Public Comment. Volume III - Montana Legislature

DRAFT, 4/9/85
(a) quality
(b) forming feature
riffle (ft.)
run (ft.)
substrate
(a boulder (greater than 12 inches 1
(b) cobble (12-2.5 inches 1
(C 1 coarse gravel (2.4-. 5 inches 1
(d) fine gravel (.4-.1 inches)
(el sand
(f clay
stream bank soil alteration rating
stream vegetative stability rating
stream bank undercut and angle
vegetation overhang
embeddedness
Benthic Macroinvertebrates . Quantitative samples
of benthic macroinvertebrates should be collected
immediately upstream and downstream of each proposed
location of disturbance. The collected specimens
should then be counted and identified at
least to genus and to species where possible. The
composition.of the community should be described.
c. Fish Spawning Survey. Several species of game fish
spawn in the Tongue River , including . sauger,
walleye, channel catfish, smallmouth bass, and
sturgeon. A game fish spawning potential survey
should be conducted at each proposed bridge location
as well as areas of proposed extensive
riprapping. Sampling periods for the spawning survey
would be early spring after ice breakup, after
peak runoff, and in the fall. Collection methods
would include electro-shock, seining, trap netting,
and fry sampling.
Mitigation ~echniques. Once sampling has been completed
and detailed data on the aquatic resource to be
affected have been obtained, mitigative measures can be
delineated. Some of the measures that could become
necessary include:
a. Preparation of a construction schedule which provides
for instream work at those times least critical
to the specific fishery or aquatic resource
occurring at a site, as well as the period least
conducive to sediment transport. Such periods
differ by stream and species affected.
-208- Volume Ill: Public Comment