This paper focuses on the methodology used in quantitative stream habitat assessment. For the Lao stream, we investigated presence of fish and UAV photographs and calculated green coverage by using the Visible Atmospherically Resistant Index (VARI). The National Center for Computation Hydro-Science and Engineering 2D
(CCHE-2D) model was used to simulate the velocity and depth of water in the river segment. The discharges were 1.0
and 514 cubic meters per second (m3/s). We used the simulated velocity and water depth values of each element to
identify the aquatic habitat type and calculate Shannon’s diversity index. Based on the habitat suitability curve for
Onychostoma alticorpus and Rhinogobius gigas, we calculated the habitat suitability indices and Weighted Usable
Areas (WUA) for different sites along with discharges. The Froude numbers were simulated by the CCHE-2D model,
which we used to identify suitable areas of the river segment for fish habitats.
Key Words: Quantitative Assessment, Habitat Suitability Index, Froude Number.