Know
your Adyar River ? People asking why there is so much water flow in
Adyar River, without much water in Chembarabakkam Dam, why is so much
water let out from Chembarabakkam Dam - To clarify there is no water
released from Chembarabakkam Dam.
Our people rarely know their local rivers, i am not finding fault, because its not taught in their school education. All we know is Ganga, Cauvery or Krishna river and other major rivers in India. So kids / adults these days know about the large rivers, but not the local rivers ecosytem which flow in their backyard which might come handy during disasters. When water flow is high in Adyar River, people in Koyembedu fear that water will come into their locality without knowing that they are near Cooum River.
Since 2015, i wanted to put up this one. But it would have been controversial at that time and affected people might have not thought rationally, having visited all these drains, i feel its is right time to put a post in Adyar River system exp.
1. Why there is huge flow of water in Adyar River today in December 2019 with Chemba being just 25% full ?
----------------------------------
Many believe that Chembarabakkam is the starting point of the Adyar River, as you can see, the Adyar River starts from Adhanur Tank near Nandhivaram-Guduvanchery bet. There are 6 waterways + the original river which starts well beyond the connecting point of before Chembarabakkam Surplus water joins Adayar River ear Thiruneermalai. These lakes in Mannivakkam, Somangalam, Orathur-Arambakkam (where Chennai's 6th dam is proposed ) are mostly full after widespread rains this monsoon. All these flows wont go to Chembarabakkam Dam as its topography is different (see image enclosed). Chembarabakkam dam as on date has 1200 mcft of water against 3600 mcft of full capacity. No water has been released from Chembarabakkam Dam against claims of few news channel portraying that water is being wasted. It is the flow from the other waterways of Adyar River and the original river catchment too. Adyar river is not perennial river and its only seasonal, rivers are meant to flow right, let the river have some flow atleast to clean the pollutants accumulated over the past 4 years. (Last time in 2015 floods, it was self cleaned).
2. Why Adyar River floods compared to other basin ? - A funnel type basin with huge mouth in upstream and tube in downstream.
------------------------------
Please refer the Adyar Basin image. Its area is 850 Sq.km of which 80% of which are in upstream having a funnel type and the down stream when it enters city it acts only like a tube. So assume on December 2nd morning 2015, in Adyar basin, the following are the rainfall reported are in 24 hrs. (Tambaram - 494 mm, Chembarbakkam - 475 mm, Kattankolathur - 445 mm, Katupakkam - 425 mm). Based on radar accumulation, the places in Mudichur, Mannivakkaam, Somangalam, Orathur, Nallur which all are catchment of Adyar River should have got the peak spell of atleast 600 mm on December 1st morning to 2nd morning. The funnel is filled to brim with highly saturated soil as it was the 7th or 8th big spell of that monsoon. Chembarabakkam Dam received huge inflows and water was being released, maximum u can release is 35000 cusecs. In 2.00 pm update on December 1st update in my page, i had put that Chembarabakkam lake water is being released. Rain stops next morning. The water takes time to generate run-off and slowly starts to accumulate towards the tube of the funnel. Further, the cup in the upstream catchment is in higher topography and the tube part of the river in downstream is in lower topography with flat terrain. So the water from upstream comes down at higher speed to the city because of the terrain and once in the city the speed reduces and moves at slower pace. This causes stagnation and backwater effect in the City. Many people in the upstream area who have encroached in lake bed cut opened the lakes fearing their house being flooded with increasing water. Adyar River can handle 50000 cusecs with ease. At Jafferkhanpet the flow in Adyar was over 1.1 lakh cusecs. Banks were breached with encroached river, the carrying capacity was reduced. We are the only city in the world who has Airport runway over a river. It was not only the Chemba water more than 70% of the water was coming from other areas. A comparison of 1976, 2005 and 2015 floods show where ever the river meandered inside the city they broke the bands. So when ever there is a flow, do understand its not always from Chemba, Adyar River has many other connecting drains and the river itself does not start from Chemba, instead it is from Aadhanur near Nandhivaram Guduvancherry. I know many affected and the psychological effects will be there. They too need to know why there was so much water flow in Adyar in 2015.
The above views are strictly personal. Hopefully, you got your answers with facts !!! Dont blindly believe what is said in TV. The Adyar river ecosystem in upstream are beautiful ones. Learn about your ecosystem and protect them !!!!
Chennai Lakes crosses 5 tmc mark and will keep rising
------------------
We have good water this year. Storage in 4 Chennai water supply lakes have crossed 5 tmc and with Veeranam it is 6 tmc. With Krishna water stepping up we might see the 4 lakes water level crossing 6 tmc in next 15 days and with Veeranam we will be over 7 tmc. Thats a storage level i will take it any year though i personally expected the levels to touch 10 tmc. Tricky November let us down. Had that bulbul and easterly wave on November 14-15 given rains, we would all be discussing floods right now. Everything for good !!! 2020 with improved ground water and good lake levels will be water scarcity free !!!.
Our people rarely know their local rivers, i am not finding fault, because its not taught in their school education. All we know is Ganga, Cauvery or Krishna river and other major rivers in India. So kids / adults these days know about the large rivers, but not the local rivers ecosytem which flow in their backyard which might come handy during disasters. When water flow is high in Adyar River, people in Koyembedu fear that water will come into their locality without knowing that they are near Cooum River.
Since 2015, i wanted to put up this one. But it would have been controversial at that time and affected people might have not thought rationally, having visited all these drains, i feel its is right time to put a post in Adyar River system exp.
1. Why there is huge flow of water in Adyar River today in December 2019 with Chemba being just 25% full ?
----------------------------------
Many believe that Chembarabakkam is the starting point of the Adyar River, as you can see, the Adyar River starts from Adhanur Tank near Nandhivaram-Guduvanchery bet. There are 6 waterways + the original river which starts well beyond the connecting point of before Chembarabakkam Surplus water joins Adayar River ear Thiruneermalai. These lakes in Mannivakkam, Somangalam, Orathur-Arambakkam (where Chennai's 6th dam is proposed ) are mostly full after widespread rains this monsoon. All these flows wont go to Chembarabakkam Dam as its topography is different (see image enclosed). Chembarabakkam dam as on date has 1200 mcft of water against 3600 mcft of full capacity. No water has been released from Chembarabakkam Dam against claims of few news channel portraying that water is being wasted. It is the flow from the other waterways of Adyar River and the original river catchment too. Adyar river is not perennial river and its only seasonal, rivers are meant to flow right, let the river have some flow atleast to clean the pollutants accumulated over the past 4 years. (Last time in 2015 floods, it was self cleaned).
2. Why Adyar River floods compared to other basin ? - A funnel type basin with huge mouth in upstream and tube in downstream.
------------------------------
Please refer the Adyar Basin image. Its area is 850 Sq.km of which 80% of which are in upstream having a funnel type and the down stream when it enters city it acts only like a tube. So assume on December 2nd morning 2015, in Adyar basin, the following are the rainfall reported are in 24 hrs. (Tambaram - 494 mm, Chembarbakkam - 475 mm, Kattankolathur - 445 mm, Katupakkam - 425 mm). Based on radar accumulation, the places in Mudichur, Mannivakkaam, Somangalam, Orathur, Nallur which all are catchment of Adyar River should have got the peak spell of atleast 600 mm on December 1st morning to 2nd morning. The funnel is filled to brim with highly saturated soil as it was the 7th or 8th big spell of that monsoon. Chembarabakkam Dam received huge inflows and water was being released, maximum u can release is 35000 cusecs. In 2.00 pm update on December 1st update in my page, i had put that Chembarabakkam lake water is being released. Rain stops next morning. The water takes time to generate run-off and slowly starts to accumulate towards the tube of the funnel. Further, the cup in the upstream catchment is in higher topography and the tube part of the river in downstream is in lower topography with flat terrain. So the water from upstream comes down at higher speed to the city because of the terrain and once in the city the speed reduces and moves at slower pace. This causes stagnation and backwater effect in the City. Many people in the upstream area who have encroached in lake bed cut opened the lakes fearing their house being flooded with increasing water. Adyar River can handle 50000 cusecs with ease. At Jafferkhanpet the flow in Adyar was over 1.1 lakh cusecs. Banks were breached with encroached river, the carrying capacity was reduced. We are the only city in the world who has Airport runway over a river. It was not only the Chemba water more than 70% of the water was coming from other areas. A comparison of 1976, 2005 and 2015 floods show where ever the river meandered inside the city they broke the bands. So when ever there is a flow, do understand its not always from Chemba, Adyar River has many other connecting drains and the river itself does not start from Chemba, instead it is from Aadhanur near Nandhivaram Guduvancherry. I know many affected and the psychological effects will be there. They too need to know why there was so much water flow in Adyar in 2015.
The above views are strictly personal. Hopefully, you got your answers with facts !!! Dont blindly believe what is said in TV. The Adyar river ecosystem in upstream are beautiful ones. Learn about your ecosystem and protect them !!!!
Chennai Lakes crosses 5 tmc mark and will keep rising
------------------
We have good water this year. Storage in 4 Chennai water supply lakes have crossed 5 tmc and with Veeranam it is 6 tmc. With Krishna water stepping up we might see the 4 lakes water level crossing 6 tmc in next 15 days and with Veeranam we will be over 7 tmc. Thats a storage level i will take it any year though i personally expected the levels to touch 10 tmc. Tricky November let us down. Had that bulbul and easterly wave on November 14-15 given rains, we would all be discussing floods right now. Everything for good !!! 2020 with improved ground water and good lake levels will be water scarcity free !!!.
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