Swim coach Alice Goodridge explains how to stay safe while swimming near waterfalls and shares some of her favourite spots in the UK
Waterfalls are a great reminder of the immense power of water to shape the landscape. They are often found in rocky upland river catchments that respond rapidly to rainfall, leading to high flow rates at peak times. Trickling falls with calm pools can quickly turn into raging cascades with deadly undercurrents.
Water falling from a height presents a range of significant dangers to swimmers. The power of the water varies with the flow rate and the height of a waterfall affects its strength. It is important to never swim close to the churning area of water directly below a waterfall with a deep plunge pool.
When water drops over an obstruction (ledge or rock) into deeper water below, the downwards force causes water to be drawn back round on top of itself, creating a circulation motion known as a hydraulic. Hydraulics can flow in two directions at once, creating opposing circular currents, meaning that you can easily become trapped in a loop due to the return current, making it very difficult to escape.
In addition, water falling from a height will always be highly aerated, bringing its own dangers. The bubbling, foaming white water at the base of a waterfall is much less dense than the surrounding water due to the amount of air mixed in with it. This can have a big impact on your buoyancy. You will be affected by gravity much more meaning that your ability to float will be greatly reduced and you are much more likely to sink.
When swimming in a waterfall plunge pool you are likely to feel the pull of the circulating currents before you are in danger of being sucked into the aerated hydraulics beneath the fall. If you do find yourself pulled under by the circulating water, it will feel like being caught in the undertow of a large wave and tumbled in a washing machine. The best thing to do in this situation is to keep calm and dive to the bottom of the hydraulic pool and take the deepest current which will then lead to the escape flow.
Five favourite waterfall pools to take a dip in
Low Force – County Durham
Beautifully pretty and quiet compared to its larger sibling, High Force, Low Force features a range of pools and hidden spots tucked in between rocks. Be careful of the flow as the force over the waterfall can be ferocious.
Black Moss Pot – Lake District
A popular spot for wild swimming, Black Moss is a deep pot with a 6m cliff for jumping where the water is several metres deep. Near the main waterfall is a spacious pool for swimming.
St Nectan's Kieve – Cornwall
A tall waterfall which drops into a small, 1.5m deep plunge pool. Bear in mind, during periods of low rainfall, the pool can often be too shallow for swimming.
Kidson Froce – Yorkshire Dales
Two waterfalls – one 5m high, the other 12m – in the River Swale just below the village of Keld. Great for plunging and jumping.
Fairy Pools – Isle of Skye
Embued with legend and fairy tales, the famous ‘Allt Coir a Mhadaidh’ pools are crystal clear. Cold year-round, they are great for cliff jumping.
As ever, take care when jumping into water. Never jump or dive in without checking the depth first, even if you visit the spot regularly. Depths can vary depending on rainfall and new underwater obstructions could also be present.
A recent adventure chasing waterfalls
Packing up our overnight camp by the ruins of Bynack Lodge, I double-check our route before setting off alongside the Geldie Burn, towards Glen Feshie. Marked on the map, about 10km from our start point, is a small footbridge across the River Eidart. My eyes are immediately drawn to the magical worda printed next to the bridge - Waterfall!
As we near the falls I begin to hear the roar of the water tumbling over the steep rocks into the bubbling plunge pool below. The surface of the water is restless and choppy. Stepping into the black, churning water, it feels like I am swimming in a giant witches cauldron.
Looking up I am hypnotised by the endless flowing water.
I only allow myself a quick dip in the pool this time, sticking by the edge and being careful not to swim too close to the heavy flow of the main cascade. Getting out I feel revived, refreshed and completely alive. A perfect waterfall dip!