HydroBASINS lev08 watershed · #4080049750
Bassin de Rambaken 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 24 administrative regions : Addalachchenai, Ampara, Bibile, Eravur Pattu, Eravur Town +19
Sub-basin area
3 117,8km²
Upstream area
3 117,8km²
Discharge
2,71m³/s
Mean elev.
70m
Administrative coverage
24 dept-equivalent regions (GADM L2)
- 562.9 km²18.1% of basin
- 488.4 km²15.7% of basin
- 466.7 km²15.0% of basin
- 322.8 km²10.4% of basin
- PadiyathalawaAmpara · Sri Lanka317.0 km²10.2% of basin
- 174.3 km²5.6% of basin
- 159.5 km²5.1% of basin
- 126.8 km²4.1% of basin
16 moreFull L2 list
- Samanthurai89.2 km² · 2.9%
- Bibile51.4 km² · 1.7%
- Navithanveli49.2 km² · 1.6%
- Manmunai South and Eruvilpattu35.3 km² · 1.1%
- Eravur Town27.3 km² · 0.9%
- Koralai Pattu (Valachchenai)26.8 km² · 0.9%
- Manmunai Pattu (Araipattai)25.4 km² · 0.8%
- Ninthavur24.3 km² · 0.8%
- Sainthamarathu21.1 km² · 0.7%
- Karativu13.6 km² · 0.4%
- Ampara12.0 km² · 0.4%
- Manmunai North10.1 km² · 0.3%
- Kalmunai6.1 km² · 0.2%
- Addalachchenai2.9 km² · 0.1%
- Kattankudy2.5 km² · 0.1%
- Rideemaliyadda0.8 km² · 0.0%
13 intersecting protected areas
Nuwaragala
IUCN IbReserved Forest
713.19 km² overlap
Unnichchi F.R
IUCN IbReserved Forest
73.32 km² overlap
Maduru Oya
IUCN IINational Park
68.14 km² overlap
Gal Oya Valley North - East
IUCN IVSanctuary
32.42 km² overlap
Varadithacholai
IUCN IbReserved Forest
25.26 km² overlap
Nelugala
IUCN Not ReportedJungle Corridor
24.02 km² overlap
Kithulwewa F.R
IUCN IbReserved Forest
17.80 km² overlap
Rukamwewa F.R
IUCN IbReserved Forest
13.65 km² overlap
Kokagala (Weli Kumbura)
IUCN IbReserved Forest
12.84 km² overlap
4 more protected areassorted by overlap area
Gal Oya
IUCN IINational Park
10.82 km² overlap
Budhangala
IUCN IVSanctuary
10.34 km² overlap
Samanagala
IUCN IbReserved Forest
2.90 km² overlap
Ethaleikulum EPA
IUCN IVEnvironmental Protection Area (EPA)
0.30 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
1 530 distinct species · 8 704 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 43 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 Rambaken Oya : 39 espèces dont 2 patrimoniales (LR IUCN CR/EN/VU) reliées par 39 interactions GloBI sur 4 types (connectance 4.3%, 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°
27,0°C
Annual rain
1 915mm
Moisture idx (CMI)
0,23
Runoff
736mm/an
PET
1 471mm
AET
1 072mm
Mean slope
2,9°
Water table
150cm
Forest
20%
Crops
20%
Urban
10%
Protected
25%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)