MBSS Site Summary for: EVIT-108-R-2004


Located on WILLOW BROOK in the Evitts Creek watershed, 8-digit code: 02141002.
This stream was visited in the spring on 3/4/2004 and again in the summer on 7/21/2004.

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 - 2.0 / 5.0
Benthic IBI Poor - 1.5 / 5.0

Land Use

Land use can provide important information for determining stream health.
(Hint: Screen readers will announce definitions; mouse users can hover over dotted text.)
Catchment area 733 acres A highly channelized urban stream with concrete banks. An example of a highly channelized urban stream.
Urban Land Use 45 %
Agricultural Land Use 9 %
Forested Land Use 46 %


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

Physical Stream Habitat
Instream Habitat 10/20 (Marginal)
Epifaunal Substrate 12/20 (Suboptimal)
Velocity/Depth Diversity 6/20 (Marginal)
Pool Quality
Pool Extent = 41 meters 		7/20 (Marginal)
Riffle Quality
Riffle Extent = 45 meters 		7/20 (Marginal)
Shading 95 %
Embeddedness 40 %


Stream Water Quality:
Water temperature 18.5 ° C
Dissolved oxygen (DO) 8.1 mg/L
pH (lab) 8.33
Conductivity 871 µmho/cm
Alkalinity
(acid neutralizing capacity) 		1054 µeq/L
Dissolved organic carbon (DOC) 1.8 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
Blacknose Dace 68
Creek Chub 49
Potomac Sculpin 12
Fantail Darter 7
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Green Frog
Northern Two-Lined Salamander

Crayfish:
No crayfish noted.

Exotic Plants:
Japanese Honeysuckle
Multiflora Rose
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Orthocladius Non-Biting Midges 34
Sympotthastia Non-Biting Midges 12
Parametriocnemus Non-Biting Midges 11
Thienemannimyia group Non-Biting Midges 10
Diamesa Bloodworm 8
Chimarra Fingernet Caddisfly 7
Orthocladiinae Midge 4
Tvetenia Non-Biting Midges 2
Hydropsyche Net-Spinning Caddisfly 2
Diplocladius Non-Biting Midges 2
Micropsectra Non-Biting Midges 1
Paratanytarsus Non-Biting Midges 1
Psephenus Water Penny 1
Tanytarsini Non-Biting Midges 1
Cheumatopsyche Net-Spinning Caddisfly 1
Calopteryx Damselfly 1
Rhyacophila Free-Living Caddisfly 1
Caecidotea Isopod 1
Dolichopodidae Long-Legged Fly 1
Simulium Black Fly 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.