Dandora ponds (6425)
Kenya, Africa

Site overview

KBA status: confirmed

Global KBA criteria: D1a

Year of last assessment: 2001

National site name: Dandora ponds

Central coordinates: Latitude: -1.2333, Longitude: 37.0167

System: freshwater, terrestrial

Elevation (m): 1500 to 1500

Area of KBA (km²): 3.47082

KBA classification: Global

Legacy site: Yes

Site details

Site description: The Dandora Oxygenation Ponds are situated 20 km due east of Nairobi City centre, just off the Nairobi–Kangundo road but within the city limits. The main sewage treatment works for Nairobi City, they comprise three experimental ponds, eight facultation ponds and 24 maturation ponds, all bounded by embankments. The first phase of eight ponds was commissioned in 1980, followed by the much larger second phase in 1992. The older set has mud banks, with associated growth of aquatic and emergent macrophytes such as species of Cyperus and Typha; the newer ponds have gently sloping concrete banks. Water quality and the microflora and fauna change as water progresses through the ponds. The treatment is entirely natural and considered environmentally friendly. Processed water from the ponds is discharged into the Nairobi river.

Rationale for qualifying as KBA: This site qualifies as a Key Biodiversity Area of international significance that meets the thresholds for at least one criterion described in the Global Standard for the Identification of KBAs.

Additional biodiversity: See Box for key species. Dandora holds internationally important populations of Netta erythrophthalma (maximum 3,200 in 1994) and (in the northern winter, November–February) Anas clypeata. Duck are generally numerous, and there are often large flocks of Dendrocygna viduata and D. bicolor, Anas undulata, A. erythrorhyncha, A. hottentota and (among the Palearctic migrants) A. acuta and A. querquedula. January waterbird counts over the eight years 1994–2001 have recorded up to 65 species and a maximum of 22,450 waterbirds (mean, 11,900), duck usually being the most abundant single group. Over 1,000 Chlidonias leucopterus are frequently present. Other conspicuous waterbirds include ibises, herons, geese and a variety of migrant shorebirds. Migrant Motacilla flava and Anthus cervinus are attracted to the pond edges, and seasonal flocks of bishops and queleas occur in the rank vegetation surrounding the complex. The regionally threatened Casmerodius albus is a sporadic visitor, in small numbers. Non-bird biodiversity: None known to BirdLife International.

Habitats

IUCN Habitat	Coverage %	Habitat detail
Wetlands(Inland)	100

Threats

Summary of threats to biodiversity at KBA: The ponds support not just birds but other aquatic animals such as Hippopotamus amphibius, Crocodylus niloticus, and unknown species of fish. Mass die-offs of waterbirds have occurred at least twice at Dandora, apparently from bacterial toxins produced under unusual weather conditions, but these have been short-lived phenomena. The ponds have considerable potential for environmental education, especially for school children. However, although they are close to Nairobi and easily reached by public transport, access requires special permission and is generally discouraged. Management as a sewage treatment works, which is obviously the primary objective, is not necessarily incompatible with bird conservation or education, but the value of the site for wildlife is not yet fully recognized by the City Council.

Threat level 1	Threat level 2	Threat level 3	Timing
Agriculture & aquaculture	Annual & perennial non-timber crops	Small-holder farming	Ongoing
Pollution	Domestic & urban waste water	Sewage	Ongoing
Residential & commercial development	Housing & urban areas		Ongoing
Transportation & service corridors	Flight paths		Ongoing
Transportation & service corridors	Roads & railroads		Ongoing

Additional information