15 per cent  and the Urban Local Body shares 50 per cent. There was not any problem in getting the funds too, according to the official. The work will be carried out in three phases.

'The overall time estimated to complete all the three phases was three years, however only one phase is completed till now.. We still need a year and half to complete the entire project', the official said and further added that, after implementation of this scheme, water stagnation will be relieved considerably in the city.

However, comparing to the 2015 rains, this year, the stagnation of water has come down in terms of its severity. Areas like T Nagar, Velacheri, Vyasarpadi and Kotturpuram did not face much of a stagnation when compared to the 2015 tragedy.

"This year, we have been witnessing stagnation of water only during the time of rain and it gets drained soon after the showers stop," says Vinoth Sampath, a resident of  Mambalam who said that the storm water drains have been effective to some extent.

Like wise, residents of Velacheri too are happy that their neighbourhood survived the rains. "Surprisingly, this year, we did not face a huge water catchment issue this year. Since Velacheri's storm water drains are deeper than the usual SWD, and it connects with the Palliakaranai Marsh, we have a proper water transmission system by preventing it from stagnation," said S Kumarraja, from Annai Indira Nagar, Velacheri.

Project status
Adyar and Coovum:

In first phase, detailed project estimates were  prepared for Rs.1101.43 crore. SWD construction to a  length of 326 km has been taken up, at present SWD works to a length of 220 km have been completed. The works are completed in zonal areas of Ambattur, Valasaravakkam and Alandur.


As far as the integrated storm water drain project for Kovalam Basin is concerned, the German Development Bank (KfW) has been identified as the funding agency for implementation of the project at a cost of Rs.1243.45 crore to a length of 360 km.


While for Kosasthalaiyar Basin, the Japan International Co-operation Agency (JICA) has been identified as the funding agency to implement this project at a project cost of Rs.1881.66 crore to a length of 429 km.