Ethiopian Business Review

The Drainage Master Plan is Delayed Because of Politics.

Jemal Mohammed is the general manager of Blue Matrix Consultancy, and has been working in the field of drainage and sewerage management for the past 20 years. His company has been involved with many projects, like setting up the drainage master plan for Bishoftu (Debre Zeit) town in addition to the preparing sewerage master plans for Dire Dawa, Jimma, Gondar, Adigrat and Hawassa. Blue Matrix is known for designing sanitary landfills for Dila and Bishoftu towns. Four months ago, the company submitted a proposal to participate in the tender floated by the Addis Ababa City Roads Authority for the design of a drainage master plan for the capital. EBR’s Ashenafi Endale sat with Jemal to discuss how to resolve the drainage related problems in Addis Ababa, especially during the rainy season.

 EBR: Does the topography of Addis Ababa expose the city to flooding? 

Jemal: The mountain chain that surrounds Addis Ababa doesn’t prevent rain water from reaching the city anymore due to deforestation. This, together with rapid urbanization, which doesn’t go along with properly designed and constructed road networks, has increased the city’s exposure to rain water overflow. Since natural protection against rain water is diminishing, the impact of storm water nowadays is soaring. That is why we see more storm water on asphalt roads.  The rain water takes a few minutes to reach the center of the capital and causes problems due to the absence of a master plan and proper drainage infrastructure. 

My company has prepared drainage master plans for Sebeta, Burayu and Bishoftu towns, which have been repeatedly hit by rain water runoff because they are located at the foot of the Entoto mountain chain.  The master plan is helping these towns channel rain water before it passes the peripheries and enters the city. The same master plan is needed to address Addis Ababa’s drainage problem. 

In the absence of natural protection what can be done to prevent rain water from reaching the city? 

Interceptor drains, which collect and channel rain water as it flows down to surface should be built. This will prevent the rain water from outside the city from entering Addis Ababa; otherwise it necessitates constructing large drainage canals inside the city.  Due to a lack of resources and limited space, Addis Ababa cannot afford to build such large canals. The good thing for Addis Ababa is there are many river streams. So it is possible to channel the rain water from the interceptor canals directly to the rivers, so it can follow the rivers’ path and exit the city.   

But the Addis Ababa River and Riverside Project Office, which is established two years ago, is working to protect the rivers from any outside interference and keep them clean.

It isn’t rain water that should be kept out of the rivers but sewerage and solid waste. 

In the absence of interceptor canals, does the existing drainage infrastructure inside the capital can accommodate the storm water? 

First, the city doesn’t have an adequate drainage infrastructure. So far, canals are being built without considering the slope of the topography and the expected volume of storm water. The road side canals are only functioning largely as entry points for the storm water. While constructing asphalt roads, most contractors in Addis Ababa install drainage infrastructures that only receive the water rolling in the asphalt roads. In addition, the circumference of the old canals does not fit with the new canals installed in the capital. So, canal sizes should be upgraded and they should be linked into networks. 

Most of the existing canals are filled with household and industrial solid waste as well as sewerage, because there are no separate master plans for drainage, sewerage and solid waste management.  It is just luck and the existing rivers that have prevented floods from causing major disasters in Addis.

The Addis Ababa City Road Authority (AACRA) has canceled the tender it floated for preparation of drainage master plan repeatedly. Considering this, do you think it is too late to solve the drainage related problems with the upcoming master plan?  

The drainage master plan has been delayed because of politics rather than technical and capacity related issues. There is still a lack of commitment and willingness from the government, evidenced by the successive cancelation of tenders floated for the preparation of drainage master plan in the past for no reason.  Even if AACRA decides to go ahead with the tender it floated four months ago, selecting a winner will take time. 

This is despite the fact that problems have been accumulating for years. It is very difficult to address drainage related problem in a city like Addis Ababa, which is exposed to intense rainfall and experiencing rapid urbanization without a master plan. It would have been better if the master plan was introduced before the construction of the Light Railway Transit network. But preparing a drainage master plan is a now or never task before the problem worsens.

What are the factors that should be considered while preparing the master plan?

To design a drainage master plan, charting the locations, slopes and directions of existing canals is the first task. Incorporating these into the desired master plan, considering any changes in the future will be next job.  To do this, there needs to be crosschecking of overlaps and inadequacy, and realignment, upgrading and redesigning should be done. The ideal master plan should ensure the functionality of the existing drainage infrastructure on top of allowing the construction of new ones with low cost and little demolition. 

Do you think establishing an independent institution is necessary to handle the problem better?   

The issue is not only about constructing drainage infrastructure but also management. So for Addis Ababa, It is better if the responsibility stays at AACRA, but the department should be well organized and equipped with the necessary capacity.


6th Year . July 16 - Aug 15 2018 . No.64


 

 

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