The existing drainage should match with the rate of Kampala population growth and with its expansion and development in all directions
Urban stormwater drainage is one of the services managed by Kampala Capital City, Authority (KCCA).
Kampala is the capital city of Uganda with a population of approximately 1,507,080 people (UBOS 2014). It has a large but poor performing stormwater drainage system.
Kampala stormwater from catchments of Rubaga, Mengo, Makerere, Mulago, Nakasero, Kololo, Naguru, Bahai, Kisasi, Mbuya, Makindye, Mutungo, Muyenga, Buziga, Nsambya, Kibuli, Bugolobi, Luzira and Najanankumbi is drained major channels of Nakivubo, Lubigi, Nalukolongo, Kinawataka, Kansanga and Nyanama-Lufuka.
Kampala stormwater drainage performance is constrained by poor maintenance, insufficient funding, the encroachment of the drainage route, undersize structures, vandalism, blockage by silt and solid waste.
These manmade constraints always cause flash floods during and after intensive rainfall events resulting into loss of lives and property, damage of infrastructure such as roads, bridges and building structures; disruption of traffic; paralysing commercial activities; the outbreak of diseases such as malaria, typhoid; and peoples livelihoods. This has occurred in areas such as Clock Tower, Katwe, Ndeeba, Nateete, Jinja Road near Electoral Commission, Bwaise, Kawempe, Lugogo, Namasuba and Zana.
Community leaders, managers and planners, should note that the existing drainage should match with the rate of Kampala population growth and with its expansion and development in all directions.
To successfully manage Kampala stormwater drainage system, a baseline plan must focus on the following processes.
Planning determines what should be done, who will do it, how much it will cost and how long it will take. The planning should match with plans of urban development, land use and road network. It should, therefore, include the following:
1. Identify the overall objective which is to have high-performance stormwater drainage system with the capacity to convey all the stormwater from the catchments, to control floods, soil erosion and sedimentation.
2. Identify activities of physical engineering using the work breakdown structure method.
3. Prepare a budget cost basing on the required quantities.
4. Make a time schedule indicating the duration of activities.
5. Develop environmental measures to include monitoring the quality of stormwater and flood reduction.
6. Identify socio-economic measures to reduce risks of damage to homes, loss of lives and property, damage of homes, the outbreak of diseases, disruption of livelihood, etc.
7. Involve other institutions or stakeholders such as Ministry of Water and Environment, Ministry of Works and Transport, Ministry of Lands and Housing, NEMA, UNRA, NWSC, Meteorology Authority, Association of Ugandan Engineers and Environmentalists and Universities in the plan. The cooperation efforts guarantee plan ownership by all stakeholders which eliminates conflicting laws and regulations, legal uncertainties and uncoordinated operations.
When the plan is completed, activities can begin. The drainage management head leads a team of engineers, planners, environmentalists, socio-economists, designers to carry out the planned activities within the budget cost and time schedule.
New work or maintenance activities in progress must be monitored to ensure the plan is complied with. This involves periodic measuring the actual quantity and quality of work done against planned activities. Corrective measures can then be done when work is behind schedule.
Completion and evaluation
Every activity must be completed to achieve the planned objectives. This is usually followed by an appraisal which is conducted on the three constraints of work, cost and time against the original plan to establish a level of stormwater drainage performance.
Operation and maintenance
Operation and maintenance follow completion of the drainage system. Drawings, design reports, operation and management manuals and performance records must be available for this purpose.
Stormwater drainage system deteriorates over time due to depreciation of material components. Regular maintenance and repairs shall be done by drainage staff for the system to perform optimally as designed.
After a time, the system requires upgrading to meet current demands and standards.
Records of maintenance, repair and upgrading of the systems should be available to enable sustainable performance and management of the system
Successful drainage management implies the fulfilment of the stated objectives of quantity and quality work within a sufficient budget and time. Performance of the drainage system is realised by proper conveyance of stormwater to the receiving wetlands and Lake Victoria. It is worthwhile to note that these principles can successfully be applied to manage stormwater drainage in other municipalities in Uganda
The writer is a former Special Presidential Assistant