The Environment Agency says oxygen levels in Grantham Canal have now returned to normal after the deaths of hundreds of fish.
They were first called to the waterway yesterday and found oxygen levels at around 20%. Since then they have been pumping chemicals into the water to increase the oxygen concentration.
Test have now showed that the oxygen has returned to its normal level. It is believed the recent hot weather, leading to an increase in weed growth, had caused the drop.
Reuben Page from the Environment Agency has been explaining what the situation was when they were first called to the canal yesterday and what work they have been carrying out to deal with the problem.