Claims that a water firm failed to deal with rising demand and climate change have been made at a hearing into Southern Water's drought measures.
Bewl Water reservoir reached its lowest ever level in late 2005
Southern Water is asking the Environment Agency for permission to boost reservoir supplies by taking water from the River Medway.
The Campaign to Protect Rural England said the firm needed a better strategy.
Southern Water has said the move comes after a thorough inquiry and will protect customers' supplies in 2006.
A decision on the drought permit application is expected in two weeks' time.
The application was made after Bewl Water reservoir on the Kent and Sussex border reached its lowest level since it was built in 1975.
Southern Water has said there will be "problems with water supplies in the summer" if the drought permit is not granted and that the firm believed there was "a good balance between supplying water and minimising impact on the environment".
But Graham Warren, from the Campaign to Protect Rural England, said: "This reflects a failure on the part of the company to put in a competent or comprehensive strategy to address rising demand, the impact of climate change and other influences producing an increasingly stressed state of water resources."
Hosepipe bans imposed during the summer are still in place across the South East as the region suffers its worst drought since 1976.
Bewl Water reservoir supplies people in Medway and in an area stretching from Thanet in Kent to Hastings in East Sussex.