TC Vietnam: Climate resilient management of groundwater and geohazards
Report of the project:
Background
The Mekong Delta, a flat low-lying coastal area of about 40 000 km2, provides livelihoods for more than 17 million people and is one of the world's regions most affected by climate change. Groundwater represents an essential component for securing domestic and industrial supplies and is the main backup water source during droughts for the people living in the Mekong delta, especially in the coastal zones. Its importance grows against the backdrop of climate change, upstream encroachment, and development in the Delta. The Mekong Delta faces a complex set of problems that significantly threatens its existence as a living and economic space in its current form.
Due to its flat topography, the delta is not only sensitive to slow climate change, land subsidence and sea level rise, but also highly exposed to extreme flood events. Unsustainable land use practices contribute to an imbalance of water and sediment fluxes. Reduction of water flow (e.g. presence of dams) and deepening of river beds (e.g. sand mining) favours the penetration of seawater far inland, leading to salinisation of water bodies and soils and increasing the demand for groundwater.
At the same time, these coastal regions are exposed to diverse geohazards that are exacerbated by improper management of land and water resources. These include areal land subsidence processes favoured, for example, by groundwater withdrawals and reduced sedimentation, but also erosion along river courses, channels, and coasts, for example, because of sand extraction.
Intensive management of the Mekong Delta not only increases the overall water demand, but also makes the economic area increasingly vulnerable to dry periods. The consequences of inappropriate management of land and water, as well as climate change, challenge the existence of this ecosystem, its role as an essential supplier of rice and other agricultural products, and the livelihoods of its people.
Map of the Mekong Delta and the provinces covered by the project
Source: BGR
In partnership with the National Centre for Water Resources Planning and Investigation (NAWAPI), BGR has been collaborating under the “Improvement for groundwater protection in Vietnam (IGPVN)” project since 2009. The follow-up project "Climate resilient management of groundwater and geohazards" (CRMGG) focuses on five provinces of the Mekong Delta:
- Sóc Trăng (focus of investigation in project IGPVN II from 2012–2014);
- Cà Mau (mainly in project IGPVN III since 2015);
- Bạc Liêu (in project IGPVN IV since the end of 2020);
- Hậu Giang (in project CRMGG since the end of 2022);
- Kiên Giang (in project CRMGG since the end of 2022).
The project supports the national and provincial partners in four components.
1. Capacity development at national and provincial levels
Safeguarding of previous project results
An action plan for the consolidation and replication of best practices in groundwater management from the previous IGPVN project was drawn up together with the five provinces (Sóc Trăng, Cà Mau, Bạc Liêu, Hậu Giang and Kiên Giang). The action plan aims to improve the transfer and integration of pre-2022 products findings to the provincial authorities (DONREs) and enable replication of best practices to the two newly selected provinces (Hậu Giang and Kiên Giang). The action plan focuses on four core topics: groundwater monitoring network, digital groundwater information system, well survey, and evidence-based decision-making.
Training on operation and maintenance of telemetric monitoring equipment and data processing
Source: BGR
Training and support measures for the provincial environmental authorities (DONREs) in the areas of digital groundwater management, well cadastre and monitoring have been initiated based on the experiences and concepts of the previous project. This included a training on the Groundwater Information System Database (GISD) for Bạc Liêu province in July 2022 and Hậu Giang province in January 2024, a training on well inspection for Bạc Liêu province in September 2022 and Hậu Giang province in August 2023, as well as a training on the operation and maintenance of groundwater monitoring wells for four provinces in November 2022.
Improved capacity to manage groundwater and geohazards
Experts from the national partner have been sent for training in “Managed Aquifer Recharge (MAR)” at the HTW Dresden (September 2022 and July 2023), “Groundwater Modelling and Climate Change” at Deltares Singapore (February 2023) and to the European Geosciences Union (EGU) General Assembly in Vienna (April 2024).
2. Practical solutions for groundwater and geohazards management
Managed aquifer recharge
While there is usually sufficient fresh surface water during the wet season, surface water resources are often becoming too saline to use during the dry season. To bridge this gap, managed aquifer recharge (MAR) is a promising technology, which is to be tested as a solution for the Mekong Delta in the form of feasibility studies and pilots. Two activities are currently being implemented:
Schematic for aquifer storage and recovery (ASR) using one well for both recharge and recovery (left), and aquifer storage, transport and recovery (ASTR) using one well for recharge and another well for recovery (right)
Source: Dillon (2005), DOI: 10.1007/s10040-004-0413-6
- Support to a Ministry of Natural Resources and Environment (MONRE)-funded pilot study undertaken by the national partner NAWAPI in Hậu Giang Province together with the local water supply company (HAWASUCO). The first two rounds of infiltration tests for aquifer storage and recovery (ASR) on two wells of different depths were completed at the end of 2023. A further rounds of tests has begun and new Internet of Things (IoT) instruments are being tested simultanously;
- Support to an ASR pilot implemented by Deltares, VEI and the local water supply company in Hậu Giang (HAWASUCO). In cooperation with NAWAPI, the CRMGG project will support the construction of a new injection well, monitoring of groundwater quality and dissemination of results. A monitoring borehole was already installed in January 2024.
Geohazards
Among the existing geohazards in the region, the project focuses on land subsidence. The project intends to support the partners in the monitoring aspect, in cooperation with the German-Vietnamese research project ViWaT, led by Karlsruhe Institute of Technology (KIT). The individual monitoring measures to be implemented will be defined in the second half of 2024.
3. Digital transformation
The project assists with the implementation of NAWAPI's digital transformation strategy (146/QD-TNNQG) in three thematic areas:
Training on Python programming language
Source: BGR
- Development of the big data architecture and cross-site infrastructure to improve central data storage, data organisation and data exchange;
- Development of digital platforms for data provision and visualisation to foster cross-institutional networking;
- Further development of the system for automated operation (e.g. IoT), monitoring and forecasting of water resources.
After a status and need assessment at NAWAPI and its three regional divisions in 2022, the expansion of the cross-site data architecture started in March 2023 with training for IT specialists and engineers from all 4 NAWAPI sites.
4. Awareness-raising and scientific advice
Raising awareness among relevant actors and improving scientific policy advice applies to topics covered by the three other components, for example:
The CRMGG project team at VACI 2023
Source: BGR
- Potential and limits of artificial groundwater recharge or storage for climate resilience (literature review of existing projects carried out in 2022);
- Assessment of the state of knowledge on land subsidence processes in the Mekong Delta;
- Groundwater issues faced by the Mekong Delta and climate change adaptation.
This component takes various formats such as exchange of experience during expert panels, thematic white papers for evidence-based support of dialogue and decision-making process, public information events with political decision-makers at both national and regional levels (e.g. at the Vietnam Water Cooperation Initiative –VACI 2023 & 2024–) and workshops.
Partner: National Center for Water Resources Planning and Investigation (NAWAPI)
Project website: "Improvement of Groundwater Protection in Vietnam (IGVPN)"
Literature:
Techincal reports
- DE JONGE, M., STEINEL, A. & JANSEN, S. (2024): Water quality assessment and recommended monitoring for ASR pilot location Nga Bay. Report No 3. Partners for Water project: ASR application for Domestic Fresh Water Supply in the Vietnamese Mekong Delta. Unpublished report.
- STEINEL, A., DE JONGE, M. & JANSEN, S. (2023): Concept for initiall water quality assessment and water monitoring plan during implemntation fro ASR pilot in Hau Giang province. Report No 1. Partners for Water project: ASR application for Domestic Fresh Water Supply in the Vietnamese Mekong Delta. Unpublished report.
Presentations
- OSENBRÜCK, K., BÄUMLE, R., STEINEL, A. & MANH, L.V. (2023): Age and Hydrochemical Evolution of Deep Groundwater in the Mekong Delta, Vietnam - International Symposium on Isotope Hydrology, 3-7.7.2023, Vienna, Austria. (PDF, 2 MB)
- OSENBRÜCK, K., STEINEL, A., MONTCOUDIOL, N. & BÄUMLE, R. (2024): 14C-Grundwasseralter als Indikator für anthropogene Veränderungen der Grundwasserströmung im Mekong Delta, Vietnam - Vortrag bei der 29. Tagung der Fachsektion Hydrogeologie e.V. in der DGGV e.V., 20-23.3.2024 in Aachen, Deutschland. (PDF, 1 MB)
- RENCK, A. (2023): Climate resilience for the Mekong Delta: the role of groundwater. - Presentation of the CRMGG project at the Vietnam Water Cooperation Initiative (VACI 2023) on 2.3.2023 in Hanoi. (PDF, 2 MB)
- STEINEL, A. (2024): MAR pilots in confined aquifers as climate-resilient solution for the Mekong Delta. - Presentation at the Vietnam Water Cooperation Initiative (VACI 2024) on 15.3.2023 in Hanoi, Vietnam. (PDF, 3 MB)
Posters
- BGR & NAWAPI (2023): Deep-well aquifer storage and recovery - Solution for seasonal water supply shortage Hau Giang pilot site (PDF, 553 KB)
- BGR & NAWAPI (2023): Climate resilience for the Mekong Delta: the role of groundwater. Why is groundwater important? (PDF, 887 KB)
- BGR & NAWAPI (2023): Climate resilience for the Mekong Delta: the role of groundwater. What are the impacts of groundwater use? (PDF, 2 MB)
- BGR & NAWAPI (2023): Climate resilience for the Mekong Delta: the role of groundwater. What does the future look like? (PDF, 860 KB)
- BGR & NAWAPI (2023): Climate resilience for the Mekong Delta: the role of groundwater. What are the management challenges? (PDF, 1 MB)
- OSENBRÜCK, K., BÄUMLE, R., & STEINEL, A. (2023): A Novel Approach to Estimate Radiocarbon Ages of Deep Groundwater at the Mekong Delta, Vietnam. - Poster presented at the 1st Scientific Symposium "Dating Methods in Environmental Sciences" of the Core Facility Environmental Analytics on 15-16.6.2023 in Dresden, Germany. (PDF, 630 KB)