Introduction
Between September 15 and October, the Volta River Authority (VRA) conducted a “controlled spillage” of water from the Akosombo and Kpong dams. This is the 11th since the inauguration of Akosombo Dam in 1965. The spillage submerged vast area of land downstream in the Volta, Oti, and Eastern regions of Ghana. Media reports suggest that more than 50,000 people were displaced, while homes, farms, and livelihoods washed away. This created severe environmental damage, economic crisis, disruptions in education and increased hardships for vulnerable individuals. Additionally, experts raised concerns about a potential public health epidemic that could follow the flood disaster. Generally, the situation is described as a humanitarian crisis by many.
While the VRA and the National Disaster Management Organization argue that the spillage was a necessary action to prevent a catastrophic dam rupture, there are critical questions about the management of the process and its consequences on both the ecosystem and society. Notwithstanding, this article primarily focuses on the factors contributing to the variation in water levels in dams such as Akosombo, Kpong, and Weija, leading to spillage disasters in recent years.
Historical Water Level Concerns
The operational water levels for the Akosombo dam ranges between 240.00ft and 278.00ft. Deviations beyond these limits have serious implications for hydroelectric power supply, the environment, life, and property. Historical data, such as research conducted by Eric Ocran in 2015, reveals that the lowest recorded water level occurred in 1966 (234.00ft), while the highest was noted in 2010 (277.54ft).
Although concerns exist regarding both low and high water levels, the prolonged focus had been on the lower values. This concern was substantiated by Eric Ocran’s work in 2015, which indicated a potential fall of levels below 226.00ft, which could cause all the turbines in the dam to shut down. Several researches raised similar concerns about the declining water volume in the dam. Beyond that, the Daily Graphic newspaper reported on a group of pastors who prayed at the dam site to avert a potential prolonged electrical power shortage due to low water levels.
In recent years, however, the situation has reversed and the dams are overflowing. Considering that the VRA attributes this year’s spillage to the water level rise to approximately 276ft, several factors may be accountable for the overflows. Some include lower temperatures/evaporation, increased inflows from tributaries, and developments along river courses. Another might be reduced water consumption in the dam for electricity generation due to the construction of the Bui Dam and the installation of thermal plants.
Climate Change as a Significant Factor
All the factors, notwithstanding, a fundamental question could be whether climate variation is a primary contributory factor. According to the UN’s Intergovernmental Panel on Climate Change (IPCC), Climate Change is long-term shifts in temperatures and weather patterns, caused by the prolonged accumulation of carbon dioxide (CO2) emissions in the atmosphere, and results in more frequent and unpredictable extreme weather events.
The National Aeronautics and Space Administration (NASA), supports this perspective, through data from observations on ground, air, and space, with computer models, that changes in global land and ocean temperatures, rising sea levels, and shifts in extreme weather patterns, such as hurricanes, heatwaves, floods, and precipitation, are associated with climate change.
Local Impact of Climate Change
In a study conducted by Frederick Ebert Stiftung, with the Ghana Agricultural Workers Union, it revealed that Ghana has experienced extreme weather events over the past five years, including severe droughts and heavy rainfall. These events have had devastating effects on agricultural workers and pose significant vulnerabilities to infrastructure, public health, and ecosystems. The World Bank Group’s Ghana Country Climate and Development Report 2022 warns of flooding and drought as consequences of climate change in the country. The report strongly advises the government to establish early warning systems and safety nets for vulnerable communities.
Akosombo Dam Case
Analysing the Akosombo Dam’s situation reveals a notable surge in water levels to about 276ft. This surge is a sharp contrast to the situation in the recent past when the dam was at risk of drying up. Authorities consistently attribute the increased water volume to heavy rainfall, a claim supported by data from the Ghana Meteorological Agency. In addition to heavy rainfall, falling temperatures in the region have significantly reduced water loss from the dam due to reduced evaporation.
Conclusion: The Case for Climate Change Mitigation
The evidence strongly suggests that the overflowing dams in Ghana are indicative of the influence of climate pressures. Urgent measures are required to mitigate the impact on vulnerable communities. There is, therefore, the need to take proactive steps, such as investments in Artificial Intelligent tools for hydroclimatology, runoff modelling, remote sensing, and satellite data for early detection of climate pressures, to determine appropriate responses. Additionally, institutions like the VRA should conduct comprehensive assessments of the estuaries, addressing challenges such as silting in the areas before conducting such massive spillages.
Written by David Kyetong Guun (dkguun@pentvars.edu.gh)