TOLEDO, Ohio (AP) — Three years after toxic algae in Lake Erie tainted the tap water for more than 400,000 people in Ohio and Michigan, many are still skittish about drinking it.

Just last week, rumors of another "do not drink" advisory emptied out the bottled water sections in Toledo-area stores.

The city's mayor has been assuring residents that water is tested repeatedly and is safe to drink. But she's also asking President Donald Trump for help from the federal government in cleaning up Lake Erie.

Toledo Mayor Paula Hicks-Hudson told the president in a letter sent last week that there's something very wrong when rivers and lakes are turning green.

Scientists largely blame farm fertilizer runoff and municipal sewage overflows for feeding the algae in the shallowest of the Great Lakes.

Copyright 2017 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.