HydroBASINS lev08 watershed · #4081155740
Bassin de Malwathu 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 11 administrative regions : Ipalogama, Kekirawa, Maha Vilachchiya, Medawachchiya, Mihinthale +6
Sub-basin area
708,8km²
Upstream area
1 119,3km²
Discharge
15,16m³/s
Mean elev.
100m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 2 basins
11 dept-equivalent regions (GADM L2)
- 220.5 km²31.2% of basin
- 161.0 km²22.8% of basin
- 89.3 km²12.7% of basin
- 85.5 km²12.1% of basin
- 53.8 km²7.6% of basin
- 43.3 km²6.1% of basin
- 21.8 km²3.1% of basin
- 11.2 km²1.6% of basin
3 moreFull L2 list
- Rambewa8.5 km² · 1.2%
- Ipalogama7.7 km² · 1.1%
- Medawachchiya3.3 km² · 0.5%
6 intersecting protected areas
Mihintale
IUCN IbReserved Forest
26.99 km² overlap
Yodaela
IUCN IbReserved Forest
9.35 km² overlap
Wellaragama
IUCN IbReserved Forest
6.80 km² overlap
Nuwaragama
IUCN IbReserved Forest
6.03 km² overlap
Anuradhapura
IUCN IVSanctuary
1.20 km² overlap
Ulukkulama
IUCN IbReserved Forest
0.43 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
654 distinct species · 14 622 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 36 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 Malwathu Oya : 31 espèces dont 3 patrimoniales (LR IUCN CR/EN/VU) reliées par 35 interactions GloBI sur 4 types (connectance 5.6%, 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°
27,2°C
Annual rain
1 364mm
Moisture idx (CMI)
-0,14
Runoff
446mm/an
PET
1 587mm
AET
1 039mm
Mean slope
0,8°
Water table
55cm
Forest
18%
Crops
24%
Urban
16%
Protected
12%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)