MBSS Site Summary for: COCA-119-N-2004


Located on POTOMAC R UT 14 in the Potomac River WA Cnty watershed, 8-digit code: 02140501.
This stream was visited in the spring on 4/22/2004 and again in the summer on 7/8/2004.

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 Poor - 1.3 / 5.0
Benthic IBI Poor - 1.5 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 604 acres Cows standing in a stream at a site with high agricultural land use. Cows survey the sampling procedure at this extreme example of a highly agriculturalized site.
Urban Land Use 6 %
Agricultural Land Use 48 %
Forested Land Use 45 %


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

Physical Stream Habitat
Instream Habitat 7/20 (Marginal)
Epifaunal Substrate 6/20 (Marginal)
Velocity/Depth Diversity 7/20 (Marginal)
Pool Quality
Pool Extent = 26 meters 		6/20 (Marginal)
Riffle Quality
Riffle Extent = 55 meters 		6/20 (Marginal)
Shading 90 %
Embeddedness 85 %
The embeddedness, a measure of silt on the stream bottom, was 85%. This is relatively high, and may exclude some biota.


Stream Water Quality:
Water temperature 20.6 ° C
Dissolved oxygen (DO) 6.9 mg/L
pH (lab) 7.41
Conductivity 336 µmho/cm
Alkalinity
(acid neutralizing capacity) 		1285 µeq/L
Dissolved organic carbon (DOC) 3.5 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 2 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Green Sunfish 6
Fallfish 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
No amphibians and reptiles noted.

Crayfish:
No crayfish noted.

Exotic Plants:
Japanese Stiltgrass
Multiflora Rose
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Caecidotea Isopod 64
Orthocladius Non-Biting Midges 27
Gammarus Amphipod 19
Amphinemura Spring Stonefly 4
Corynoneura Non-Biting Midges 4
Natarsia Non-Biting Midges 1
Orthocladiinae Midge 1
Limnophyes Non-Biting Midge 1
Dytiscidae Predaceous Diving Beetle 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.