HydroBASINS lev08 watershed · #2080021290
Bassin du Val
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 1 administrative regions : Finistère
Sub-basin area
270,9km²
Upstream area
271,4km²
Discharge
7,28m³/s
Mean elev.
47m
Administrative coverage
13 communes (GADM L5)Available for FRA, RWA
- Trégunc51.05 km²100% commune
- Melgven44.91 km²87% commune
- Concarneau42.03 km²100% commune
- Fouesnant34.99 km²99% commune
- La Forêt-Fouesnant19.27 km²100% commune
- Névez19.10 km²72% commune
- Saint-Yvi11.38 km²41% commune
- Bénodet9.85 km²94% commune
- Clohars-Fouesnant5.61 km²42% commune
- Pleuven5.26 km²38% commune
- Pont-Aven5.24 km²18% commune
- Rosporden2.88 km²5% commune
- Saint-Évarzec1.56 km²6% commune
20 intersecting protected areas
Dunes et côtes de Trévignon
IUCN Not ReportedSpecial Protection Area (Birds Directive)
11.70 km² overlap
Dunes et côtes de Trévignon
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
11.70 km² overlap
Archipel de Glenan
IUCN Not ReportedSpecial Protection Area (Birds Directive)
11.38 km² overlap
Archipel des Glénan
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
10.75 km² overlap
Archipel des Glénan
IUCN Not ReportedMarine Protected Area (OSPAR)
10.71 km² overlap
Marais de Mousterlin
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
3.97 km² overlap
Dunes et etangs de kerouiny
IUCN IVLand acquired by Conservatoire du Littoral (national seaside and lakeside conservancy)
2.39 km² overlap
Marais de mousterlin
IUCN IVLand acquired by Conservatoire du Littoral (national seaside and lakeside conservancy)
1.13 km² overlap
Anse saint laurent
IUCN IVLand acquired by Conservatoire du Littoral (national seaside and lakeside conservancy)
0.35 km² overlap
11 more protected areassorted by overlap area
Archipel des glenan
IUCN IVLand acquired by Conservatoire du Littoral (national seaside and lakeside conservancy)
0.30 km² overlap
Penfoulic
IUCN IVLand acquired by Conservatoire du Littoral (national seaside and lakeside conservancy)
0.30 km² overlap
Biotope Protection Order
0.18 km² overlap
Anse de pouldohan
IUCN IVLand acquired by Conservatoire du Littoral (national seaside and lakeside conservancy)
0.14 km² overlap
Protected perimeter around a national nature reserve
0.12 km² overlap
Raguenes
IUCN IVLand acquired by Conservatoire du Littoral (national seaside and lakeside conservancy)
0.06 km² overlap
Ile Aux Moutons (Moelez)
IUCN IVBiotope Protection Order
0.04 km² overlap
Roches de Penmarch
IUCN Not ReportedMarine Protected Area (OSPAR)
0.02 km² overlap
Roches de Penmarc'h
IUCN Not ReportedSpecial Protection Area (Birds Directive)
0.02 km² overlap
Roches de Penmarch
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.02 km² overlap
Saint-Nicolas-Des-Glénan
IUCN IVNational Nature Reserve
0.02 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
3 222 distinct species · 88 281 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 38 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 du Val : 24 espèces reliées par 84 interactions GloBI sur 6 types (connectance 11.3%, filtre Serrano α=0.2). 15 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°
11,4°C
Annual rain
1 024mm
Moisture idx (CMI)
0,33
Runoff
840mm/an
PET
689mm
AET
565mm
Mean slope
1,6°
Water table
101cm
Forest
9%
Crops
33%
Urban
14%
Protected
2%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)