Choking from Hyacinth: Nature-Based Solutions to restore lake Tana.
Lake Tana, Ethiopia’s largest freshwater lake and the source of the Blue Nile, is under significant environmental stress. The water hyacinth has become a significant ecological and environmental problem in Lake Tana, Ethiopia’s largest freshwater lake. Speaking during a Nile basin webinar for Science journalists , Yohannes Zerihun a Senior Ecohydrologist and Practicing Water Resources Engineer, says Ethiopia has introduced eco-hydrology,a holistic, nature-based solution that integrates hydrology and biota to rehabilitate and protect ecosystems sustainably to restore Lake Tana.
He added that Unsustainable human activities such as improper agriculture, urbanization, and pollution have degraded its water quality, disrupted its nutrient cycle, and threatened biodiversity. Traditional water resource management, based solely on mechanical approaches, has proven insufficient in addressing these challenges.
The Role of Ecohydrology
According to Zerihun, Ecohydrology is an interdisciplinary science that emphasizes the interaction between water and living organisms. Historically, hydrologists have focused on water systems, while ecologists have studied biological systems separately. However, these two aspects are inherently linked, making it essential to manage them together.
The system utilizes natural ecosystem properties to restore, rehabilitate, and enhance environmental sustainability at a river basin scale. It incorporates four key elements: water, biodiversity, ecosystem services, and resilience, all of which contribute to achieving Sustainable Development Goals (SDGs), particularly SDG 6 (clean water and sanitation) and other water-related targets.
Implementing Ecohydrology at Lake Tana
According to Zerihun ,Ethiopia adopted ecohydrology principles from the European Regional Center for Ecohydrology in Poland and initiated a pilot project at Lake Tana. This initiative aims to protect the lake’s ecosystem, benefiting both Ethiopia and downstream nations that rely on the Blue Nile.
One of the major challenges faced by Lake Tana is shoreline degradation, particularly due to recession farming and encroachment on the lake’s ecosystem, leading to the proliferation of invasive species such as water hyacinth.
Conventional mechanical removal of water hyacinth has not provided a long-term solution, necessitating a more sustainable approach.
Nature-Based Solutions: Shoreline
To address these environmental threats, an integrated ecohydrology and circular agriculture approach was implemented along the shoreline of Lake Tana. The objectives were twofold:
Rehabilitation of Shoreline Vegetation – Restoration of Papyrus-dominated ecosystems, which play a critical role in stabilizing the water cycle, filtering pollutants, and enhancing biodiversity.
Enhancement of Livelihoods – Introducing sustainable agriculture practices that replace recession farming with circular agriculture, thereby reducing pollution while providing economic benefits to local communities.
This initiative highlights the power of integrating ecological principles with hydrological science to ensure long-term environmental resilience
