Scientists at Brigham Young University have discovered a way to measure defects in bridges by listening to the sounds they make when impacted by drops of water.

Echo location is the basic principle at work here, a technique used for all kinds of things, from finding underground deposits of oil and gas to radar and sonar. But the BYU researchers were able to diagnose structural flaws in bridges using nothing more than a spray of water.

Acoustic testing of bridges at present uses solid objects like hammers and chains. It is hoped that the water-dropplet testing will be quicker, cheaper and more accurate once a commercial application is created.