River Rehabilitation Research Articles

Determination of the Satisfaction Level of the Local People Benefiting from Murat River Rehabilitation Project (Bingöl, Elâzığ, and Muş Microcatchment Sample)

This research was conducted to determine the satisfaction level of the local people benefiting from the projects implemented in the microcatchments of Bingol, Elâzığ and Muş provinces. The primary data of the survey are the focus group interviews (FG) and key informative interviews (KI) conducted in the selected villages between the fdates 16-25 August 2021. According to the research results, the participants are generally satisfied with the project activities and that 62.2% of the local people have participated in the project activities during the past year. The results of the compatibility analysis show that the project had a positive impact on finding a job or improving working conditions among the locals with higher and equal incomes, while it had a negative impact among the locals with lower incomes. The impact of the project on improving employment or working conditions was positive for ranchers and those who farmed land for sale. Those who farm land for subsistence, not grow high-value crops, and cannot increase productivity indicated that the project had a negative impact on finding a job or improving working conditions. The impact of the project on finding jobs or improving the working conditions of the middle class living in Bingol and Elazığ was positive. The impact of the project on the poor local people in Muş on finding a job or improving their working conditions was negative. Within the framework of all information, it has been concluded that the project is an important source of development for the region and that this level of progress will emerge more clearly in the coming years.

Linking functional habitat and fish population dynamics modeling to improve river rehabilitation planning and assessment

In-stream habitat enhancement is widely used to improve ecological conditions in rivers, often prioritizing key fish life stages such as spawning and juvenile development. However, no standard approaches exist to predict their effects on fish recruitment and populations. Here, we use a spatially-explicit population dynamics model that integrates functional habitat dynamics to assess the impact of two rehabilitation measures in a hydropower-impacted section of the Inn River (SE Germany) on the recruitment potential of four rheophilic and lithophilic fish species — grayling, nase, barbel, and chub. Rehabilitation measures implemented included the construction of a bypass channel and an island side-channel system to improve both longitudinal connectivity and habitat conditions. In addition, we analyzed two alternatives, which would enhance functional availability of nursery habitats from actual 33.2% to 66.8% and 95.3%, respectively. The results suggest that the improved habitat conditions will yield on average additional 14.9 individuals/ha (5.6 kg/ha) of the target species. However, the limited accessibility of usable nursery habitat constitutes a significant recruitment bottleneck for all species. In the alternative scenarios, the increase of functional connectivity will result in average densities of 17.9 and 25.8 individuals/ha, respectively. However, potential further improvements are species-specific, because of distinct population responses to spawning-to-nursery habitat ratios, with density changes varying between -11.7% for grayling and +172.6% for chub. This study not only demonstrates the applicability of the modeling approach for assessing and planning rehabilitation measures but also emphasizes the importance of considering habitat ratios and their functional connectivity to optimize recruitment potential.

Integrating UAV‐Based Topographic and Geomorphic Analysis for the Development of River Rehabilitation Plans in Semi‐Urban Settings

Integrating <scp>UAV</scp>‐Based Topographic and Geomorphic Analysis for the Development of River Rehabilitation Plans in Semi‐Urban Settings

Eksplorasi program lingkungan hijau sebagai upaya pengurangan pencemaran lingkungan laut di Kota Pasuruan

Pencemaran laut adalah masalah serius bagi banyak kota pesisir, termasuk Kota Pasuruan, yang berdampak negatif pada lingkungan laut, kesehatan manusia, dan ekonomi lokal. Penelitian ini mengevaluasi efektivitas program lingkungan hijau untuk mengurangi pencemaran laut di Pasuruan. Metode kualitatif digunakan dengan wawancara mendalam, observasi, dan analisis dokumen terkait. Informan kunci adalah pejabat pemerintah, anggota komunitas, dan aktivis lingkungan. Hasil penelitian menunjukkan bahwa program lingkungan hijau, seperti kampanye pengelolaan sampah, penanaman mangrove, rehabilitasi sungai, dan promosi gaya hidup ramah lingkungan, berhasil mengurangi pencemaran laut dan meningkatkan kesadaran masyarakat. Namun, tantangan seperti kurangnya anggaran, partisipasi masyarakat, dan pemahaman tentang konservasi lingkungan masih ada. Rekomendasi untuk keberlanjutan program mencakup peningkatan pendanaan, pelibatan aktif masyarakat, dan pendidikan lingkungan. Secara keseluruhan, program lingkungan hijau berpotensi besar mengurangi pencemaran laut di Pasuruan, tetapi diperlukan kerjasama dari pemerintah, masyarakat, dan pemangku kepentingan lainnya untuk memastikan keberhasilan jangka panjangnya.

The Role of Watershed Management Board in the Rehabilitation of Butuanon River Watershed in Cebu, Philippines

This study was conducted to assess the role of Butuanon River Watershed Management Board (BRWMB) in rehabilitating the Butuanon River in Cebu, Philippines. Data was gathered through key informant interviews with officials of the Board and a self-administered questionnaire for the members of the Board and was analyzed through descriptive and thematic analyses. Results showed that since the creation of the Butuanon River Watershed Water Quality Management Area (BRW WQMA) in 2014, the river's biological oxygen demand (BOD) level has decreased. While the level has yet to meet the water quality guidelines of DENR's Class D rivers, the Board's initiatives like clean-up activities, information, education, and communication (IEC), and the relocation of informal settlers residing at riverbanks contributed to the improvement of the river's water quality. The activities conducted by the Board strengthened the linkages with other stakeholders. The good working relationship among the stakeholders facilitated the convergence of their resources, making their efforts to rehabilitate the Butuanon River more coordinated and sustainable. Furthermore, Mandaue LGU, the chair of BRWMB, integrated its efforts in its Comprehensive Land Use Plan (CLUP) and the 10-year Action Plan of the BRW WQMA in its Butuanon River Rehabilitation Plan. Results revealed that the existence of BRWMB played a vital role in the Butuanon River's rehabilitation, and such efforts are hoped to be sustained with the participation of the various stakeholders and formulation of policies to support all efforts of the Board.

Biotic and dragonfly diversity indices as ecological quality evaluation in Lahat District Rivers, South Sumatra, Indonesia

Abstract. Rachmawati A, Yustian I, Pujiastuti Y, Suparman Shk, Arinafril. 2023. Biotic and dragonfly diversity indices as ecological quality evaluation in Lahat District Rivers, South Sumatra, Indonesia. Biodiversitas 24: 6059-6068. The Lematang, Sandaran, and Kungkilan rivers have been reported to be polluted by coal mining activities. This study aimed to evaluate the ecological conditions using a dragonfly as a bio-indicator. Dragonfly surveys were conducted using direct observation procedures in 11 research sites determined by purposive sampling based on positions of the upstream, midstream and downstream of the river entering the coal mining area, including settling ponds managing waste from post-mining activities (stockpiles and disposal). Dragonflies were captured by visual observations, direct capture, and sticky traps. Data were analyzed by calculating the Dragonfly Biotic Index (DBI) and Diversity Index. The correlation between dragonflies and environmental factors was analyzed using Canonical Correspondence Analysis (CCA) according to Jaccard’s index. The results showed there were 23 species of dragonflies. Larvae and exuviae were found in Aeshnidae and Libellulidae families. Dragonfly species with the highest DBI values were seen in Rhyothemis triangularis, Tholymis tillarga, Zyxomma petiolatum, Atrocalopteryx atrata, Libellago lineata and Rhinocypha fenestrata. Sandaran River had the highest DBI value and diversity index because of the undisturbed condition of the area, which had natural vegetation and unpolluted water conditions. The Kungkilan River will become the focus of river rehabilitation, starting with the reclamation of the river riparian area.

Hybridity and Multiscale Compatibility in Landscape Infrastructure for Mountain River Restoration: A Pathway Toward Environmental and Socio-Ecological Sustainability

River rehabilitation has traditionally focused on hard-engineering projects, which often fail to address environmental protection concerns and social-ecological services in a larger territorial context. In particular, mountain rivers pose unique challenges due to their diverse hydrological and morphological conditions, which are often overlooked by traditional restoration methods. Consequently, water quality deteriorates and social-ecological imbalances arise. To address these challenges, we propose a holistic solution that integrates landscape infrastructure (LI), a soft-engineered biophysical structure and process. Our approach combines hydrological analysis, ecological sensitivity assessment, and ecological design solutions to develop an LI framework for the Xiaojiahe basin in the Chongqing Mountain range in southwest China. This framework emphasizes integration across the spatial scale of landscape networks and corridors. Our study reveals the existence of fragmented river systems and limited connectivity among green spaces in the research area. The adoption of a comprehensive Landscape Infrastructure (LI) framework facilitates the execution of culturally sensitive and practical design solutions for Mountain Urban River Restoration (MURR) at different levels. This approach reinstates the multifaceted environmental and socio-ecological benefits of the basin. We believe that our approach can be applied to other cases with similar contexts and challenges.

Influence of spur dike’s angle on sand bar formation in a rectangular channel

Spur dike is one of the various technologies utilized in river rehabilitation. Spur dike provides many advantages, such as promoting aquatic habitat, improving channel for navigation, and protecting the stream banks. This study serves to evaluate the effect of a spur dike on the formation of sand bars in a straight rectangular channel fed by suspended sediment. The performance of spur dike in inducing the formation of spur dike is investigated under three different spur dike angles. A three-dimensional (3D) model was developed using Flow-3D® to investigate the flow depth and velocity around spur dike. Based on the velocity distribution, the influence of spur dike angle on the formation of sand bar was explained. A scalar concentration is used to represent the suspended sediment in the simulation, and the formation of sand bar is represented by the scalar concentration. According to the numerical results, the 90° spur dike produced a larger and longer sand bar than the 45° and 135° spur dikes.

Why Consider Geomorphology in River Rehabilitation?

River rehabilitation and ecological engineering are becoming critical issues for improving river status when ecological habitats and connectivity have been altered by human pressures. Amongst the range of existing rehabilitation options, some specifically focus on rebuilding fluvial forms and improving physical processes. The aim of this contribution is to illustrate how geomorphological expertise and process-based thinking contribute to river rehabilitation success. This semantic contribution is intended to feed the rehabilitation debate, particularly concerning the design of actions and the proposed references for monitoring target reaches and evaluating rehabilitation effects empirically. This article is also based on lessons learned from practical cases, mainly in gravel-bed rivers. Geomorphic understanding is needed at a local level to achieve an adequate diagnosis of river functioning, estimate human impacts and potential remnant river responsiveness, and to assess the gains and risks from rehabilitation, as well as to appraise success or failure through several pre- and post-project assessment strategies. Geomorphological studies can also be upscaled in a top-down manner (from high-order controls to small-scale processes, understanding detailed processes in their regional or basin-wide context), providing large-scale information at the regional, national, or even global level, information that can be used to diagnose the health of riverscapes in relation to local site-specific contexts. As such, geomorphological studies support strategic planning and prioritization of rehabilitation works according to specific contexts and river responsiveness, so as to move from opportunistic to objective-driven strategies.

Effects of downstream environmental flow release on enhancing the groundwater recharge and restoring the groundwater/surface-water connectivity in Yongding River, Beijing, China

The Yongding River (Beijing, China) was dry most times of the year, and groundwater storage was severely depleted. To address this issue, a river rehabilitation project was initiated. A downstream environmental flow release (EFR) project from upstream reservoirs has been implemented since 2019. This study evaluated the impact of EFR by constructing transient groundwater-flow and numerical tracer transport models to simulate the hydrogeological responses to the water release events in 2019–2020. The study identified two factors that significantly influence the river leakage rate, which are operational factors (i.e., water release rate and duration) and physical factors (i.e., hydraulic properties of the riverbed, regional hydraulic gradients, and groundwater depth) that determine the maximum water availability for groundwater recharge and maximum infiltration capacity, respectively. Predictive modelling was performed to assess the long-term effects of the proposed EFR scheme from 2021 to 2050, which showed that groundwater levels along the river will increase by 10–20 m by 2050. Groundwater storage is expected to be largely recovered and groundwater/surface-water connectivity in the middle reach of the river will be restored. This restoration will not only maintain the environmental flow for the benefit of ecosystems but also enhance groundwater recharge, promoting sustainable groundwater development in the region. Overall, this study provides valuable insights into the effectiveness of the proposed EFR scheme in achieving sustainable groundwater development in the region.

Short-Term Responses of Aquatic Ecosystem and Macroinvertebrate Assemblages to Rehabilitation Actions in Martil River (North-Western Morocco)

This study aimed to evaluate the effects of the Martil River rehabilitation project and recently constructed dam infrastructures to reduce flood risks and to promote local socio-economic development on the ecological integrity of the river. The assessment focused on changes in fluvial landforms over time and the evaluation of aquatic ecosystems based on six physicochemical parameters (temperature, pH, electrical conductivity, dissolved oxygen, biochemical oxygen demand, and chemical oxygen demand), morpho-hydrological variables (stream width, water depth, and current speed), habitat indices (QBR, IHF, and MQI), and macroinvertebrate assemblages of EPT, OCH, and Chironomidae (Diptera) at five stations from autumn 2015 to spring 2018 (prior to and during the rehabilitation actions). The results showed that the river rehabilitation project led to profound changes in Martil River’s ecosystem and water quality over time. Physicochemical and habitat measurements at the rehabilitated sites revealed a major change in macroinvertebrate communities due to changes in fluvial landforms in relation to flow-sediment regimes. As a result, some typical species of lentic habitats disappeared, while alien, opportunistic, and lotic species appeared.

Hazai kis folyók belterületi típusú rehabilitációs szakaszainak meghatározása

The aim of this research was to analyze and typify the location and spatial structure characteristics of river reaches within settlements. It also included the examination of the landscape, and the natural and geographical relationships of the specific types. In the case of urban river reaches, our research question was whether it may be necessary to include river sections outside the settlement’s legal urban boundary in the river rehabilitation. The subjects of the research were settlements with a population of over 5000, located along small rivers, of which there are a total of 39 in Hungary. As a result, we determined three main types based on the river’s position in the settlement structure. In the case of the urban river reaches, based on the examination of the updated CORINE land cover categories, we found that the rehabilitation could typically go further than the legal urban boundary, as we also explored river sections in the rural areas that are adjacent to areas of an urban character or recreational functions.

Quantifying ecosystem states and state transitions of the Upper Mississippi River System using topological data analysis.

Aquatic systems worldwide can exist in multiple ecosystem states (i.e., a recurring collection of biological and chemical attributes), and effectively characterizing multidimensionality will aid protection of desirable states and guide rehabilitation. The Upper Mississippi River System is composed of a large floodplain river system spanning 2200 km and multiple federal, state, tribal and local governmental units. Multiple ecosystem states may occur within the system, and characterization of the variables that define these ecosystem states could guide river rehabilitation. We coupled a long-term (30-year) highly dimensional water quality monitoring dataset with multiple topological data analysis (TDA) techniques to classify ecosystem states, identify state variables, and detect state transitions over 30 years in the river to guide conservation. Across the entire system, TDA identified five ecosystem states. State 1 was characterized by exceptionally clear, clean, and cold-water conditions typical of winter (i.e., a clear-water state); State 2 had the greatest range of environmental conditions and contained most the data (i.e., a status-quo state); and States 3, 4, and 5 had extremely high concentrations of suspended solids (i.e., turbid states, with State 5 as the most turbid). The TDA mapped clear patterns of the ecosystem states across several riverine navigation reaches and seasons that furthered ecological understanding. State variables were identified as suspended solids, chlorophyll a, and total phosphorus, which are also state variables of shallow lakes worldwide. The TDA change detection function showed short-term state transitions based on seasonality and episodic events, and provided evidence of gradual, long-term changes due to water quality improvements over three decades. These results can inform decision making and guide actions for regulatory and restoration agencies by assessing the status and trends of this important river and provide quantitative targets for state variables. The TDA change detection function may serve as a new tool for predicting the vulnerability to undesirable state transitions in this system and other ecosystems with sufficient data. Coupling ecosystem state concepts and TDA tools can be transferred to any ecosystem with large data to help classify states and understand their vulnerability to state transitions.

Fish Assemblages in the Penobscot River: A Decade after Dam Removal

AbstractThe Penobscot River Restoration Project in Maine was a large river rehabilitation project that culminated in the removal of the two lowermost dams and improvements to fish passage on several remaining dams. Fish assemblages were surveyed for 3 years prior to rehabilitation, 3 years after rehabilitation, and 8 years after rehabilitation. Approximately 475 km of shoreline were sampled via boat electrofishing, yielding 133,394 individual fish of 41 species. The greatest shifts in assemblage structure occurred immediately after dam removal in formerly impounded sections, with an increased prevalence of riverine and migratory species. Long‐term sampling documented changes within tributaries and tidally influenced river segments, where large schools of adult and young‐of‐the‐year alosines increased in abundance. Upstream of the lowermost dam, the river remains dominated by lacustrine species, while adult anadromous fishes continue to be most abundant immediately downstream of the lowermost dam. Our results provide increased evidence that dam removals result in altered fish assemblages, which are now dominated by riverine and anadromous species in previously impounded habitats. Alosines in the Penobscot River have exhibited the greatest long‐term response to river restoration efforts.

PUSAT EDUKASI SUNGAI KARANG MUMUS

Samarinda's Karang Mumus River Education Center is a river rehabilitation learning center conducted by the Komunitas Gerakan Memungut Sehelai Sampah (GMSS SKM). The purpose of GMSS isheld facilities to educate the public so as to restore the condition, function, use of the Karang Mumus River for a good and healthy environment and the welfare of the community, animals and natural living space. The program is carried out from socialization and community empowerment that will encourage the community, academics, and city migrants to care about the river environment. Through an ecological architectural approach that is expected so that the community can capture from the GMSS's objectives of seeing, understanding, increasing awareness for the environment, and having active actions in maintaining the river.

Strategic Design and Delivery of Integrated Catchment Restoration Monitoring: Emerging Lessons from a 12-Year Study in the UK

Despite growing interest in river and catchment restoration, including a focus on nature-based solutions, assessing effectiveness of restoration programmes continues to prove a challenge. The development of the Eddleston Water project, the Scottish Government’s empirical study of the impact of implementing natural flood management measures on flood risk and habitat restoration, provides the opportunity to review restoration monitoring at a strategic and operational level for this long-running catchment restoration programme. The project has implemented an extensive range of restoration measures along the river and across the 69 km2 catchment. This paper reviews the monitoring strategy and assesses both how the monitoring network developed meets its strategic aims and what subsequent changes were made in monitoring design and implementation. Covering hydrology, hydromorphology and ecology, we explore how all three are integrated to provide a comprehensive assessment of restoration success. Lessons to help inform other river rehabilitation monitoring programmes include the importance of a scoping study and capturing the full range of environmental variables pre-restoration; the limitations of BACI designs; and the need to focus integrated monitoring on a process-based framework and impact cascade, whilst also covering the full trajectory of recovery.

Rehabilitating Valley Floors to a Stage 0 Condition: A Synthesis of Opening Outcomes

Degraded floodplains and valley floors are restored with the goal of enhancing habitat for native fish and aquatic-riparian biota and the protection or improvement of water quality. Recent years have seen a shift toward “process-based restoration” that is intended to reestablish compromised ecogeomorphic processes resulting from site- or watershed-scale degradation. One form of process-based restoration has developed in the Pacific Northwest, United States, that is intended to reconnect rivers to their floodplains by slowing down flows of sediment, water, and nutrients to encourage lateral and vertical connectivity at base flows, facilitating development of dynamic, self-forming, and self-sustaining river-wetland corridors. Synergies between applied practices and the theoretical work of Cluer and Thorne in 2014 have led this form of restoration to be referred to regionally as restoration to a Stage 0 condition. This approach to rehabilitation is valley scale, rendering traditional monitoring strategies that target single-thread channels inadequate to capture pre- and post-project site conditions, thus motivating the development of novel monitoring approaches. We present a specific definition of this new type of rehabilitation that was developed in collaborative workshops with practitioners of the approach. Further, we present an initial synthesis of results from monitoring activities that provide a foundation for understanding the effects of this approach of river rehabilitation on substrate composition, depth to groundwater, water temperature, macroinvertebrate richness and abundance, secondary macroinvertebrate production, vegetation conditions, wood loading and configuration, water inundation, flow velocity, modeled juvenile salmonid habitat, and aquatic biodiversity.

Agroforestry Contributions to Urban River Rehabilitation

The context of urban rivers is one of pollution of their courses, the degradation of riparian habitats, the loss of biodiversity, and the marginalization of the human populations that live next to them. Due to urban growth, the hydrological dynamics in entire basins and the hydromorphology of rivers are changing. This situation increases flooding, decreases the availability of water for human use, and disconnects the rivers from the dynamics of the city. Agroforestry is the integration of cultural, wild, and domesticated diversity with use, conservation, and restoration objectives. These practices in cities can contribute to addressing the problems mentioned. We analyze agroforestry practices and the socio-ecological contributions to urban river rehabilitation. We review 37 experiences worldwide. Agroforestry practices included in the review are trees and hedgerows; wetland agroforestry; aquatic, botanical, edible, educational, and rain gardens; bioswales; green parking lots; food forestry; vegetation in alleys and streets; vertical terrace walls, among others. Agroforestry contributes to efforts to solve urban river problems, improve water quality and access, restore riparian habitats, enhance river hydromorphology, support local economies, and create a river culture. We emphasize promoting multi-relational people–river interactions based on theoretical and practical frameworks that integrate diverse disciplines, perspectives, and experiences.

A Positive Attitude Practice: The Best Solution to Mitigate Water Pollution

The attitude of human create pollution. Pollution has to be addressed, and changing of human attitudes could be the only way to mitigate the pollution. The three pillars method to encourage humans to change their attitude so that our environment will at least maintain the strata quo of the current situation. The process of changing the human attitude is a long-term and time- consuming process, however, the end result is an encouraging one. The two examples quoted are the River of Life Project and the Sungai Way River rehabilitation project. Both projects have significant success stories of changing human attitudes. The first example is that the government has spent a lot of money to beautify and clean the river, an expensive clean-up, but it creates an awareness that is time for humans need to change their attitude to keep the environment clean (the application of Utilitarian attitude approach). The second example is the involvement of stakeholders, such as communities, students, teachers, merchants, factory owners, and traders. Who are knees to rehabilitate the river that flows beside their place of work, properties, residential area, schools, and playground (a good application of Normative Attitude). The environment can be reinstated to its natural state when humans change their attitude of habituation.

Sediment Augmentation for River Rehabilitation and Management—A Review

Sediment management is an important part of river rehabilitation and management. Global case studies provide a growing number of examples of successful sediment augmentation measures that can counter the adverse effects of disturbed sediment regimes. The initial river state and the objectives of the reported measures can vary largely, however. In this review, a summary of selected case studies is presented, and an objective-focused classification of sediment augmentation measures is introduced. Case-specific restrictions, design approaches and assessment methods based on the literature review and our own experience from working in the field are presented. This summary aims to provide an overview on up-to-date knowledge for applied river rehabilitation and management.