The flow reduction in America’s Colorado River has left Lake Powell – the country’s second-largest reservoir – at just 23 per cent, its lowest level since it was filled in the 1960s.
Federal officials are now studying the possibility of overhauling the dam so that it can continue to generate electricity at critically low levels.
Kyle Roerink, Executive Director of the environmental group Great Basin Water Network , said: “There is now an acknowledgement, unlike any time ever before, that the dam is not going to be suitable for 21st century hydrology. Things will have to change pretty quickly.”
Proposals under discussion include: penetrating the dam’s concrete to make new lower-level intakes; installing a new or reconfigured power plant; and tunnelling a shaft around either side of the dam to a new power plant.
Leslie James, Executive Director of the Colorado River Energy Distributors Association , said: “Any of the options are going to be very expensive and they’re going to be very time-consuming.”
Estimates of the cost of the alternatives range from $500 million to $3 billion.