HydroBASINS lev08 watershed · #2080561440
Bassin de l'Avance
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 : Gironde, Lot-et-Garonne
Sub-basin area
440,8km²
Upstream area
440,8km²
Discharge
4,71m³/s
Mean elev.
109m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 0 basins
Source / headwater (no upstream basin)
2 dept-equivalent regions (GADM L2)
- 440.1 km²99.6% of basin
- 1.6 km²0.4% of basin
37 communes (GADM L5)Available for FRA, RWA
- Houeillès36.05 km²54% commune
- Pompogne34.69 km²97% commune
- Pindères31.89 km²76% commune
- Casteljaloux30.89 km²100% commune
- Fargues-sur-Ourbise29.84 km²66% commune
- La Réunion25.41 km²93% commune
- Durance22.40 km²59% commune
- Saint-Martin-Curton21.05 km²51% commune
- Samazan17.21 km²100% commune
- Boussès15.53 km²32% commune
- Beauziac14.86 km²100% commune
- Bouglon13.77 km²100% commune
- Romestaing13.67 km²89% commune
- Poussignac13.09 km²100% commune
- Grézet-Cavagnan12.42 km²100% commune
- Montpouillan12.26 km²100% commune
- Argenton12.25 km²100% commune
- Ruffiac12.17 km²90% commune
- Guérin10.99 km²100% commune
- Labastide-Castel-Amouroux10.00 km²81% commune
- Cocumont9.62 km²38% commune
- Sainte-Marthe8.45 km²85% commune
- Pompiey5.65 km²29% commune
- Marcellus5.07 km²41% commune
- Sainte-Gemme-Martaillac4.67 km²33% commune
- Gaujac3.97 km²55% commune
- Antagnac3.71 km²40% commune
- Fourques-sur-Garonne2.99 km²21% commune
- Sauméjan2.78 km²14% commune
- Marmande1.47 km²3% commune
- Saint-Michel-de-Castelnau1.11 km²3% commune
- Anzex0.92 km²4% commune
- Cours-les-Bains0.41 km²4% commune
- Barbaste0.21 km²1% commune
- Leyritz-Moncassin0.14 km²1% commune
- Caumont-sur-Garonne0.04 km²0% commune
- Grignols0.04 km²0% commune
5 intersecting protected areas
Vallée de l'Avance
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
1.79 km² overlap
Landes De Gascogne
IUCN VRegional Nature Park
1.12 km² overlap
Biotope Protection Order
0.17 km² overlap
La Garonne en Nouvelle-Aquitaine
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.10 km² overlap
Garonne Et Section Du Lot
IUCN IVBiotope Protection Order
0.00 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
3 424 distinct species · 95 237 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 44 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 l'Avance : 32 espèces dont 3 patrimoniales (LR IUCN CR/EN/VU) reliées par 130 interactions GloBI sur 5 types (connectance 13.7%, 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°
12,3°C
Annual rain
867mm
Moisture idx (CMI)
-0,12
Runoff
331mm/an
PET
988mm
AET
684mm
Mean slope
2,0°
Water table
211cm
Forest
59%
Crops
42%
Urban
0%
Protected
0%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)