The STI of the Bilate catchment ranges from 0 to 140 (Figure 3 (k)). It was classified as very high (0–48), high (49–260), medium (270–720), low (730–1,300), and very low (1,400–2,000) (Table 13). Due to silt deposition, the carrying capacity of stream channels in this catchment will be greatly diminished, and it could cause flooding. The highest STI covers an area of 2,666.3 (47.4%), and the lowest STI covers an area of 1,102.4 (19.6%). STI is sediment transport caused by flowing water (Shafapour Tehrany et al. 2019). The higher STI indicates the area with more sediment transport, and the lower STI indicates less sediment transport. The chance of flooding will be high in areas with low STI values (0–48) because these are the depositional zones.
The STI factor of the Bilate catchment
STI . | Area (km2) . | Area (%) . |
---|---|---|
0–48 | 2,666.3 | 47.4 |
49–260 | 72.9 | 1.3 |
270–720 | 943.4 | 16.8 |
730–1,300 | 840.1 | 14.9 |
1,400–2,000 | 1,102.4 | 19.6 |
Total | 5,625 | 100 |
STI . | Area (km2) . | Area (%) . |
---|---|---|
0–48 | 2,666.3 | 47.4 |
49–260 | 72.9 | 1.3 |
270–720 | 943.4 | 16.8 |
730–1,300 | 840.1 | 14.9 |
1,400–2,000 | 1,102.4 | 19.6 |
Total | 5,625 | 100 |