HydroBASINS lev08 watershed · #2080033680
Bassin de Toreselva
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 5 administrative regions : Drammen, Hurum, Sande, Svelvik, Vaale
Sub-basin area
143,4km²
Upstream area
143,4km²
Discharge
3,1m³/s
Mean elev.
152m
Administrative coverage
5 dept-equivalent regions (GADM L2)
- 60.7 km²42.1% of basin
- 59.3 km²41.1% of basin
- 10.1 km²7.0% of basin
- 1.0 km²0.7% of basin
- 0.0 km²0.0% of basin
15 intersecting protected areas
Petersætra og Trestikledalen
IUCN IaNature Reserve
3.09 km² overlap
Trestikle
IUCN IaNature Reserve
1.22 km² overlap
Sandebukta
IUCN IVProtected Landscape
1.12 km² overlap
Sandebukta
IUCN Not ReportedEmerald Network
1.12 km² overlap
Grunnane
IUCN IaNature Reserve
0.94 km² overlap
Grunnane
IUCN Not ReportedEmerald Network
0.94 km² overlap
Kommersøya og Gåserumpa
IUCN Not ReportedEmerald Network
0.49 km² overlap
Kommersøya
IUCN IaNature Reserve
0.43 km² overlap
Langøya
IUCN IaNature Reserve
0.21 km² overlap
6 more protected areassorted by overlap area
Gåserumpa
IUCN IaNature Reserve
0.06 km² overlap
Bjørkøya
IUCN IaNature Reserve
0.06 km² overlap
Killingholmen
IUCN IaNature Reserve
0.01 km² overlap
Kulpa
IUCN IIINatural Monument
0.00 km² overlap
Bekkeskjæret
IUCN IVWildlife Conservation Area
0.00 km² overlap
Søndre Verksøya
IUCN IaNature Reserve
0.00 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
2 627 distinct species · 62 129 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 30 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 Toreselva : 20 espèces reliées par 88 interactions GloBI sur 4 types (connectance 17.7%, filtre Serrano α=0.2). 12 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°
5,9°C
Annual rain
751mm
Moisture idx (CMI)
0,30
Runoff
689mm/an
PET
522mm
AET
435mm
Mean slope
8,1°
Water table
344cm
Forest
85%
Crops
6%
Urban
4%
Protected
2%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)