HIDDEN TROUBLES OF PROTECTION DYKES (A Planning Perspective)
Dykes are generally provided in reservoir vicinity of large dams to protect areas affected by the dam construction. The lengths of potential dykes considered for the Mangla Dam Raising Project range from 1,600 ft to 21,000 ft with a maximum height of 64 ft to 123 ft on many locations. Design requirements of high dams, therefore apply to these dykes. During the planning phase of this project, many studies and observations were made in regard to these dykes, some of these unique in their own way. Detailed studies for the feasibility visualized a number of hidden troubles along with apparent aspects of due consideration. The protection dykes were considered to minimize displacement of affected population and to avoid disruption in socio-economic arrangements. The initial land utilization on maps identified possible alignment and location of the dykes. The construction plan presented a number of apparent issues like socio-economic arrangements and environmental impacts. These could be removed by careful design and construction, maintaining a rigorous and systematic surveillance programme and a significant ongoing commitment of resources. At later stages of the indepth studies for planning and implementation of the protection dykes, certain other hidden aspects came into view. These consisted of operation and drainage issues, safety issues and various geotechnical issues, like adverse foundation conditions over the length of dykes, the remote availability of construction materials involved, the inherent embankment seepage and stability issues and the potential of fines migration and erosion hazard. Finally the comparison of benefits in term of cost and the cost of providing protection dykes indicated that the option is uneconomical and unfeasible. For development of Mega Water Resource Projects such as Mangla Dam Raising, similar studies are very essential for planning and successful implementation. Such projects serve as learning seats for planning and implementation of other projects.
Mangla dam raising Protection dykes Apparent aspects Hidden aspects
Wassay Gulrez Zaheer M.Malik
Junior Engineer,Water and Power Development Authority (WAPDA),MJV Consultants, NESPAK House, Model T Senior Engineer, Pakistan Engineering Services (Pvt.) Ltd., 188-Y, Commercial Area, Phase III, D.H.A
国际会议
西安
英文
1-7
2005-11-01（万方平台首次上网日期，不代表论文的发表时间）