Environmental Engineering Reference
In-Depth Information
The chemical parameters selected for rapid bioassessments are usually those that can be mea-
sured quickly in the ield, such as by using probes. Examples include temperature, speciic con-
ductance, dissolved oxygen, pH, and turbidity. Other water quality indicators, such as odors or the
presence of surface oils or deposits, are usually determined by visual inspection.
A variety of groups of biota may be used for rapid bioassessments, such as assemblages of ish,
periphyton, and macroinvertebrates, with perhaps macroinvertebrates being most commonly used.
Location
Stream class
River basin
Agency
Stream name
Station #
Rivermile
Lat
Storet #
Investigators
Long
Date Reason for survey
Time PM
Form completed by
AM
Habitat
parameter
Condition category
Optimal
Suboptimal
Marginal
Poor
30%-50% mix of stable
habitat; well-suited for
full colonization potential;
adequate habitat for
maintenance of
populations; presence of
additional substrate in the
form of newfall, but not
yet prepared for
colonization (may rate at
high end of scale).
10%-30% mix of stable
habitat; habitat
availability less than
desirable; substrate
frequently disturbed or
removed.
Greater than 50% of
substrate favorable for
epifaunal colonization and
fish cover; mix of snags,
submerged logs, undercut
banks, cobble or other
stable habitat and at stage
to allow full colonization
potential (i.e., logs/snags
that are not new fall and
not transient).
Less than 10% stable
habitat; lack of habitat is
obvious; substrate
unstable or lacking.
1. Epifaunal
substrate/
available cover
Score
20
19
18
17
16
15
14
13
12
11
10 9876543210
Mixture of substrate
materials, with gravel and
firm sand prevalent; root
mats and submerged
vegetation common.
Mixture of soft sand, mud,
or clay; mud may be
dominant; some root mats
and submerged vegetation
present.
All mud or clay or sand
bottom; little or no root
mat; no submerged
vegetation.
Hard-pan clay or bedrock;
no root mat or vegetation
2. Pool substrate
characterization
Score
20
19
18
17
16
15
14
13
12
11
10 9876543210
Even mix of large-
shallow, large-deep,
small-shallow, small-deep
pools present.
Majority of pools large-
deep; very few shallow.
Shallow pools much more
prevalent than deep pools.
Majority of pools small-
shallow or pools absent.
3. Pool variability
Score
20
19
18
17
16
15
14
13
12
11
10
9
8 76543210
Little or no enlargement
of islands or point bars
and less than <20% of the
bottom affected by
sediment deposition.
Some new increase in bar
formation, mostly from
gravel, sand or fine
sediment; 20%-50% of the
bottom affected; slight
deposition in pools.
Moderate deposition of
new gravel, sand or fine
sediment on old and new
bars; 50%-80% of the
bottom affected; sediment
deposits at obstructions,
constrictions, and bends;
moderate deposition of
pools prevalent.
Heavy deposits of fine
material, increased bar
development; more than
80% of the bottom
changing frequently; pools
almost absent due to
substantial sediment
deposition.
4. Sediment
deposition
Score
20
19
18
17
16
15
14
13
12
11
10
9
8 76543210
Water reaches base of
both lower banks, and
minimal amount of
channel substrate is
exposed.
Water fills >75% of the
available channel; or
<25% of channel substrate
is exposed.
Water fills 25%-75% of the
available channel, and/or
ri¡e substrates are mostly
exposed.
Very little water in
channel and mostly
present as standing pools.
5. Channel flow
status
Score
20
19
18
17
16
15
14
13
12
11
10 9876543210
FIGURE 7.5 Example of a rapid bioassessment ield data sheet for habitat (front page), for low gradi-
ent streams. (From Barbour, M.T., Gerritsen, J., Snyder, B.D., and Stribling, J.B., Rapid Bioassessment
Protocols for Use in Streams and Wadeable Rivers: Periphyton, Benthic Macroinvertebrates and Fish , U.S.
Environmental Protection Agency, Ofice of Water, Washington, DC, 1999.)
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