Periodic Reporting for period 1 - HydroCORE (Hydropower infrastructure in Andean headwaters: Combining Observations and Remote sensing to analyse Environmental impacts)
Okres sprawozdawczy: 2023-07-01 do 2025-06-30
These days, many of us rely heavily on the continuous availability of electricity and we have a hard time imagining how our lives would be without it. This dependency comes at an inconvenient environmental cost, as the burning of fossil fuels increases the level of carbon dioxide in the atmosphere. This continuous discharge of carbon dioxide (and other associated gases) strengthens the greenhouse effect of the atmosphere, which leads to globally higher temperatures and underlies various changes in regional climate conditions. Unfortunately, even the combination of existing awareness and scientific proof on the link between carbon dioxide emissions and climate change has failed to turn the tide, with few promises being actually implemented to effectively reduce emissions.
Nevertheless, the reduction of greenhouse gas emissions remains the main aim of the ongoing transition to more sustainable and efficient energy sources. Hydropower is a well-known and popular alternative to the burning of fossil fuels due to its simplicity and relatively low cost, contributing a significant fraction (up to 50 %) of the total amount of electricity generated in Latin America. Unfortunately, also hydropower installations are associated with environmental impacts at a wide spatial and temporal range. More specifically, the following impacts can be identified: ecosystem fragmentation (e.g. acting as a migration barrier for fish), hydrological alteration (e.g. reducing peak flows), biogeochemical disturbance (e.g. increased nutrient cycling within the reservoir), sediment trapping, socio-economic impacts, and greenhouse gas emissions. In short, even though hydropower is considered to be a sustainable energy source, there are certain environmental impacts that should be considered.
Globally, more than 38,000 dams have been constructed and additional damming is bound to irreversibly impact highly diverse systems such as the Amazon and Congo basins, causing the extinction of many freshwater species. Within the Amazon basin, large hydropower installations have substantially altered the hydrological regime of several tributaries, while headwaters have mostly been dammed for relatively small (< 50 MW) hydropower installations. Yet, by transporting nutrients and minerals, these Andean headwaters support extensive productive corridors and control numerous natural systems in the Amazonian lowlands. With several large dams (> 1000 MW) being planned within these headwaters and hydrological patterns changing due to melting glaciers and altered precipitation patterns, Andean communities and ecosystems are at significant risk of experiencing reductions in water supply, especially in regions with a high degree of urbanisation. As such, hydropower generation balances on the crossroads between energy provision, water availability, and ecological functioning.
The HydroCORE project starts from the notice that hydropower infrastructure impacts the environment and uses this as a basis to perform its activities, while using the Paute river basin in the Azuay province (Ecuador) as study area. The focus is directed towards local impacts through the study of abiotic (e.g. flow pattern, erosion, chemical profile) and biotic (e.g. macroinvertebrate assemblage) characteristics and extends towards more global influences (e.g. potential emission of carbon dioxide). As a result, the project entails a combined approach of fieldwork, remote sensing, and modelling to bring different data sources and insights together. Ultimately, the objective is to illustrate impacts associated with hydropower infrastructure and suggest mitigating measures aiming to directly improve environmental health and operational productivity. Indirectly, this will benefit human well-being through a better management of water resources and a reduced contribution to climate change.
In order to reach the abovementioned objectives and generate impact, various activities are planned and their mutual timing is of utmost importance. First of all, the collection of data through field observations is an essential element of the HydroCORE project and determines when other project-related activities can be scheduled. Fieldwork is foreseen every three months to collect information on the physicochemical conditions and greenhouse gas emissions, starting in the first month of the project to allow for sufficient time towards the end of the outgoing phase. In addition, fieldwork is foreseen every six months to collect information on the macroinvertebrate community, starting together with the first abiotic campaign. A total of three weeks per abiotic campaign and two months per combined campaign are planned. During the first year, the time between field campaigns is allocated to the development of a hydrological model (including data collection). Similarly, the time between field campaigns during the second year is allocated to applying the developed model through simulations. During the return phase, time is foreseen to acquire the necessary skills to use remote sensing for assessing morphological changes and greenhouse gas emissions. The remainder of the time is allocated to data analysis, outreach activities (including publications and seminars), and personal training.
Nevertheless, the reduction of greenhouse gas emissions remains the main aim of the ongoing transition to more sustainable and efficient energy sources. Hydropower is a well-known and popular alternative to the burning of fossil fuels due to its simplicity and relatively low cost, contributing a significant fraction (up to 50 %) of the total amount of electricity generated in Latin America. Unfortunately, also hydropower installations are associated with environmental impacts at a wide spatial and temporal range. More specifically, the following impacts can be identified: ecosystem fragmentation (e.g. acting as a migration barrier for fish), hydrological alteration (e.g. reducing peak flows), biogeochemical disturbance (e.g. increased nutrient cycling within the reservoir), sediment trapping, socio-economic impacts, and greenhouse gas emissions. In short, even though hydropower is considered to be a sustainable energy source, there are certain environmental impacts that should be considered.
Globally, more than 38,000 dams have been constructed and additional damming is bound to irreversibly impact highly diverse systems such as the Amazon and Congo basins, causing the extinction of many freshwater species. Within the Amazon basin, large hydropower installations have substantially altered the hydrological regime of several tributaries, while headwaters have mostly been dammed for relatively small (< 50 MW) hydropower installations. Yet, by transporting nutrients and minerals, these Andean headwaters support extensive productive corridors and control numerous natural systems in the Amazonian lowlands. With several large dams (> 1000 MW) being planned within these headwaters and hydrological patterns changing due to melting glaciers and altered precipitation patterns, Andean communities and ecosystems are at significant risk of experiencing reductions in water supply, especially in regions with a high degree of urbanisation. As such, hydropower generation balances on the crossroads between energy provision, water availability, and ecological functioning.
The HydroCORE project starts from the notice that hydropower infrastructure impacts the environment and uses this as a basis to perform its activities, while using the Paute river basin in the Azuay province (Ecuador) as study area. The focus is directed towards local impacts through the study of abiotic (e.g. flow pattern, erosion, chemical profile) and biotic (e.g. macroinvertebrate assemblage) characteristics and extends towards more global influences (e.g. potential emission of carbon dioxide). As a result, the project entails a combined approach of fieldwork, remote sensing, and modelling to bring different data sources and insights together. Ultimately, the objective is to illustrate impacts associated with hydropower infrastructure and suggest mitigating measures aiming to directly improve environmental health and operational productivity. Indirectly, this will benefit human well-being through a better management of water resources and a reduced contribution to climate change.
In order to reach the abovementioned objectives and generate impact, various activities are planned and their mutual timing is of utmost importance. First of all, the collection of data through field observations is an essential element of the HydroCORE project and determines when other project-related activities can be scheduled. Fieldwork is foreseen every three months to collect information on the physicochemical conditions and greenhouse gas emissions, starting in the first month of the project to allow for sufficient time towards the end of the outgoing phase. In addition, fieldwork is foreseen every six months to collect information on the macroinvertebrate community, starting together with the first abiotic campaign. A total of three weeks per abiotic campaign and two months per combined campaign are planned. During the first year, the time between field campaigns is allocated to the development of a hydrological model (including data collection). Similarly, the time between field campaigns during the second year is allocated to applying the developed model through simulations. During the return phase, time is foreseen to acquire the necessary skills to use remote sensing for assessing morphological changes and greenhouse gas emissions. The remainder of the time is allocated to data analysis, outreach activities (including publications and seminars), and personal training.
The scientific activities of the HydroCORE project can be grouped into three main categories: (1) data collection and analysis, (2) hydrological model development, and (3) hydrological simulations. During the outgoing phase, attention was directed at the collection of data and the development of a hydrological model.
Data collection is an important part of scientific research and the HydroCORE project is no exception. To support the intended activities, three main sources of data were identified: (1) project-specific fieldwork, (2) data from external sources, and (3) data obtained through remote sensing. Fieldwork was successfully implemented during the outgoing phase and consisted of the selection of 50 sampling sites, divided over rivers (30) and reservoirs (20). Sites were visited eight times (every three months) to register physicochemical conditions (including temperature, conductivity, oxygen levels, pH, turbidity, organic carbon, nitrogen, and phosphorus), update habitat composition (including substrate type, vegetation, surrounding land use, and many more), and sample greenhouse gases (including fluxes and dissolved levels). The number of sample sites varied slightly between campaigns and not all locations could be sampled during each campaign due to low water levels within the reservoirs, resulting in the selection of an alternative set of sampling sites. Our results show that the city of Cuenca has a clear negative impact on the abiotic conditions of (1) the river passing through it and (2) the (start of) the first reservoir downstream of Cuenca. Hence, reducing the impact of the city will also reduce the impact of the reservoir on the abiotic conditions within the water column. Similar observations are expected from the biotic samples and greenhouse gas analyses, though those datasets are currently not yet finalised (expected by the end of August 2025). Data from external sources showed to be more difficult to obtain, after requesting hydrological and meteorological data from both INAMHI (National Institute for Meteorology and Hydrology) and CELEC (Electricity corporation of Ecuador). It took several months to obtain all the requested data from INAMHI, while no official data from CELEC has been obtained up to this point. Two alternative options were considered when this showed to become a challenge: (1) use archived data from previous projects and (2) use data from remote sensing. Archived data was available and distributed over various files and folders, yet displaying different time series for the same station. This was considered better than having no data at all, though still caused an overall delay of the development of a hydrological model significantly (see further). In the meantime, attention was also directed at the collection of data through remote sensing. Several platforms provide satellite-derived data and often in various formats, which brought an extra challenge to automatically read and summarise the relevant data through R-scripts. At the end of the outgoing phase, functional scripts for the analysis of precipitation data from the Copernicus and CHRS platforms are available. Yet, our comparative analyses between precipitation data from INAMHI and data from INAMHI showed that both series are not interchangeable and that satellite-based precipitation data cannot be used as a one-on-one replacement for ground-based precipitation.
As indicated above, a significant delay in the development of the hydrological model took place due to the (administrative) difficulties encountered when requesting data from external institutions. While building the first time series from the archived data, the basis for the hydrological model was developed through the use of QGIS and the SWAT+ plug-in. The necessary raster and shape files were identified and used to derive the complete basin, the different sub-basins, the (simplified) channel structure, and the location of the reservoirs. As such, a functional hydrological model for the Paute basin and including the two main reservoirs has been successfully developed, though the simulated outcome was not representative of the actual situation due to the parameters using their default values. Finally, the INAMHI data was obtained and used to derive the climate parameters necessary to steer the climate model and weather generator within SWAT+. Using these parameters clearly improved the performance of the hydrological model and further improvement is expected after optimising additional parameters related to land use, run-off characteristics, and losses to the soil. As a result, no simulations of future hydrological conditions have yet been performed.
In short, the following main achievements were obtained during the outgoing phase:
- Implementation of eight sampling campaigns
- Creating eight campaign-specific datasets
- Partial collection of external hydrological and meteorological data
- Development of a functional hydrological model
- Partial finetuning of climate parameters within the hydrological model
- Insight into the limited comparability of ground-based observations and satellite-based estimates of precipitation
Data collection is an important part of scientific research and the HydroCORE project is no exception. To support the intended activities, three main sources of data were identified: (1) project-specific fieldwork, (2) data from external sources, and (3) data obtained through remote sensing. Fieldwork was successfully implemented during the outgoing phase and consisted of the selection of 50 sampling sites, divided over rivers (30) and reservoirs (20). Sites were visited eight times (every three months) to register physicochemical conditions (including temperature, conductivity, oxygen levels, pH, turbidity, organic carbon, nitrogen, and phosphorus), update habitat composition (including substrate type, vegetation, surrounding land use, and many more), and sample greenhouse gases (including fluxes and dissolved levels). The number of sample sites varied slightly between campaigns and not all locations could be sampled during each campaign due to low water levels within the reservoirs, resulting in the selection of an alternative set of sampling sites. Our results show that the city of Cuenca has a clear negative impact on the abiotic conditions of (1) the river passing through it and (2) the (start of) the first reservoir downstream of Cuenca. Hence, reducing the impact of the city will also reduce the impact of the reservoir on the abiotic conditions within the water column. Similar observations are expected from the biotic samples and greenhouse gas analyses, though those datasets are currently not yet finalised (expected by the end of August 2025). Data from external sources showed to be more difficult to obtain, after requesting hydrological and meteorological data from both INAMHI (National Institute for Meteorology and Hydrology) and CELEC (Electricity corporation of Ecuador). It took several months to obtain all the requested data from INAMHI, while no official data from CELEC has been obtained up to this point. Two alternative options were considered when this showed to become a challenge: (1) use archived data from previous projects and (2) use data from remote sensing. Archived data was available and distributed over various files and folders, yet displaying different time series for the same station. This was considered better than having no data at all, though still caused an overall delay of the development of a hydrological model significantly (see further). In the meantime, attention was also directed at the collection of data through remote sensing. Several platforms provide satellite-derived data and often in various formats, which brought an extra challenge to automatically read and summarise the relevant data through R-scripts. At the end of the outgoing phase, functional scripts for the analysis of precipitation data from the Copernicus and CHRS platforms are available. Yet, our comparative analyses between precipitation data from INAMHI and data from INAMHI showed that both series are not interchangeable and that satellite-based precipitation data cannot be used as a one-on-one replacement for ground-based precipitation.
As indicated above, a significant delay in the development of the hydrological model took place due to the (administrative) difficulties encountered when requesting data from external institutions. While building the first time series from the archived data, the basis for the hydrological model was developed through the use of QGIS and the SWAT+ plug-in. The necessary raster and shape files were identified and used to derive the complete basin, the different sub-basins, the (simplified) channel structure, and the location of the reservoirs. As such, a functional hydrological model for the Paute basin and including the two main reservoirs has been successfully developed, though the simulated outcome was not representative of the actual situation due to the parameters using their default values. Finally, the INAMHI data was obtained and used to derive the climate parameters necessary to steer the climate model and weather generator within SWAT+. Using these parameters clearly improved the performance of the hydrological model and further improvement is expected after optimising additional parameters related to land use, run-off characteristics, and losses to the soil. As a result, no simulations of future hydrological conditions have yet been performed.
In short, the following main achievements were obtained during the outgoing phase:
- Implementation of eight sampling campaigns
- Creating eight campaign-specific datasets
- Partial collection of external hydrological and meteorological data
- Development of a functional hydrological model
- Partial finetuning of climate parameters within the hydrological model
- Insight into the limited comparability of ground-based observations and satellite-based estimates of precipitation
The HydroCORE project was planned in such a way that the outgoing phase was designed with data collection in mind, supplemented with the development of a hydrological model. No key results were expected, though smaller observations were considered possible. During the outgoing phase, it was observed that the urban area of Cuenca has a major impact on the river passing through it. More specifically, nutrient levels were clearly higher downstream of the city and even showed a conversion pathway for nitrogen. In addition, the most upstream part of the first reservoir (receiving the river coming from Cuenca) also showed a local upconcentration of the same nutrients, with a general decrease in the downstream direction. These are clear observations for local policy and decision makers to think about improved wastewater treatment to protect environmental health and reduce the associated greenhouse gas emissions. Moreover, these impacts were even more intense during dry periods in both the river and reservoirs and call for alternative discharge strategies or improved treatment performance.
Aside from these scientific outcomes, no additional results (software, protocol, product, …) have been generated during the outgoing phase. Further effort is needed to continue communicating these impacts to regulators and officials to convince them of the severity of these impacts and the benefits of holistic water resource management plans.
Aside from these scientific outcomes, no additional results (software, protocol, product, …) have been generated during the outgoing phase. Further effort is needed to continue communicating these impacts to regulators and officials to convince them of the severity of these impacts and the benefits of holistic water resource management plans.