Prof. G.T. Thong
Department of Geology, Nagaland University
Our roads and bridges do not last long because that is how we make them; to last for very short durations. If they last too long, what will we eat tomorrow, right? On careful consideration, our road construction is the culprit. There is an acute lack of engineering. The same old stupidly lame excuses – too much rainfall and our weak soils. There are other terrains that are much more severe, and with much more adverse climatic conditions, but that do not have our acute problems.
To begin with, our concept of drains is totally lacking. Perhaps there is (an artificial) scarcity for funds in Nagaland! Our drains, both artificial and some natural within town and municipal limits are too shallow to carry the monsoon waters, which end up spilling onto the pathetic structures we once knew (many decades back) as roads. In numerous places in Kohima town itself we see artificial drains above road level. Therefore, instead of water flowing into the drains from the roads we see the rare reverse phenomena noted only in this part of the world. Excellence in Engineering! Much of our roads are concave upwards. Real roads (in other parts of the world), including in our neighbourhood (e.g., Shillong), are built convex upwards so that any water on the surface immediately flows to the sides, which are normally lined with drains. These drains train waters to the nearest natural steam channels.
Then we have roads that are widened without the concept of mitigation measures (lacking in our dictionaries). Twenty foot or higher, almost vertical walls (80°-90°) are excavated with puny retaining walls (8-9′) built to hold up the hillside (e.g., stretch around Hotel Vivor. Result – continuous debris falls. But the bigger danger, yet to come, will be with larger collapses; pedestrians / vehicles, better watch out!
Our Two Lane concept faces the same acute problem. The NH 2, between Botsa and Chiechama was hit by massive debris slides during July-August 2011. The simple reason was that the slope was already very weak. In such areas stabilisation measures should have been in place as soon as excavation ended. However, the high slope was left to fend for itself.
An acutely needed diversion to tackle traffic congestion was sanctioned and work began in earnest. No sooner did works begin, the two hill slopes (box cut between the north-eastern slope of Raj Bhavan and south-western slope of the War Cemetery) slid down. After great ensuing drama and multiplication of costs, the road was opened, but for light vehicles only. If the concerned Agency or the Contractor conducted any geotechnical tests, they would have known that the slope was bound to fail as the shear strength of the soils was too low and the slope angle too great, much greater than the internal friction angle of the slope mass. The Government of Nagaland does have a geotechnical laboratory near the DC’s office in Dimapur. Hopefully the equipments have not rusted from over-use! One wonders if the contractors are left to their own devices in any civil works, or are they supervised by the Government Engineers all through the course of the work? From the nature and quality of work we see around, the former best fits the picture.
Our road construction, as well as other civil works, is also badly hampered by the Land Owner concept. Everything under the sun should be constructed by the landowners, with or without the requisite expertise, else work is stopped. Perhaps my studies were grossly inadequate, but I have not heard of this Land Owner’s / Land Donor’s / Land Sellers quota elsewhere.
Bridges built in different parts of the world in recent times are truly wonders; nothing short of Excellence in Extreme Engineering. The lesser said about our Bridges, the better. Bridges are built to last centuries; in fact there are a number of bridges built in many parts of the world that are still standing after having braved the elements for centuries. The Arkadiko Bridge (arch bridge) was built in 1300 BC. It is really a shame that our bridges do not last even 30-40 years; truly a statement of Extremely Poor Engineering. The sites for the Abutments and Piers, and their design, should be paid particular attention. Moreover, the annual and seasonal discharges under the bridge should be given due consideration, along with knowledge of the erosivity of river waters, particularly during storms. The maximum height of water flow in the channels over the decades should always be considered. With climate changing so rapidly, what we had so far is just a warm up exercise. The next few decades will be very different from what we individuals have seen in our short time here on earth.
Moreover, we have probably also conveniently ignored the character of the soils and depths of the bedrock, and their geological conditions. The Government has a full-fledged Directorate of Geology & Mining at Dimapur. The expertise of these Geologists should be fruitfully utilised for detailed investigations prior to construction, or even in selection of suitable sites. The depths of the bedrocks and their structural condition should be known. For this, geophysical surveys are also a must. All these should end up with drilling at selected sites for confirmation of bedrock status. Placing a bridge across any river after that will ensure that we remain connected to the other side, even for centuries.
However, the mess continues beyond engineering. There is the ever cancerous demand of percentages/cuts for the pockets from all and sundry. Then we have the similar but much larger, slyly respectable demand – For Party Funds. Not to be outdone in this rat race, the more than eager Sovereignty Warriors extort left and right. Result: NO ROADS and COLLAPSING BRIDGES.
Our generation has no hope and no future. We will continue voting for money. We definitely were all born optimists but gradually down the line we have, with very rare exceptions (?), grown very pessimistic. We therefore, now pray for GOOD Roads & Bridges … for our grandchildren, most of who will be born soon. Amen!