Scientists link road design to fatal Russian flood

Mon, Jul 16, 2012, 01:00

A CATASTROPHIC flash flood that killed at least 164 people in southern Russia on July 7th may have been exacerbated by badly planned road construction, according to scientists studying satellite images of the disaster.

The flood, in which an estimated 50 million cubic metres of water swept through the southern town of Krymsk, was the first significant natural disaster of Russian president Vladimir Putin’s third term.

The government’s response has been strongly criticised, with the emergency situations ministry saying last week that residents had not been properly warned of the impending floodwater, despite an alarm system that highlighted the danger at least four hours previously.

The main cause of the flood was record rainfall, with at least 221mm of rain in the 24 hours beforehand. However, many Krymsk residents believe a discharge of water from the Neberdzhaisk reservoir, south of the town, could have caused the flood, or at least contributed to its strength.

The popular hypothesis is that water was released intentionally from the reservoir to prevent water from overflowing into another nearby town.

Lev Denisov, head of the laboratory of remote sensing at the Institute of Geography of the Russian Academy of Sciences, has another theory which experts say offers a more probable explanation.

The flood’s force, he said, was caused by water being channelled through small openings in a raised highway south of the city.

Using photographs taken from the International Space Station, his team pieced together the path of the floodwater, which he said built up behind a seven-metre-high road embankment south of the town, as well as a raised railway, by late evening on July 6th.

The waters were held back by logjams of debris, which temporarily clogged eight narrow bridge openings.

“When the pressure became too high, the debris clogs burst, unleashing this wall of water,” Mr Denisov said.

He said the height of the flood water was similar to the height of the highway embankment – seven metres – and dismissed the theory that the floods were caused deliberately.

He criticised the construction of the highway and railway, however, which he said should have had wider bridge openings to prevent the build-up of floodwater. – (Copyright The Financial Times Limited 2012)