 These include groundwater overexploitation, land subsidence, the risk of major flooding, the impacts of increasing urbanization, poor water quality and intermittent supply, inefficient water use, a low share of wastewater treatment, health concerns about the reuse of wastewater for irrigation, and limited cost recovery for water.Infrastructure coverage in terms of access to a piped water connection or to sanitation, which is used to monitor the Millennium Development Goals for water supply and sanitation, is almost universal in Greater Mexico City and as such does not constitute a challenge.The Greater Mexico City's exponential population growth has depleted its groundwater resources.