CONTEXT:
The Isimba dam is located on Uganda’s White Nile, some 50 km downstream from the river’s source, Lake Victoria. Operational since 2019, Isimba is designed to meet the country’s present and future energy needs. Isimba is the second of several dams built in recent years after the Bujagali dam, located 40km upstream. Once the other dams are built, Uganda will have energy supply far in excess of its demand.
PROJECT IMPACTS:
Isimba’s reservoir impacted the Kalagala Offset Area, is home to a site of significant cultural, spiritual, and biodiversity value for local communities. By impacting the Kalagala Offset, the reservoir has also submerged five rapids, which has significantly impacted the whitewater rafting industry, one of few large employers in an underserved part of the country.
IMPACTS ON FRESHWATER SPECIES
The Isimba dam was constructed along a biodiversity-rich stretch of the White Nile River, which is home to many endemic fish and other species. Some of these fish species were particularly prevalent around the Kalagala Falls and the Isimba site, which is common since river rapids are often host to a great diversity of fish species. Isimba’s impacts on these species is of particular concern to fishermen, who comprise roughly 15% of the local population.
Biodiversity Snapshot
IUCN red list species & status:
CRITICALLY ENDANGERED
Victoria tilapia
Ningu carp
Haplochromis brownae
(possibly extinct)
Home to 88 different bird species and 20 haplochromine cichlids
(at least one critically endangered)
VULNERABLE
Leopard
Hippopotamus
PROJECT IMPACTS
LESSONS
ISIMBA
Uganda
Dam submerged a portion of a biodiversity offset on Uganda’s White Nile
Image by Chris Stenger
Vulnerable hippopotamus
Image by International Rivers
Murchison Falls
Image by International Rivers
Isimba construction site
Biodiversity Snapshot
IUCN red list species & status:
CRITICALLY ENDANGERED
Victoria tilapia
Ningu carp
Haplochromis brownae
(possibly extinct)
Home to 88 different bird species and 20 haplochromine cichlids
(at least one critically endangered)
VULNERABLE
Leopard
Hippopotamus
Company: China Three Gorges
Subsidiary: China International Water & Electric
Impact Category
Biodiversity Hotspot
Impact Category
Protected Area
CAPACITY
183 MW
COST
$566 million
STATUS
Operational
Local Community Impact
The dam has harmed the local rafting tourism economy and many of the 2000 people displaced by the dam were not compensated until years after displacement.
1.
The Isimba dam’s impacts on a biodiversity offset should have excluded the project from CWE’s consideration.
2.
In future projects, CWE should ensure that all environmental and social impact assessments, including biodiversity impacts, are conducted prior to construction and in line with international standards, and disclosed to the public.