The community lacks access to water and fertiliser so they often use waste water to fertilise crops.
It announced its 50th investment on Wednesday – £2m to extract heat from waste water to provide energy for buildings in Scotland.
Rain water captured by drain sewers on city streets flows into the same pipes that bring waste water to sewage treatment plants.
The bank announced its 50th investment on Wednesday: a £2m deal to extract heat from waste water to provide energy for buildings in Scotland.
The company is also experimenting with using reeds to decontaminate industrial sites in Sardinia, and using waste water to irrigate plantations.
The Chicago area has 1,300 units of local government, including six counties, 113 townships, 270 municipalities, 306 school districts and 558 special districts that do everything from treating waste water to fighting mosquitoes.
But legislators and environmentalists are concerned about the state's proximity to Pennsylvania, a shale gas fracking hot spot that sends some drill cuttings and waste water to nearby states, including New York, for processing and treatment.
Ian Michaels, a spokesman for the department, said the agency believed that it was inappropriate to apply Clean Water Act rules intended to regulate sewage and industrial waste water to the conveyance of untreated, natural drinking water.
It seems quite likely, some other employees and local residents said, that the company had diverted waste water to avoid paying fees to have it processed, and that pending inspections prompted the company to restore the flow.
But technologists have been slower to exploit the vast amounts of ambient heat available in the atmosphere, or produced by machinery.True, some simple forms of heat recycling have been around for a while: using heated waste water to warm flooring and melt ice on driveways, for example.
"We did leave a letter of notification with the occupants informing them of the illegality of allowing waste water to run into the street or onto another property," Ms. Mullin said, adding that if the problem recurs, the letter writer should immediately notify the department by calling (212) 44212666.
