MBSS Site Summary for: PG-N-246-219-97


Located on HENSON CR in the Potomac River U tidal watershed, 8-digit code: 02140201.
This stream was visited in the spring on 3/11/1997 and again in the summer on 6/24/1997.

Index of Biotic Integrity (IBI) Results:

An Index of Biotic Integrity (IBI) is a scientific tool used to identify and classify stream health. An IBI associates anthropogenic influences on a stream or with biological condition in the stream, and is formulated using data developed from biosurveys.
Details on the development and application of MBSS IBIs are in this document.
Fish IBI Good - 4.0 / 5.0
Benthic IBI Poor - 2.4 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 5,021 acres A highly channelized urban stream with concrete banks. An example of a highly channelized urban stream.
Urban Land Use 56.3 %
Agricultural Land Use 12 %
Forested Land Use 27.2 %


Stream showing woody debris, logs, and rocky substrate.
An example of woody debris in a stream.

Physical Stream Habitat
Instream Habitat 9/20 (Marginal)
Epifaunal Substrate 10/20 (Marginal)
Velocity/Depth Diversity 8/20 (Marginal)
Pool Quality
Pool Extent = meters 		8/20 (Marginal)
Riffle Quality 6/20 (Marginal)
Shading 25 %
Embeddedness 30 %


Stream Water Quality:
Water temperature 23 ° C
Dissolved oxygen (DO) 7 mg/L
pH (lab) 7.36
Conductivity 292 µmho/cm
Alkalinity
(acid neutralizing capacity) 		765.3 µeq/L
Dissolved organic carbon (DOC) 3.4 mg/L

Biological Stream Condition:

Surveys of the organisms living within a stream can give indications of stream health. Species richness, or the number of different species present, as well as indicator species (species whose presence, absence or abundance can serve as a measure of environmental conditions) are informative for stream health. 		Close-up of a mayfly indicator species.

Fish Survey Results:
The following 13 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blacknose Dace 200
Swallowtail Shiner 194
Tessellated Darter 43
Satinfin Shiner 20
Redbreast Sunfish 15
American Eel 12
Creek Chub 8
White Sucker 7
Mummichog 5
Creek Chubsucker 3
Rosyside Dace 3
Green Sunfish 2
Eastern Mudminnow 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Two-Lined Salamander

Crayfish:
No crayfish noted.

Exotic Plants:
No exotic plants noted.
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Cricotopus/Orthocladius Midge 20
Rheocricotopus Non-Biting Midges 20
Lumbriculidae Worm 8
Tubificidae Aquatic Worm 6
Cricotopus Non-Biting Midges 4
Eukiefferiella Non-Biting Midges 4
Hydrobaenus Midge 4
Hydropsyche Net-Spinning Caddisfly 2
Polypedilum Non-Biting Midges 2
Hemerodromia Tiny Fly 2
Rheotanytarsus Non-Biting Midges 2
Tanytarsus Non-Biting Midges 1
Collembola Springtail 1
Nanocladius Non-Biting Midges 1
Cheumatopsyche Net-Spinning Caddisfly 1
Physa Air-Breathing Freshwater Snail 1
Naididae Aquatic Worm 1
Kick net sampling for macroinvertebrates.
Sampling with a kick net.

Information disclaimer: The information and data on this page is for guidance and general planning purposes only. It should not be used to make decisions on specific matters.