Table 2. Major uncertainties identified in the Upper Guadiana Basin

(we don’t know and we will not know ...)
Incomplete knowledge
(we don’t know but we could get to know ...)
Natural system How do the complex dynamics of groundwater processes affect the day-to-day water level? What are current piezometric levels?
Technical system What are the side-effects of building the structure for water transfer? How much water can be saved with new irrigation technologies?
Social system What would the reaction of stakeholders be to stronger control of illegal extraction? How much water is taken from the ecosystem by illegal water extraction?
What are the economic impacts of reducing the amount of illegal extraction?