All swimming spots › the Vale of Glamorgan, Wales
Can I swim at Cold Knap Barry?
the Vale of Glamorgan, Wales · Coastal
Checking…Seaside Award
Before you get in
A red flag means do not go in, whatever this page says.
If you get into trouble, float on your back until the cold shock passes. Full advice below.
In an emergency call 999 and ask for the Coastguard, or 112 in the Republic of Ireland.
Water quality today
The last fortnight
What this verdict covers
Independent site, not an official one. This verdict is about water quality. It does not tell you whether the water is safe to get into today.
How it has been rated
The annual classification for 2021 to 2025. Each one is calculated from samples taken over up to four bathing seasons, so these overlap and none of them describes today.
Every sample, 2022 to 2026
45 samples, 2022 to 2026. The highest E. coli count in them was 380 per 100ml, on 11 September 2025; the standard for Excellent is 250 or below and for Good 500 or below.
One bar for each sample, oldest on the left. The taller the bar, the more E. coli that bottle held.
The scale is the same on every beach on this site, which is why a clean beach looks flat — the bars are measured against the standard rather than against that beach’s own worst day. Hover or tap a bar for that day’s figures. A single count over a line is not a failed beach. The classification is worked out as the 90th and 95th percentile of four years of samples, so one bad morning does not decide it — and one good morning does not either.
What these bacteria mean for you
Neither one is what makes people ill by itself. They are markers: they live in the gut, so finding them means sewage or animal waste has reached the water, and whatever else came with it is likely there too.
The usual way to catch something is swallowing the water, and the usual result is a stomach upset. Ear, eye, chest and skin infections are the other common ones. Putting your head under and swimming with an open cut both raise the odds.
The riskiest time is the day or two after heavy rain, when storm overflows discharge and rain washes off farmland — including at beaches rated Excellent for the rest of the season. That is the whole reason this page shows you rainfall and discharges alongside the grade.
Cold Knap Barry was rated Excellent for 2025, the highest of the four grades in the Bathing Water Regulations. That grade comes from bacterial samples taken over several seasons, so it describes the beach's record rather than the water on any given day.
Natural Resources Wales issues a daily pollution risk forecast during the bathing season for 15 of Wales's 114 bathing waters, and Dŵr Cymru publishes live storm overflow status.
The regulator records this as a bathing water whose quality can be affected by heavy rain, which is why rainfall in the last 24 hours is shown above.
The rest of its file
What the regulator holds for this place. None of it describes the water today.
- Water
- Coastal
- Area
- the Vale of Glamorgan, Wales
- Monitored outfalls within 5km
- 34 (nearest 0.5km)
- Affected by heavy rain
- Yes, per the regulator
Cold Knap Barry holds Seaside Award for 2026.
- Seaside Awardthe UK award for a clean, safe, well-managed stretch of coast
Awarded by Keep Wales Tidy, 2026. An award is given once a year and says nothing about the water this afternoon — that is the verdict above. What a Blue Flag actually means.
Sea, wind, tide and weather
The sea and the weather here today and for the week ahead. Not the water quality verdict above.
Today
Rain, the week behind and ahead
The weather for the week ahead
Where it is, and what discharges near it
Directions to this bathing water
That is Natural Resources Wales’ sampling point, which is at the water rather than at a car park. Your maps app will take you to the nearest road it can reach.
The nearest mapped car park is about 160m away in a straight line (Knap Terrace Car Park). That is not a walking distance: OpenStreetMap knows where the car park is and nothing about the path, which may be longer, steeper or not there at all. It is tagged as free, as the mappers wrote it.
What is mapped at this beach
- Toilets about 60m away — step-free
- Romillys Two about 360m away
Straight-line distances from OpenStreetMap, not walking distances, and only what volunteers have mapped — something missing here may still be there.
Getting here without a car
- Nearest bus stop Marine Lake (opp), Lakeside, about 350m away
- Nearest railway station Barry Rail Station, 1.1 km away
Straight-line distances to where the stop or station is, from the national registers of them. That a stop exists is not a promise that a bus calls at it — timetables are somebody else’s data and this page does not read them, so check the operator before you rely on it.
What the regulator says about this beach
From Natural Resources Wales’s published bathing water profile for 2014. It describes the place and its catchment, not today’s water — and this profile is 2014, so treat the history and the works described in it as that old.
The beach itself
The bay, located adjacent to Barry Old Harbour, is primarily a steeply sloping stone and pebble beach, with sand exposed at low water only. The beach faces south west towards the Bristol Channel, backed by cliffs at the north end, with a promenade at the south end towards Cold Knap Point and the highly urbanised town of Barry in the surrounding area. The water quality sample point is located at the centre of the bay, opposite the car park.
What drains into it
The natural drainage (hydrological) catchment surrounding the bathing water is highly urbanised with commercial buildings in the immediate vicinity. The River Cadoxton meets the sea four kilometres east of the bay and may influence bathing water quality, depending on tidal currents and weather conditions. The River Cadoxton drains a large and diverse catchment. In the lower reaches, there is a combination of large residential areas and heavy industry, along with several small industrial estates. Towards the top of the catchment the land is largely rural, which is not intensively farmed.
More from the profile
What has been done about it
Dŵr Cymru Welsh Water has invested a significant amount of money to upgrade the sewerage infrastructure in the Barry catchment, under The Asset Management Programme. The five year rolling programmes are developed by Natural Resources Wales and Dŵr Cymru Welsh Water to bring about water quality improvements and comply with environmental legislation and European directives. Dŵr Cymru Welsh Water’s Barry Town West Works, near Cold Knap normally transfers effluent to Cog Moors Sewage Treatment Works to the east of Barry for treatment. In high flow conditions, this treatment works discharges directly to the Bristol Channel, via long and short sea outfalls, located off Cold Knap Point, to the east of Cold Knap Bay. The effluent discharged is screened to minimise its environmental impact and to protect the bathing water quality.
The council's part
Natural Resources Wales and the Vale of Glamorgan Council have been working together to improve the bathing water quality at Cold Knap for a number of years. Information is being shared to develop a combined approach to resolve issues impacting the water environment, such as rectifying misconnections which could be affecting the water quality of the streams flowing through Porthkerry Park, which outfall onto Bullcliff Rocks to the west of the bay.
Published by Natural Resources Wales under the Open Government Licence. The full profile carries more, including sections repeated for every beach that are not reproduced here.
Other swimming spots nearby
The closest bathing waters on the regulators’ lists, straight-line distance. Each has its own checks and its own verdict.
Check the official source
The regulator’s own page for this bathing water. If it disagrees with this one, believe theirs.
Cold Knap Barry's official page at Natural Resources Wales · See it on a map
This page is not official. It reads published data and presents it plainly; if a sign at the beach says otherwise, believe the sign.
If you get into trouble
This is the RNLI’s advice, not ours.
Float. Tilt your head back with your ears in the water. Relax and let your breathing settle. Move your hands and legs gently to stay level. Your legs may sink, and that is fine, everyone floats differently. The first shock of cold water passes in less than a minute, so do not try to swim straight away. Once it has passed, call for help or swim to safety.
Caught in a rip current? Do not swim against it, you will only tire yourself out. If you can stand, wade out of it. If the water is too deep to stand, swim parallel to the beach until you are clear of it, then head for shore. Raise your hand and shout for help.
Nobody publishes a rip current forecast for beaches in Britain or Ireland, so this site cannot show you one. The RNLI has one for its own lifeguards. The public does not. Look at the water before you get in, and look for a channel where the waves are not breaking.
In an emergency call 999 and ask for the Coastguard. In the Republic of Ireland call 112 or 999 and ask for the Coast Guard.
Where there are lifeguards, swim between the red and yellow flags. They put those flags where it is safest that day and move them as the sea changes. A red flag means do not go in, whatever this page says. An orange windsock means the wind is blowing offshore and inflatables should stay out of the water. Most places on this site have no lifeguard at all.
This advice is the RNLI’s. Their Float to Live pages are worth two minutes of anyone’s time.
Use this page elsewhere
One sheet of A4 with a QR code to this page, for a clubhouse, a campsite reception, a surf school or a harbour office. The address is printed underneath in words, so it still works for anybody who would rather not scan a code.
Print a sign for Cold Knap BarryOr put today’s verdict on your own site.
Put this beach on your own site
A small card showing today’s verdict for Cold Knap Barry, updating itself. Paste this where you want it to appear. It loads nothing of yours and sets no cookies, and it costs your visitors about ten kilobytes, most of it the readings themselves.
Click the box to select it all. There is also a feed for this beach, if you would rather be told than have to look.