The Peruvian Supreme Court last month ruled that oil exploration in the Cordillera Escalera should be suspended pending environmental review.

The decision, which cited the human right to drinkable water, halted exploration by a consortium in which Canada's Talisman Energy holds the largest (40%) stake, and Spain's Repsol and the Brazilian state company Petrobras have a 30% share each.

This BBC article analyses what is at stake while the oil exploration is now being reviewed by the central government: not just the region's supply of clean water, but biodiversity and the sustainability of Peru's path of development.