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Integrating Ecohydraulics in River Restoration: Advances in Science and Applications

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A special issue of Sustainability (ISSN 2071-1050). This special issue belongs to the section "Environmental Sustainability and Applications".

Deadline for manuscript submissions: closed (31 May 2019) | Viewed by 53819

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Special Issue Editors

Dr. José Maria Santos

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Guest Editor

Forest Research Centre, School of Agriculture, University of Lisbon, Lisbon, Portugal
Interests: freshwater fish; fish passage; ecohydraulics; fish migration; connectivity; river restoration
Special Issues, Collections and Topics in MDPI journals

Dr. Isabel Boavida

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Guest Editor

Civil Engineering Research and Innovation for Sustainability, Instituto Superior Técnico, University of Lisbon, Lisbon, Portugal
Interests: ecohydraulics; freshwater habitat modelling; freshwater fish; sustainability
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Rivers have been intensively degraded due to increasing anthropogenic impacts from a growing population in a continuously-developing world. Conflict demands on freshwater resources, exacerbated by climate change, present a difficult dilemma for scientists and managers: Until when and how much can a river (and its natural flow regime) be altered while still maintaining processes and functions, and guaranteeing sustainable aquatic populations? Accordingly, most rivers in the world have been suffering pressures resulting from increasing dam and weir construction, habitat degradation, flow regulation, water pollution/abstraction and spread of invasive species. In addition, it is expected that global warming will further stimulate conflicts in water use leading to disturbances in river ecosystems. Science-based knowledge regarding solutions (e.g., environmental flows, dam removal, improvement of fish passes, adoption of fish-friendly hydropower solutions, riparian vegetation management, etc.) to counteract the effects of river degradation, and melding principles of aquatic ecology and engineering hydraulics, is thus urgently needed to guide present and future river restoration actions. This Special Issue of Sustainability aims to compile new information on fundamental scientific research and applications regarding the integration of ecohydraulics in river restoration (see keyword research topics below), ranging from field studies to laboratory experiments that have application to real-world challenges. Papers selected for this Special Issue will be subject to a rigorous peer-review procedure with the aim of rapid and wide dissemination of results.

Dr. José Maria Santos
Dr. Isabel Boavida
Guest Editors

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Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

Dam/weir retrofitting and removal
Environmental flows
Riparian and aquatic vegetation dynamics
Fish passage and migration
Sustainable hydropower
Prioritization of river connectivity for sustainable fisheries
Spawning grounds
Habitat modeling
Invasive species management

Published Papers (13 papers)

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Research

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16 pages, 2221 KiB

Open AccessArticle

Passability of Potamodromous Species through a Fish Lift at a Large Hydropower Plant (Touvedo, Portugal)

by Daniel Mameri, Rui Rivaes, João M. Oliveira, João Pádua, Maria T. Ferreira and José M. Santos

Sustainability 2020, 12(1), 172; https://doi.org/10.3390/su12010172 - 24 Dec 2019

Cited by 9 | Viewed by 3272

Abstract

River fragmentation by large hydropower plants (LHP) has been recognized as a major threat for potamodromous fish. Fishways have thus been built to partially restore connectivity, with fish lifts representing the most cost-effective type at high head obstacles. This study assessed the effectiveness with which a fish lift in a LHP on the River Lima (Touvedo, Portugal), allows potamodromous fish—Iberian barbel (Luciobarbus bocagei), Northern straight-mouth nase (Pseudochondrostoma duriense) and brown trout (Salmo trutta fario)- to migrate upstream. Most fish (79.5%) used the lift between summer and early-fall. Water temperature was the most significant predictor of both cyprinids’ movements, whereas mean daily flow was more important for trout. Movements differed according to peak-flow magnitude: nase (67.8%) made broader use of the lift in the absence of turbined flow, whereas a relevant proportion of barbel (44.8%) and trout (44.2%) passed when the powerhouse was operating at half (50 m³s⁻¹) and full-load (100 m³s⁻¹), respectively. Size-selectivity found for barbel and trout could reflect electrofishing bias towards smaller sizes. The comparison of daily abundance patterns in the river with fish lift records allowed the assessment of the lift’s efficacy, although biological requirements of target species must be considered. Results are discussed in the context of management strategies, with recommendations for future studies. Full article

(This article belongs to the Special Issue Integrating Ecohydraulics in River Restoration: Advances in Science and Applications)

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16 pages, 1863 KiB

Open AccessCommunication

Habitat Enhancement Solutions for Iberian Cyprinids Affected by Hydropeaking: Insights from Flume Research

by Maria João Costa, António N. Pinheiro and Isabel Boavida

Sustainability 2019, 11(24), 6998; https://doi.org/10.3390/su11246998 - 07 Dec 2019

Cited by 11 | Viewed by 3221

Abstract

Due to peak electricity demand, hydropeaking introduces rapid and artificial flow fluctuations in the receiving river, which alters the river hydromorphology, while affecting the downstream ecological integrity. The impacts of hydropeaking have been addressed in flumes and in rivers. However, few studies propose mitigation solutions based on fish responses. The objective of this communication was to assemble the methods and outputs of flume research focused on Iberian cyprinids and to present recommendations to be used by freshwater scientists and hydropower producers. Emphasis was given to the critical role of integrating ecology and hydraulics to find the causal pathway between a flow change and a measurable fish response. The use of diverse behaviour quantification methods, flow sensing technologies, and statistical tools were decisive to strengthen the validity of the findings and to identify fish-fluid relationships, according to flow events. This communication encourages further research to identify flow thresholds for key life-cycle stages and complementary river studies to design and assess mitigation solutions for hydropeaking. Although the research focused on an Iberian cyprinid, the methods suggested have the potential to be extended to other fish species affected by hydropeaking. Full article

(This article belongs to the Special Issue Integrating Ecohydraulics in River Restoration: Advances in Science and Applications)

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24 pages, 4430 KiB

Open AccessArticle

Hydropower Development and Fishways: A Need for Connectivity in Rivers of the Upper Paraná Basin

by Sergio Makrakis, Ana P. S. Bertão, Jhony F. M. Silva, Maristela C. Makrakis, Fco. Javier Sanz-Ronda and Leandro F. Celestino

Sustainability 2019, 11(13), 3749; https://doi.org/10.3390/su11133749 - 09 Jul 2019

Cited by 24 | Viewed by 5434

Abstract

South American rivers have become intensely affected by the construction of hydroelectric dams that block the river’s connectivity for migratory fish species. In order to mitigate the problems caused by dams and to reestablish connections between habitats, fishways are implemented. Fishways are structures that aid fish in overcoming obstacles and help preserve migratory, reproductive, and feeding routes. This study performed an inventory of all hydropower plants—present and future—in the Upper Paraná River, with the objective of identifying fishways unknown to scientific literature, as well as the task of mapping them. By doing so, the current situation of structural connectivity via fishways in the Upper Paraná River Basin was described. Overall, 389 dams along 209 rivers were identified; of these, only 9% (35 dams) have fishways. In addition, an alarming explosion of future medium-sized hydropower plants was observed, with an expectation of an almost 500% increase in relation to those existing. This data reveals a trend of reduction of free-flowing river stretches, which are crucial habitats for Neotropical potamodromous species, and point to a deficiency in the structural connectivity of existing hydropower dams. Furthermore, if the implementations of these expected constructions are associated with limited connectivity as a result of the absence of fishways, the management of fisheries and their resources in the Upper Paraná River may become unsustainable. Full article

(This article belongs to the Special Issue Integrating Ecohydraulics in River Restoration: Advances in Science and Applications)

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24 pages, 4837 KiB

Open AccessArticle

Flow–Vegetation Interaction in a Living Shoreline Restoration and Potential Effect to Mangrove Recruitment

by Kelly M. Kibler, Vasileios Kitsikoudis, Melinda Donnelly, David W. Spiering and Linda Walters

Sustainability 2019, 11(11), 3215; https://doi.org/10.3390/su11113215 - 10 Jun 2019

Cited by 19 | Viewed by 5182

Abstract

Hydrodynamic differences among shorelines with no vegetation, reference vegetation (mature mangrove), and vegetation planted on restored shoreline (marsh grass and young mangrove) were compared based on field observations 6.5 years after living shoreline restoration. Mean current velocities and waves were more strongly attenuated in vegetation (from channel to shoreline: 80–98% velocity decrease and 35–36% wave height reduction) than in bare shoreline (36–72% velocity decrease, 7% wave height reduction, ANOVA: p < 0.001). Normalized turbulent kinetic energy dissipation rates were significantly higher in reference vegetation (0.16 ± 0.03 m⁻¹) than in restored (0.08 ± 0.02 m⁻¹) or bare shoreline (0.02 ± 0.01 m⁻¹, p < 0.001). Significant differences in the current attenuation and turbulence dissipation rates for the reference and planted vegetation are attributed to the observed differences in vegetation array and morphology. Although the hydrodynamic analyses did not suggest limitations to recruitment, mangrove seedlings were not observed in restored vegetation, while four recruited seedlings/m were counted in the reference vegetation. The lack of recruitment in the restored shoreline may suggest a lag in morphological habitat suitability (slope, sediment texture, organic matter content) after restoration. Although hydrodynamics suggest that the restored site should be functionally similar to a reference condition, thresholds in habitat suitability may emerge over longer timescales. Full article

(This article belongs to the Special Issue Integrating Ecohydraulics in River Restoration: Advances in Science and Applications)

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17 pages, 2116 KiB

Open AccessArticle

Analysing Habitat Connectivity and Home Ranges of Bigmouth Buffalo and Channel Catfish Using a Large-Scale Acoustic Receiver Network

by Eva C. Enders, Colin Charles, Douglas A. Watkinson, Colin Kovachik, Douglas R. Leroux, Henry Hansen and Mark A. Pegg

Sustainability 2019, 11(11), 3051; https://doi.org/10.3390/su11113051 - 30 May 2019

Cited by 12 | Viewed by 4113

Abstract

The determination if fish movement of potadromous species is impeded in a river system is often difficult, particularly when timing and extent of movements are unknown. Furthermore, evaluating river connectivity poses additional challenges. Here, we used large-scale, long-term fish movement to study and identify anthropogenic barriers to movements in the Lake Winnipeg basin including the Red, Winnipeg, and Assiniboine rivers. In the frame of the project, 80 Bigmouth Buffalo (Ictiobus cyprinellus) and 161 Channel Catfish (Ictalurus punctatus) were tagged with acoustic transmitters. Individual fish were detected with an acoustic telemetry network. Movements were subsequently analyzed using a continuous-time Markov model (CTMM). The study demonstrated large home ranges in the Lake Winnipeg basin and evidence of frequent transborder movements between Canada and the United States. The study also highlighted successful downstream fish passage at some barriers, whereas some barriers limited or completely blocked upstream movement. This biological knowledge on fish movements in the Lake Winnipeg basin highlights the need for fish passage solutions at different obstructions. Full article

(This article belongs to the Special Issue Integrating Ecohydraulics in River Restoration: Advances in Science and Applications)

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25 pages, 2003 KiB

Open AccessArticle

Dam Removal Effects on Benthic Macroinvertebrate Dynamics: A New England Stream Case Study (Connecticut, USA)

by Helen M. Poulos, Kate E. Miller, Ross Heinemann, Michelle L. Kraczkowski, Adam W. Whelchel and Barry Chernoff

Sustainability 2019, 11(10), 2875; https://doi.org/10.3390/su11102875 - 21 May 2019

Cited by 7 | Viewed by 3355

Abstract

Dam removal is an increasingly common stream restoration tool. Yet, removing dams from small streams also represents a major disturbance to rivers that can have varied impacts on environmental conditions and aquatic biota. We examined the effects of dam removal on the structure, function, and composition of benthic macroinvertebrate (BMI) communities in a temperate New England stream. We examined the effects of dam removal over the dam removal time-series using linear mixed effects models, autoregressive models, non-metric multidimensional scaling, and indicator and similarity analyses. The results indicated that the dam removal stimulated major shifts in BMI community structure and composition above and below the dam, and that the BMI communities are becoming more similar over time. The mixed model analysis revealed that BMI functional groups and diversity were significantly influenced by sample site and several BMI groups also experienced significant interactions between site and dam stage (P < 0.05), while the multivariate analyses revealed that community structure continues to differ among sites, even three years after dam removal. Our findings indicate that stream restoration through dam removal can have site-specific influences on BMI communities, that interactions among BMI taxa are important determinants of the post-dam removal community, and that the post-dam-removal BMI community continues to be in a state of reorganization. Full article

(This article belongs to the Special Issue Integrating Ecohydraulics in River Restoration: Advances in Science and Applications)

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21 pages, 5127 KiB

Open AccessArticle

Conceptual Approach for Positioning of Fish Guidance Structures Using CFD and Expert Knowledge

by Linus Feigenwinter, David F. Vetsch, Stephan Kammerer, Carl Robert Kriewitz and Robert M. Boes

Sustainability 2019, 11(6), 1646; https://doi.org/10.3390/su11061646 - 19 Mar 2019

Cited by 9 | Viewed by 4205

Abstract

The longitudinal connectivity of many rivers is interrupted by man-made barriers preventing the up- and downstream migration of fishes. For example, dams, weirs, and hydropower plants (HPP) are insuperable obstructions for upstream migration if no special measures like fish passes are put into effect. While upstream fishways have been implemented successfully and are still being optimized, the focus of current research is more and more on effective fish protection and guiding devices for downstream migration. According to current knowledge fish guidance structures (FGS) have a high potential in supporting the downstream migration by leading fishes to a bypass as an alternative to turbine passage. This work presents a structured and straightforward approach for the evaluation of potential locations of FGS combining traditional dimensioning principles with computational fluid dynamics (CFD) and novel findings from etho-hydraulic research. The approach is based on three key aspects: fish fauna, structural conditions, and hydraulic conditions, and includes three assessment criteria, which are used in an iterative process to define potential FGS locations. The hydraulic conditions can be investigated by means of hydrodynamic 3D simulations and evaluated at cross sections of potential FGS positions. Considering fundamentals of fish biology and ethology allows for rating of the flow conditions and thus for a suitability assessment of various locations. The advantage of the proposed procedure is the possibility to assess FGS configurations without implementing the FGS in the numerical model, thus limiting the computational expense. Furthermore, the implementation of various operation conditions is straightforward. The conceptual approach is illustrated and discussed by means of a case study. Full article

(This article belongs to the Special Issue Integrating Ecohydraulics in River Restoration: Advances in Science and Applications)

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20 pages, 5672 KiB

Open AccessArticle

Ecohydraulic Modelling to Support Fish Habitat Restoration Measures

by Ana Adeva-Bustos, Knut Alfredsen, Hans-Petter Fjeldstad and Kenneth Ottosson

Sustainability 2019, 11(5), 1500; https://doi.org/10.3390/su11051500 - 12 Mar 2019

Cited by 10 | Viewed by 4332

Abstract

Despite that hydromorphological restoration projects have been implemented since the 1940s, the key to improve the effectiveness of future restoration measures remains a challenge. This is in part related to the lack of adequate aims and objectives together with our limitations in understanding the effects on the physical habitat and ecosystems from interventions. This study shows the potential of using remote sensing techniques combined with hydraulic modelling to evaluate the success of physical restoration measures using habitat suitability as a quantifiable objective. Airborne light detection and ranging (LiDAR) was used to build a high-resolution two-dimensional model for Ljungan River, Sweden, using HEC-RAS 5.0. Two types of instream restoration measures were simulated according to the physical measures carried out in the river to improve salmonid habitat: (a) stones and rocks were moved from the bank sides to the main channel, and (b) a concrete wall was broken to open two channels to connect a side channel with the main river. Results showed that the hydraulic model could potentially be used to simulate the hydraulic conditions before and after instream modifications were implemented. A general improvement was found for the potential suitable habitat based on depth, velocity and shear stress values after the instream measures. Full article

(This article belongs to the Special Issue Integrating Ecohydraulics in River Restoration: Advances in Science and Applications)

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10 pages, 1377 KiB

Open AccessEditor’s ChoiceArticle

Passage Performance of Potamodromous Cyprinids over an Experimental Low-Head Ramped Weir: The Effect of Ramp Length and Slope

by Susana Dias Amaral, Paulo Branco, Christos Katopodis, Maria Teresa Ferreira, António Nascimento Pinheiro and José Maria Santos

Sustainability 2019, 11(5), 1456; https://doi.org/10.3390/su11051456 - 09 Mar 2019

Cited by 12 | Viewed by 3012

Abstract

Low-head ramped weirs are a common instream obstacle to fish movements. Fish passability of these structures, where water passes over but does not generate a waterfall, is primarily related to ramp length and slope, but their relative contribution has seldom been considered. This study aims to assess the passage performance of a potamodromous cyprinid, the Iberian barbel (Luciobarbus bocagei), negotiating an experimental ramped weir with varying ramp length (L) and slope (S). Four configurations were tested, with a constant discharge of 110 L∙s⁻¹. Results suggest that both factors influenced passage performance of fish. Attraction efficiency (AE) increased with increasing L and S, whereas the number of successes (N) and passage efficiency (PE) decreased upon increasing L. For S, it was found that both N and PE peaked at the intermediate level (20%). These results suggest that configurations with the lowest slopes may not necessarily be the best option because they may be less attractive for the fish and their demand for space is higher. Higher slopes (but not excessive) could be more attractive to fish, less space-demanding, and therefore, more cost-effective. Future studies should investigate how discharge and boulder placement influence fish passage across ramped weirs, to improve habitat connectivity. Full article

(This article belongs to the Special Issue Integrating Ecohydraulics in River Restoration: Advances in Science and Applications)

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11 pages, 1070 KiB

Open AccessArticle

Repulsive Effect of Stroboscopic Light Barriers on Native Salmonid (Salmo trutta) and Cyprinid (Pseudochondrostoma duriense and Luciobarbus bocagei) Species of Iberia

by Joaquim Jesus, Amílcar Teixeira, Silvestre Natário and Rui Cortes

Sustainability 2019, 11(5), 1332; https://doi.org/10.3390/su11051332 - 04 Mar 2019

Cited by 10 | Viewed by 2935

Abstract

A repulsive effect, that some induced primary stimuli, like sound and light, is known to be provoked in fish behavior. In the present study, two strobe light frequencies, 350 flashes/minute and 600 flashes/minute, were tested in laboratorial conditions, using three native freshwater fish species of northern Portugal: Brown trout (Salmo trutta), Northern straight-mouth nase (Pseudochondrostoma duriense) and Iberian barbel (Luciobarbus bocagei). The results showed a differential repulsive behavior of the fish species to light stimulus, and particularly to a frequency of 600 flashes/minute. S. trutta presented the most repulsive behavior, whereas the L. bocagei showed less repulsion to the light stimulus. No relevant differences were found between pre-test and post-assessments, confirming a rapid recovery of natural fish behavior after the deterrent effect. The results highlighted the potential of behavioral barriers, particularly in salmonid streams, based on strobe light stimulus. Full article

(This article belongs to the Special Issue Integrating Ecohydraulics in River Restoration: Advances in Science and Applications)

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13 pages, 1631 KiB

Open AccessArticle

Effects of Substrate on Movement Patterns and Behavior of Stream Fish through Culverts: An Experimental Approach

by Kyla Johnson, Lindsay E. Wait, Suzanne K. Monk, Russell Rader, Rollin H. Hotchkiss and Mark C. Belk

Sustainability 2019, 11(2), 470; https://doi.org/10.3390/su11020470 - 17 Jan 2019

Cited by 14 | Viewed by 2901

Abstract

Culverts can provide a significant barrier to fish passage by fragmenting fish habitats and impeding the passage success of small-bodied fish. Geographical connectivity is critical to the maintenance of diverse fish assemblages. Culverts with high cross-sectional velocity can cause population fragmentation by impeding passage of small, freshwater fish. Behavioral responses of small fish to high velocities can differ among functional groups, and swimming behavior of many species is not well known. We tested effects of substrate type on swimming behavior in two small, freshwater fish species—southern leatherside chub (Lepidomeda aliciae, a midwater species), and longnose dace (Rhinichthys cataractae, a benthic species)—across three substrate treatments: (1) a bare flume, (2) large flow obstacles, and (3) a natural cobble substrate. Both longnose dace and southern leatherside chub used paths of low velocity and swam in the near-substrate boundary area. Fish in the bare flume and large obstacle treatments swam along the corners of the flume in a straight swim path, whereas fish in the natural substrate treatment used all parts of the flume bed. There was no relationship between passage success of fish and substrate type, fish species, or their interaction. In contrast, substrate type, fish species, and their interaction were significant predictors of passage time. Southern leatherside chub passed through the test section about two to four times faster than longnose dace. Both species took longer to pass through the large flow obstacle treatment compared to the bare flume or natural substrate. The natural substrate created a complex velocity profile with areas of low velocity throughout the entire flume, in contrast to the other two treatments. Our data suggest natural substrates can improve the passage of small fish in high-velocity culverts for both benthic and midwater functional groups. Full article

(This article belongs to the Special Issue Integrating Ecohydraulics in River Restoration: Advances in Science and Applications)

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16 pages, 3619 KiB

Open AccessArticle

Conversion of Vertical Slot Fishways to Deep Slot Fishways to Maintain Operation during Low Flows: Implications for Hydrodynamics

by Luís Pena, Jerónimo Puertas, María Bermúdez, Luis Cea and Enrique Peña

Sustainability 2018, 10(7), 2406; https://doi.org/10.3390/su10072406 - 10 Jul 2018

Cited by 8 | Viewed by 3175

Abstract

Deep slot fishways (DSF) are similar to vertical slot fishways (VSF) except that a sill has been placed at the base of the slot, and thus require a lower discharge to operate. The conversion of a VSF to a DSF, which requires minimal design modifications, can make for a more flexible design in inflow management, maintaining the correct operation of the fishway in periods of limited water availability. It is, however, crucial to understand the new flow conditions that will be created inside the fishway, and their implications for fish passage. In this paper, the hydrodynamics of DSF were studied for two different pool configurations and five sill heights. The investigation comprised the analysis of the water surface configuration, the velocity and turbulence fields, as well as the definition of the equations that related discharges to depths in the pools. The DSF designs compared well in terms of water surface patterns and maximum velocities with VSFs, but resulted in a more complex three-dimensional flow pattern and increased turbulence levels. Further testing with fish is needed to analyze whether the benefits of retrofitting a VSF by adding a sill during low flows are cancelled out by increased fish passage difficulty. Full article

(This article belongs to the Special Issue Integrating Ecohydraulics in River Restoration: Advances in Science and Applications)

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Review

Jump to: Research

17 pages, 798 KiB

Open AccessEditor’s ChoiceReview

Life Stage-Specific Hydropeaking Flow Rules

by Daniel S. Hayes, Miguel Moreira, Isabel Boavida, Melanie Haslauer, Günther Unfer, Bernhard Zeiringer, Franz Greimel, Stefan Auer, Teresa Ferreira and Stefan Schmutz

Sustainability 2019, 11(6), 1547; https://doi.org/10.3390/su11061547 - 14 Mar 2019

Cited by 51 | Viewed by 7566

Abstract

Peak-operating hydropower plants are usually the energy grid’s backbone by providing flexible energy production. At the same time, hydropeaking operations are considered one of the most adverse impacts on rivers, whereby aquatic organisms and their life-history stages can be affected in many ways. Therefore, we propose specific seasonal regulations to protect ecologically sensitive life cycle stages. By reviewing hydropeaking literature, we establish a framework for hydrological mitigation based on life-history stages of salmonid fish and their relationship with key parameters of the hydrograph. During migration and spawning, flows should be kept relatively stable, and a flow cap should be implemented to prevent the dewatering of spawning grounds during intragravel life stages. While eggs may be comparably tolerant to dewatering, post-hatch stages are very vulnerable, which calls for minimizing or eliminating the duration of drawdown situations and providing adequate minimum flows. Especially emerging fry are extremely sensitive to flow fluctuations. As fish then grow in size, they become less vulnerable. Therefore, an ‘emergence window’, where stringent thresholds on ramping rates are enforced, is proposed. Furthermore, time of day, morphology, and temperature changes must be considered as they may interact with hydropeaking. We conclude that the presented mitigation framework can aid the environmental enhancement of hydropeaking rivers while maintaining flexible energy production. Full article

(This article belongs to the Special Issue Integrating Ecohydraulics in River Restoration: Advances in Science and Applications)

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