However, visitors are still being urged to observe social distancing and follow specific guidance and signage at individual sites.
The move follows the latest Government advice which relaxes the previous restrictions on driving to the countryside for exercise.
While the car parks and gated entrances are now open, toilets and other facilities on site will remain closed for the time being in order to maintain safe distances between visitors. Car park pay-stations will not be in use to help minimise any physical contact.
Paula Steer, United Utilities’ director responsible for health and safety and estate management, said: “We know how much people enjoy visiting the beautiful countryside around our reservoirs, and it will come as welcome news that the Government’s lockdown restrictions are beginning to lift.
“It’s important to remember that this is a phased approach and we are relying on visitors to be public spirited. Please be courteous to our employees and local residents – reservoirs are their workplace and home – and be prepared for it to be busy. You may struggle to find a parking space, and if that happens it may be better to come back another day rather than block narrow roads or put yourself or others at risk in crowded areas.
“We are all in this together, and anything you can do to ease the pressure, like taking your litter home with you, would be much appreciated.”
Visitors will see signage at the reservoir sites reminding them to observe a two-metre social distance from those outside their household. Barbecues, fires and camping are not permitted and swimming is not allowed in the reservoirs.