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SEFA pathways. New environmental flow analysis package developed with Normandeau support


SEFA pathways. Custom-variable time series event analysis
Normandeau Associates' Instream Flow team has been involved in all phases of applying and reviewing Instream Flow Incremental Methodology studies, from project impact scoping, assessment method selection, and flow study performance, to computer analysis using using U.S. Fish and Wildlife Service's (USFWS) PHABSIM (Physical Habitat Simulation System), results negotiation and interpretation, and final project mitigation design. Our staff has extensive experience designing and conducting habitat suitability criteria studies for a wide variety of aquatic species.

Our Instream Flow team also offers training, workshops, and university classes in the application of PHABSIM with software developed by our staff. This software, called RHABSIM (Riverine HABitat SIMuation), is a fully integrated program for river hydraulics and aquatic habitat modeling using the Instream Flow Incremental Methodology. Running in Microsoft Windows and DOS, it is an extensive conversion of the USFWS PHABSIM hydraulic and habitat simulation system.

Our Services Include

Habitat Criteria Development: Habitat Suitability Criteria (HSC) are an integral component of instream flow modeling using PHABSIM, 2D models, or other habitat-based modeling approaches. Despite the direct and significant effects of HSC on estimating the flow-habitat relationship, relatively little guidance is available to assist flow modelers in the development and/or evaluation of HSC. Consequently, the old adage of "garbage-in, garbage-out" is a real possibility. Normandeau staff has been involved with the development of site-specific HSC curves for 25 species in over 60 rivers within the U.S., Canada, and the tropical Pacific. Projects have occurred in small headwater streams, large mainstem rivers, and remote tropical streams, involving a diverse assemblage of warmwater, coldwater, anadromous, and resident fish species in summer and winter conditions. This breadth of experience from collecting new HSC data, testing transferability of existing HSC, and conducting fish counts makes Normandeau a leader in studies involving snorkeling and scuba methodologies.

Water Temperature Modeling: Normandeau staff has experience applying the Stream Network Temperature Model in network and individual laptop/tablet versions, from project scoping, data collection and temperature study performance, to computer analysis, calibration, simulation, gaming and results interpretation and negotiation. Normandeau staff has devloped its own stream temperature modeling software. StreamTemp: A Simple Network Stream Temperature Model for Windows is a stream temperature model for predicting changes in water temperature from upstream modifications in flow. Running on Microsoft Windows, it is a full extension of the SSSOLAR, SSSHADE and SSTEMP models developed by the U. S. Fish and Wildlife Service.

Acoustic Doppler Flow Measurements (ADCP): We have extensive experience conducting ADCP measurements for discharge and IFIM data collection in many rivers. Our staff has also developed a mobile tether system for data collection in remote locations where no boat access exists and wading is not an option. ADCP data allows for economical collection of the high volume field data required in many of today's rigorous Instream Flow Studies. Our staff has also developed a software program for importing ADCP data into RHABSIM.

Fishery Evaluations: Fish habitat quality and utilization surveys, fish population estimates, spawning ground surveys, creel survey studies, fish age and growth studies, and project impact analyses have all been conducted by our staff to evaluate potential impacts of existing and proposed development projects.

Aquatic Invertebrate Investigations: We have conducted a variety of aquatic invertebrate abundance and diversity studies in both freshwater and marine environments. Our staff has been trained in the current rapid bioassessment techniques, including the California Aquatic Bioassessment Methodology.

Hydrologic and Sediment Analysis: In addition to routinely incorporating hydrologic analyses into instream flow studies and habitat studies, we have evaluated sediment transport and deposition both within stream systems and on deltas formed at the confluence of small tributaries and major rivers.

Licensing Document Preparation: We have prepared fisheries sections of licensing and re-licensing documents such as environmental impact assessments, applications to FERC, and special use permits to satisfy regulatory requirements.

Project Review and Expert Testimony: Our staff has been retained on numerous occasions to review previously conducted instream flow studies and project designs, provide an independent evaluation, and participate in state and federal proceedings as an expert witness involving disputes over study conduct, the potential for project impacts, and required mitigation.

Fish Passage and Migration Barrier Evaluations: We have performed a number of anadromous fish barrier evaluations to assess potential passage enhancement alternatives, and have provided technical assistance with the design of fish ladders, both conventional (pool-and-weir, Alaskan, steep pass) and naturalized (embedded boulders with resting pools).

SEFA Flow Pathway
SEFA flow pathway.