I remember back in the late 80s, Lake Haromaya had been one of the splendours of Haromaya town. The fresh breeze you inhale in the vicinity located off the main road to the city of Harar was a food for the soul. The fauna and flora you could see just standing near the marsh shore of the lake that was covered with tall savannah grasses used to give inner peace and tranquillity to the mind. Though the lake was quite small nearly covering five square kilometres and a depth of about eight meters, it was immensely important for the conservation of nature and biodiversity in the region, in addition to its glamour. Today, it is a dry land with no trace of its existence.
I also do remember that there were repeated concerns and warnings from local research groups about the dangers facing the lake during those days. As Harar, in the bigger picture, was in a chronic shortage of water for many years in those days, there was excessive use of water from the lake for irrigation and drinking purposes.
In actual fact, Ethiopia has painful experience regarding the total loss of Lake Haromaya and other less popular ponds/lakes, streams and wetlands. The “death” of Lake Haromaya was as a result of unbalanced misuse of the freshwater as stated above. The freshwater was overused mainly for drinking and irrigation but also for fishing, recreation, washing, etc.
The local community had even suffered from a shortage of freshwater subsequent to the collapse of the lake. Attempts to resurrect Lake Haromaya have recently been reported to fail.
Enclosed within the Abiajata-Shala Park, the other endangered lakes of the country are Lakes Shala and Abijata. Warnings have been heard from local scholars about their endangered scenario due to population pressure and consequent human factors like deforestation. There are large numbers of households living in the Park who have a large number of domestic animals. Deforestation in the park is pervasive. Today, the water level of Lake Abijata has significantly diminished and has withered. The fishery has totally disappeared, and birds such as Lesser Flamingo and Pelican have reported having migrated to other places. The environmental conditions in the Park are worsening and the lake is shrinking eventually facing imminent collapse with all its services and benefits unless appropriate measures are immediately taken. Making the long story short, Lake Abijata and Lake Shala is already “dying” under the eyes of concerned people and decision makers.
The other one and perhaps the main focus of this short article is the precarious situation facing Lake Tana in the last decade. Unlike other endangered lakes of the rift valley region, Tana is not mainly challenged by human factors. There has been a strange infestation of the lake by a dangerous weed called Water hyacinth. Studies indicate that the weed is an exotic free-floating invasive plant that is native to South America. People who keep aquariums and gardens are believed to have spread the plant inadvertently across the Atlantic to Africa and Asia.
The weed restricts water flow, blocks sunlight from reaching native water plants and depletes the oxygen in the water – often choking aquatic animals like fish. It also has an economic impact by interfering with navigation, irrigation, power generation and fishery. Before trying to see the possible ways of mitigating the problem as proposed by researchers, it would be vital to overview of the economic and natural conservation benefits of the lake to Ethiopia and the East African region.
To begin with, Tana is said to hold fifty percent of the country’s fresh water. It is also the source of the Blue Nile, which contributes up to 60% of the Nile’s water. Not only is the lake important as a water source for over 123 million people in the Nile Basin, it is also a source of food in the form of fish. The lake has been listed in the top 250 lake regions of Global Importance for Biodiversity. Studies show that Tana is blessed with 28 species of fish, of which 21 are endemic. Commercially, the Lake’s most important fishes include the large African barbs, Nile tilapia and African catfish. The annual commercial value of fish production at Lake Tana is about USD 1.1 million, as some reports indicate. The potential fish production of the lake is estimated to be 13 000 tons yearly. But its current fish production is less than 1000 tons a year, even reported to be far lesser in 2018/19.
In addition to its ecological and economic values, Tana is a very important tourist destination which dictates Ancient Ethiopia to modern times. Blessed with amazing historical and traditional virtues of the traditional schools of the country, and at the same time holding thirteen very old monasteries at the heart of the great lake, it is one of the most important holy sites to millions of followers of the Ethiopian Orthodox Christianity.
It was in 2011 that the regional Environmental Bureau named water hyacinth as the most dangerous weed affecting Lake Tana. By then, about 20,000 hectares of the north-eastern shore of the lake was reported to have been infested. In the subsequent three or four years, local researchers disclosed that about one-third of the Lake’s shoreline, around 128km, was invaded by water hyacinth. Only God knows how much of the Lake is coved with the weed today; taking into account its amazing propagation to cover a huge mass of the lake within days.
To make matters worse, according to some studies, inflowing rivers carry heavy loads of soil and suspended sediment into the lake, which affects the water quality and creates favorable conditions for the spread of the weed.
A water hyacinth infestation is hard to get rid of. But there are three ways to do this as proposed by experts. These are removal, chemical spraying (using herbicides) and biological control. Removing the weed, either manually or using machines, could reduce coverage and slow its spread. But it’s expensive and takes time.
Some mention experiences in Lake Victoria, lying in Tanzania, Uganda and Kenya, as a lesson for dealing with the water hyacinth problem. Literature indicates that an estimated 60,000 hectares are covered by the weed in Kenya alone. A weed harvesting machine can clear only 10 hectares a day, so it would take 6 000 days (more than 16 years) to remove the weed entirely. Methods like biological control have been shown to be more effective. Herbicides have been widely used to reduce the spread of the weed, but they may harm the environment. They can kill native plants that are necessary for the healthy functioning of the lake’s ecosystem. This control method is expensive for developing countries and requires highly skilled people. In Sudan, the costs of chemical treatment for water hyacinth control were estimated to be One million Euro every year.
With all these premises in mind, it is not difficult to comprehend the precarious problem the country is facing regarding Lake Tana. The mitigation endeavour is also exorbitant. And it might not be that difficult to comprehend that the rescue business might have become beyond the capacity of the regional government. Yet, it can never be beyond the capacity of the people of this great nation. Despite the current impediments challenging us today like the covid19 and the subsequent economic downturn, we can arrest the weed through determination and perseverance. The great leadership and the acumen of our Excellency Prime Minister Dr.Abiy Ahmed to mobilizing the whole people towards saving Lake Tana, if not limited to it, we can do it. First and foremost, however, the regional government must show the same commitment. Many show resentment regarding the effort of the regional state to mitigate the problem so far. Be it as it may, Lake Tana is a huge resource; which is too big to be a concern of just a regional government. To sum up, the lake is in a precarious situation to the extent that the rescue effort cannot be scheduled for months. It is now or never!
The Ethiopian Herald May 28, 2020
BY ENDALE ASSEFA
