HydroBASINS lev08 watershed · #7080041170
Bassin de Severn Run
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 3 administrative regions : Anne Arundel, Baltimore, Calvert
Sub-basin area
1 286,6km²
Upstream area
1 286,6km²
Discharge
3,39m³/s
Mean elev.
24m
Administrative coverage
3 dept-equivalent regions (GADM L2)
- 714.3 km²55.5% of basin
- 445.8 km²34.6% of basin
- 15.7 km²1.2% of basin
30 intersecting protected areas
Severn Run
IUCN VNatural Environment Area
7.46 km² overlap
Parker Creek
IUCN VHeritage Conservation
7.22 km² overlap
Calvert Cliffs
IUCN IIIState Park
5.32 km² overlap
Cove Point
IUCN VEasement
4.05 km² overlap
Local Conservation Area
1.41 km² overlap
Flag Ponds
IUCN IIIPond
1.20 km² overlap
Gravatt 1C
IUCN VPrivate Conservation
0.68 km² overlap
Research Center
0.49 km² overlap
Farms At Hunting Creek
IUCN Not AssignedConservation Easement
0.49 km² overlap
21 more protected areassorted by overlap area
Maryland Environmental Trust Easement #11
IUCN Not AssignedEasement
0.46 km² overlap
Private Conservation Land
0.42 km² overlap
Maryland Environmental Trust Easement #84
IUCN Not AssignedEasement
0.39 km² overlap
Lake Waterford
IUCN IIIPark
0.34 km² overlap
Bacon Ridge
IUCN IIINatural Area
0.28 km² overlap
Hellen Creek Fee
IUCN VPrivate Conservation Land
0.28 km² overlap
Parkers Creek
IUCN VPCL
0.26 km² overlap
Maryland Environmental Trust Easement #23
IUCN Not AssignedEasement
0.26 km² overlap
Maryland Environmental Trust Easement #10
IUCN Not AssignedEasement
0.20 km² overlap
Brewers Pond
IUCN VNatural Area
0.19 km² overlap
Eagles Trace
IUCN Not AssignedConservation Easement
0.16 km² overlap
Hallowing Point District Park And The Property Of Guy H Hall
IUCN Not AssignedPark
0.08 km² overlap
Maryland Environmental Trust Easement #44
IUCN Not AssignedEasement
0.07 km² overlap
DNR
IUCN Not AssignedConservation Easement
0.06 km² overlap
Oakland Hall Subdiviision
IUCN Not AssignedConservation Easement
0.01 km² overlap
Brighton Woods
IUCN Not AssignedConservation Easement
0.01 km² overlap
Maryland Environmental Trust Easement #0
IUCN Not AssignedEasement
0.01 km² overlap
Donas & Virginia Mccready Fra Site
IUCN Not AssignedConservation Easement
0.01 km² overlap
Prout Property
IUCN Not AssignedConservation Easement
0.01 km² overlap
The Property Of Huntingtown Mediical
IUCN Not AssignedConservation Easement
0.00 km² overlap
Bethel Way Of The Cross Church Of Christ
IUCN Not AssignedConservation Easement
0.00 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
7 157 distinct species · 1 948 109 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 36 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 Severn Run : 27 espèces dont 1 patrimoniale (LR IUCN CR/EN/VU) reliées par 69 interactions GloBI sur 3 types (connectance 10.4%, filtre Serrano α=0.2). 10 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°
13,3°C
Annual rain
1 079mm
Moisture idx (CMI)
-0,02
Runoff
506mm/an
PET
1 103mm
AET
845mm
Mean slope
1,5°
Water table
86cm
Forest
85%
Crops
10%
Urban
31%
Protected
7%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)