HydroBASINS lev08 watershed · #4080892840
Bassin de Koshi
A watershed (drainage basin) is not a body of water — it is the land area where rainfall converges towards a single river that eventually reaches the sea (or an endorheic basin). Boundaries follow ridgelines.
Crosses 5 administrative regions across 2 countries : Koshi, Madhubani, Sagarmatha, Saharsa, Supaul
Sub-basin area
837,3km²
Upstream area
56 799,4km²
Discharge
1 677,62m³/s
Mean elev.
66m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 2 basins
- Bassin de SUNDARI RIVER213 km²
- Bassin de Koshi48 km²
5 dept-equivalent regions (GADM L2)
- 559.1 km²66.9% of basin
- 208.3 km²24.9% of basin
- 36.6 km²4.4% of basin
- 25.6 km²3.1% of basin
- 6.2 km²0.7% of basin
1 intersecting protected areas
Koshi Tappu - Buffer Zone
IUCN VIWildlife Reserve - Buffer Zone
1.44 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
372 distinct species · 6 655 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 27 species (selected proportionally per kingdom among those with at least one documented interaction here) to keep the graph readable. Hover for details, click to explore the full ecosystem of a species.
ℹ️ The territory contains many more species than displayed and all their documented interactions: the graph is intentionally the structural skeleton (top-N species by composite local score, edges filtered by Serrano 2009 disparity filter α=0.2).
Indicateurs du tissu écologique
Tissu écologique de Bassin de Koshi : 20 espèces dont 1 patrimoniale (LR IUCN CR/EN/VU) reliées par 47 interactions GloBI sur 2 types (connectance 13.4%, filtre Serrano α=0.2). 7 bulles taxonomiques (cascade genre/famille GloBI, ≥3 espèces).
Comparaison sur la connectance du réseau local complet vs distribution nationale (toutes les communes françaises).
Hydroclimate (BasinATLAS lev08)
Mean T°
24,7°C
Annual rain
1 296mm
Moisture idx (CMI)
-0,17
Runoff
670mm/an
PET
1 556mm
AET
879mm
Mean slope
0,1°
Water table
7cm
Forest
1%
Crops
84%
Urban
48%
Protected
0%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)