Jun 05, 2008

SonTek/YSI Assists China in Dam and Flood Assessments

SonTek/YSI and YSI, Inc., have donated acoustic Doppler profiler measurement systems that will allow hydrologists to gauge the speed and strength of water flow

Fears of flash flooding and massive mudslides continue to threaten thousands in China, who are still working to pick up the shattered pieces of their lives following the massive 8.0 magnitude earthquake on May 12, the epicenter of which was Wenchuan county's Sichuan province.

As strong aftershocks continue to rattle an already weakened infrastructure, and a monsoon season just around the corner, SonTek/YSI and parent company YSI, Inc., have responded by donating acoustic Doppler profiler measurement systems that will allow regional hydrologists to gauge the speed and strength of water flow.

A simple ceremony was held at the Sichuan Hydrology Bureau on May 22, attended by SHB Director Zhang Ting, SonTek and YSI Applications Specialists James Chen and Mark Tepper, as well as other government officials and local hydrologists.

On May 24, after receiving special permission to enter the disaster zone, SonTek's Chen and Tepper, along with local hydrologists, assisted in the collection of data in the Luoshui River in the city of Shifang, which was earlier blocked by rocks and mud.

According to first-hand accounts by Tepper, "the monitoring station was severely damaged and the cableway which is normally operated to make flow measurements was completely destroyed. Both sides of the river were pummeled with large rocks. Sadly, physical injuries to local residents, including children, were also apparent."

Tepper says officials are now worried about a more serious situation that has occurred in the remote city of Beichuan, where 34 lakes have formed due to landslides. Hydrology officials wish to measure the volume and depth of the water in these lakes as quickly as possible. However, Tepper says access is proving to be extremely difficult, with steep cliffs surrounding the lakes and no road access. Helicopters are currently the only method of transportation to the lakes and Tepper says he and Chen are on standby to assist.

The Doppler current surveyors allow for very fast assessment of the overall flood conditions. The advanced hydroacoustic measurement techniques can do in minutes what it normally takes field crew hours to do using conventional instruments.

According to officials from the Sichuan and Shaanxi Hydrology Bureaus and the Sichuan SEPA, more than two dozen hydrology monitoring stations are inoperable or are completely destroyed and are urgently in need of equipment to measure water flow and quality. Reports estimate 400 dams have been damaged and are possible threats to approximately 180,000 residents who live in the dams' paths.