Credit: UNU-INWEH
By 2050, most people on Earth will live downstream of tens of thousands of large dams built in the 20th century, many of them already operating at or beyond their design life, according to a UN University analysis.
The report, Ageing water infrastructure: An emerging global risk, by UNU s Canadian-based Institute for Water, Environment and Health, says most of the 58,700 large dams worldwide were constructed between 1930 and 1970 with a design life of 50 to 100 years, adding that at 50 years a large concrete dam would most probably begin to express signs of aging.
Ageing signs include increasing cases of dam failures, progressively increasing costs of dam repair and maintenance, increasing reservoir sedimentation, and loss of a dam s functionality and effectiveness, strongly interconnected manifestations, the paper says.