“At low summer levels, when we get blockages, the Combined Sewer Overflows are discharging into the river…”
Dai Roberts,of the Riverfly Partnership, talks about how – at low summer levels – the antiquated sewerage system is continually blocked and Combined Sewer Overflows are discharging into the river, carrying human and industrial waste. To fix the sewerage system is too costly but Dai and his colleagues are monitoring the invertebrates on the river bed.
Dai Roberts: Dai Roberts, I’m with the Riverfly Partnership and also with the South East Wild Rivers Trust. Now one of the problems, we’ve got, particularly with low summer levels, is the antiquated sewerage system which is continually being blocked and flood levels, the CSOs are overflowing, which is what they’re designed to do. But at low summer levels, when we get blockages, the CSOs are discharging into the river, so it’s not only carrying human waste, but it’s carrying commercial and industrial waste as well, which obviously has a very detrimental effect on the entire ecosystem of the river. Welsh Water are not in a position to remedy the antiquated sewerage system. It’s going to cost them billions and they’re not going to do it. They can’t block the CSOs because, if they do, they’re going to be back filling and flooding people’s houses, which they’re going to find unacceptable. We use invertebrates, river fly invertebrates, as biological indicators and the numbers are disastrous. They’re nothing like they should be and nobody knows what the factories are, at the top of the valley, are discharging into their sewerage systems. Nobody knows what’s consented and not consented. Even if it is consented, it’s consented that it goes straight through to the sewerage works, rather than into the river. There are illegal discharges. We had a prosecution, a few years back, of a company, [Tribana?] Bark, who were building timber frame houses. They were using synthetic pyrethroid, permethrin, as a preservative, an insecticide, in their timber. They weren’t over fond of storing their materials under cover. They weren’t particular over their sawdust discharges. That resulted in them being prosecuted and the factory shutting. NRW is not in a position to monitor as they used to. They don’t have the resources.