There's a place in Wales where raw sewage poured into local waterways for the equivalent of 300 days - almost an entire year.

And Garnswllt, north of Swansea, is not alone.

In fact, untreated waste has been discharging into rivers and streams across Wales, sometimes for the equivalent of weeks or even months.

Read more:The 26 key things that are going to change under government plans for Wales to be net zero

According to Welsh Water some of the worst affected areas last year were in South West Wales with one combined storm overflow leaking for the equivalent of over 300 days in Garnswllt.

The figures for releases from storm overflows in the year 2020 have been published by Welsh Water and the not for profit company has acknowledged that more needs to be done, but warned that this will require "significant additional funding and will take many years to deliver".

Natural Resources Wales has recorded a total of 105,751 spills over the 2020 period, increasing from 73,517 the year before, a rise it attributes partially to more event duration monitors (EDM) which record the number and duration of spills, being installed on the sewerage network.

Some of the discharges this year have led to warnings not to swim at beaches in Swansea and other parts of Wales.

Natural Resources Wales warned people not to swim at a beach in Swansea over concerns of a sewage discharge

With sewer overspills becoming more common as a result of the changing weather and climate, according to Surfers Against Sewage, beaches across Wales are being badly affected with drops in their water quality rating, like happened in Barry.

Just this week a North Wales beach was also issued with a pollution alert after being contaminated by human waste following a sewer discharge from a nearby overflow, as the Daily post reports.

The issue has sparked protests across the country with one 'wild woman' even swimming attached to a coffin in the River Wye in Monmouthshire to make her point about dirty water.

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Recently Welsh Tory MPs voted against amendments to a bill in England aimed at placing more legal duties on water companies to make better efforts to stop sewage leaking into nearby waters. Following a public outcry, the Government made a partial u-turn, agreeing to, "see a duty enshrined in law to ensure water companies secure a progressive reduction in the adverse impacts of discharges from storm overflows".

The initial decision to vote against the amendments was condemned heavily by water quality campaign organisation, Surfers Against Sewage.

Speaking previously chief executive, Hugo Tagholm said: "Record numbers of people are using our beaches, rivers and lakes for health and wellbeing. Wild swimming, surfing, stand-up paddle boarding and much more – our blue spaces have never been a more important public amenity. Yet sewage and agricultural pollution still plague the UK’s rivers and the ocean. Only 14% of rivers in England meet “Good Ecological Status” and, despite investment in the 1990s, the UK is ranked last out of 30 European countries for coastal water quality. In 2020 alone water companies pumped raw sewage into England’s waters for 3.1 million hours.

"In this most important of environmental decades, we urge progressive and ambitious action from government and our elected representatives to end sewage pollution, and restore thriving rivers and coastlines for all. The Environment Bill offers MPs the perfect opportunity to show world-beating action to restore Planet Ocean".

A map of water quality in Wales - a red cross means pollution risk warning in place, green tick means no alert
A map showcasing where sewage is discharged into rivers


To see if your area is affected by sewage discharges, you can visit Surfers Against Sewage or Rivers Trust.

According to 2020 data from Welsh Water, available here, these are some of the worst sites across Wales for discharges from combined sewer overflows.

WwTW stands for Welsh Water treatment works and the figures below show the location of the combined storm overflow, the number of hours and minutes of discharges, and the equivalent time in days.

South West Wales:

Ystradgynlais WwTW - 3062 Hours 30 Minutes - 127 days

Trebanos WwTW - 3676 Hours 30 Minutes - equivalent to over 150 days.

Puncheston WwTW - 4100 Hours - 170 days

Ferwig WwTW - 5045 Hours 30 Minutes - 210 days

Garnswllt WwTW - 7438 Hours 0 Minutes - 309 days

Valleys and South East Wales

Clydach - Station Road - 1269 Hours 30 Minutes - 52 days

Usk Llanbadoc Monmouthshire - 1808 Hours 45 Minutes - 75 days

Newport - Underwood SPS - 1197 Hours 45 Minutes - 49 days

Brynmawr Blackrock - 1818 Hours 30 Minutes - 75 days

Pontypool - Charlesville - 2274 Hours 30 Minutes - 94 days

Cilfynydd WwTW - 2877 Hours 30 Minutes - 119 days

Rhymney Valley Tanks St Mellons - 3973 Hours 30 Minutes - 165 days

North East Wales

NESTON - 1154 Hours 30 Minutes - 48 days

Northop Mold - 1015 Hours 45 Minutes - 42 days

Ruthin / Ruthun (2) - 2383 Hours 45 Minutes - 99 days

Clawddnewydd WwTW - 1727 Hours 15 Minutes - 71 days

Chester Rd Broughton - 2342 Hours 30 Minutes - 97 days

North West Wales

Eg;wusbach - 2548 Hours 0 Minutes - 106 days

Llanffestiniog Works 1 - 4375 Hours 15 Minutes - 182 days

Llanrwst Conwy - 1538 Hours 30 Minutes - 64 days

Rhos Cottages Capel Curig - 4186 Hours 30 Minutes - 174 days

Llanelltyd - 2085 Hours 15 Minutes - 86 days

Abererch - 4288 Hours 0 Minutes - 178 days

Mid Wales

Brecon WwTW - 2099 Hours 15 Minutes - 87 days

Sennybridge Army Camp Sennybridge - 1660 Hours 15 Minutes - 69 days

Beulah Powys - 2957 Hours 15 Minutes - 123 days

Llanwrtyd Wells Powys - 2592 Hours 45 Minutes - 108 days

Pontneddfechan Neath - 2754 Hours 30 Minutes - 114 days

Swansea - Abercrave - 1121 Hours 15 Minutes - 46 days

Check the weather for your area:

A spokesperson for Welsh Water said: "As a not for profit company so closely linked to the environment, we are very aware of the impact our operations can have on our surroundings and take our environmental performance very seriously. This includes the operation and maintenance of our extensive wastewater network which includes more than 830 wastewater treatment works and over 37,000km of sewers.

"We have invested £8.1 million in improving the monitoring of the CSOs (combined storm overflows) since 2015, and now have spill monitors on over 90% of all of our CSOs – more than any other water company. These monitors record the number and duration of spills and this data is published on our website allowing us to develop investment cases to make further improvements and also to provide real time spill information for key bathing waters to interested bodies, including Surfers Against Sewage.

“As our profits don’t go to shareholders but instead are reinvested to improve our services, over the past 20 years we have invested over £1billion in our entire wastewater network. We know however that there is still further work to be undertaken and that is why we are investing £765 million between now and 2025 on further improvements to our wastewater system. This includes around a £100 million programme to improve priority CSOs.

“We would add that testament to our investment to date in our wastewater network is that in 2021, Wales secured 45 Blue Flag beaches and marinas – which is significant as Wales only has around 16% of the UK’s coastline but has around a third of the Blue Flags.”

A spokesperson for Natural Resources Wales (NRW) said: "During AMP7 (a planned programme of management of the network stretching from 2020 to 2025), the data collected via EDM is informing development of a DCWW (Dwr Cymru Welsh Water) programme of targeted investment of over £30m aimed at reducing environmental impacts from assets identified as ‘high’ spillers ( more than 40 annual spills) on inland waters where it is cost beneficial do so.

"NRW is working closely with DCWW on this programme to ensure investment is targeted appropriately. We are also requiring water companies in Wales to target investment at increasing capacity and storage, and to carry out additional monitoring so that we can better understand issues that arise and wherever necessary carry out appropriate regulation."

Sewage being spilled into waters is far from an issue unique to Wales, however, with cases of thousands of dead sea creatures being found on English beaches, and an investigation into whether pollution is to blame.

Drone footage going viral on social media has also shown untreated brown waste pouring into Langstone Harbour in Hampshire.

The cost of fixing the entire sewerage network to prevent such spillages happening at all has been estimated at anything between £150 billion and £600 billion.

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