The water in a section of the Swansea Canal turned white at the weekend after a “pollution incident” involving a nearby roadworks.
People walking on the canal towpath next to the Mond Community Centre in Clydach noticed that the surface of the water had turned a “milky white” colour.
Ray Lockyer, a member of the Pontardawe and Swansea Angling Association, went to assess the danger to wildlife in the canal.
“It looks terrible, the whole stretch had turned white like there was sediment in the water. When I went there yesterday morning it looked just like milk,” he said.
“It doesn’t seem to be harmful to anything in the canal though, there were no dead fish and the Mallards and Moorhens were paddling away and didn’t seem to be affected,” he said.
A burst water main from the maintenance works on Ynyspenllwch Road, outside the Mond Community Centre, appears to be the source of the “pollution.” The cloudy water can be seen running off the road into the canal.
Clydach Councillor Gordon Walker said: “I’ve had people calling me left, right and centre regarding the colour of the water. You don’t want it to be too cloudy with dirt or dust because it could kill a lot of fish, so it’s got to be sorted pretty quickly.”
Mr Walker, who is also Chairman of the Swansea Canal Society, said he had been in contact with Welsh Water about the burst pipe as well as voicing concerns about how long the works were taking to complete.
He added that the disruption was causing “tremendous delays” and long queues for drivers as the road is down to one lane with temporary traffic lights in place.
Canal and River Trust, who are responsible for the maintenance of the affected section of the Swansea Canal, said that a burst Welsh Water pipe was the source of the run-off that was entering the canal, and that it may take a few more days to fix.
A Welsh Water spokesperson said: “We are aware of a report of discoloured water in the canal in Clydach, which has happened as a result of a burst water main in the area. We have liaised with Natural Resources Wales over the matter and continue to work with them to monitor and mitigate the situation.
“This is a challenging repair due to the nature and location of the burst, however there is currently no interruption to customer supply.
“We are working hard to complete a repair as quickly as possible, and we apologise for any inconvenience to local residents while we work in the area, and thank them for bearing with us while we carry out this necessary work.”
Natural Resources Wales has confirmed that the leak comes from a water main for drinking water, not a waste pipe, and the discolouration is a result of silt picked up between the leak and the waterway.
Hamish Osborn, Environment Team Leader for Natural Resources Wales, said: “We have attended a pollution incident in a canal near Clydach and have found that a burst water main has caused sediment to enter the watercourse.
“The sediment has caused discolouration of the water in the canal but we do not believe this presents a risk to human health.
“Dwr Cymru/Welsh Water are working on fixing the burst water main and are taking steps to minimise the amount of sediment that enters the watercourse.
“Once repair work has been completed we will reassess the impact of the incident on the water in the canal.”