Where Mexico City's sewage ends up In most capitals, discharging waste is far easier and cheaper than providing clean water, but Mexico City seems determined to make life difficult for itself.
The city has two sewer systems, one for runoff and one for sewage, and when rainfall exceeds 50mm/hour the water is diverted automatically into the sewage channels, which fill up and have to be diverted into the sea, meaning raw sewage ends up in the environment without being treated.
If sewage ends up in the sea, the wipes are washed on to beaches.
The city's sewage system was built in the 1860s, during the Victorian era, and is so old that it can no longer cope, and raw sewage ends up in the Thames.
We should not try to ban or overlook this kind of speech, whether it comes out the sewage end of Glenn Beck's Web site, or from a member of the European Parliament.
New sewage works ended the regular dumping of raw effluent into the water - a damaging practice that encouraged bacteria to use up all of the water's essential dissolved oxygen.
Instead, said Aylard, engineers had to decide whether to block the built-in sewage overflow into the Crane, without knowing where the raw sewage might end up if they did.
Although American communities generally try to manage their waste in a sanitary way, our sewage systems are far from perfect, and as a result raw sewage can end up flowing straight into the seas rather than passing through water treatment plants.
"It's completely unacceptable that sewage can end up in the main river of one of the world's richest cities.
