People in England and Wales could be forbidden to fill pools and clean patios with a hose during a drought under plans to toughen hosepipe bans.
Restrictions could cover many aspects of domestic water use
The bans already cover washing cars and watering gardens with a hosepipe.
School pools and pools for medical use will be exempt from the rules next spring, but water companies may forbid the use of a hose to wash windows.
Environment Minister Phil Woolas said the existing law was inconsistent and left gardeners feeling "singled out".
The dry weather of 2005 and 2006 led to empty reservoirs and hosepipe bans that affected about 13 million people.
Mr Woolas said: "We saw an extreme drought in the south east then, and outdated legislation meant gardeners couldn't water their plants with a hosepipe, but their neighbours could power-wash their patios or fill swimming pools.
"That situation was clearly inconsistent and illogical."
The changes will introduce a "discretionary use ban", leaving it up to individual water companies to decide which water-related activities to prohibit.
Firms will not have to consult ministers in order to act and could also stop people using hot tubs and jacuzzis, operating ornamental ponds and fountains and using pressure hoses.
But gardeners maintaining registered collections of plants will be allowed to water them.
Mr Woolas said the country had to rely on individual "goodwill" during times of drought.
"But that goodwill can disappear very quickly when there are blatant anomalies and people feel they are being unfairly singled out," he added.
Earlier, Mr Woolas told the Sunday Telegraph: "The plain fact is we can no longer use drinking water for luxuries at times of crisis.
"These new measures may seem harsh to some but future droughts, especially in southern England, are inevitable and we have to act.''