Manx Utilities has reported a spike in demand.
The news comes after one of the hottest weekends of the year.
The company said overall stocks are still healthy and there are no immediate plans for a hosepipe ban.
The tweet from the water company came after an image was posted by Peter Killey from Manx Scenes Photography showing low water levels at Injebreck Reservoir in West Baldwin.
A Manx Utilities spokesman said Sulby reservoir is currently pumping stocks to the area.
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