Industrial discharges, runoff from urban centers and lack of proper solid waste disposal in Ethiopia are impacting the rivers and lakes with serious public health and environmental implications. Recent media reports on Lake Koka provide a glimpse of the severe health consequences of water pollution on populations drawing water from that lake. Beyond the immediate health impact, lack of proper environmental management of water resources adversely affects tourism and the economic development of the country in general.
Remediating the effects of long-term industrial discharge, urban runoff and improper disposal of solid waste can be very expensive particularly for poor countries. For instance, the development cost for a small surface water treatment system in sub-Saharan countries requires the equivalent of 10 years’ salary per household. These countries are not only under resourced financially to implement large scale environmental remediation, they also lack the experience, administrative infrastructure, and technology to operate and maintain the systems.
It is necessary to find simple but effective, energy-efficient and inexpensive large-scale surface water treatment systems for major regional urban centers. There are such systems currently available that could be used to remediate Lake Koka and other water resources in Ethiopia. Over the past several years, we have been working with a surface water treatment technology that has evolved in its performance, energy efficiency and durability in hostile climates. One such technology that is suitable to Lake Koka is the solar powered circulation equipment. This technology utilizes patented near laminar flow (streamline flow) technology, to provide high-flow long-distance circulation that can improve water quality in almost any size surface water body such as freshwater lakes and reservoirs, drinking water tanks and wastewater recycling ponds and lagoons. This treatment technology will be ideal to treat the contamination in Lake Koka.
This surface water technology has many attractive features. It operates on solar power and is serviceable 24 hours a day. Its water intake design could be adjusted for depths ranging from 1 to 100+ ft. It is also simple to install and requires minimum maintenance. It is encased in a stainless steel and corrosion-resistant polymer construction with an expected 25-year service life.
The benefits of this technology are numerous. In the Lake Koka context, for instance, the technology could help control and eliminate harmful blue-green algae blooms, reduce aquatic weed growth, eliminate taste and odor problems in drinking water, improve fish habitat, enhance dissolved oxygen and pH levels and promote the breakdown of organic chemicals in surface water.
If such technology were used in Lake Koka, a number of preparatory things would have to be done. Prior to installation and treatment, it will be necessary to collect basic data on the health of the lake. Among the first tasks would be data collection on such things as contaminant sources points, PH, temperature, conductivity, approximate width, length and depth of the lake, and water level data. The cost associated with the installation of this system in Lake Koka would be in the range of $50,000 – $75,000. With only once a year maintenance cost of approximately $1,000/year for 3 years, the system is guaranteed to provide worry-free service for decades, and can be used in multiple surface water bodies.
It is possible to begin full reclamation of Lake Koka. It will require the cooperation of governmental agencies in Ethiopia and support by all parties interested in bringing that lake to its previous state of viability. We believe there are Ethiopian and other experts who would like to help in a future Lake Koka remediation project by donating their technical services. Many others are likely to be supportive of such a project financially if a well organized effort could lead it.
The idea for remedial intervention for Lake Koka proposed here is supported by twenty three years of environmental studies, of which the last nineteen years have focused on environmental impact assessments, hydrogeologic studies, water supply, environmental remedial investigations and remediation projects in Africa, South America and the United States. I have had in-the-field experience working with local governments and NGOs in Africa and Latin America on numerous water supply and water quality projects. Within the past seven years, I have traveled four times to Africa and performed several surface and groundwater studies.
—- Aklile Gessesse is a P.G. Licensed hydrogeologist. He is currently an Environmental Project Manager for AECOM, Alexandria, VA, and is responsible for various remediation projects. He was previously employed by the Bechtel Corporation in similar capacity. He may be reached at [email protected]
