STORM WATER DRAINAGE PROJECT IN CHENNAI NEED TO BE REVISITED
For over three years now, storm water drainage project has been talk of the town in Chennai, when it was said that the project would cover 559 roads , covering a distance of 1033 kilometres which cost around Rs. 4070 crore.
Ever since the scheme was announced and the design was publicised , there have been considerable skepticism expressed by experts about the success of the scheme for various reasons. Experts with hands on experience in the related area wondered whether the various technological options and alternate ways for laying the storm water drain have been carefully examined, considering the local conditions in Chennai such as rain fall intensity , periodicity of flooding, extent of flooding, the existing road construction and traffic intensity and density of population in the local area. On the other hand, the experts pointed out that the same design have been adopted for the entire city, not considering the local conditions. For example, it was pointed out that in Besant Nagar and nearby area which are near the seashore , the soil conditions are loose and the flood water would quickly percolate into the soil , where such projects are not necessary.
The design of the scheme was also questioned since storm water drain was constructed in such a way that its top level has been around one foot above the road level in most places . If there would be rainfall, the rain water would get inside the house as the top portion of the drainage structure is above the floor level of the house. As a result,, in several places, residents have to spend considerable amount to raise the floor level in the compound to the top level of the drainage structure. I have spent around rupees one lakh for rising the floor in my house.
As part of the project, digging of the road was done to around 3 to 4 feet deep and width of around 2 to 3 feet. The drains were constructed using steel reinforced cement concrete with two walls on either side with provisions for manhole, chute etc. This has been done in front of several houses leaving little space between the gate of the house and that of the drainage structure.
There was also criticism about the lack of supervision and the gradient not being maintained properly in several places. to enable free flow of water.
The government reacted to all these criticisms by simply stating that the design has been approved by professors from IIT Madras.
In November 2022, the government said that 95% of the work has been completed and assured that flooding would not be a problem in Chennai anymore.
In any case , it is said that “proof of the pudding is in the eating", which mean that one can only judge the quality of something by trying it or experiencing it.
After the year 2022, there have been number of storms and heavy rains in Chennai and it has been seen that most part of Chennai has been as much flooded as the pre storm water drainage project era. Obviously, this implies that entire storm water drain project designed and implemented has to be revisited to learn the right lessons for the future.
Careful evaluation of the various factors are necessary, so that alternate methods can be thought of for future projects that would be least expensive way for building storm water drain, that can be finished in quick time without causing inconvenience and problems for the residents.
It appears that the authorities have chosen the most expensive and time consuming way of laying storm water drain, by digging deep into the soil and using steel reinforced concrete, chute pipe , manhole cover, inlet chambers, retailing wall etc.
Experts say that in a crowded city like Chennai, drainage pipes could have been used for draining the storm water and the pipes can be laid under the ground, instead of the pattern of the work carried out . There are PVC and HDPE pipe options, both of which have become extremely popular in drainage applications in recent years all over the world, thanks to their resistance to collapse and chemical corrosion, flexibility and durability.
While PVC pipes are quite easy to install, HDPE pipe is generally the better choice for high pressure systems. Suitable provisions can be made in the pipes for connection, inspection, cleaning etc. from time to time, as required. Use of such HDPE pipe system for storm water drain would have cost much less , job could have been done quicker and inconvenience to the residents could have been reduced significantly and free flow of water in the pipe would be much better.
N.S.Venkataraman
Nandini Voice For The Deprived
Chennai more
Ever since the scheme was announced and the design was publicised , there have been considerable skepticism expressed by experts about the success of the scheme for various reasons. Experts with hands on experience in the related area wondered whether the various technological options and alternate ways for laying the storm water drain have been carefully examined, considering the local conditions in Chennai such as rain fall intensity , periodicity of flooding, extent of flooding, the existing road construction and traffic intensity and density of population in the local area. On the other hand, the experts pointed out that the same design have been adopted for the entire city, not considering the local conditions. For example, it was pointed out that in Besant Nagar and nearby area which are near the seashore , the soil conditions are loose and the flood water would quickly percolate into the soil , where such projects are not necessary.
The design of the scheme was also questioned since storm water drain was constructed in such a way that its top level has been around one foot above the road level in most places . If there would be rainfall, the rain water would get inside the house as the top portion of the drainage structure is above the floor level of the house. As a result,, in several places, residents have to spend considerable amount to raise the floor level in the compound to the top level of the drainage structure. I have spent around rupees one lakh for rising the floor in my house.
As part of the project, digging of the road was done to around 3 to 4 feet deep and width of around 2 to 3 feet. The drains were constructed using steel reinforced cement concrete with two walls on either side with provisions for manhole, chute etc. This has been done in front of several houses leaving little space between the gate of the house and that of the drainage structure.
There was also criticism about the lack of supervision and the gradient not being maintained properly in several places. to enable free flow of water.
The government reacted to all these criticisms by simply stating that the design has been approved by professors from IIT Madras.
In November 2022, the government said that 95% of the work has been completed and assured that flooding would not be a problem in Chennai anymore.
In any case , it is said that “proof of the pudding is in the eating", which mean that one can only judge the quality of something by trying it or experiencing it.
After the year 2022, there have been number of storms and heavy rains in Chennai and it has been seen that most part of Chennai has been as much flooded as the pre storm water drainage project era. Obviously, this implies that entire storm water drain project designed and implemented has to be revisited to learn the right lessons for the future.
Careful evaluation of the various factors are necessary, so that alternate methods can be thought of for future projects that would be least expensive way for building storm water drain, that can be finished in quick time without causing inconvenience and problems for the residents.
It appears that the authorities have chosen the most expensive and time consuming way of laying storm water drain, by digging deep into the soil and using steel reinforced concrete, chute pipe , manhole cover, inlet chambers, retailing wall etc.
Experts say that in a crowded city like Chennai, drainage pipes could have been used for draining the storm water and the pipes can be laid under the ground, instead of the pattern of the work carried out . There are PVC and HDPE pipe options, both of which have become extremely popular in drainage applications in recent years all over the world, thanks to their resistance to collapse and chemical corrosion, flexibility and durability.
While PVC pipes are quite easy to install, HDPE pipe is generally the better choice for high pressure systems. Suitable provisions can be made in the pipes for connection, inspection, cleaning etc. from time to time, as required. Use of such HDPE pipe system for storm water drain would have cost much less , job could have been done quicker and inconvenience to the residents could have been reduced significantly and free flow of water in the pipe would be much better.
N.S.Venkataraman
Nandini Voice For The Deprived
Chennai more
Viewed by 525
Yes, storm water drains have been constructed for excess water to flow. But soon after construction, the inlets are plugged with dust, leaves from trees, plastic bags. Who will keep the inlets free of these accumulations?. This was not thought of. Alternative methods of water drain should have been considered. The cemented storm water drain itself is a bad idea. more
Feb 07
PROOF OF THE PUDDING IS IN THE EATING... IT IS THE STORY OF THE CROCODILE IN THE COOUM!!! more
Jan 28
Yes , it is true we have been living in East Avenue, Korattur on the MTH road side which was 3 feet above the road level in 2010. Now our TNHB houses are 2 feet below the road level and our SIDCO industrial estate also gone below by two feet. water had entered in to houses and SIDCO more than 3 feet from the floor level. we had this problem during our stay of 40 years in the flat. It is the first drain constructed in our area where the location of cable and water canal was wrongly swapped by the stupids engineers. when this comedy will be set right more
Jan 27
