Pedestrian Subway - Change In Design

IDS - Good example for locations where there is ample space, also assists wheel-chairs, prams, & hand carts !

At most locations, we seem to have space constraints. I think the walk distance also increases with this design, is'nt it ?

IDS - Perhaps both reasons !

Re. The later sketch for design of Ped Subway, the subway is shown 'sunk' by 3 ft below ground, thus, the road has to rise up by 5' (not 4' & 4' as previously mentioned). Thus, the calculations would correspondingly differ, but the point remains valid, viz. make it much easier for the pedestrian & not for motorized vehicles.

IDS & NJ - You are correct about zebra crossings being the ideal solution as they cause no inconvenience to pedestrians - I would also have preferred those to anything else, but unfortunately, they involve safety hazards & monitoring.

Considering that pedestrian deaths in relation to other road accidents are the highest in the city, I feel that grade separation is called for to provide safer means & this was one option I felt might work, especially after seeing similar designs in China & also in Mumbai.

I would prefer you not ridicule it since others have found it suitable & I also do not see how or why these are being argued as unsuitable when so many similar magic boxes are being put up for vehicle movements involving even higher rises & falls contours on streets. Are pedestrians not deserving of similar considerations ? If at all, the design that I have mentioned reduces the rise & fall & over a smaller distance whilst allowing the pedestrians to descend & ascend fewer steps than those that maintain at-grade streets (like the ones being installed by BBMP).

I request other/s to comment about this.

NJ - I agree with Srivathsa & think that you are exaggerating.

In Mumbai, along the Western Express, Eastern express highways & also along the Andheri-Ghatkopar road, there are a few locations (cant remember exact areas) where the road rises up to allow for pedestrian subways & underpasses that are sub-sunk & accessed with only a few steps or a narrow road. The elevated road distance along the highways is kept large as speeds are much higher. The edge of the road is walled /barricaded.

Along NH-4, there is a similar underpass where the highway passes past a village somewhere near Chitradurga, also with barricaded sides.

In China, I have seen these at Guangzhou & at Pudong, near Shanghai. Having friends in China or not is irrelevant here, & I have quoted what I had seen & thought was a great idea as it was well utilized at almost all the locations.

Similarly, on Bellary road (BDA junction, etc), the road rises up & drops back to allow for pedestrian underpass as also vehicle underpasses, but the gradient is too steep & the disturbed road length is large.

Within the city, since speeds are not as high, the distances can be reduced & an optimum reached for safety on the road whilst making it convenient for pedestrians also.

As Srivathsa also mentioned, with a proper median & sidewalk barricades over the length of the road where it is elevated, none of the hazards that you mention are true.

I still cannot figure out why you say that the motorists need to worry about & count the no. of pedestrians passing underneath (Item-4 in your post). The motorists will be grade-separated from the pedestrians.

Your post suggests that you might still not have grasped what I am proposing.

IDS - Thanks & no offence taken.

Srivathsa - I mentioned earlier that disturbed earth must be well compacted before relaying the road. If this were done, the vehicles will not face problems. Storm-drains are cast & are solid, but the slopes up & down are never done up properly in most cases. If proper compacting & load-bearing surfaces are prepared before laying the road, it will be just as fine as the normal road.

You state that this will not be suitable at junctions. I dont think this is correct as the underpasses at BDA, Sanjaynagar, etc. on Bellary rd were all junctions previously. Also, the new plan for KR circle involves grade separation with one level well above the existing street level.

To provide ventilation & light, an opening can be made at the center median & the top covered with fibre-glass sheet. This will allow light through, but prevent rain water. I dont think there is any need for CCTV, but lighting will be required within the subway for night time.

What Das mentioned was in the context of the subways that are fully buried below street level when utilization becomes abysmal, unless pedestrians are forced to use them with no choice. If the subway/s are well utilized, they may not remain dirty & foul smelling & the need for forced draft fans may not be required.

The ideal arrangement of infrastructure for safety & convenience is as per sketch below. The pedestrian underpass is integrated with bus stops & is physically grade-separated from the road overhead. Such infrastructure is quite common in many of the re-developed chinese cities.

Unfortunately for Indian cities, this may be quite impossible as space constraints will come in the way, but can be included in the newer areas.

Blrsri,

There are so many magic boxes on Bellary road & other places too that require vehicles to rise up & then go down without interruption, just as they do at so many other bridges. So, why can't they do it elsewhere too if it helps pedestrians ?  This is not a "hump" as you say, but it is similar to so many other such "bridges".

As mentioned previously, I have seen them in many places & liked their convenience & utility for pedestrians.

Srivatsava,

I had a look at the Nrupathunga rd pedestrian subway (& also one on Bellary road) before I had started this thread. In my opinion, the Nrupathunga rd subway is correctly positioned & provides access to the busbay across the street, but since it is completely below street level, it requires pedestrians to use staircases, which is inconvenient for many. Thus, it's not the same as the one shown on the sketches above. The one illustrated above is only a few feet below surface or almost at grade (with the street elevated to facilitate this), & is thus much more convenient for users.

Having two such subways or four entry /exit points just to avoid crossing the busbay would involve much more extensive work & may not be necessary at Nrupathunga road since it is midway along a single street. If other traffic (other than buses) respect the busbay & not use it, it will be quite safe for pedestrians crossing the busbay after emerging out of the subway since they only have to negotiate buses, if there are any.

The problem is that due to heavy traffic, autos, vans & even some cars tend to enter the busbay & make it inconvenient for pedestrians to cross it. The subway could have been lengthened & extended beyond the busbay to the sidewalk - this would have been safer.

What you previously highlighted was that multiple, integrated subways with several entry /exits were necessary at junctions to provide access from any street side to all other street sides at a junction, which I think is correct. But, are such multiple subways necessary for getting across a single street ?

IDS - I admit that the sketches convey the impression of a "hump". I will try to make a scaled sketch, though it might be more unclear due to the long road length involved !