SCOTTISH WATER has now lifted the restriction on the remaining 20 properties in Whalsay that have previously been advised not to drink or cook with the water supply.
Around 140 properties were initially given bottled water to use earlier this week, after high than normal levels of aluminium were discovered in the water supply.
This is despite Scottish Water recently finishing work a £5 million treatment plan in Whalsay, with old networks and pipes interfering with the new supply.
A Scottish Water spokesman said: "Residents in the 20 addresses in Vaivoe and Skaw will be receiving letters later today but we are delighted to confirm the levels of aluminium in the supply are now at acceptable levels and customers can now drink or cook with the water.
"We will continue to flush the water mains over the weekend and take samples to ensure the levels remain acceptable going forward.
"We will also continue to be in touch with colleagues at NHS Shetland and can ensure Whalsay residents public health will always be our main priority at Scottish Water.
"Our teams have worked hard to resolve this issue as quickly as possible and we want to thank those affected customers for their patience and understanding over the last few days."