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.