Total Suspended Solids (TSS) Estimation Over a Section of the Upper Bogota River Basin (Colombia) Through Processing Multispectral Images Captured Using UAV

This article proposes a workflow for estimating the amount of total suspended solids in water in the upper basin of the Bogota river based on the correlation of images obtained using an unmanned aerial vehicle and physical measurements of the quality of the water determined in laboratory from samples collected in field. Main components of the proposed method are: (i) field work - acquisition of UAV images and water samples in situ, (ii) data processing, namely, image processing - including orthophotomosaic generation and index calculation - and laboratory processing of water samples to determined total suspended solids (TSS), (iii) statistical analysis to correlate data derived from UAV images and TSS, and (iv) estimation of TSS using the model generated by band mathematics. Experimental results show that the proposed method allows the estimation of the amount of TSS identifying areas with more than 40 mg/L, with mean discrepancies of 10 % and an RMSE of 2.9. The proposed methodology is promising for continuous monitoring of total suspended solids pollution in the Bogotá river, which is additionally low cost and with high spatial resolution.