HydroBASINS lev08 watershed · #4080049070
Bassin de Attanagalu Oya
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 13 administrative regions : Attanagalla, Divulapitiya, Dompe, Gampaha, Ja-Ela +8
Sub-basin area
807,7km²
Upstream area
807,9km²
Discharge
26,58m³/s
Mean elev.
44m
Administrative coverage
13 dept-equivalent regions (GADM L2)
- AttanagallaGampaha · Sri Lanka147.0 km²18.3% of basin
- MinuwangodaGampaha · Sri Lanka129.7 km²16.1% of basin
- 92.0 km²11.4% of basin
- 89.0 km²11.1% of basin
- 81.0 km²10.1% of basin
- DivulapitiyaGampaha · Sri Lanka61.5 km²7.6% of basin
- 46.7 km²5.8% of basin
- RuwanwellaKegalle · Sri Lanka37.5 km²4.7% of basin
5 moreFull L2 list
- Ja-Ela35.2 km² · 4.4%
- Warakapola34.4 km² · 4.3%
- Negombo8.6 km² · 1.1%
- Wattala7.1 km² · 0.9%
- Dompe5.4 km² · 0.7%
6 intersecting protected areas
Muthurajawela
IUCN IVSanctuary
5.46 km² overlap
Horagolla
IUCN IVSanctuary
2.77 km² overlap
Kotakanda
IUCN IbReserved Forest
2.20 km² overlap
Maimbulkanda - Nittambuwa
IUCN IVSanctuary
1.47 km² overlap
Dambukanda
IUCN IbReserved Forest
0.32 km² overlap
Mahakanda
IUCN IbReserved Forest
0.25 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
2 433 distinct species · 38 147 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 37 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 Attanagalu Oya : 33 espèces dont 3 patrimoniales (LR IUCN CR/EN/VU) reliées par 35 interactions GloBI sur 4 types (connectance 5.3%, filtre Serrano α=0.2). 4 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°
27,1°C
Annual rain
2 470mm
Moisture idx (CMI)
0,38
Runoff
1 048mm/an
PET
1 503mm
AET
1 395mm
Mean slope
2,5°
Water table
87cm
Forest
4%
Crops
65%
Urban
79%
Protected
0%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)