Plans for a £100m new reservoir in Kent, abandoned in the 1970s, have been revived.
Mid Kent Water already owns some land earmarked for the reservoir
Mid Kent Water plans to build the mile-and-a-half-long reservoir on land at Broad Oak, near Canterbury.
A spokesman said the reservoir was needed because of increased use of water and plans to build thousands of new houses in Kent.
When plans were drawn up to build there in 1974, they were opposed by many locals and abandoned following a public inquiry.
The proposals were contained in Mid Kent Water's draft five year business plan, released on Monday.
Two valleys would be flooded and a dam built to create the huge reservoir.
Mid Kent Water spokesman Trevor Bishop said the firm was expecting a 29% increase in building of new houses in Kent over the next 30 years, which would increase the need for water.
He also said more people had equipment like power showers and jet wash systems which used a lot of water, while environmental legislation meant the firm had to reduce the amount of water taken from some existing sources.
He said: "Kent's moved on a great deal in the last 30 years and effectively there's three key reasons which drive the need for this major resource for Kent.
"The reasons weren't there 30 years ago and we believe these are compelling reasons now.
"It's essential that Kent plans long-term for its water supply."
'A big shock'
Mid Kent Water owns some of the farmland and houses which would have to make way for the reservoir, having compulsorily purchased them in 1974.
Residents of Tyler Hill, the village which would form one end of the reservoir, said they planned to oppose the scheme again.
Penny Reilly, who founded the protest group in 1974, still lives locally.
She said: "It's a big shock. We wondered why they haven't sold so many of the properties that they bought up.
"But we never actually thought a really expansionist and extravagant scheme of this kind would reappear."
The Environment Agency said the Broad Oak scheme was just one of many options put forward by water companies.
It said it would not be allowed to go ahead unless it was satisfied that problems with leakage had been solved and Mid Kent Water had looked at giving all homes water meters.