MBSS Site Summary for: PG-N-125-218-97


Located on BEAVERDAM CR in the Anacostia River watershed, 8-digit code: 02140205.
This stream was visited in the spring on 3/12/1997 and again in the summer on 6/18/1997.

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 Fair - 3.0 / 5.0
Benthic IBI Poor - 2.7 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 5,017 acres A highly channelized urban stream with concrete banks. An example of a highly channelized urban stream.
Urban Land Use 68.4 %
Agricultural Land Use 12 %
Forested Land Use 17.4 %


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

Physical Stream Habitat
Instream Habitat 16/20 (Optimal)
Epifaunal Substrate 3/20 (Poor)
Velocity/Depth Diversity 12/20 (Suboptimal)
Pool Quality
Pool Extent = meters 		16/20 (Optimal)
Riffle Quality 5/20 (Poor)
Shading 80 %
Embeddedness 65 %
The embeddedness, a measure of silt on the stream bottom, was 65%. This is relatively high, and may exclude some biota.


Stream Water Quality:
Water temperature 20 ° C
Dissolved oxygen (DO) 7.5 mg/L
pH (lab) 7.3
Conductivity 350 µmho/cm
Alkalinity
(acid neutralizing capacity) 		1341 µeq/L
Dissolved organic carbon (DOC) 4.5 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 11 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Redbreast Sunfish 41
Green Sunfish 36
Mummichog 21
Satinfin Shiner 21
Swallowtail Shiner 13
Golden Shiner 9
Blacknose Dace 7
Banded Killifish 4
American Eel 2
White Sucker 2
Tessellated Darter 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
No amphibians and reptiles noted.

Crayfish:
Orconectes limosus

Exotic Plants:
No exotic plants noted.
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Conchapelopia Non-Biting Midges 44
Cricotopus/Orthocladius Midge 10
Lumbriculidae Worm 8
Limnodrilus Worm 4
Argia Narrow-Winged Damselfly 4
Ischnura 3
Nanocladius Non-Biting Midges 2
Hemerodromia Tiny Fly 2
Coenagrionidae Narrowwinged Damselfly 2
Phaenopsectra Non-Biting Midges 1
Collembola Springtail 1
Procloeon 1
Physa Air-Breathing Freshwater Snail 1
Calopteryx Damselfly 1
Cura Flatworm 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.