Llandegfedd Lake Wild Swimming

Llandegfedd is a working Dŵr Cymru reservoir at Coed y Paen, on the Torfaen–Monmouthshire border, NP4 0SY. Swim Wales SAFE Cymru accredited. You swim only in a designated zone, in a booked, lifeguard-assisted session. Visitor centre, café, changing with hot showers. You go because Pontypool actually has a ticketed reservoir swim, and because freelance swimming here is prohibited. Hidden machinery, cold, depth, poor phone signal. They are not being dramatic. If you want a marked course with a session time and a class pass, this is the one. If you want to pick a bay and get in, you will be turned away.

Getting in

Pre-book organised sessions only. There is no drop-in lap. A 10-session class pass is £75, which they call 25% off normal prices — so a single is about £10. Book the session and the class pass from the open-water swimming page. Club discounts exist in some cases; ask your club, not the gate.

Cold-water dipping is a separate product. Induction is £35: two hours, Institute for Outdoor Learning accredited, then a guided dip, plus five dips for the 2025–26 season. Visit Wales still describes that induction as the on-ramp, usually May–October, with dips four mornings a week through the year. Do not mix the dip ticket with the open-water swim in your head.

Group open-water swim is listed as adults only, around a 400m course. Pre-book groups at least two weeks out: 0330 0413 381 or llandegfeddenquiries@dwrcymru.com. Watersports (sail, SUP, canoe, kayak, windsurf) are March–October and also pre-booked. Dogs are not allowed in the water or in any craft.

The swim

A marked zone on a deep supply reservoir. Stay in it. Outside it there is automatic equipment under the surface. Visit Wales quotes supervised courses in the 100–300m range for confident swimmers; the group product is a 400m loop. Treat the booking page as the length you will actually get that day.

Visitor centre café with a balcony. Changing and hot showers in the activity centre. This is a proper Welsh Water site, not a lay-by. Same operator and same booked-session model as Lisvane & Llanishen in Cardiff.

They have also run a summer Open Water Splash — age 5+, 30 minutes, water 18°C or warmer, designated zone. The last dated splash block on the site was July–August 2025. Do not assume it is on in 2026 until the splash page says so. It is not the open-water swim.

Worth knowing

No freelance swimming. Booked supervised sessions only. The site can close at short notice: 14 August 2026 it shut for wildfire smoke. On 25 August 2026 the homepage was flagging a cancelled event and a Sluvad Road diversion. Check before you drive from Newport or Cardiff.

It is not a family beach and not a 750m training triangle. Lisvane & Llanishen is the sister listing — closer to Cardiff, designated inland bathing water, same rules about unauthorised swimming. Use both. Do not treat the rest of the reservoir as a wild-swim shoreline.