HydroBASINS lev08 watershed · #7080500890
Bassin de Walnut Creek
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 4 administrative regions : Dallas, Madison, Polk, Warren
Sub-basin area
469,5km²
Upstream area
9 317,7km²
Discharge
55,05m³/s
Mean elev.
287m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 2 basins
4 dept-equivalent regions (GADM L2)
- DallasIowa · United States273.1 km²58.1% of basin
- PolkIowa · United States183.0 km²38.9% of basin
- MadisonIowa · United States11.7 km²2.5% of basin
- WarrenIowa · United States2.5 km²0.5% of basin
2 intersecting protected areas
Reserve Program
0.06 km² overlap
Alice's Road
IUCN VGreenbelt Park
0.06 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
1 523 distinct species · 238 007 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 Walnut Creek : 30 espèces reliées par 84 interactions GloBI sur 3 types (connectance 11.9%, filtre Serrano α=0.2). 8 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°
9,4°C
Annual rain
837mm
Moisture idx (CMI)
-0,19
Runoff
206mm/an
PET
1 029mm
AET
710mm
Mean slope
1,4°
Water table
152cm
Forest
4%
Crops
53%
Urban
33%
Protected
0%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)