HydroBASINS lev08 watershed · #2080049720
Bassin de Rhymney River
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 9 administrative regions : Caerphilly, Cardiff, NA, Newport, Powys +1
Sub-basin area
500,5km²
Upstream area
500,5km²
Discharge
0,03m³/s
Mean elev.
223m
Administrative coverage
9 dept-equivalent regions (GADM L2)
- Caerphilly232.8 km²46.3% of basin
- NA102.1 km²20.3% of basin
- Newport62.7 km²12.5% of basin
- Cardiff56.9 km²11.3% of basin
- NA25.4 km²5.1% of basin
- Powys16.3 km²3.2% of basin
- NA0.8 km²0.2% of basin
- 0.4 km²0.1% of basin
1 moreFull L2 list
- NA0.0 km² · 0.0%
30 intersecting protected areas
Bannau Brycheiniog
IUCN VNational Park
16.32 km² overlap
Gwent Levels - St. Brides
IUCN IVSite of Special Scientific Interest
13.07 km² overlap
Site of Special Scientific Interest
9.77 km² overlap
Severn Estuary
IUCN IVSite of Special Scientific Interest
6.75 km² overlap
Severn Estuary/ Môr Hafren
IUCN Not ReportedEmerald Network
6.68 km² overlap
Severn Estuary
IUCN IVWetland of International Importance (Ramsar Site)
6.43 km² overlap
Severn Estuary
IUCN Not ReportedEmerald Network
6.42 km² overlap
Mynydd Llangynidr
IUCN IVSite of Special Scientific Interest
5.97 km² overlap
Severn Estuary / Môr Hafren
IUCN Not ReportedMarine Protected Area (OSPAR)
5.26 km² overlap
21 more protected areassorted by overlap area
Severn Estuary
IUCN Not ReportedMarine Protected Area (OSPAR)
5.06 km² overlap
Site of Special Scientific Interest
3.29 km² overlap
Usk Bat Sites/ Safleoedd Ystlumod Wysg
IUCN Not ReportedEmerald Network
3.29 km² overlap
Parc Bryn Bach
IUCN Not ReportedLocal Nature Reserve
1.12 km² overlap
Beaufort Hills Pond And Woodland
IUCN Not ReportedLocal Nature Reserve
0.82 km² overlap
Sirhowy Hill Woodlands And Cardiff Pond
IUCN Not ReportedLocal Nature Reserve
0.74 km² overlap
Ruperra Castle & Woodlands
IUCN IVSite of Special Scientific Interest
0.63 km² overlap
Silent Valley
IUCN Not ReportedLocal Nature Reserve
0.52 km² overlap
Cefn Y Brithdir
IUCN IVSite of Special Scientific Interest
0.48 km² overlap
Aberbargoed Grasslands
IUCN IVSite of Special Scientific Interest
0.43 km² overlap
National Nature Reserve
0.42 km² overlap
Aberbargoed Grasslands
IUCN Not ReportedEmerald Network
0.40 km² overlap
Site of Special Scientific Interest
0.30 km² overlap
Gwaun Gledyr
IUCN IVSite of Special Scientific Interest
0.28 km² overlap
River Usk/ Afon Wysg
IUCN Not ReportedEmerald Network
0.28 km² overlap
Cwm Merddog Woodlands
IUCN IVSite of Special Scientific Interest
0.23 km² overlap
Parc Nant-Y-Waun
IUCN Not ReportedLocal Nature Reserve
0.21 km² overlap
Nant Fawr Corridor
IUCN Not ReportedLocal Nature Reserve
0.20 km² overlap
Roseheyworth
IUCN Not ReportedLocal Nature Reserve
0.15 km² overlap
Graig Goch
IUCN Not ReportedLocal Nature Reserve
0.14 km² overlap
Cardiff Bay Wetlands And Hamadryad Park
IUCN Not ReportedLocal Nature Reserve
0.12 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
8 762 distinct species · 669 275 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 35 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 Rhymney River : 22 espèces dont 1 patrimoniale (LR IUCN CR/EN/VU) reliées par 108 interactions GloBI sur 6 types (connectance 18.2%, filtre Serrano α=0.2). 13 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°
9,0°C
Annual rain
1 141mm
Moisture idx (CMI)
0,44
Runoff
848mm/an
PET
631mm
AET
553mm
Mean slope
6,4°
Water table
310cm
Forest
2%
Crops
14%
Urban
45%
Protected
11%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)