Works at Lubigi will include leveling within the channel and lining. KCCA plans to use concrete cable lining where concrete blocks are joined together using cables. This Baagala says is a flexible technology that eases excavation works during maintanance. Linning reduces the streams roughness, which in effect quickens the flow of water through the stream channel.
Part of the unlined Lubigi Drainage Channel in Bwaise
Kampala Capital City Authority - KCCA is set to start expansion works on Lubigi and Nakamiro drainage channels.
The project is implemented under the World Bank funded Kampala Infrastructure Institution Development Project -KIIDP II and government of Uganda.
World bank provided USD 183.7 Million to KCCA to conduct studies, carry out engineering works, construction of drainage, roads, and capacity building. Planned works at Lubigi and Nakamiro channels are estimated to cost 80 billion shillings.
According to the Communications Specialist KIIDP II Agnes Biribonwa, the project will start next month November and is expected to last 18 months until April 2021.
KCCA was supposed to start works in 2017 but compensations around the Nakamiro channel among other issues stalled the project. KCCA Head of Drainage Engineer Brian Baagala told URN in an interview that KCCA has now achieved the atleast 65% compensation payments that is required by World Bank to approve and release funds for works to begin.
A total of 2.5km of the 7km Lubigi drainage channel will be expanded and lined with concrete from Bwaise to Kawaala. Baagala says the works will take place within the existing width which is about 100meter.
KCCA plans to use concrete cable lining where concrete blocks are joined together using cables. This Baagala says is a flexible technology that eases excavation works during maintainance. Lining reduces the streams roughness, which in effect quickens the flow of water through the stream channel.
Lubigi is a primary channel fed by about eleven secondary channels including Nakamiro, Katanga, Nsoba, Kiyanja and others. Of these, Nakamiro is the longest with about 11km and is the most populated. It has about eight tertiary channels that feed it direct from the communities.
Baagala says each of the tertiary channels has a width of 2 meters meaning that 2 meters times eight channels is 16 meters feeding into Nakamiro channel which is 16 meters. Yet, Baagala says there are more water channels although not yet properly constructed as tertiary channels that feed into Nakamiro channel.
As a mitigation measure to the above challenge, KCCA will also expand Nakamiro channel. A total of 3.2 km will be expanded and lined with concrete from Kazo Angola to Lubigi. The channel will have an average width of 7m and there will be provisions for pedestrians to cross the channel safely. About 332 properties are affected at Nakamiro and compensation is on going, says Baagala.
Baagala says that after works, KCCA will embark on engaging the communities on proper handling of waste to avoid having a lot of waste ending up in the channels and sometimes causing blockage which could lead to flooding.
Kampala is faced with a challenge of flooding and KCCA is pushing for a proper drainage system through its drainage Master Plan. The plan involves construction of Drainage channels, reducing storm water and establishing water retention ponds.
KCCA has been implementing the drainage channel system not only to curb flooding but also provide safety for vulnerable communities living in wetlands. The constructed community drains ensure that deep drainage holes are secured, and damping of solid waste is deterred.
Kampala has eight primary channels including Lubigi, Nakivubo, Mayanja, Nalubaga, Kinawataka, Kansanga and Ggaba drainage channel.