Nairobi River, Nairobi

The name of the Kenyan capital city comes from the Maasai word for “place of cool waters,” in reference to the city’s namesake creek. Nairobi is located on a gently sloping plain that is high enough not to have malaria-causing mosquitoes, and roughly midway between the seaport city of Mombasa and the vast Lake Victoria on the other side of Kenya. At the turn of the 20th century, British colonial authorities set up a railroad deport at the “place of cool waters,” which in 1905 became the capital of British East Africa.

But as the city has grown, its infrastructure failed to keep up, resulting in massive sewage releases into the Nairobi River, along with chemicals and trash that have choked its flow, killed wildlife and posing a health hazard to people living and working along its course. The crowded scene above is at Pumwani Road, to the east of Nairobi’s Central Business District.

Rio Seco, Luanda

Here’s my first essay on an urban stream in sub-Saharan Africa. In Luanda, the Angolan capital, there’s Rio Seco, or “dry river,” which is barely visible as it flows behind buildings as an open sewer on its way to the ocean.

In the second half of the last century, Angolans first fought a brutal war of independence and then a civil war between the Marxist government and anti-communist guerillas. These days the country is prospering from oil and diamonds. The obelisk on the right marks the tomb of Agostinho Neto, Angola’s first president. Luanda is sprawling, but its urban streams remain neglected.

Mahmoudeya Canal, Alexandria

Having accounted for Oceania in my out-of-town feature, I now turn to Africa and its equivalent of New York: a large and diverse city. The ancient seaport city of Alexandria, Egypt. While many of the cities that I’ve documented were built alongside rivers, Alexandria never had its own river, its location chosen by its famous namesake for its deep harbor that served as a port to Africa.

The city and its harbor were connected to the Nile River and the rest of Egypt by the Mahmoudeya Canal, constructed in the 1840s on the order of the powerful Turkish viceroy Muhammad Ali. Above is a scene on the canal captured in an 1890s French postcard.