About Llyn Padarn

Llyn Padarn is a glacially formed lake. It is one of the largest natural lakes in Wales and is approximately 2 miles (3.2 km) long and at its deepest point is 94 feet (29 m) deep.

Llyn Padarn is home to a population of Arctic charr, a rare fish that has become isolated in some lakes after the last Ice Age ended. The Welsh populations of charr are a distinct race and the population at Padarn is genetically different from those in Llyn Cwellyn and Llyn Bodlyn. Spawning in Llyn Padarn occurs locally in shallow, marginal waters, notably along Afon y Bala.

Llyn Padarn is home to two notable species of aquatic plant, floating water-plantain (Luronium natans) and small quillwort (Isoetes echinospora).

Otters and small numbers of wildfowl frequent the lake.

At its outflow from Llyn Padarn, the Afon Rhythallt, is one of the most important spawning sites for salmon and sea- trout in north Gwynedd.

Llyn Padarn is of national geological importance because the 600m-long section located alongside the Llanberis Lake Railway exposes a thick sequence of volcanic and sedimentary rocks of Cambrian age.

Loving OUR Lake

Whether you have a business on the shores of the lake, enjoy swimming in the lagoons, catching fish, walking your dog, or you simply drive past it everyday, all of us who live, work or holiday in the Llanberis valley have a link to Llyn Padarn. To help protect the lake for the future, we can all make some simple changes to our day-to-day activities that will reduce the input of harmful nutrients.

Septic Tank Guide & Logbook

Download a free pdf: 'Looking After your septic tank: a guide and logbook for householders'.

Don’t Ignore It, Report It!

To report an environmental incident please call NRW incident hotline on 0300 065 3000 (24 hours a day). NRW website has further details on what kind of incidents to report and you can report online at: Report a problem

See It. Report It. Stop It

If you see sewage pollution please call the Dŵr Cymru hotline as soon as possible on 0800 085 3968. The contact centre is open 24 hours a day, every day of the year. Calls are FREE from a BT landline. You can also report pollution online at: Report an issue

Loving our Lake Pledge

We are encouraging local businesses to take the loving our lake pledge to commit to ensuring that their activities do not knowingly harm the lake. Click here to see who has taken the pledge.