water Detroit
Bottled water is delivered to a school after elevated lead levels were found in Flint's water supply REUTERS/Rebecca Cook

The largest city in the US state of Michigan, Flint, has declared a state of emergency due to lead in its drinking water after people complained about the taste, smell and appearance of the fluid.

Children in the city, which has a population of 120,000, have elevated levels of the metal in their systems which have been attributed to the water supply. Exposure to the heavy metal can cause behavioural problems and learning disabilities in children.

Federal officials have begun an investigation as the Governor of Michigan, Rick Snyder, declared the state of emergency for Genesee County. Flint had switched from Detroit's water supply to the Flint River in 2014 in a cost-cutting exercise.

It was supposed to be a temporary measure for the city 70 miles north of Detroit, while a huge pipeline was built from Lake Huran to the city.

But the people of Flint noticed the water had a strange colour and studies revealed that lead levels were ten times higher than average. According to CNN, a hospital in the area reported that the percentage of children with elevated lead levels nearly doubled after the switch.

In October, officials reversed the decision and ordered the use of Detroit water once more. In November 2015, Flint citizens filed a lawsuit against Snyder, the state of Michigan, the city of Flint and other state and city officials.

The health effects listed on the law suit included skin lesions, hair loss, high levels of lead in the blood, vision loss, memory loss, depression and anxiety. Only last week Snyder was forced to apologise for the debacle and Michigan's top environmental regulator resigned after his agency was blamed.

The state of Michigan earmarked $10.6m (£7.2m) to reconnect the city to the Detroit water supply and to install filters, testing and other services. The city has requested $50m (£34m) in aid, $45m (£30m) of which would be to replace 15,000 lead service lines.