Emergency services were called this morning after receiving reports of a woman in a reservoir.
The incident happened at Pebley Reservoir in Harthill.
A Derbyshire police spokesman said: “We were called at 9.10am after someone saw a woman in the water.
“She later came out.”
The water rescue unit and two fire engines from Chesterfield were called to the scene but returned to their base after the woman got on to dry land.
An ambulance is currently on its way to the scene.
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