Despite the wettest January for three years more rain is still needed to fill the county's reservoirs.
Southern Water said August and September had been the driest period since records began in 1873, leaving water levels extremely low.
Even though many areas are on flood alert, more rain is needed to replenish supplies.
A Southern Water spokesman said: "The reservoirs are recovering well following the very dry autumn last year and most have now reached the average level for this time of year.
"However, groundwater resources, which are used widely in Sussex, are still below average and we need the rainfall to continue to ensure these are refilled as much as possible ahead of the spring when demand starts to increase.
"Southern Water is working hard to ensure water supply is as secure as possible for this spring and summer and urges customers to continue their efforts to use water wisely in homes and gardens."
Bewl Water on the Kent/Sussex border and Darwell Reservoir, near Battle, are both more than 90 per cent full.
Powdermill Reservoir, near Hastings, and Weir Wood, near East Grinstead, are more 80 per cent full, although still below their average levels.
Southern Water customers can call 0845 278 0845 for a pack on water-saving tips for the home and garden.
Friday February 06, 2004
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