Debashis Bose, Niladri Gupta
Consulting Engineering Services (I) Private Limited
DD 18 / 8, Sector – I, Salt lake, Kolkata 700064
e-mail: [email protected]
Tel. Nos. : + 91 – 33 – 23597305-07/8809
Fax No. : + 91 – 33 – 23597304
In the present Indian scenario there is a major shift in transportation system from railways towards the road sector, which has envisaged the Government of India to facilitate development of roads and highways as exemplified by the Golden Quadrangle Program etc. New roads and highways are being designed and built, as well as the existing highways are being upgraded to 4/6 lanes along with the super expressways. The technical know-how of present day road designing depends on various factors viz. socio-economic criteria, demographic analysis, landuse / landcover pattern, topography, etc.
In this context, terrain analysis may be considered as the prime requisite in the planning phase for providing an insight to the engineers regarding the landform features to overcome the potential engineering problems viz. The site-specific engineering aspect of a Highway passing through an alluvial terrain is different from a Highway passing through a degradational landform or a hilly terrain.
In Highway / Super Expressway designing, location of a line is the most important criteria in terms of Geo-referenced Physiographic configuration which include, baseline information: viz.
In this regard it may be mentioned that for cost modeling drainage pattern analysis helps in determining the number and type of bridges or culverts to be constructed, landform categories helps in determining the type of retaining wall or check dam to be erected and Landuse / Landcover study determines whether an alignment should be drawn over a double cropped area or a sparsely vegetated land.
In this regard the spatial baseline information could be generated through terrain analysis and classification with morphogenetic approach (Meijrink, 1988) using Remote Sensing data. Space borne Remote Sensing and Geographical Information Systems are the most modern tool for generation of the aforesaid spatial data with temporal changes and subsequent integration and analysis of the aspatial data to conclude on “strategic datasets” (i.e. Geoinformation) giving emphasis on type of engineering work to be carried out. (c.f. Chakrabarti, 2000)
The Geoinformation provide vital information regarding ‘vulnerable land units’ for geotechnical adjustment (through structural means) and social adaptations (non-structural means) along the proposed Highway route (cf. Numan et al, 1995) (Fig.1). These new technologies could be utilized by the planners / executives for successful planning and execution of engineering activities and to increase the bearing strength of the road.
Activity Flow Chart
1 Flood Damage of the Panagarh – Moregram ADB road during the September 2000 devastating flood in West Bengal, India:
The ADB road is an important connectivity between NH-2 and NH-34 covering a distance of 150 Km. and passes across two major rivers of South Bengal namely Ajay and Mayurakshi. These rivers are characterized by a number of abandoned spill channels. It may be mentioned that flash flooding is a common phenomenon in the Ajoy River, which is also having a number of flood time spill channels and generally used as cropland now a days. The ADB Highway is passing over such a spill channel in and around Satkahania – Basudha area, Barddhaman district, West Bengal, India (Chakrabarti, Choudhury et.al. 2002). In this site only humes pipe are given as water pass way based on sparse information (cf Akinyedi, 1990) without giving insight to the factual data regarding the monsoonal activity of the spill channel. However multi-seasonal Remote Sensing data (IRS 1D, LISS III) reveals the presence of this loop channel (Photo 1a) locally known as Bidya River with its branch off point at Satkahania presently blocked by the embankment. During the September 2000 flood with breaches in the embankment at Satkahania point and rejuvenation of the aforesaid spill channel the road was damaged severely (Photo 1b) as the constructed water pass way was insufficient to accommodate the flood time flow – here lies the importance of terrain analysis with usage of Remote sensing data; some box culvert / small bridge may be constructed for avoiding such predicament.
2 Protection of Super Strada from Landslides in Southern Italy:
In Armento, Policoro province, Southern Italy the “Super Strada” (Super Expressway) passes through the Mediterranean schist phyllite and marl clay hills or ‘Calinchi’ prone to landslides. Detailed mapping using aerial photo and Remote Sensing data with field survey lead to the positioning of a number of “via ducts / check dams” (Photo 2 a,b,) as well as guard walls (Photo 2c) in the area to protect the “Super Strada” from damage due to frequent landslides. (Verstappen, 1988)
Comparative analysis of the case studies indicates the significance of Remote Sensing data for landform and drainage pattern analysis for safety of infrastructural designs in the planning stage itself. Usage of Remote Sensing and GIS technologies may be considered as the essential prerequisite for careful physical spatial planning to make optimum use of the roads as communication links for all seasons as a great amount of money are invested in planning and construction activities of the roads.
Appropriate integration of different spatio-thematic information with aspatial data in GIS environment demand human resources development for handling and processing of the database of multidisciplinary nature to conclude on user orientation.
- Chakrabarti, P; Choudhury, S; 2002 – Spatial Planning and Management of Land and Water Resources Kunur Basin, Barddhaman district, West Bengal, India. (unpublished Report, Remote Sensing Cell, DST & NES, Govt. of West Bengal)
- Chakrabarti, P; 2000 – RS and GIS : Spatial format for sustainable resource development. MGMI Transactions, (1&2), 97. pp. 29-37.
- Numan, NMS; Al-Bararr, SKS; 1995 – Highway route selection in Northern Iraq using terrain evaluation from aerial photographs. ITC Journ. (Vol. 2). pp 120-126.
- Akinyedi, J. O.; 1990 – A geotechnical GIS concept for Highway route planning. ITC Jour. (Vol. 3) pp. 262-269.
- Niemann, O; Barendregt, R; Genderen, Van J; 1989 – Working Group reports : Symposium on ” Aerospace Survey and Natural Disaster Reduction”. ITC Journ. 1989 (3/4). pp 194-199. Meijrink, A.M.J. 1988 -Data acquisition and data capture through terrain mapping units. ITC Jour. Sp. Issue (1) pp. 23-44.
- Verstappen, H. Th.; 1987-Geomorphology, Resources, Environment and the Developing World. International Geomorphology, Part-I, Ed-V.Gardiner, Jhon Willy & Sons. Ltd. pp. 45-62. Verstappen, H. Th.; 1985 – Applied Geomorphology, ITC Lecture Notes pp. 48.
The authors express their sincere thanks to Mr. Shankar Bose, Executive Director, CES (I) Pvt. Ltd., for according permission to present the paper. However, the views expressed in this paper are primarily of authors own and not necessarily of the organization to which they belong. Our sincere thanks to Dr. P. Chakrabarti, Principal Scientist, DST & NES, Govt. of West Bengal for his continuous guidance and appropriate suggestions for preparation of this paper.