[naveen.raju]

Originally Posted by LakeWalker

One thing I don't understand is why can't they make flyovers instead of these underpasses and giant-wall-roads leading up to them. Can someone who knows construction explain? For example, it works perfectly in a city like Bengaluru. Plenty of long flyovers here.

Officials in Kerala totally hate flyovers and you hardly get to see them here. Must appreciate Chennai on this as I was amazed to see the number of them being built during my college days. And the flyovers they built are useless (Aluva, Edapally, Vytilla).

And see their plan to decongest Edapally which is the second busiest junction here. Kochi is now known as the city of u turns.

[LakeWalker]

Originally Posted by naveen.raju

Officials in Kerala totally hate flyovers and you hardly get to see them here.

But NH66 is built by NHAI, right? I don't think any authority from Kerala has much say in it, apart from suggestions. I saw some reports where even locals (of some areas) are saying flyovers would've been a better idea since they don't really block their travel from one side to the other.

[binand]

Originally Posted by LakeWalker

But NH66 is built by NHAI, right? I don't think any authority from Kerala has much say in it, apart from suggestions.

NH 66 is built by NHAI, but on land acquired by the state government. Because of its largely urban nature, acquiring land in Kerala is always a problem - so the state prefers at-grade junctions that require less land over grade-separated interchanges. And NHAI obliges.

The state's first free-flowing interchange will be built near Pantheerankavu in Calicut, where the proposed greenfield Calicut-Palakkad highway will split off the existing NH 66 via a trumpet interchange.

[ringsoftime]

Originally Posted by LakeWalker

But NH66 is built by NHAI, right? I don't think any authority from Kerala has much say in it, apart from suggestions. I saw some reports where even locals (of some areas) are saying flyovers would've been a better idea since they don't really block their travel from one side to the other.

Originally Posted by binand

NH 66 is built by NHAI, but on land acquired by the state government. Because of its largely urban nature, acquiring land in Kerala is always a problem - so the state prefers at-grade junctions that require less land over grade-separated interchanges. And NHAI obliges.

The state's first free-flowing interchange will be built near Pantheerankavu in Calicut, where the proposed greenfield Calicut-Palakkad highway will split off the existing NH 66 via a trumpet interchange.

I think the land acquisitions didn't have any effect on the construction methods for the incident just happened. This was an MSE wall over paddy fields. The flyovers proposed by local are nor exactly flyovers, but viaducts. This stretch has a pretty long viaduct too, between Valanchery and Vattappara. While MSE wall were done nicely, you can see that retaining wall didn't fail and spill open wide, the soil under it moved. But if it was a viaduct, like the Valanchery Viaduct, the pillar would be piled on the base rock, providing a real strong foundation.
The images are pretty clear to me since I live close to Valanchery viaduct, which also has an MSE section, which is also constructed by directly dumping soil into the wet paddy fields. But they are much smaller and shorter than the wall in this section.

I am also afraid of the way NHAI has designed the edges with deep escavations, since the soil lining and concrete spraying is pretty strong on its own, the Drainage seems not.
The edges are not stepped and completely vertical, the drainages in service roads, can't completely get them out of the road and the soil beneath it. I really hope they are serviced and cleared before rains, each year.

This should be a wake up call at the national level to consider the climate and geological conditions much more diligently. Debarring the construction company which is just translating the NHAI designs is simply not enough.

[Innysta]

Originally Posted by naveen.raju

Officials in Kerala totally hate flyovers and you hardly get to see them here. Must appreciate Chennai on this as I was amazed to see the number of them being built during my college days. And the flyovers they built are useless (Aluva, Edapally, Vytilla).

And see their plan to decongest Edapally which is the second busiest junction here. Kochi is now known as the city of u turns.

Attachment 2759751

At Chennai, this kind of traffic arrangements have been done in last 6 months and few of it proved decongesting traffic (e.g. Kamakshi hospital signal junction where Tambaram-Velachery, Pallavaram-Thoraipakkam intersect). In other places, it just moved the traffic from one place to another added with the risk of vehicles taking U-turn and move extreme left, causing accidents. Riders new to the city get into the right lane and get choked with U-turn vehicles, realizing at last minute and swerving to left or folks in left most lane swerving to right to make U-turn are the scenes happening here

Recent development is the traffic changes done in Anna University service road causing pile up of traffic near IIT in Madhya Kailash-Anna University direction, adding 15 min to cross a 500m