Green LiDAR is very useful survey tool to provide stream bathymetry in fairly clean waters, where light can penetrate.  Accustical Dopplar equipment such as used by USGS can also provide quality information on specific sites or if accessed by boat.  Less expensive radar detectors could be paired with GPS to help map boatable channels.  Channel stability, sediment supply and stream types may be factors to consider.  

Terrestrial LIDAR gives better bathymetric information on river when there is no water. In case water is present, better go with bathymetric LIDAR.

I consider the best information to use is the Bathymetric LIDAR !

@Iyyappan: Was LIDAR survey carriedout for this project?

yes, praveen