Land Creeping occurring in and around Pashupati: Geo- Scientist
29th Mar, 2017 | Tourism Mail Crew
Dr. Ranjan Kumar Dahal is the Geo- Scientist of Nepal. He along with his team of 3 members are on study about the land slopes of world heritage site of Nepal namely Pashupatinath, Swayambhunath and Chqangunarayan Temple. In an interview with Tourismmail Dahal point out the risk factors in and around the Pashupatinath Temple and his later findings.
Q: Please share us your findings in brief.
Mr. Dahal: We are working for the stability of the Pashupati Kshetra and Swayambhu Area and Changu Narayan Area from last 10 years and this is our regular process of the observations and collecting data. When we look on the Pashupati area specially the Pashupati Temple and the river bank of the Pashupati Temple below the staircase from where we can go to the Pashupati Temple. In that area we found that basically the whole mass in that area is now in continuous creep and this is the main thing we have explore more detail in coming future because they are creating lots of cracks on the slope and the bulges are also there and in the Western Part of the river or the left bank of the Bagmati river we have a regular platform where we have regular "Aarati" activity. In that area also we notice few bulges and the deformation on the walls, which clearly suggests that the mass is continue moving down because the area consist of the fine material and of course the material falling down from the uphill section of the Slesmantak Forest. This clearly shows that the area is in the threat of being creep and we are working on that particular aspect right now.
Q: The techniques used at the time of research or the observation.
Mr. Dahal: The techniques that are used in the field is the observations because as you know a lots of cracks on the slope, the moving masses, bulges and the cracks on the joint of the paved stones clearly suggest that the mass is moving down. Another interesting thing is that we have many Shivalinga over there, the temple has many Shivalinga and the Shivalinga are just around various places around the/ on the slope. What we can find is that the Shivalinga now is going up and the base of the Shivalinga is now going down. As a result, now what we can see is that the upper part of the Shivalinga that we call Shiva is already seen and below we have Bishnu and Bishnu part is also, we can see in many areas. It means that the base of the whole Shivalinga is going down, it also suggest that whole mass is on the creep, continue creep and subsidence is there and there is deformation in Shivalinga statue.
Q: The level of danger in and around Pashupati Area.
Mr. Dahal: If you take the level of dangers like in terms of category of hazard level then I should say it is in the medium level of danger right now, it is not in the higher risk not in the lower risk. It is in the medium risk in that sense like if you make some change on the outer region, if you make a change or enhances the sub surface percolation of water because of some reason then the problem will be very much, the hazard level will be very high. Medium level of hazard means like; if you keep some mitigation measures in this present condition then things will be more control and the creep will be retarded very soon. In my opinion the Pashupati temple right now in the Eastern side of the temple from the Basuki Krishna Temple in the Pashupati area along this line we have to take care of the cracks on the surface regularly. If we have the cracks over there we have to seal it very soon as far as possible we have to seal it and drainage on that area should be managed properly. Not even a single drop of water doesn’t permit single drop of water to peculate inside the soil strata, let them drain from the surface; above surface or some surface taint and it will be very helpful to stop the movement of the creep and this is the thing we have to take care of the western part of the slope also.
Q: What can be done to prevent and preserve the Pashupatinath Area?
Mr. Dahal: Actually the creep on the Western Area of Pashupatinath it was happen because of the continuous slippage from the “Bramhanal”. We have a Bramhanal there which is very old drainage system which brings a lot of water or “Jal” from inside the Temple where the pilgrims offers jals to the goddess and it comes through a small drain hole and comes in a small drain but it is not a very well sealed drain it is a very much open kind of drain thus made by the stone and then they cover it and it is just running from the slope. Along this slope we have the unlined very much fragile drainage system there and it is contributing lot of water to the surrounding soils and it helps to create the high water pressure in the area and as a result nearly five or six years ago we faced the landslide in the Eastern gate of Pashupati temple. Some what they managed the Pashupati Area Development Trust managed the just repair the things and then they maintained the slopes and now they have well prepared staircase over there but the problem is not solved correctly still we can face more bulges in the ground, we can notice those things when we visit the site and observe very sincerely.
My Suggestion is that we have to prepare the perfect drain system for the Bramhanal, this is very much important and another thing what we notice during our site visit various times this year and last year also what we realize is that the surface drain system is not well prepared over there as a result the rain water, when we have lots of rain, we have rainwater there and of course the water collected from the roofs are also not properly drained under the slope and it peculates through the cracks, swallow open space in the stone paved area and as a result all the water goes to the underground soil surface/ soil materials as a result the underground soil materials becomes more saturated and from the geotechnical data we can realize that in the Pashupati and suround the Pashupatinath Temple we have clay and silt and fine sand also. Clay and silt is little bit low but medium and fine sand are in the higher amount. As a result the sand always percolates the water it has very good permeability, it can drain water very easily and the lot of water accumulate in the soil strata above the clay strata as a result we will have a lot of poured pressure over there and this flow of the pressure always creates the landslide or creep slippage situation in the slope and this is the main reason we are having and we have to control those parameters specially controlling of the Bramhanal and controlling of the sub surface and surface drainage system in Pashupati area is a major challenge we are facing right now.