Barotrauma caused by rapid decompression during hydroturbine (turbine) passage may occur as fish move through the low pressure region below the turbine runner. This scenario is of particular concern in North American rivers with populations of ESA-listed salmon. The US Army Corps of Engineers (USACE) and the Pacific Northwest National Laboratory released Sensor Fish into lower Snake and Columbia River turbines to determine the magnitude and rate of pressure change fish might experience.
Irrigation modernisation is booming globally because of the increasing demand on water and food. However, irrigation infrastructures can injure fish or entrain them into irrigation water. Screening is an effective method to mitigate fish entrainment.
Many riverine fish species disperse downstream as eggs, juveniles, or adults, which can expose them to injury and death at hydraulic structures. Low-head weirs are one example of a structure that can kill fish, and this impact has been shown to be substantially higher for undershot weirs when compared to overshot weirs. In this study, autonomous sensor devices were released at an overshot and undershot weir under similar discharges to assess what stressors maybe contributing to differences in the survival rates of fish.
Spillway passage is one of the commonly accepted dam passage alternatives for downstream-migrating salmonids and other species. Fish passing in spill near the water surface may have improved chances of survival over fish that pass deeper in the water column near spillway structures. In this study, an autonomous sensor device (Sensor Fish) was deployed in 2005 to evaluate fish passage conditions through the Removable Spillway Weir (RSW) at Ice Harbor Dam on the Snake River in south-central Washington State.
Fish passing through dams or other hydraulic structures may be injured or killed despite advances in turbine design, project operations, and other fish bypass systems. The Sensor Fish (SF) device is an autonomous sensor package that characterizes the physical conditions and stressors to which fish are exposed during passage through hydro facilities. It was designed to move passively as a neutrally buoyant object through severe hydraulic environments, while collecting high-resolution sensor data.
Fish passage conditions over spillways are important for the operations of hydroelectric dams because spillways are usually considered as a common alternative passage route to divert fish from the turbines. The objectives of this study were to determine the relative potential of fish injury during spillway passage both before and after the installation of baffle blocks at Boundary Dam, and to provide validation data for a model being used to predict total dissolved gas levels.