Understanding the factors that injure or kill turbine-passed fish is important to the operation and design of the turbines. Motion-tracking analysis was performed on high-speed, high-resolution digital videos of juvenile salmonids exposed to a laboratory-generated shear environment to isolate injury mechanisms. Hatchery-reared fall chinook salmon (Oncorhynchus tshawytscha, 93–128 mm in length) were introduced into a submerged, 6.35-cm-diameter water jet at velocities ranging from 12.2 to 19.8 m·s–1, with a reference control group released at 3 m·s–1. Injuries typical of turbine-passed fish were observed and recorded. Three-dimensional trajectories were generated for four locations on each fish released. Time series of velocity, acceleration, force, jerk, and bending angle were computed from the three-dimensional trajectories. The onset of minor, major, and fatal injuries occurred at nozzle velocities of 12.2, 13.7, and 16.8 m·s–1, respectively. Opercle injuries occurred at 12.2 m·s–1 nozzle velocity, while eye injuries, bruising, and loss of equilibrium were common at velocities of 16.8 m·s–1 and above. Of the computed dynamic parameters, acceleration showed the strongest predictive power for eye and opercle injuries and overall injury level, and it may provide the best potential link between laboratory studies of fish injury, field studies designed to collect similar data in situ, and numerical modeling.

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As part of the research supported by U.S. Department of Energy (DOE) Advanced Hydropower Turbine System (AHTS) Program, the Pacific Northwest National Laboratory (PNNL) conducted a study where age-0 and age-1 chinook salmon, as well as several other types of fish, were released into a submerged water jet to quantify injuries caused by shear stresses and turbulence (Neitzel et al. 2000). The fish releases were videotaped. These videotape records were digitized and analyzed using new methods to identify the injury mechanisms and the stresses involved. Visible external injuries sustained by fish in this study generally occurred during the initial contact with the jet and not during the tumbling that occurred after the fish fully entered the turbulent flow. The inertial stresses of tumbling, however, may cause temporary or even permanent vestibular and neurological injuries. Such injuries can result in disorientation and loss of equilibrium, which are life threatening in the "natural" environment. Operculum injuries predominated at moderate water jet speeds (12 and 15 m•s-1). At the highest speed, eye, operculum, isthmus, and gill injuries were equally common, and disorientation was most common. Bruising and descaling were relatively rare, especially for age-0 fish. Age-0 fish were less susceptible than the larger age-1 fish to all visible injury types, especially at lower speeds. This is presumably because age-0 fish have less mass and inertia, and therefore sustain smaller forces on exposed organs during acceleration. Alternatively, age-0 fish were substantially more susceptible to behavioral impairments such as disorientation. This may also relate to the smaller mass of the age-0 fish. The less massive age-0 fish sustain larger accelerations and jerks, which may be important sources of the internal injuries to the vestibular and neurological systems. All the dynamic parameters computed from the bulk motion of the fish (velocity, jerk, and force) were positively correlated with injury level, based on the results of this study. Multinomial response model results further suggested that force is most predictive of injury.

The volume of water available for groundwater recharge through the infiltration of surface runoff in Cold and Dry Creeks was estimated for a 100-year storm and the Probable Maximum Precipitation (PMP) of Skaggs and Walters (1981). A 100-year, 7-day design storm was developed from 40 years of precipitation data measured at the Hanford Meteorological Station (HMS). Runoff measured in Upper Cold Creek was used with HMS precipitation data to calculate curve numbers for the Soil Conservation Service rainfall-runoff model. The estimated water available for recharge from surface runoff produced by the 100-year storm is 3-6 times the annual recharge rate from direct infiltration of precipitation over the Hanford Site. Potential recharge from the PMP is 7-11 times the annual volume of direct recharge.iii SummaryThe rate of groundwater movement in the uppermost unconfined aquifer beneath the Hanford Site to the Columbia River is dictated by an east to west head gradient in the aquifer. This gradient is in turn influenced by the amount and spatial distribution of recharge. The purpose of this study was to estimate the volume of water available for groundwater recharge from infiltration of surface runoff in Cold and Dry Creeks resulting from a 100-year, 7-day storm.The approach used to estimate potential recharge was to construct numerical models to simulate rainfall-runoff and channel recharge processes and use these models with a 100-year design storm as input. Specific tasks addressed in FY1999 included: 1) constructing a digital elevation model of the study area, 2) gaining an understanding of runoff generation to guide development of the design storm and numerical models, 3) developing an appropriate design storm using 40 years of precipitation data from the Hanford Meteorological Station, and 4) constructing a numerical rainfall-runoff model of Cold and Dry Creeks.The estimated water available for recharge from surface runoff produced by the 100-year storm is 3-6 times the annual recharge rate from direct infiltration of precipitation over the Hanford Site. Potential recharge from the PMP is 7-11 times the annual volume of direct recharge.v

At The Dalles Dam on the Columbia River, fish are believed to sustain injury from exposure to turbulence and from collisions with baffle blocks and end sills in the stilling basin at high spillway discharges. Because taking velocity measurements would be exceedingly difficult in this environment, a system of pressure transducers was installed to record high-frequency pressure data for a range of spillway discharges. The sensors were mounted below two of the spillbays on the tops, faces, and sides of baffle blocks; in the gaps between baffle blocks; and on the top and face of the end sill. Statistical analyses on results from three sensors below one of the two spillways showed that mean pressure increased during head-on flow, decreased in flow separation zones, and was proportional to water depth. Power spectra indicate increased low-frequency spectral power with increased discharge, typical spectral decay rates, and the existence of spectral peaks of possible hydraulic origin. The high-frequency pressure data collected at full scale in extremely turbulent environments will contribute to efforts to improve fish passage and to develop and validate three-dimensional computational fluid dynamics models. RÉSUMÉAu barrage de Dalles sur le fleuve Columbia, les poissons sont censés supporter des dommages dus à leur exposition à la turbulence et aux collisions avec les blocs latéraux et les seuils à l'extrémité du bassin de tranquillisation lors des décharges importantes. En raison de la difficulté excessive des mesures de vitesse dans cet environnement, un système de capteurs de pression a été installé afin d'enregistrer les données de pression à haute fréquence pour toute une gamme de décharges de déversoir. Les sondes ont été montées en-dessous de deux des déversoirs, sur le dessus, la face, et les côtés des blocs latéraux; dans les espaces entre les blocs latéraux; et sur le dessus et la face du seuil d'extrémité. Les analyses statistiques des résultats provenant de trois sondes situées en-dessous d'un des deux déversoirs ont montré que la pression moyenne augmentait pendant l'écoulement frontal, diminuait dans des zones de séparation d'écoulement, et était proportionnelle à la profondeur d'eau. Les spectres de puissance indiquent un accroissement de la puissance spectrale de basse fréquence avec l'augmentation du débit, des taux spectraux typiques de décroissance, et l'existence de pics spectraux probablement d'origine hydraulique. Les données de pression à haute fréquence rassemblées à grande échelle dans ces environnements extrêmement turbulents contribueront aux efforts réalisés pour améliorer le passage des poissons et pour développer et valider les modèles numériques tridimensionnels de dynamique des fluides.