Need to integrate land subsidence into the legal instruments of Mexico: Morelia, Michoacán case study

The exploitation of an aquifer system causes water table decline when withdrawals exceed the recharge, which in turn activates the process of land subsidence. When sinking is guided by a structural control, the land subsidence is differential and generally is accompanied by earth fissures, fracturing and ground rupturing. All of these effects of the use groundwater generate damage to the infrastructure of cities. In the case of Morelia, Mexico, damages have been observed since 1983, causing economic and social impacts. Reviewing the Mexican legislation, no legal instrument which contemplates the phenomenon of land subsidence and its associate problems was found. Therefore, neither society nor government have legal elements to invoke or claim. However, the proliferation of constructions located in zones identified by scientific studies as risky continues. Accordingly, it is necessary to incorporate land subsidence into legal instruments in order to establish regulation criteria and include them in the urban development plans. These instruments could be the General Law of Ecological Equilibrium and Environmental Protection, the National Water Law, and the Territorial Ecological Zoning.