Letter to Hon'ble LG _new bridge planned over river Yamuna _ - 4.7 ...

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Sir, it is also important that in the interest of the safety of the city downstream of Wazirabad, the integrity of the river and its water spread upstream of Wazirabad is not allowed to be compromised since in the eventuality of a massive release of say 9-10 lakh cusec at Hathnikund barrage (very much in the realm of possibility in the light of more than 8 lakh cusec seen in June 2013), which would mean more than 5 lakh cusec water reaching the city it may be necessary for the safety of the city to open some embankments to permit spread of water in farms and lands beyond the embankments in zone P II. Thus compromising of the integrity of the river system through raising of any structure including a bridge in north Delhi (Zone P II) is risky and inadvisable. Now in an unlikely scenario, where expert studies do necessitate a bridge over the river Yamuna upstream of Wazirabad in Delhi, then such a bridge may only be a long (no less than 5 km between embankments as has been held by the Yamuna Standing Committee way back in 1979) and a true bridge over pillars all along its length (with no guide bund in between to channelise the river in any manner) so that the bridge does not inhibit the flow and spread of flood waters in any manner. Unfortunately all the bridges presently in the city over the river are with the sole exception of under construction DMRC bridge downstream of HNZ bridge, are 'pseudo bridges' (please peruse our enclosed report on it) where they have on one hand channelised the river and on the other created avoidable cross embankments in the river in form of raised roads. Such poorly planned bridges are not good for the river as well as for themselves during very high flows. Here allow us to mention that both the bridges on river Yamuna at Kalanour (Yamunanagar) and at Mawi (Panipat- Kairana) faced trouble and closure over extended periods in 2010 and 2013 respectively due to design faults, where cautionary additional spans could have avoided the damage and trouble faced both by the bridges and the people using it. Sir, we hope that your goodself shall see merit in our submission and accordingly caution the concerned authorities. With warm regards, Manoj Misra Convener CC: Smt Sheila Dixit, Hon'ble Chief Minister of Delhi – For your kind information and necessary action please. Chairman, Yamuna Standing Committee, Central Water Commission, Sewa Bhawan, R.K. Puram, New Delhi – For your kind information and necessary action please. Chairman, Delhi Urban Arts Commission, India Habitat Centre, Lodhi Road, New Delhi – 110 003 – For your kind information and necessary action please. Vice Chairman, Delhi Development Authority – For your kind information and necessary action please.
Introduction WHY ‘PSEUDO’ BRIDGES ARE UNDESIRABLE OVER THE RIVER YAMUNA? Manoj Misra* A bridge over a river is a man made structure to enable safe and easy conveyance of man and material across a river. Thus the purpose of a bridge is to convey. It is not to obstruct the river in its natural course and functions. Most importantly, it must not restrict by design the unhindered spread and flow downstream of the flood waters. This is the reason why a ‘true’ bridge would span over the entire known flood plain of a river from it’s one bank to the other. It is also the reason why a smart engineer would choose the narrowest portion of a river to build a bridge over it and plan a road or railway’s alignment in the manner. But now a days especially in an urban setting with roads and railways (Metro in particular) criss-crossing every part of a city, such smart choices of sites for bridges get remoter by the day. Situation of river in urban Delhi It is admitted that there can certainly be bridges built over just the lean season channel of a river provided the approach road to them is no higher than the natural level of the river bed, so that these in times of floods do not act as cross embankments to the flow downstream of a river in spate. And there were such examples of pontoon bridges built annually at Majnu Ka Tila, Gita colony, Bhairon Road and Sarai Kale Khan till recent times, but none of these ever proved to be a hindrance to the flow of flood waters in the city since their approach roads followed the natural contour and level of the river bed. But the unscientific and hence unfortunate state of the bridges over the river Yamuna in the 22 km stretch of the river in the city is that but for the British built bridge (old Yamuna Bridge joining Salimgarh Fort to Shahdara area) none of the other existing 7 bridges (ISBT, DMRC Shastri Park, Gita Colony, DMRC Yamuna Bank, New Railway Bridge, HNZ Bridge, DND flyway) or under construction Signature Bridge is a ‘true’ bridge. They are all cross embankments raised on the river, with the bridge portion covering just the rivers’ lean season channel of 500 – 800 m span against its actual length of 2.5 – 3 km. This it appears has been done on the lines of the 3 barrages standing on the river in the city, namely the ones at Wazirabad, ITO and at Okhla. But while a ‘barrage’ is meant to hold and divert water from a river, a ‘bridge’ is not. So when cross embankments in the river get built in the name of bridges (pseudo) then they too begin to act like barrages and lead to the following objectionable and undesirable results? Channelisation of the river It may be noted that the river Yamuna has a natural tendency to meander within its flood plains. In the 22 km stretch of the river in Delhi it has a pronounced meander whereby the river channel shifts repeatedly from west to east and to west again.
Page 1: 4 July 2013 YJA/CORRES/7/13 Sri Tej
Page 5 and 6: Park locality of East Delhi, where
Page 7 and 8: SPREAD OF WATER UPSTREAM OF WAZIRAB

Letter to Hon'ble LG _new bridge planned over river Yamuna _ - 4.7 ...

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