Cyprinid passage performance in an experimental multislot fishway across distinct seasons

2019 ◽  
Vol 70 (6) ◽  
pp. 881 ◽  
Author(s):  
Filipe Romão ◽  
Ana L. Quaresma ◽  
José M. Santos ◽  
Paulo Branco ◽  
António N. Pinheiro
Keyword(s):  
Fish Community ◽  
Woody Debris ◽  
Cost Effective ◽  
Ecological Traits ◽  
Vertical Slot ◽  
Longitudinal Connectivity ◽  
Vertical Slot Fishway ◽  
Iberian Chub ◽  
Effective Design ◽  
Entry Efficiency

New engineering solutions are required to minimise the effects of an increasing number of anthropogenic barriers on watercourses. Longitudinal connectivity must be provided through fishways to allow free passage for the whole fish community. Recently, a multislot fishway (MSF) was developed, with two consecutive vertical slots that divide the overall head drop by two, thus reducing the flow velocity, the magnitude of turbulence and operational discharge compared with a standard vertical slot fishway (VSF) with similar pool and slot dimensions. The present study assessed the effectiveness of a MSF design for two cyprinid species with different ecological traits, under laboratory conditions, namely the Iberian barbel (Luciobarbus bocagei), a large-bodied potamodromous benthic fish, and the southern Iberian chub (Squalius pyrenaicus), a small-bodied water column fish. Experiments were conducted in a full-scale experimental fishway, in spring and autumn. Results showed differences in passage performance between seasons and species. During spring, chub had a higher entry efficiency and shorter transit time to fully negotiate the fishway, whereas no seasonal differences were found for the barbel. Overall, the MSF could be considered a cost-effective design for cyprinids with different ecological traits because it offers lower operational costs than a standard VSF. However, concerns about the entrance and attraction conditions should be addressed. In addition, because of the lower operational discharge, the propensity for obstruction with woody debris and sediments should not be disregarded.

scholarly journals Multislot Fishway Improves Entrance Performance and Fish Transit Time over Vertical Slots

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 275
Author(s):  
Filipe Romão ◽  
Ana L. Quaresma ◽  
José M. Santos ◽  
Susana D. Amaral ◽  
Paulo Branco ◽  
...  
Keyword(s):  
Transit Time ◽  
Reynolds Shear Stress ◽  
Cost Effective ◽  
Fish Passage ◽  
Entrance Time ◽  
Trade Offs ◽  
Vertical Slot ◽  
Longitudinal Connectivity ◽  
Water Uses ◽  
Entry Efficiency

Pool-type fishways have been increasingly tested to improve fish passage performance and minimize migration delays. Designing cost-effective fishways is essential for a trade-off between water uses and successful longitudinal connectivity restoration. The multislot fishway (MSF) concept, which operates with 30–50% lower discharge than a vertical slot fishway (VSF), was recently developed. This study assessed and compared the entrance performance (entrance time; entry efficiency) and transit times of two cyprinids for VSFs and MSFs. Four configurations, with the same structural characteristics (slope; water depth; head drop; pool width and depth), operating with different discharges (Q), were tested (VSF 1: Q = 112 L·s−1; VSF 2: Q = 80 L·s−1; MSF 1: Q = 58 L·s−1; MSF 2: Q = 37 L·s−1). Hydrodynamics characterization was performed using a numerical model. Results showed that entry efficiency was higher in MSFs than in VSFs, while entrance time and transit time were overall lower. Numerical modelling revealed that velocities were around 30% lower in MSFs, and turbulence could reach a difference of around 70% in Reynolds shear stress and 50% in turbulent kinetic energy. Overall, MSFs can be considered as a cost-effective fishway solution that can balance the trade-offs between divergent interests in water uses.

Analysis of fishways in the Middle and Lower Jinsha River Basin (China)

2021 ◽  
Author(s):  
Siqi Tong ◽  
Silke Wieprecht ◽  
Martin Schletterer
Keyword(s):  
River Basin ◽  
Jinsha River ◽  
Vertical Slot ◽  
Upper Yangtze River ◽  
Artificial Breeding ◽  
Longitudinal Connectivity ◽  
Target Fish ◽  
Regional Sustainable Development ◽  
Vertical Slot Fishway ◽  
Hydropower Stations

<p>This study was carried out in the middle and lower reaches of the Jinsha River in southwest China, which represents the upper Yangtze River. Hydraulic structures (14 cascade hydropower stations) are planned and/or constructed in this system, which is considered as largest hydropower base. We aim to summarize appropriate measures to restore the riverine continuum in the middle and lower reaches of the Jinsha River, where high-head cascade hydropower dams are located or planned.</p><p>We distributed a questionnaire to Chinese researchers in the related fields (scientists, hydropower operators and NGOs in China, n = 60). According to the responses, fishways, fish lift, fish lock, trap-and-truck system as well as fish hatcheries (artificial breeding) are recognized to ensure passing respectively preserving fish in the Jinsha River basin.</p><p>A longitudinal connectivity assessment of the study area revealed a severely disturbed continuity status. Based on the biological analyses of the demands of the target fish species and review of fish pass technologies, a vertical-slot fishway is proposed.</p><p>Considering the dam heights and the geographical conditions, it is recommended to combine the vertical-slot fishway with these alternatives to achieve a higher efficiency in passing fish as well as to recover the river continuity towards regional sustainable development.</p>

Can a low-gradient vertical-slot fishway provide passage for a lowland river fish community?

2008 ◽  
Vol 59 (4) ◽  
pp. 332 ◽  
Author(s):  
Ivor G. Stuart ◽  
Brenton P. Zampatti ◽  
Lee J. Baumgartner
Keyword(s):  
Fish Community ◽  
Performance Criteria ◽  
Native Fish ◽  
Regulated Rivers ◽  
Pit Tag ◽  
Vertical Slot ◽  
Murray Darling Basin ◽  
Vertical Slot Fishway ◽  
Reading System ◽  
River Fish

Fishways are commonly used to restore native fish movements in regulated rivers. In the Murray-Darling Basin, Australia, 14 fishways are to be built by 2011 to improve passage along 2225 km of the river. The first of these fishways, constructed in 2003, is a vertical-slot design with low water velocities (0.98–1.4 m s–1) and turbulence (average 42 W m–3). This design was selected to provide passage for individuals between 20 and 1000 mm long. To determine passage success, trapping and a remote automated passive integrated transponder (PIT) tag reading system was used from October 2003 to February 2006. In 57 24-h samples at the exit (upstream end) and entrance (downstream end), 13 species and 30 409 fish were collected at a maximum rate of 4415 fish per day. Fish between 31 and 1030 mm successfully ascended the fishway. However, significantly smaller (<31 mm) fish and small-bodied (<50 mm) carp gudgeons (Hypseleotris spp.), a species previously considered non-migratory, were sampled downstream from the entrance of the fishway. The remote PIT tag reading system revealed that 81% of native golden perch (Macquaria ambigua) and 87% of non-native common carp (Cyprinus carpio) successfully ascended the fishway. These data will help maximise the efficiency of future fishways against a series of pre-determined performance criteria.

scholarly journals Numerical Investigation of Hydraulics in a Vertical Slot Fishway with Upgraded Configurations

Water ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 2711
Author(s):  
Mohammad Ahmadi ◽  
Amir Ghaderi ◽  
Hossein MohammadNezhad ◽  
Alban Kuriqi ◽  
Silvia Di Francesco
Keyword(s):  
Kinetic Energy ◽  
Turbulent Kinetic Energy ◽  
Large Diameter ◽  
Maximum Velocity ◽  
Cost Effective ◽  
Hydraulic Structures ◽  
The Sustainable Development ◽  
Vertical Slot ◽  
Vertical Slot Fishway ◽  
Design Cost

The implementation of vertical slot fishway (VSF) has been demonstrated to be an effective mitigation measure to alleviate extensive river fragmentation by artificial hydraulic structures such as weirs and dams. However, non-suitable flow velocity and turbulent kinetic energy significantly affect fish swimming behavior and, as a result, hinder such facilities’ performance. Therefore, this study’s main objective is to propose a new configuration of VSF that can allow the passage of different fish species under frequent variations of flow discharge. To achieve that objective several novel configurations of VSF were numerically investigated using the FLOW-3D® model. Namely, five variants of angles between baffles, four different pool widths, and another upgraded version of VSF by introducing cylindrical elements positioned after the opening behind the baffles were tested. Results show that smaller angles between baffles increase the Vmax and decrease the maximum turbulent kinetic energy (TKEmax); the opposite result was obtained when increasing angles between baffles. Namely, the Vmax was increased up to 17.9% for α = 0° and decreased up to 20.37% for α = 37°; in contrast, TKEmax decreased up to −20% for α = 0° and increased up to 26.5% for α = 37°. Narrowing the pool width increased the Vmax linearly; nevertheless, it did not significantly affect the TKEmax as the maximum difference was only +3.5%. Using cylinders with a large diameter decreased the Vmax and increased TKEmax; in contrast, using cylinders with smaller diameters further reduced the Vmax velocity inside the pool while increasing the TKEmax. However, in the case of cylinders, the dimension of the recirculation depended on the configuration and arrangement of the cylinder within the pool. Overall, the maximum velocity was reached at near 77% of the water depth in all cases. Finally, solution-oriented findings resulted from this study would help water engineers to design cost-effective VSF fishways to support the sustainable development of hydraulic structures while preserving aquatic biodiversity.

Price structures for electricity supply and potential consequences for building services systems

2021 ◽  
pp. 014362442199081
Author(s):  
Roger Hitchin
Keyword(s):  
Cost Effective ◽  
Building Design ◽  
Electricity Supply ◽  
Cooling Systems ◽  
Price Structure ◽  
Heating And Cooling ◽  
Future System ◽  
The Cost ◽  
Supply Systems ◽  
Effective Design

Policies to reduce carbon emissions are leading to substantial changes in the demand for electricity and to the structure of electricity supply systems, which will alter the cost structure of electricity supply. This can be expected to result in corresponding changes to the price structure faced by customers. This note is an initial exploration of how possible new price structures may impact on HVAC system and building design and use. Changes in the price structure of electricity supply (separately from changes in price levels) can significantly affect the cost-effective design and operation of building services systems; especially of heating and cooling systems. The nature and implications of these changes can have important implications for future system design and operation.

Polymorphic Control for Cost-Effective Design of Optical Networks

2000 ◽  
Vol 11 (1) ◽  
pp. 17-26 ◽  
Author(s):  
Qiao Chunming ◽  
Mei Yousong ◽  
Yoo Myungsik ◽  
Zhang Xijun
Keyword(s):  
Optical Networks ◽  
Cost Effective ◽  
Effective Design
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