f =~ NORMANDEAU City of Nashua
FAAS ASSOCIATES June baee3
ENVIRONMENTAL CONSULTANTS
Study: Instream Habitat and Bypass Flow Assessment
Requestor: NHFGD, NHDES
Requestor Goal & Objectives:
e Determine flow needed to protect aquatic life in the bypassed reach by observation and, if necessary,
by collection of cross sectional data at various transects in the bypassed reach and to determine if the
bypass flows meet NH dissolved oxygen criteria.
e Provide flow regime in bypassed reach that meets the life history requirements of resident fish and
wildlife.
¢ Minimize current and potential negative project operation effects on water quality and aquatic
habitat.
Suggested Approach:
e Implement a Demonstration Flow Assessment (DFA)
o Identify DFA team
o Identify target fish species, lifestages, and habitat suitability criteria (HSC)
© Identify range of bypassed reach assessment flows (~5 flows to help define the flow:habitat
trends}
o Conduct DFA
= Classify mesohabitat types within bypassed reach.
= Place a limited number of transects within bypassed reach to characterize the full
range of habitat availability in bypassed reach.
= Collect representative depth, mean column velocity, substrate and cover at each
transect.
"The product of mesohabitat type HSC for each species/lifestage and proportional
availabity of habitat within the bypassed reach will be compared to calculated
suitability values for all selected DFA flows to determine a meso-scale flow:habitat
relationship.
= The depth, velocity, substrate and/or cover profiles will be compared to the HSC to
determine the total length of each transect that qualifies as “suitable” for each species
and life-stage.
Schedule and Estimated Cost: We suggest identification of target species and bypassed flows are conducted
in consultation with the resource agencies following their review of the PSP and issuance of the RSP.
Consensus on these items should be reached prior to any field sampling which we propose to occur during the
2020 field season (May-October). The estimated cost for the effort as described here is $35,647.00.
Study: Rare, Endangered and Threatened Mussel Survey
Requestor: NHFGD
Requestor Goal & Objectives:
e Survey the Project boundary area to determine the species composition, distribution, and abundance
of freshwater mussels, including the State listed Brook Floater.
