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To avoid upconing and/or lateral saltwater encroachment discharge has to be limited, sometimes to a small fraction of the well yield. This is seldom understood by abstractors, but has to be enforced by management rules and supported by a groundwater users’ association.  Poor well construction or design, such as excessive depth, screens facing salinized or easily salinizable layers, and poor protection against corrosion around saline water aquifers or aquitards. It may be necessary to close down or partially grout some wells.

Upconing of saline water À be it recent or old marine water, or deep-seated saline water À is a common process for deep wells and intensively exploited wells. Sometimes it is not easily identified. Often trends that are easy to observe are sought to define when there is excessive groundwater abstraction. It is often called overexploitation, although this term is not a useful one and should be abandoned (Custodio, 2002). There are trends that are not easy to observe À or plain facts À that can be substituted for a sound aquifer system study.

But in any case the right solution for management and sustainable use seems to be power sharing between a public institution and stakeholders with collective participation. Aquifer protection implies protection of the role of low permeability layers, adequate well and borehole design and construction, and the plugging and sealing of abandoned wells and boreholes. Protection does not mean that every well or water right has to be protected. Management implies a trade-off between allowable saltwater penetration and sustainable groundwater abstraction in a dynamic framework.