HydroBASINS lev08 watershed · #4080049680
Bassin de Mahaweli River
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 : Hingurakgoda, Kantalai, Kinniya, Lankapura, Medirigiriya +4
Sub-basin area
1 064,4km²
Upstream area
10 161,4km²
Discharge
235,48m³/s
Mean elev.
30m
Administrative coverage
Hydrographic chain
▼ Drains into
Outlet (drains to ocean / endorheic)
▲ Receives from 2 basins
- Bassin de Eriga_Oya_Canals1185 km²
- Bassin de Mahaweli River455 km²
9 dept-equivalent regions (GADM L2)
- 330.6 km²31.2% of basin
- 213.9 km²20.2% of basin
- 199.3 km²18.8% of basin
- 93.4 km²8.8% of basin
- 92.1 km²8.7% of basin
- 89.7 km²8.5% of basin
- 20.2 km²1.9% of basin
- 18.2 km²1.7% of basin
1 moreFull L2 list
- Lankapura1.3 km² · 0.1%
13 intersecting protected areas
Somawatiya Chaithya
IUCN IINational Park
290.79 km² overlap
Mahaweli
IUCN IbReserved Forest
139.22 km² overlap
Chundankadu
IUCN IbReserved Forest
127.50 km² overlap
Kelegama
IUCN IbReserved Forest
43.26 km² overlap
Trikonamadu
IUCN IVNature Reserve
35.16 km² overlap
Seruvila - Allai
IUCN IVSanctuary
32.36 km² overlap
Ralapanawa
IUCN IbReserved Forest
16.73 km² overlap
Vappiah Verugal
IUCN IbReserved Forest
16.16 km² overlap
Flood Plains
IUCN IINational Park
12.06 km² overlap
4 more protected areassorted by overlap area
Kaudulla
IUCN IINational Park
10.77 km² overlap
Borawewa
IUCN IbReserved Forest
9.84 km² overlap
Aluthoya
IUCN IbReserved Forest
3.57 km² overlap
Anawulandawa
IUCN IaConservation Forest
1.06 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
183 distinct species · 780 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 41 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 Mahaweli River : 37 espèces dont 3 patrimoniales (LR IUCN CR/EN/VU) reliées par 36 interactions GloBI sur 4 types (connectance 4.4%, 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°
27,6°C
Annual rain
1 603mm
Moisture idx (CMI)
0,09
Runoff
597mm/an
PET
1 465mm
AET
997mm
Mean slope
0,5°
Water table
29cm
Forest
36%
Crops
13%
Urban
3%
Protected
55%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)