Evaluation and Development of Fish Passage Structures and Technologies
Dams can be found in just about every major river, and for good reason. Society has received many benefits like flood control, hydropower, water supply storage, and places to recreate. However, many fish and other life in our rivers can’t swim around these barriers. Often, the best spot for a fish to live and reproduce is out of reach because they can’t pass by a dam. This has not gone unnoticed. Many structures called fishways have been built that are meant to give fish a path to swim around these barriers. But all too often, fish are unable to find, enter, and successfully swim through these pathways.
Our study plan is focused on solving as much of this puzzle as possible. Research projects will focus on both technical and nature-like fishways, either in their entirety or simply components of the fishway. Improving attraction, entry, and passage through the body of each fishway type for a wide variety of species, particularly those species of interest to the USGS and our cooperators, will be the primary objective of this research.
Test procedures will include a combination of 1) physical scale models, 2) full-scale prototype experimental fishways, and 3) numerical models.
Physical scale models will be built within the Hydraulics Laboratory at the Conte Anadromous Fish Research Laboratory (CAFRLL to evaluate and quantify hydraulic conditions within a fishway. Many of these experiments will be conducted in a rectangular open channel flume (0.914 m wide, 1.219 m deep, and 4.953 m long, with a plywood floor and acrylic sides), hereafter referred to as the “scale model flume”. Flow into the scale model flume is measured using one of three calibrated venturi meters. Models can be scaled down to represent almost any fish passage structure; i.e., prototype fishway, entrance, downstream bypass, bar rack, louver, screening, etc. Results from scale modeling are sometimes sufficient in themselves to answer fish passage research questions, but often model results are applied to further investigations with full-scale prototypes and live, actively migrating fishes in the CAFRL Flume Facility.
Full-scale experimental fish passage structures will be constructed within the Flume Facility at CAFRL to evaluate the attraction efficiency, entry rates, and overall passage success of the fishway. The facility consists of three 38 m long open channel main flumes; two flumes are 3 m wide, and one is 6 m wide. Some experiments may involve only hydraulic measurements and/or mechanical function of structures that cannot be performed at the physical model scale. For biological evaluation studies, actively migrating wild diadromous or riverine fishes will be used. Movements of test fish are monitored in the full-scale prototype primarily using PIT (passive integrated transponder) telemetry and video, although in some cases radio and acoustic telemetry may also be required. Standard statistical techniques (ANOVA, regression, multivariate methods, etc.) will form the basis of most data analyses. Movements and passage performance of test fish are often best quantified as rates, and time-to-event analysis will be a standard tool for many of these studies.
Numerical models (e.g. computational fluid dynamics) will also be utilized within this Study Plan to better understand hydraulics within fish passage structures. The primary numerical modeling software to be used is OpenFOAM. OpenFOAM is a finite-volume code that iteratively solves the conservation of mass and momentum equations over a set of discrete control volumes within a specified model domain.
Dams can be found in just about every major river, and for good reason. Society has received many benefits like flood control, hydropower, water supply storage, and places to recreate. However, many fish and other life in our rivers can’t swim around these barriers. Often, the best spot for a fish to live and reproduce is out of reach because they can’t pass by a dam. This has not gone unnoticed. Many structures called fishways have been built that are meant to give fish a path to swim around these barriers. But all too often, fish are unable to find, enter, and successfully swim through these pathways.
Our study plan is focused on solving as much of this puzzle as possible. Research projects will focus on both technical and nature-like fishways, either in their entirety or simply components of the fishway. Improving attraction, entry, and passage through the body of each fishway type for a wide variety of species, particularly those species of interest to the USGS and our cooperators, will be the primary objective of this research.
Test procedures will include a combination of 1) physical scale models, 2) full-scale prototype experimental fishways, and 3) numerical models.
Physical scale models will be built within the Hydraulics Laboratory at the Conte Anadromous Fish Research Laboratory (CAFRLL to evaluate and quantify hydraulic conditions within a fishway. Many of these experiments will be conducted in a rectangular open channel flume (0.914 m wide, 1.219 m deep, and 4.953 m long, with a plywood floor and acrylic sides), hereafter referred to as the “scale model flume”. Flow into the scale model flume is measured using one of three calibrated venturi meters. Models can be scaled down to represent almost any fish passage structure; i.e., prototype fishway, entrance, downstream bypass, bar rack, louver, screening, etc. Results from scale modeling are sometimes sufficient in themselves to answer fish passage research questions, but often model results are applied to further investigations with full-scale prototypes and live, actively migrating fishes in the CAFRL Flume Facility.
Full-scale experimental fish passage structures will be constructed within the Flume Facility at CAFRL to evaluate the attraction efficiency, entry rates, and overall passage success of the fishway. The facility consists of three 38 m long open channel main flumes; two flumes are 3 m wide, and one is 6 m wide. Some experiments may involve only hydraulic measurements and/or mechanical function of structures that cannot be performed at the physical model scale. For biological evaluation studies, actively migrating wild diadromous or riverine fishes will be used. Movements of test fish are monitored in the full-scale prototype primarily using PIT (passive integrated transponder) telemetry and video, although in some cases radio and acoustic telemetry may also be required. Standard statistical techniques (ANOVA, regression, multivariate methods, etc.) will form the basis of most data analyses. Movements and passage performance of test fish are often best quantified as rates, and time-to-event analysis will be a standard tool for many of these studies.
Numerical models (e.g. computational fluid dynamics) will also be utilized within this Study Plan to better understand hydraulics within fish passage structures. The primary numerical modeling software to be used is OpenFOAM. OpenFOAM is a finite-volume code that iteratively solves the conservation of mass and momentum equations over a set of discrete control volumes within a specified model domain.