Walthamstow Reservoirs are set to reopen this week following a five week closure.
Thames Water took the preventative measure to close the fishery after a carp virus was found in the reservoirs following the death of a number of fish.
Now, the reservoirs will return to normal on Wednesday, June 21.
Following an investigation by the Environment Agency and the Fish Health Inspectorate, it was discovered the rare Carp Edema Virus was the reason for the fish deaths.
Not much is known about the virus, but it’s believed to originate from Japan, with more research being carried out to find the causes and symptoms.
Will Barnard, Thames Water fisheries manager, said: “Once again, we’d like to thank our customers at the fishery for their patience and support over the last few weeks.
“We’re relieved to be opening again and will now concentrate our efforts to getting reservoir 1 back to its previously great standard.
“It’s important our users heed all the advice regarding bio security as we really don’t want to risk even the slightest chance of passing the virus to any other fisheries.
“The Environment Agency is happy about our current bio-security measures and the rangers will be even more vigilant when checking for dry nets.”
Normal opening hours will remain from Wednesday onwards.