HydroBASINS lev08 watershed · #2080446580
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, Yvelines
Sub-basin area
557,8km²
Upstream area
64 635,6km²
Discharge
446,01m³/s
Mean elev.
98m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 2 basins
- Bassin de l'Epte1480 km²
- Bassin de la Seine225 km²
2 dept-equivalent regions (GADM L2)
- 545.8 km²97.5% of basin
- 13.8 km²2.5% of basin
89 communes (GADM L5)Available for FRA, RWA
- Les Andelys40.05 km²100% commune
- Vernon34.60 km²100% commune
- Hennezis15.54 km²100% commune
- Venables15.33 km²100% commune
- Muids14.86 km²100% commune
- Tosny14.68 km²100% commune
- Harquency14.13 km²100% commune
- Bouafles12.98 km²100% commune
- Saint-Aubin-sur-Gaillon12.28 km²64% commune
- Notre-Dame-de-l'Isle12.11 km²100% commune
- Mézières-en-Vexin12.06 km²94% commune
- Port-Mort11.97 km²100% commune
- Daubeuf-près-Vatteville11.11 km²100% commune
- Guiseniers10.83 km²100% commune
- Forêt-la-Folie10.78 km²100% commune
- Fresne-l'Archevêque10.53 km²100% commune
- Gaillon10.51 km²100% commune
- Saint-Marcel10.32 km²100% commune
- Pressagny-l'Orgueilleux10.17 km²100% commune
- Blaru9.96 km²66% commune
- Tilly9.02 km²72% commune
- Saint-Pierre-la-Garenne8.01 km²100% commune
- Panilleuse7.94 km²94% commune
- Aubevoye7.91 km²100% commune
- Écouis7.89 km²60% commune
- La Chapelle-Réanville7.88 km²98% commune
- Guitry7.71 km²100% commune
- Ailly7.38 km²47% commune
- Heuqueville7.34 km²95% commune
- Saint-Pierre-d'Autils6.76 km²100% commune
- Bernières-sur-Seine6.47 km²100% commune
- Saint-Pierre-de-Bailleul6.39 km²98% commune
- Cuverville6.27 km²100% commune
- La Roquette6.22 km²100% commune
- Bois-Jérôme-Saint-Ouen6.20 km²61% commune
- Fontenay6.12 km²88% commune
- Amfreville-sous-les-Monts6.12 km²85% commune
- Boisemont6.05 km²45% commune
- Cahaignes5.92 km²63% commune
- Tourny5.79 km²47% commune
- Houville-en-Vexin5.64 km²67% commune
- Courcelles-sur-Seine5.50 km²100% commune
- Andé5.24 km²100% commune
- Heudebouville5.22 km²57% commune
- Corny5.01 km²100% commune
- Saint-Étienne-sous-Bailleul4.59 km²100% commune
- Fontaine-Bellenger4.56 km²84% commune
- Saint-Just4.46 km²100% commune
- Vatteville4.39 km²100% commune
- Villers-sur-le-Roule4.35 km²100% commune
- Sainte-Barbe-sur-Gaillon4.14 km²100% commune
- Villez-sous-Bailleul4.07 km²94% commune
- Richeville4.05 km²100% commune
- Suzay4.04 km²100% commune
- Mouflaines4.02 km²100% commune
- Connelles3.99 km²100% commune
- Herqueville3.77 km²100% commune
- Saint-Pierre-du-Vauvray3.50 km²78% commune
- Mercey3.44 km²100% commune
- Le Thuit3.09 km²100% commune
- Giverny2.98 km²46% commune
- Port-Villez2.95 km²54% commune
- Porte-Joie2.86 km²84% commune
- Val-de-Reuil2.80 km²10% commune
- Vieux-Villez2.70 km²100% commune
- Cantiers2.54 km²100% commune
- Heubécourt-Haricourt2.23 km²18% commune
- Villers-en-Vexin2.03 km²31% commune
- Tournedos-sur-Seine2.01 km²68% commune
- Vézillon1.96 km²100% commune
- Poses1.95 km²36% commune
- Vironvay1.94 km²48% commune
- Authevernes1.29 km²16% commune
- Saint-Étienne-du-Vauvray0.90 km²50% commune
- Saint-Julien-de-la-Liègue0.88 km²19% commune
- Douains0.88 km²8% commune
- Flipou0.77 km²11% commune
- Saint-Vincent-des-Bois0.74 km²14% commune
- La Heunière0.66 km²24% commune
- Farceaux0.61 km²8% commune
- Houlbec-Cocherel0.58 km²5% commune
- Limetz-Villez0.50 km²5% commune
- Chaufour-lès-Bonnières0.43 km²14% commune
- Hacqueville0.39 km²4% commune
- Sainte-Marie-de-Vatimesnil0.32 km²5% commune
- Bacqueville0.22 km²2% commune
- Les Thilliers-en-Vexin0.16 km²11% commune
- Sainte-Colombe-près-Vernon0.04 km²1% commune
- La Croix-Saint-Leufroy0.01 km²0% commune
16 intersecting protected areas
Terrasses alluviales de la Seine
IUCN Not ReportedSpecial Protection Area (Birds Directive)
24.60 km² overlap
Boucles de la Seine Amont d'Amfreville à Gaillon
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
18.79 km² overlap
Iles et berges de la Seine dans l'Eure
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
2.66 km² overlap
Les grottes du mont Roberge
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.94 km² overlap
Vallée de l'Epte
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.77 km² overlap
Land acquired by a regional conservatory of natural areas
0.75 km² overlap
Vallée de l'Epte francilienne et ses affluents
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.43 km² overlap
le chemin
IUCN IVLand acquired by a regional conservatory of natural areas
0.38 km² overlap
Land acquired by a regional conservatory of natural areas
0.34 km² overlap
7 more protected areassorted by overlap area
Coteaux et boucles de la seine
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.24 km² overlap
la cote saint-jacques
IUCN IVLand acquired by a regional conservatory of natural areas
0.13 km² overlap
les falaises de connelles
IUCN IVLand acquired by a regional conservatory of natural areas
0.10 km² overlap
Land acquired by a regional conservatory of natural areas
0.08 km² overlap
la cote de la roque
IUCN IVLand acquired by a regional conservatory of natural areas
0.08 km² overlap
l\'hippodrome
IUCN IVLand acquired by a regional conservatory of natural areas
0.04 km² overlap
La Carrière Du Plessis
IUCN IVBiotope Protection Order
0.00 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
4 312 distinct species · 165 228 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 de la Seine : 32 espèces reliées par 113 interactions GloBI sur 5 types (connectance 16.1%, filtre Serrano α=0.2). 6 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°
10,3°C
Annual rain
643mm
Moisture idx (CMI)
-0,18
Runoff
388mm/an
PET
788mm
AET
535mm
Mean slope
2,7°
Water table
202cm
Forest
5%
Crops
47%
Urban
10%
Protected
0%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)