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The second route must strictly be decided based on the financial merit in long run especially Rate of return and economic rate of return instead of rationing it or deciding on political considerations.This is because the stakes are very high, i.e. the project shall cost upward of Rs 200 Crores per k.m. Any wrong decision may badly damage IR economy or dent Indian economy.
Going for Delhi-Mum which is one of the crack options, the additional additional advantages are
(1) it shall entail construction for only AHM-DEL section only which...
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is 900km (the MUM-AHM shall be already existing) and reduce the costing to minimum. say about 1.8 lac crore Rs
(2) It will incorporate following sections which had been identified earlier for HST (1) MUM-AHM, (2) MUM-DEL, (2) DEL-JP
(3) same maintenance workshop constructed for MUM-AHM project shall be in a position to cater to AHM-DElhi project as well,so cost shall be saved.
(4) Mum-Delhi air traffic is extremely high and is sixth highest between any 2 pair of cities in world! These passengers are the potential traffic for bullet trains which are extremely high for this route, much higher than any other pair of options considered. So maximum clientele for bullet train exists in this route.
Top 10air traffic routes in India which shall be a main source of paxs to bullet trains are are
Data of 6months from oct'15 to mar'16. (Note the traffic has increased about 22% this yr over previous year.)
1-Mumbai-Delhi -- 31.4 lacs
2-Delhi-Bangalore ---17.48 lacs
3-Mumbai- Bangalore -16.38 lacs
4-Mumbai Goa-- 11.77 lacs
5-Mumbai-Ahmedabad-- 11.07 lacs
6-Kolkata Delhi --10.77 lacs
7-Delhi-Hyderabad-10.53 lacs
8-Mumbai-Chennai--9.97 lacs
9-Delhi-Chennai-9.89 lacs
10-Mum-Hyderabad- 9.39 lacs
It is interesting to note that 6 out of the 10 top air traffic routes involve Mumbai, where as only 5 routes involve Delhi. Where as IR runs at least 3 times the fully ac premium trains from Delhi as compared to Mumbai!!! How much the political capital get pampered by IR where air traffic is true reflection of Market demand !!!