THE Environment Agency is investigating a pollution incident that has affected a stretch of river several miles long in south Tynedale.

The investigation follows reports of polluted water in the Hartley Burn at Halton Lea Gate last week, the cause of which remains unknown.

Agency officers found that sediment was affecting at least 6km (3.7 miles) of the watercourse.

It is believed that a period of heavy rain last week caused the unknown sediment to be washed into the river, turning the water in Hartley Burn dark and murky.

The burn, which is a popular spot for fishermen, flows into the South Tyne, and it was feared that the pollution could affect areas were salmon are known to spawn.

At this stage there is no evidence that the pollution has had any detrimental effect on fish or wildlife in the area. But Sophie Wild, of the Environment Agency’s land and water team, said the cause and potential impacts of the pollution was still being investigated.

She said: “We received a report on Monday of pollution in the Hartley Burn at Halton Lea Gate following a period of heavy rain.

“Samples have been taken and ecology and fisheries experts at the Environment Agency have also conducted surveys to assess what impacts this incident may have had on the watercourse.

“Further investigations are ongoing into the source, cause and impact of the pollution.”

Northumberland County Council has been in contact with the agency regarding the pollution, but is remaining tight-lipped over the issue.

A spokesman for the council said: “We are in contact with the EA which is carrying out an investigation.

“Until that is complete it would be inappropriate to comment further.”

Anyone who is concerned about pollution in watercourses can report the issue to the Environment Agency on 0800 807060.