MBSS Site Summary for: NANJ-151-X-2006


Located on Beaverdam Creek UT1 in the Nanjemoy Creek watershed, 8-digit code: 02140110.
This stream was visited in the spring on 3/28/2006 and again in the summer on 6/14/2006.

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 - 2.3 / 5.0
Benthic IBI Fair - 3.3 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 145 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 5 %
Agricultural Land Use 25 %
Forested Land Use 53 %


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

Physical Stream Habitat
Instream Habitat 8/20 (Marginal)
Epifaunal Substrate 9/20 (Marginal)
Velocity/Depth Diversity 6/20 (Marginal)
Pool Quality
Pool Extent = 51 meters 		11/20 (Suboptimal)
Riffle Quality
Riffle Extent = 0 meters 		0/20 (Poor)
Shading 60 %
Embeddedness 100 %
The embeddedness, a measure of silt on the stream bottom, was 100%. This is very high, and may adversely affect biotic communities.


Stream Water Quality:
Water temperature 18.2 ° C
Dissolved oxygen (DO) 1.8 mg/L
Dissolved oxygen levels measured in the stream were very low (1.8 mg/L). Many fishes and other aquatic animals cannot tolerate low levels of oxygen in the water.
pH (lab) 5.73
Conductivity 62 µmho/cm
Alkalinity
(acid neutralizing capacity) 		66.9 µeq/L
Dissolved organic carbon (DOC) 16.6796 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 4 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Eastern Mudminnow 98
Chain Pickerel 5
Bluegill 1
Golden Shiner 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
American Bullfrog
Eastern Cricket Frog
Gray Treefrog
Marbled Salamander
Northern Green Frog
Red-Spotted Newt
Spotted Salamander

Crayfish:
Cambarus diogenes
Procambarus acutus acutus

Exotic Plants:
No exotic plants noted.
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Polypedilum Non-Biting Midges 33
Hydroporus Water Beetle 14
Caecidotea Isopod 13
Crangonyx Amphipod 8
Bezzia Biting Midge 5
Tanytarsus Non-Biting Midges 5
Kiefferulus 3
Pelocoris 2
Ptilostomis Giant Casemaker Caddisfly 2
Tubificidae Aquatic Worm 2
Ablabesmyia Non-Biting Midge 2
Hydrobaenus Midge 2
Orthocladiinae Midge 1
Nemouridae Nemourid Stonefly 1
Zalutschia Non-Biting Midge 1
Orthocladius Non-Biting Midges 1
Baetidae Small Minnow Mayfly 1
Hesperocorixa 1
Mochlonyx 1
Omisus 1
Limnodrilus 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.