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Koramangala 4th block flood mitigation plan

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A few weeks back, there was an announcement of the commencement of work on the subject plan, with a pooja, presided over by the BTM layout (under which Assembly constituency, the area falls) MLA, Sri Ramalinga Reddy.
The announcement talked about laying of pipelines along the 80 ft road (Google terms it "Srinivagilu main road"), in the vicinity of Sony-World junction and Maharaja junction, and, with the area already badly congested, there was anxiety among residents to understand what the whole proposal was, as also how it's going to affect their overall mobility.
I requested Mr Srinivas Reddy, EE, BBMP, if he could make a presentation to 4th block (which includes S T Bed layout) residents on the proposal, or at least provide the drawings. But, he seemed to suggest he was busy. Subsequently, I spoke to Mr Govardhan Reddy, the Block Congress convener, and it is based on my understanding of what he had stated that I have put together this report.
The thin blue line indicates the under-ground pipeline originating somewhere near the Sony-World junction and ending at the "wet-well" somewhere near Wipro (Kamal bakery) junction, into which flood-water accumulating along the stretch will enter through gratings on the surface. From the wet-well, the water is supposed to be taken to Bellandur lake through 6ft dia pipes (seen in picture below, and indicated in deep blue colour, in the picture above).
The crossing of the Storm-water drain (SWD), near "Seva-in-Action", is suppsed to be through a 'siphon' arrangement as depicted in the picture below:
Now, there is already a sewage line below the SWD, which if you assume as 4ft dia (b), 'c' is 6ft, and if the bed of the SWD is 12ft from the ground level, then the excavation has to be to a level of minimum 22 ft from the ground level. 
From there, it flows through along points marked PIC3, PIC2, and then along the SWD from PIC4, and empties into Bellandur lake at PIC1 (beyond the SWD wall seen in the picture). The crimson arrows indicate the direction in which the picture were taken.
The whole idea of publishing this report is to help the community understand what is in store, make their own assessments (many are engineers, some specialised in Hydrology, too), and engage with the powers that be to make correctives, if required.
Well, for even for an Electrical Engineer like me, following questions arise:
1) Water is flowing into the Bellandur lake in the SWD. So, the natural gradient is available. But, is it good enough for high flood discharge? If not, is there a fear of water backing up, and causing bigger damage?
2) The siphon arrangement appears very dicey. There is every chance of muck collecting at the bends and blocking the flow. How is it proposed to be cleaned? And, is it going to be gravity flow through it from the wet-well, or is it going to be pumped?
3) The flood-water channelisation through road-side gratings into under-ground pipeline along the length of the 80 ft road also appears a tricky job.
The bigger question that arises is, when undertaking such massive jobs which have huge impact on the life of the community, shouldn't there have been wider citizen consultations before starting work on it? The entire area is cluttered with those massive pipes, which means huge sums have already been spent.
Well, all in all, the city governance certainly calls for total re-structuring.
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