HydroBASINS lev08 watershed · #4080049010
Bassin de Kaluganga
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 9 administrative regions : Bandaragama, Bulathsinhala, Dodangoda, Horana, Kalutara +4
Sub-basin area
347,1km²
Upstream area
2 942km²
Discharge
158,49m³/s
Mean elev.
28m
Administrative coverage
Hydrographic chain
▼ Drains into
Outlet (drains to ocean / endorheic)
▲ Receives from 2 basins
- Bassin de Kuda Gaga915 km²
- Bassin de Kaluganga418 km²
9 dept-equivalent regions (GADM L2)
- 89.0 km²25.7% of basin
- 80.6 km²23.3% of basin
- 54.1 km²15.7% of basin
- BandaragamaKalutara · Sri Lanka41.6 km²12.0% of basin
- MadurawalaKalutara · Sri Lanka34.2 km²9.9% of basin
- 31.7 km²9.2% of basin
- 11.8 km²3.4% of basin
- BulathsinhalaKalutara · Sri Lanka1.6 km²0.5% of basin
1 moreFull L2 list
- Mathugama1.0 km² · 0.3%
1 intersecting protected areas
Bolgoda EPA
IUCN VEnvironmental Protection Area (EPA)
4.26 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
480 distinct species · 4 592 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 39 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 Kaluganga : 34 espèces dont 2 patrimoniales (LR IUCN CR/EN/VU) reliées par 39 interactions GloBI sur 3 types (connectance 5.3%, filtre Serrano α=0.2). 5 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°
26,9°C
Annual rain
3 338mm
Moisture idx (CMI)
0,57
Runoff
1 411mm/an
PET
1 432mm
AET
1 395mm
Mean slope
3,2°
Water table
97cm
Forest
1%
Crops
60%
Urban
68%
Protected
0%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)