Where Did You Swim Today?

It surprises me that time and again I see comments on swimming forums along the lines of: “we went for our swim but the tide was out”, “the river was in flood” and of course “we went looking for this swimming place but couldn’t find it.”  Some of these are merely an inconvenience, but on other occasions having made the effort to reach a place it may become a case of ‘swim and be damned’ even if conditions are dubious and swimming best avoided.

Consequently it would perhaps be helpful then to highlight some of the prolific on-line resources that can be accessed before ever setting foot outside the door.  Web site addresses are given at the end and were current and working when this was published.

Where am I going today?

For South Devon I would like to claim that my Google Map Click Here  is the definitive outdoor swimming resource.  It’s not of course as it is not possible to regularly keep up with the 180 places I have listed.   However, when planning out your trip there are many map resources some more helpful than others.

My personal favourite is ‘Streetmap’.  This is less a route planner than some of the others but gives greater detail on the chosen location and offers a very comprehensive ‘smart search’ for town or village names etc. but also ‘features’.  If, for example, you search for Red Lake then one of the four results and the only one in Devon is a favourite swimming place out in the middle of Dartmoor.

Wild Swimming
Wild Swimming

The standard view is 1:50000, but the stepped scales include the 1:25000 Ordnance Survey mapping, with details of parking places, footpaths, public access land, etc. and is perhaps the most useful level of detail.

Maps are of course all very well but they don’t show you for instance if the car park will hold 5 cars or 50.  As an example the National Trust car park at Prawle Point is shown on the OS Map and from that information alone you will know that a parking fee is due from non-members.  This is where ‘Google Earth’ comes in to its own, which is free from Google and provides the clearest and most up-to-date views.  Zoomed in to a scale that shows individual cars it is a little blurry, but it is simple enough to pick out footpaths through fields, roadside lay-bys that will take a single car and for swimmers both the place they plan to swim and importantly access points to the water.  The current view shows 7 cars in the car park at Prawle Point and clearly from that it is apparent it will take about 15 at the very most.  There is no other parking for some distance and putting all that together it is simple enough to work out that arriving early is probably advisable.

Panning and tilting the Google Earth view is also a good way to visualise the profile of the location, for example, how steep the cliffs are.  Using the ‘Ruler’ utility on the task bar allows you to make ‘as the crow flies’ measurements or plot and save a route with waypoints and of course you can place markers for your favourite (swimming) places with appropriate icons.

The above are all very well but they won’t give you a clear picture of the actual location.  Simply searching the likes of Google for the location and selecting ‘images’ will very likely provide you with an abundance of photographs.  For example searching for Sharrah Pool on Google provides hundreds of hits, but these are not always 100% reliable.  As I am looking at it today the 8th image is not Sharrah Pool (it’s 3 skinny dippers at Wellsfoot) and even reputable resources like wildswim.com get it wrong (FYI that’s Bellpool) either because the individual image is wrongly tagged or because it has been taken for example from a blog post about visiting Sharrah Pool and the picture has been pulled out because of the tags associated with the blog and not the individual image.  However, some people do post pictures blissfully unaware of where they were when they took it.

There are also other swimming themed maps, which may give directions, images and safety information.  However, most of these rely on input from individuals that is usually not peer reviewed.  Using Sharrah Pool again as an example you could have a description that says ‘a 2 mile, 40 minute walk, from the car park through woodland along a clear path to the 100m long, deep pool with places to jump in’.  As it stands that is correct, it is exactly 2 miles and the path is reasonable, but if you were not so agile on your feet or were visually impaired it would be challenging (and I have lost count of the number of people I have had to give directions to because they have turned back or otherwise assumed they have lost the way).  The pool is often quoted as ‘100m’, but only 70m is deep enough to swim.  There are places to jump in, but they are not the places that appear immediately obvious and there are a lot of underwater rocks that cannot be seen.  And the river is prone to flash flooding in this deeply cut valley that takes run off from a large area of very wet moorland.  Simply put, one person’s idyllic swim could very easily be another person’s nightmare if the information is taken at face value without due consideration for changing weather and seasons.

That leads very neatly to:  What is it like today?

How, you may be thinking, is it possible to find out what the water conditions are right now without going and taking a look?  Once again the internet is your friend.

Begin with a weather forecast.  There are numerous resources but for simplicity I like the BBC.  Some information is immediately obvious: is the sun shining?  Then take sunscreen.  Is it raining or going to rain?  Then take a coat but also use common sense in so much as, if it is raining heavily now will the river be in flood when the sun comes out this afternoon?

Other information is available and can be used to make informed choices.  Most forecasts show a wind speed and direction which is particularly relevant at the coast.  If there is a strong onshore wind the chances are that the sea will be rough.  However, it may be that a short distance away, on the other side of a headland for example, the wind is conversely blowing offshore and the beach is in the lee of high cliffs.  The sea is therefore likely to be sheltered and calm, but that strong wind is blowing offshore and if you go out of the shelter of the headland you may well find getting back in to the beach is a challenge.

‘Magicseaweed’ provides possibly the easiest means to access actual wave height measurements in real time from a network of buoys at sea.  You don’t need to guess how rough the water is, you can find out right now.

Before considering sources of information on tides it would be as well to outline why there are tides in the first place.  The short answer is because the gravity of the sun and moon pull the water on the surface of the Earth towards them making the water bulge, but in a balancing act that stops the whole affair spinning hopelessly out of control the bulge on one side of the Earth is matched by a second on the opposite side of the planet.  The Earth rotates every 24 hours and because the bulges are held in place by the forces of gravity the apparent effect is that 2 waves sweep around the Earth 12 hours apart giving 2 high tides at any point every day (and 2 low tides to maintain the balance).  From this simplistic model it would be reasonable to assume that each day the high and low tides will happen at the same time of day and I know people who have made that assumption only to find there was no water at the beach.

The situation is however made more complicated by the fact that the Earth orbits the Sun every year and the Moon orbits the Earth every 29 days.  Consequently the time of high tide advances by about 6 hours every 7 days.  For example, if at a beach high tide is at 12 noon on day 1, 7 days later it will be low tide at noon, 7 days later high tide again (except the 29 day lunar cycle does not divide equally by 7 days, nor does the Earth orbit the Sun exactly every 365 days so the times slowly creep).

Finally, if the Sun and the Moon are on the same side of the Earth or oppose each other their gravities work together to produce higher than average ‘spring’ tides, but if they are at 90 degrees to each other in the sky the gravities work against each other to give smaller than average ‘neap’ tides.

There are again many tidal resources on-line but UK Admiralty ‘EasyTide’ has information for sea ports all around the world, an easy map based locality finder and free predictions for 7 days.  There is also a simple adjustment for British Summer Time.  The graphical interface also shows the spring and neap tides from which you can deduce how fast the tide will be moving as generally a bigger tide = faster flow.

From the point of view of the observer standing on a beach it would appear that a tide comes in and goes out, rises and falls.  However thinking about a bulge of water that creates a wave moving around the world analogy it should be apparent that as the ground seemingly approaches the bulge it would be as though the water is moving towards you and once past the bulge the water is moving away.  If the beach looks east-west then the water will apparently come in and go out, but looking north-south the water will apparently move sideways and then reverse.  A sailing almanac has port-by-port charts showing current flow direction throughout a full day along with flow speeds as the tide rises and falls.

‘Visit My Harbour’ provides larger scale overviews and taking Torbay as an example it is easy to see that as a general principal 3 hours either side of high tide the current flows eastward (northward in the confines of Torbay due to the shape of the coast) but westward (southward in the bay) 3 hours either side of low tide.  The flow is not generally great but can become locally magnified due to the shape of the seabed and coastline.  Consequently if swimming off a beach in Torbay currents are not a major worry, but Thatcher Rock is only a few 100m off shore and it would be tempting to swim out to it, after all, how could you go wrong?  Except that when the current flows it becomes confined in the channel and will rush by at 8 to 10 Knots (roughly mph) and becomes a churning mess and if you try to swim in that then you might get to France but you are unlikely to get to Thatcher Rock.

For rivers a similar resource is available in England through the Environment Agency (Wales, Scotland and Northern Ireland are covered by independent resources).  The EA maintains an extensive network of river level monitoring stations and the data is displayed graphically on-line sometimes as an almost live feed, though a 3 hour lag is often the case.  The information shows the normal river level and also the changes to the level over the preceding 5 days.  Crucially from the pattern of data it is easy to see if the river level is rising upstream and thereby work out if it is likely to be coming on to flood downstream where you intend to swim.

There is however no substitute for actually being able to see right here and now what conditions are like at the beach or in the river.  Fortunately there are web cams at many locations though feeds are often lost for days or weeks.  Magicseaweed on-line offers a drop down menu for coastal web cams though it is not exhaustive and Farson Digital Water Cams covers many inland waters.  So for example as I write this I can see that the water in the River Dart at Buckfastleigh has dropped back from the flood conditions of the weekend but that the surf at Bantham means it would not be favourable for a swim around Burgh Island any time soon.

All of this may seem out of proportion just to go swimming but it can make all the difference.  For instance early on Sunday morning the sky was clear, there was a beautiful sunrise and no wind at home with my choices being the River Dart or Teignmouth Beach.  A few moments researching conditions whilst drinking a coffee told me the river level was falling and was nearly back to ‘normal’ and that there would be no wind.  Whilst those were ideal swimming conditions I would rather have gone to Teignmouth.  Clearly however, even though the wind had dropped the surf kicked up at Teignmouth by the storm overnight on Friday had not lessened.  Consequently I had my pleasant if rather dull river swim and later saw comments by someone who had intended to swim at Teignmouth and got there only to find the sea unswimmable.  “Smug mode.”

All in all taking a look at some of these resources whilst planning a swim, understanding the implications and finally checking other details just before setting off can make the difference between a great swim and a huge disappointment.

Resources:  (most can be found by searching on-line for the web site name rather then copying the URL)

Streetmap:  http://www.streetmap.co.uk/

Google Earth:  download the application from the Google home page.

Wild Swim Map:  http://wildswim.com/

Wild Swimming Map UK:  http://www.wildswimming.co.uk/wild-swim-map-uk/?multi_region=wild-swim-map-uk

Wild Swimming Devon:  https://www.google.com/maps/d/viewer?hl=en&mid=11aPwVQ8Yn6pQQ23rUst1DiIUyuc

BBC Weather:  http://www.bbc.co.uk/weather/

Magicseaweed:  http://magicseaweed.com/UK-Ireland-Wave-Buoys/1/

Admiralty EasyTide:  http://www.ukho.gov.uk/Easytide/easytide/SelectPort.aspx

Visit My Harbour Tidal Flow Charts:  http://www.visitmyharbour.com/articles/category/842/tidal-streams/

Environment Agency England:  https://flood-warning-information.service.gov.uk/river-and-sea-levels

Farson Digital Water Cams:  http://www.farsondigitalwatercams.com/

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