Parameters to assess a pool and weir fish pass and how to measure them: Field experiences

• Jorge Valbuena Castro ^[1]
  1. [1] Universidad de Valladolid

     Universidad de Valladolid

     Valladolid, España

     
• Localización: XI young researchers meeting on conservation and sustainable use of forest systems / coord. por Elena Hidalgo Rodríguez, Francisco Javier Dorado Reyes, Ainhoa Iñiguez Soto, Diego A. Damián Carrión, Samuel Gato Martín, Guillermo Jové Alcalde, Raúl Arcadio Fernández González, 2017, ISBN 978-84-617-9574-1, pág. 43
• Idioma: inglés
• Texto completo no disponible (Saber más ...)
• Resumen

  • During thousands of years, all around the world, humans have built a wide range of obstacles on the rivers with different purposes. These obstacles had a very negative impact for the fish fauna. The most frequent option to minimize or even eliminate this negative impact are the fish passes also known as fishways. Especially the ones called pool and weir fish passes. Pool and weir passes let fish swim upstream and downstream over the obstacle whenever they need, enabling their free movements along the river without any assistance. Fish passes had been built on a large scale already. Now scientific and technical community is evaluating their functionality to ensure they offer their maximum benefits. A whole assessment process starts with a hydraulic study that identifies the most important problems of the device and how to solve them. The evaluation should also include a biological study that provide us with information about the real effectiveness of the structure. However, because of the complexity of the biological studies, in most of situations biological procedures are not carried out and fish passes only are evaluated byhydraulic criteria. In addition, these studies are developed following various methods and attending to different parameters and variables creating confusion. This work aim to establish how to assess all the pool and weir fish passes in the field with the minimum resources. To do this, we explain which are and how to measure the most important design (connection between pools and their dimensions, …) topographical (difference between cross-walls, …) and hydraulic parameters (difference in water level between pools, water depth, ...). All these are necessary to analyze the suitability of these structures for fish from a hydraulic point of view.