Author : Patmajum

Mullaperiyar dispute is non-conventional, hence legal and technological questions are difficult to answer with adequate level of certainty.

• Firstly, the dam is storage cum diversion structure, not absolutely gravity type. A designer cannot guarantee safety, once sliding and overturning forces are balanced with the weight of the dam within the permissible limit of the bearing capacity of the foundation, as safety against seepage through the dam body and foundation may not be strong and healthy in lime surkhi filled dams. If it increases with time and with subsequent heightening, it could be a sign of increase in water pressure, which may cause piping and conduit flow.
• Seismic effects also increases in proportion to the weight of the dam and mostly generates tensile stresses to develop fissures, gradually increasing in length and aperture with passage of time.
• Increase in seepage could be due to increase in hydraulic gradient across the dam section or lengthening and widening of the fissures and piping effects in the foundation.

Mullaperiyar dam was a gesture of one state towards the other. Over the years with change in socio-economic condition of the region, it turned out to be more like a rivalry as both the states focussed on their own interests. Kerala’s claim that the dam is old enough to be replaced by a new one cannot be justified as age of a dam pertains to its storage capacity..

On the other hand, Tamil Nadu's stand on dam safety can also not be confirmed by the best of the available technologies and skills. In such a situation a general gesture should prevail between the two satets. Tamilnadu should maintain reservoir water level in Mullaperiyar dam much below the danger level, to the extent of a solely diversion type of structure, by canalizing water to newly constructed storage reservoirs on their land and give respite to the keralites and their tourism, so that demand of a new Mullaperiyar dam vanishes. On the other hand Kerala must ensure lease of the submergence area for many years to come. Many such disputes would follow and are unavoidable under rapid change in socio-economic status.