An investigation of spatial variation of suspended sediment concentration induced by a bay bridge based on Landsat TM and OLI data

• Analysis of Landsat TM and OLI data can reveal SSC variation induced by a bay bridge.
• SSC increases downstream when low turbidity upstream, SSC decreases when high turbidity upstream.
• Local SSC distribution is mainly affected by the interaction of bridge piers and water currents.

This study investigates the spatial variation of suspended sediment concentration (SSC) induced by Hangzhou Bay Bridge (HBB) in the coastal waters of the East China Sea. Based on Landsat Thematic Mapper (TM), Operational Land Imager (OLI) data and in-situ measurements, spectral characteristics of waters in Hangzhou Bay and SSC retrieved from near infrared single band have been analyzed. The results revealed significant difference of SSC in the water on two sides of HBB. SSC increases downstream of the bridge under conditions of low turbidity (SSC < 300 mg l−1) upstream water, while SSC decreases when high turbidity water (SSC > 400 mg l−1) upstream. This study shows that the interaction of bridge piers and currents has important influences on SSC distribution by inducing hydrodynamic factors and by changing suspended sediment transport. Remotely sensed data with high spatial resolution as TM and OLI can be applied to investigate SSC variations induced by a bridge in the bay area.