The areas of the UK where the most raw sewage is dropped into rivers and seas are all in Wales, data shows. Of the top 10 places which see the most sewage dumps, five are in Wales including the top three locations.
Campaigners fighting to stop raw sewage being discharged into Britain’s waterways have used publically available data to compile a map showing the areas of the UK where the most sewage dumps have taken place, the hours of sewage as well as the year on year change.
The map is broken down by constituency and made up of data from 2021. WalesOnline has asked Welsh Water several times in the past for up-to-date figures for discharges in 2022 but have been told that information is not yet available. You can find the map published by Top of the Poops here.
Read more: Every place raw sewage is dumped into our rivers and exactly how often it happens
Earlier this year there were warnings by health boards across the country for people to avoid certain beaches after sewage was dropped into the sea after the heatwave which caused uproar. At one point more than 50 beaches were impacted.
While there is currently no data for 2022, in 2021 there were at least 470,000 "sewage spills" in England and Wales according to the figures from Top of the Poops. Combined, they add up to over 3.4 million hours across the year.
These figures show that in Wales, the area with the highest amount of sewage dumps is the Preseli Pembrokeshire constituency with 6,754 dumps equating to 79,501 hours of sewage - up by over 6,000 hours from 2020. These occurred over 88 sites with the Aberach Stream being worst affected with 366 instances alone.
Secondly is Carmarthen East and Dinefwr with 7,456 dumps totalling 71,831 hours. Compared to other areas this is down by over 5,000 hours on the previous year. Here, across 97 sites, part of the River Teifi is worst impacted.
Third on the top 10 list is Dwyfor Meirionnydd with 6,952 dumps over 68,545 hours. This is down over 11,000 hours on 2020. In this area Nant Brisgyll is the worst affected with over 300 dumpings. Carmarthen West and South Pembrokeshire and Ceredigion constituencies also featured in the 10 areas where the most raw or partially treated sewage was dumped into the rivers and seas.
Why is this happening?
Welsh Water said that the reason the areas with the highest number of sewage spillages are in Wales is because these are the wettest parts of the British Isles and therefore it is unsurprising more sewers get overwhelmed. They also said that they had more monitors on their systems than other providers and so could provide more data.
Welsh Water control more 36,000 kilometres of sewers that take your dirty water away before it's cleaned at local treatment works and the clean water released into rivers and seas. Unfortunately, most of this network was built over 100 years ago during the Victoria era. Estimates suggest it would cost between £9 billion and £14 billion to remove CSOs completely from the network and would take decades. Welsh Water say it would make water and sewerage bills unaffordable.
Though it is obvious how the sewers get overwhelmed during heavy rain and storms, it begs the question why there are so many releases during dry weather. According to Welsh Water, this is mainly due to blockages caused by flushing objects like nappies and wet wipes. These cause blockages which in turn case a backlog that is then released into rivers before it can go into homes.
It is worth noting that there is no "eject button" that anyone presses to release this wastewater. It is an automatic release built into the system when it reaches a certain pressure.
What do Welsh Water say?
A spokesperson for Welsh Water said: "We submit our spill numbers annually to our regulator Natural Resources Wales as is the current required process and we are fully transparent with the data as it is always available to view on our website by anyone at any time.
"It is important to be clear from the outset that the higher spills numbers from our Combined Storm Overflows (CSOs) does not mean that Welsh Water is a poor performer in this area and the numbers must be viewed in the context of two key facts.
"Firstly, Welsh Water is committed to protecting bathing and river water quality and has invested over £8 million on installing monitors on its CSOs to record spill numbers. The company now has monitors on 99.5% of its CSOs which exceeds the coverage of other water companies. This means that Welsh Water has much more data to report on its CSOs to its regulators and so it’s unsurprising that it records larger numbers of spills than others.
"Secondly, due to its geographical location on the British Isles, Wales naturally receives more rainfall than other parts of the UK. As CSOs are designed to operate during heavy rainfall to help protect communities from flooding, our CSOs operate more frequently. Snowdonia National Park for example is amongst the wettest places in the UK and to bring this to life, in February 2020, Capel Curig saw 224mm of rain for the month compared to the UK average of just 97mm of rain. Currently the average spill number for Welsh CSOs is around 33 times per year. If we had the rainfall of Cambridge for instance, the average spill number would be 13 times per year. Their operation is a function of the rainfall we receive in Wales.
"We recognise however that with environmental legislation tightening and customer expectations changing, more needs to be done. Removing CSOs from our system is not an option but what is in our control is the ability to target investment to CSOs which have the biggest impact so that we can improve their performance. That is why we are investing £936 million to 2025 on further improvements to our network.
"Welsh Water has always taken its responsibility for operating CSOs responsibly and invested more than £1 billion as testament to this over the years. This has delivered real improvements and helped ensure that Wales has over a third of the UKs Blue Flag beaches while only having 15% of the coastline."
Read next:
- Raw sewage released into UK seas and rivers 150 times in a year
- Nine Welsh beaches named among the top 50 in the UK by the Sunday Times
Sewage has been released into the sea at Welsh beaches after the heatwave
Homeowner with raw sewage seeping from garden abused by passers-by over foul smell
Hundreds of pipes ‘could be dumping sewage illegally’, investigation finds
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