"Urgent action" must be taken to tackle a sharp rise in sewage dumping in Welsh rivers, with more than 105,000 incidents reported in 2020 alone, according to a report.
The Senedd’s Climate Change Committee said it "notes with concern how frequent these sewage spills are and how much they have increased in recent years."
In 2016, there were just under 15,000 incidents of untreated sewage being dumped into Welsh watercourses, recorded by 545 monitors in Wales.
By 2020, despite the number of monitors having only increased to 2,000, there were more than 105,000 such incidents.
When wastewater treatment works are overwhelmed with water following extreme rainfall, they are allowed to release untreated sewage into rivers via ‘storm overflows’ to manage the situation.
However, the figures listed in the report do not include 'unpermitted' storm overflows, or overflows that are not monitored by water companies - meaning the real number of sewage spills is much higher.
The report puts forward a series of recommendations to protect Welsh waterways, which it says should include targets and timescales for the reduction of sewage discharges.
Climate change minister Julie James MS has been given six months to work with water companies to address the concerns raised, before she will be asked to appear before the committee.
'It cannot be right that a parent is scared to let their child swim in a river in Wales for fear of pollution and human waste'
Llyr Gruffydd MS, Chair of the Climate Change, Environment and Infrastructure Committee, said: “Storm overflows should operate infrequently and in exceptional weather conditions - but that is not what’s happening.
"Instead, we’re seeing the numbers of incidents rising sharply with repeated reports of sewage in our rivers.
“It cannot be right that a parent is scared to let their child swim in a river in Wales for fear of pollution and human waste. The public is rightly outraged by what it is witnessing - it is simply unacceptable.
“The Welsh Government must listen to the evidence we’ve collected and take immediate action to ensure that the number and volume of these discharges are reduced.”
The committee is also calling on the two water companies operating in Wales - Dŵr Cymru and Hafren Dyfrdwy - to report on discharges from storm overflows “within an hour of the discharge beginning”, which is already a requirement placed on water companies in England.
The report goes on to say that “if they cannot match this standard, both companies should explain why.”
Dŵr Cymru told the committee: “It’s not where we want to be. We clearly can see the number of discharges from storm overflows is a really large number, and that’s not coming down.”
Hafren Dyfrdwy said: “We are committed to continue to drive performance, improve performance, and accept that there’s far more that the water industry can do.”
A Welsh Government spokesperson said: “We welcome the committee’s interest in this important issue and look forward to reviewing its report and recommendations.
“We need to take an approach to improving water quality which is best suited for the specific circumstances in Wales.
“Reducing pollution impacts from all sources is a priority for us and we are currently working on sustainable, nature based, solutions to achieve this.
“We are also working with Natural Resources Wales to encourage water companies to come up with plans to develop a more resilient wastewater and drainage infrastructure to deal with current and future pressures caused by factors including population growth and climate change.”
The Welsh Government added that improving the water quality of our rivers is a "complex and long-term" task, with other factors playing a part in river pollution.