HydroBASINS lev08 watershed · #2080446440
Bassin de la Seine
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 2 administrative regions : Eure, Seine-Maritime
Sub-basin area
22,1km²
Upstream area
65 387,8km²
Discharge
457,43m³/s
Mean elev.
19m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 2 basins
- Bassin de l'Andelle730 km²
- Bassin de la Seine558 km²
2 dept-equivalent regions (GADM L2)
- 21.9 km²98.7% of basin
- 0.3 km²1.3% of basin
14 communes (GADM L5)Available for FRA, RWA
- Val-de-Reuil6.27 km²23% commune
- Pîtres3.73 km²33% commune
- Poses3.44 km²64% commune
- Alizay2.79 km²33% commune
- Le Manoir2.54 km²98% commune
- Tournedos-sur-Seine0.93 km²32% commune
- Léry0.68 km²8% commune
- Porte-Joie0.56 km²16% commune
- Amfreville-sous-les-Monts0.50 km²7% commune
- Le Vaudreuil0.45 km²9% commune
- Quévreville-la-Poterie0.24 km²5% commune
- Ymare0.04 km²1% commune
- Romilly-sur-Andelle0.00 km²0% commune
- Les Damps0.00 km²0% commune
3 intersecting protected areas
Terrasses alluviales de la Seine
IUCN Not ReportedSpecial Protection Area (Birds Directive)
9.13 km² overlap
Boucles de la Seine Amont d'Amfreville à Gaillon
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.39 km² overlap
Iles et berges de la Seine dans l'Eure
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.17 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
1 674 distinct species · 41 210 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 37 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 la Seine : 27 espèces dont 2 patrimoniales (LR IUCN CR/EN/VU) reliées par 89 interactions GloBI sur 4 types (connectance 12.7%, filtre Serrano α=0.2). 11 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°
10,8°C
Annual rain
640mm
Moisture idx (CMI)
-0,20
Runoff
476mm/an
PET
805mm
AET
536mm
Mean slope
0,9°
Water table
54cm
Forest
13%
Crops
35%
Urban
32%
Protected
0%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)