Green Hills, Blue Cities

Ayenew, T. and Belliethathan, S. URBANISATIONANDWATER POLLUTIONINADDISABABA

Addis Ababa, the capital of Ethiopia and one of the largest cities of Africa, is located at the edge of the East Africa Rift Valley. Since its establishment 130 years ago, the city has grown from a sparse and scattered settlement to 530 km 2 (Alemayehu 2005).

Samuel. With the exception of Aba Samuel, all reservoirs supply domestic and industrial water. The Aba Samuel Reservoir was constructed in the late 1930s for electricity generation, and today some of the municipal and industrial effluents are discharged into this reservoir (EPA 2005). The city is also dependent on groundwater, supplied through springs, and shallow and deep wells. Most of the springs are found at the foot of the northern Intoto mountain range. The Akaki well located close to Aba Samuel Dam is a major water supplier for the city. During its first fifty years, Addis Ababa was supplied by the Intoto springs. Due to increasing water demand a water treatment plant was built in 1938 at the foot of Intoto Ridge, and in 1944 the Gefersa Dam was built (Semie 1998). In 1970, the Legedadi Dam and treatment plant were commissioned. This was followed by the development of groundwater sources, as well as the construction of the Dire Dam. The demand for potable water was estimated at 204 000 m 3 /d in 1994, and this was projected to increase to 431 000 m 3 /d and 1.1 million m 3 /d in 2006 and 2020, respectively (Semie 1998). Currently the demand for water in the city exceeds supply. And the current water supply coverage is 70 per cent (AAWSA 2011 personal communication). Addis Ababa’s sanitation coverage is low, with 13 per cent of the city’s population using flash toilets, 57 per cent using pit latrines and 30 per cent having no sanitation facilities at all (AAEPA 1999).

ERITREA

YEMEN

Áksum

Mek’elé

Maych’ew Weldiya

Gonder

DJIBOUTI

SUDAN

Desé

Debre Mark’os

Debra Birhan

Diré Dawa

Asosa

Addis Ababa

Nek’emté

Jijiga

Metu

Degeh Bur

Gambéla

Jima

K’ebrí Dehar

Awasa Goba

Imí

Árba Minch’

Kibre Mengist

Godé

Negélé

SOMALIA

KENYA

UGANDA

In the last 50 years, the population of Addis Ababa has grown from 100 000 to 2.7 million in 2007 (Central Statistics Authority 2007), and to 3.5 million inhabitants in 2010 (UN- HABITAT 2010). Due to the growing population, the city is facing challenges in providing its residents with enough freshwater and sanitation services.

WATER SUPPLY AND SANITATION

AddisAbaba is locatedwithin theAkaki River Basin, which covers an area of 11 454 km 2 (Ebba 2006). There are four artificial water reservoirs in the basin, namely Legedadi, Gefersa, Dire and Aba

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