The shortest distance across the Channel is from Shakespeare Beach, Dover, to Cap Gris Nez (the headland halfway between Calais and Boulogne). This distance is 18.2 nautical miles which is approximately 21 land miles. There are 2,000 yards or 1852 meters to a nautical mile. Most of the England/France swims start from Shakespeare Beach between one hour before high water and one hour after high water, although the pilots do start at other times and places, depending on the tide, the weather conditions, and the swimmer’s ability. France/England swims (when these are permitted by the French authorities) usually start from Cap Gris Nez or its immediate vicinity. The traditional start time is about 3 to 4 hours before high water, although this can also vary considerably depending on the tide, weather, swimmer, and pilot. With the use of computerised plotting for course calculations and the modern electronics on the pilot boats, start times and places can be evaluated before the swimmer enters the water, and the best choice of the route is made.
The FLOOD TIDE flows from the South West from 1.5 hours before HIGH WATER to 4 hours after HIGH WATER DOVER. The EBB TIDE flows from the North East from 4.5 hours after HIGH WATER to 2 hours before HIGH WATER DOVER. As the tidal cycle is a little over 12 hours from one high water to the next, the times of high water change every day getting later as the days progress.
Because of this movement of water from one place to another, the Dover Straits are prone to strong tidal flows, and a large rise and fall in water between high and low tide. To complicate things a little more, the position of the moon relative to the earth and the sun affects the gravitational pull that is moving the water. When the sun, moon, and earth are in line we have maximum tides known as SPRING TIDES. This is every 14 days on the new moon or the full moon. When the moon is at 90° to the earth, we have minimum tides known as NEAP TIDES. This is every 14 days when the moon is in its first and third quarter. Thus we have 14-day cycles with the tides going from Springs to Neaps and back to Springs. From tidal atlases and nautical almanacs, we find that at Dover: Mean High Water Springs is 6.7 metres. Mean High Water Neaps is 5.3 metres. For Channel swimming – Spring tides are 6 metres or more and Neap tides are 6 metres or less. Most swims take place on the Neap tides. These are the slacker tides and show as a more direct line on the chart. The lower the tide, the longer the period of slack water when the tide turns, and the slower the tidal flow. Approximately 6 am and 6 pm (GMT).
This is between 57°F and 64.5°F (14°C to 18°C). The temperature is around 57 to 60°F at the end of June beginning of July, then rises slowly to 64/65°F by the end of August, then it usually drops by a couple of degrees before the beginning of October. There are however exceptional years like 1995 when the water temperature reaches 67°F (19°C).
Air temperature and chill factor
This varies considerably depending on the weather and the hours of daylight. The longest day is about the 21st of June, giving daylight from about 0330 to 2200 hours. This decreases to 0600 to 1900 hours by the end of September. Body heat is lost from the parts of the swimmer exposed to the air (head and shoulders, etc.). The air temperature is higher during daylight hours, therefore the longer the day, the greater the period of higher air temperature, and the smaller the loss of body heat.
The English Channel is one of the busiest shipping lanes in the world, with approximately 600 vessels moving up and down them every day, and ferries, hovercraft, seacats, and jetfoils crossing between England and France at very regular intervals. Because of this international shipping lanes have been agreed upon and their areas marked on the charts. On the English side, we have the South West Lane which is for vessels traveling down Channel to the Atlantic. On the French side, we have the North East Lane for vessels that are traveling up the North Sea areas. Crossing from Dover there is the English inshore traffic zone which is about 5 nautical miles wide, followed by the South West Lane which is approximately 4 nautical miles wide. In the middle is an area known as the Separation Zone which is one nautical mile wide. Then there is the North East Lane which is approximately 5 nautical miles wide, followed by the French inshore traffic zone which is 3 nautical miles+ (depending on where you are) to the French beaches. The English Coastguard, stationed at Langdon Battery Dover, and the French Coastguard, stationed at Cap Gris Nez, keep radar and VHF watch on the whole of this area liaising with the vessels using the Channel. They broadcast navigational bulletins every half hour and log vessels using the lanes to coordinate the movements and monitor safety. Channel swims differ from other swims of this distance by their complexity and the local environment. This is why it is one of the ultimate challenges.
Just over 800 of over 4,370 attempts have been successful since the formation of the Channel Swimming Association in 1927.
Captain Mathew Webb was the first person to swim the English Channel. He accomplished this feat on August 23, 1875, on his second attempt, with a time of 21 hours and 40 minutes, swimming from England to France. Not only was the swim significant as the first successful swim, but his course was altered by the tides, making the ordinarily 20-mile swim considerably longer.
As shown on the diagram of his route below, Webb was pushed west, then east, followed by another larger western push, and finally by a huge eastern push, ending with a landing in Calais. Most English Channel swimmers follow a variation of this crossing. Missing the coast is the largest single reason for a swimmer to quit the attempt to conquer the Channel. For most swimmers, the thought of swimming another six hours while waiting for the tide to change is too demoralizing, painful, and cold to endure.
COURSE OF THE SWIM
The more the pilot knows about the tides, weather and the swimmer’s ability, the more accurately can he plan his intended course. Pilots draw on their experience and local knowledge to forecast the best departure point and time for their swimmer. The Skipper’s own observations of the actual conditions on the day, the regular advice supplied by the Coastguards and the position fixes given by modern navigational instruments all combine to permit fine course adjustments to be made en route, to the swimmers best advantage.
The tidal flow is almost parallel to the coast and the swimmer is swimming at approximately 90º to the coast. Fortunately, the tides flow first one way and then the other way, and their effect is largely evened out over a 12-hour period. Even though the swimmer may hold a steady Heading through the water towards his destination, his “Ground-Track” will be curved. So there is little to gain -and much to lose – by doing battle with the Tides trying to achieve a direct Ground Track! There are places during the crossing where one can get a little help from the tide, but there are also areas where progress will be hindered. The idea is to get a balance between the two.
The Pilot’s job is to guide the swimmer so that he can be in the right place at the right time, in order that the currents give the maximum assistance – and the least hindrance. To achieve this, he will need to know, in advance, the swimmer’s sustainable swim rate over the period of the swim. He needs to time your approach to the Coast so that the tides do not work against the swimmer just when he is most tired. N.B. The Coastline of France is not parallel to England. It ‘drops away” on either side of Cap Griz Nez.
Adequate and appropriate nourishment is vital to the swimmer’s success, but has to be done briefly: an over-run of the half-hourly feed time by even as little a 1 minute every time could make the difference between landing with the tide or of having to swim on for several more hours!
The English Channel is one of the busiest shipping zones in the world, with approximately 500 vessel movements every day…..and there are ferries, hovercraft, sea cats, and jetfoils crossing between England and France at very regular intervals. Because of this, International Shipping Lanes have been agreed and their areas marked on the charts. On the English side, we have the ‘South West Lane’ which is for vessels traveling down the Channel to the Atlantic. On the French side, we have the ‘North East Lane’ for vessels, which are traveling, up to the North Sea areas.
The English Coastguards, stationed at Langdon Battery Dover, and the French Coastguards, stationed at C.R.O.S.S. Cap Gris Nez, keep radar and VHF watch on the whole area…..liaising with the vessels using the Channel. They broadcast navigational bulletins every half hour and log vessels using the lanes to coordinate ship movement and to monitor safety. In these announcements, they warn shipping of the presence of Cross Channel Swimmers and give the latest known positions of the Escort Vessels.
Channel Swims differ from other swims of this distance by their complexity and the local environment. There are hazards such as jellyfish, seaweed, flotsam and jetsam. Most particularly, the swimmer has to navigate safely across the Commercial Shipping Lanes – and give way to most other vessels in the Strait.
Swimming the distance of approximately 35.8 km each way is only part of the challenge. Other factors which have to be encountered, making it the “Everest” of swimming, include:
- cold water temperature
- divergent currents
- water pollution
- waiting time
- sea conditions on the day
- sea sickness
In addition, there is an element of luck involved in getting everything to fall right on the day.This is why it is one of the ultimate challenges….the ‘Benchmark’ of Marathon Swimming.
Waiting for the conditions to materialize One cannot plan the exact day on which you are going to swim. Whilst you may have booked your 1 week window within which you hope to swim, weather conditions from day to day may delay or even prevent a swim indefinitely – many swimmers have had to pack up and return home without even having had a chance to swim. The unpredictable English weather changes from being sunny and calm, to stormy, within a few hours. This waiting game and uncertainty play havoc with your mind to such an extent that when you do climb into the water all your mental preparation and ‘psyching’ oneself up, has been long forgotten and is wasted. On top of that, being a harbour port and a military base, Dover is not the most pleasurable place to spend your days waiting. A further aspect is the relating to training when waiting. Do you carry on training while waiting or do you rest in case your swim is the next day?