Real-Time Bridge Scour Monitoring and Evaluation

Science Center Objects

The most common cause of bridge failure is scour, when high-velocity streamflow scours streambed material from around bridge piers and abutments. As of 2017, the National Bridge Inventory listed 265 of Idaho's nearly 4,500 bridges (about 6 percent) as "scour critical." When rivers rise quickly, bridge inspectors have little or no time to mobilize and monitor bridges at risk of scour. Real-time bridge scour monitoring offers a way to remotely monitor sites and to collect long-term data for evaluation. This lowers monitoring costs and reduces the need for field crews to inspect bridges in potentially hazardous situations. 

In cooperation with the Idaho Transportation Department, we have installed sonar devices at three Idaho bridges near existing USGS streamgage stations:

The devices transmit streambed elevation every 15 minutes to the nearby streamgages. That data, along with the other data collected by the streamgages, is then be published to the USGS National Water Information System for public access.

We will also collect hydraulic and geomorphic data to better understand the characteristics of each site. We will continue this pilot study into 2022 and will publish our findings then. Study results will help ITD to decide whether to continue monitoring these sites or to expand the network to other Idaho bridges.