  Rivers and canals flowing through cities are often used illegally for dumping
the trash. This contaminates freshwater channels as well as causes blockage in
sewerage resulting in urban flooding. When this contaminated water reaches
agricultural fields, it results in degradation of soil and poses critical
environmental as well as economic threats. The dumped trash is often found
floating on the water surface. The trash could be disfigured, partially
submerged, decomposed into smaller pieces, clumped together with other objects
which obscure its shape and creates a challenging detection problem. This paper
proposes a method for the detection of visible trash floating on the water
surface of the canals in urban areas. We also provide a large dataset, first of
its kind, trash in water channels that contains object-level annotations. A
novel attention layer is proposed that improves the detection of smaller
objects. Towards the end of this paper, we provide a detailed comparison of our
method with state-of-the-art object detectors and show that our method
significantly improves the detection of smaller objects. The dataset will be
made publicly available.
