Just over a week ago, M. Sanjayan, the lead scientist for the Nature Conservancy, posted photos of a “suds tsunami” rising from a polluted river in Nairobi and spilling over a highway. He’s added this video snippet, in which you can here him say, “No river should be doing that. Mountains of foam, in Nairobi.”

He added this text note:

Not far from the Kenya Wildlife Service headquarters, the road I was on was blocked by a wall of suds, white and fluffy as if spewing out of an errant giant steam carpet cleaner. It was well over two stories high in places.

He’s written more on the incident and related issues on the HuffPost Green blog.

Interestingly, there he linked to a Web Ecoist post, “Water Colors: 10 Unnaturally Dyed Polluted Rivers,” which brought me full circle back to a special report I wrote in 1996 about the polluted history and remarkable (if still incomplete) cleanup of the Hudson River.

Here’s a passage from my article — focused on the Hudson around Beacon, N.Y. — that I think offers a helpful reminder that Nairobi’s (and Shanghai’s and Lagos’s and Delhi’s) pollution problems now were echoed here just two generations ago:

[Shabazz] Jackson, Beacon’s environmental director, recalled how in the 1950’s he and other students riding a crosstown school bus would often pool lunch money before reaching the Fishkill Creek — a Hudson tributary — and make bets on the color of the water. A fabric-dyeing plant upstream kept them guessing. Pollution shaped other childhood rites, as well, including summertime swims. To avoid dunking heads in tainted water, Mr. Jackson said, “kids in Beacon never learned to dive.” Other Hudson Valley residents recalled the dense pillows of white foam that would slowly drift by on the river — effluent from factories. Children would compete to see who could get a tossed stone to perch on the fluff.

Let’s hope that countries going through their industrial, and polluting, growth spurt now can undergo the same transition, so that there, too, foaming rivers will be a fading memory instead of a jarring sight.