Northamptonshire County Council and Anglian Water are asking people not to travel to Pitsford Water this bank holiday weekend and during the half term break.
There has been a significant increase in the number of people visiting the park following the changes to the national lockdown restrictions made by Government on Sunday 10 May, which allow people to travel to exercise, however the park remains closed.
Anglian Water are working on plans to reopen Pitsford Water soon, once safety and social distancing measures have been put in place.
Northamptonshire County Council Leader, Matt Golby, said: "Anglian Water has closed Pitsford Water to protect its staff, volunteers and the public and we have been advised that it will remain that way for the foreseeable future.
"We recognise that after a number of weeks at home people are keen to exercise in different surroundings. But many visitor attractions, bars, restaurants and coffee shops are still closed. It is therefore important that people do not travel to Pitsford so we can continue to protect our vulnerable residents from the virus and reduce the pressure on our emergency services and the NHS."
Jake Williams, Head of Parks and Conservation for Anglian Water, said: “We know our leisure attractions are loved by many and protecting the health and safety of our colleagues and visitors is our top priority.
"Balancing the needs and wishes of all our active communities is always a challenge and we are all keen to get back to some sense of normality. We are working on plans to reopen our parks as soon as we are confident we can do so safely, meeting all the guidance on social distancing.
"If you were hoping to visit soon please postpone as we will not be open and all tracks and car parks are closed. Thank you to everyone who has been supportive during this time, we look forward to welcoming you back in the near future. "