HydroBASINS lev08 watershed · #1081598220
Bassin de Riet
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 : Bojanala, City of Johannesburg, City of Tshwane, Ekurhuleni
Sub-basin area
1 066,9km²
Upstream area
1 066,9km²
Discharge
0,9m³/s
Mean elev.
1 535m
Administrative coverage
Hydrographic chain
▼ Drains into
▲ Receives from 0 basins
Source / headwater (no upstream basin)
4 dept-equivalent regions (GADM L2)
- City of Tshwane501.5 km²47.1% of basin
- Ekurhuleni500.5 km²47.0% of basin
- City of Johannesburg62.5 km²5.9% of basin
- 0.3 km²0.0% of basin
6 intersecting protected areas
Rietvlei Nature Reserve
IUCN Not ReportedNature Reserve
45.47 km² overlap
Van Riebeeck Nature Reserve
IUCN Not ReportedNature Reserve
38.85 km² overlap
Crocodile River Reserve Central Nature Reserve Cluster
IUCN Not ReportedNature Reserve
4.52 km² overlap
Crocodile River Reserve Protected Environment
IUCN Not ReportedProtected Environment
4.38 km² overlap
Crocodile River Reserve Doornrandje Nature Reserve Cluster
IUCN Not ReportedNature Reserve
2.19 km² overlap
Glen Austinpan Bird Sanctuary
IUCN Not ReportedNature Reserve
0.10 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
3 592 distinct species · 740 587 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 24 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 Riet : 23 espèces reliées par 17 interactions GloBI sur 3 types (connectance 6.2%, filtre Serrano α=0.2). 1 bulle taxonomique (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°
16,4°C
Annual rain
710mm
Moisture idx (CMI)
-0,51
Runoff
35mm/an
PET
1 457mm
AET
601mm
Mean slope
2,2°
Water table
537cm
Forest
4%
Crops
18%
Urban
45%
Protected
3%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)