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KHM Portsmouth / Using the port for recreation


Swimming across the Solent is not just another open water swim and should not be undertaken without considerable preparation.

Whilst not as difficult as swimming across the English Channel, the cross Solent swimmer has to cross a busy shipping lane, negotiate around ferries and hovercraft travelling to and from the Isle of Wight and avoid all the many pleasure boats using The Solent.

This Code of Conduct and associated guidelines was first drafted in 1990; in this latest edition advice has been added to aid would-be swimmers on routes to take and other navigational aspects. The Code has been prepared to assist charity and non-professional swimmers in their attempt to swim The Solent, principally on the Ryde – Gosport route. It should be read in conjunction with current Notices to Mariners and Standing Instructions applicable to the Ports of Portsmouth & Southampton. The “Port Marine Safety Code”, first published in March 2002 and updated in 2015, details formal procedures that have to be undertaken as part of a Port’s SMS (Safety Management System) before a person can engage in, for example, a cross Solent Swim. “As an integral part of the Port Marine safety Code, and in keeping with the SMS, Organisers of recreational events planned to take place within the Dockyard Port of Portsmouth or Port of Southampton have responsibilities for the safety of their event.” Notwithstanding, note that this requirement always applies, no matter where in The Solent the event is to take place.

These responsibilities include the undertaking of a Risk Assessment as part of the planning of the event. “Guidance Notes on Risk Assessments for Events in Harbour Authority Areas” is available from the Royal Yachting Association.

Additionally, a risk assessment template is available at the top of this page. Once complete, a copy of the Risk Assessment is to be posted / emailed to the King's Harbour Master, Portsmouth, HM Coastguard and ABP Southampton – address / email details as below.

Risk Assessment


Lots of people participating in a swim race in the sea with red swim caps on

Emergency and communication plans

An emergency plan and communications plan must be submitted as part of the Risk Assessment. The Risk Assessment with Normal Operating Procedure and its associated Emergency Action Plan must address the actions to be taken if swimmers are unable to complete the crossing and have to be removed from the water, and any other foreseeable incidents.

Cross-Solent swim

The cross-Solent swim must be planned and executed as a “group swim” and not as a “race”. Up to 24 swimmers may take part in a cross-Solent swim event, split into no more than two groups of not more than 12 swimmers/12 canoers/kayakers in a group. If splitting into two groups, then groups should be graded by swimming ability, with faster swimmers in one group and slower swimmers in the other.  The use of towed floats by swimmers is strongly recommended, as is the use of high visibility swim caps. Since the horizon of the swimmer is very limited the canoeist/kayaker should lead the swimmer and not the other way around. The spread of each group is to be no more than 100 metres from first to last swimmer. This is essential to ensure the group is readily identifiable by other water users and to ensure support boats can attend to all swimmers when required without excessive use of speed/generation of wash.

Commercial event

If the swim is run as a commercial event, then the coxswain of each boat must have a commercially endorsed boating qualification, and all craft operating on a commercial basis are to be commercially coded. If the swim is run as a non-commercial event, then the level of coxswain and crew qualifications, and type and suitability of craft proposed, are to be supplied so that KHM staff can make a full of assessment of the organisation and competence of personnel and suitability of equipment proposed. This will enable a full assessment of the level of safety of the proposed event. Whether commercial or non-commercial, all craft and coxswains are to have insurance to cover the event and proof of such cover should be provided. This may be covered by a single policy that covers the whole event.

Support and escort craft

Every swimmer is to have an individual safety escort craft; a kayak or a canoe. Fully inflatable vessels must not be used for this. It is recommended that the operator of the canoe or kayak hold a relevant qualification or to have experience of open water kayaking or canoeing. All support crew are to wear Personal Protective Equipment appropriate to their role, including use of personal floatation equipment (life jacket or buoyancy aid).

The support fleet, to include at least one powered vessel, shall be capable of recovering all the swimmers and kayakers/canoeists from the water, and either recovering the kayaks/canoes or taking them in tow. The considerations for support craft should include an ability to recover persons from the water, provide first aid treatment on board and provide shelter.

Recommendations for support crafts

  • It is strongly recommended that at least the lead support boat is fitted with AIS (Class A or B). If operating two groups, then an AIS capability in at least one boat in each group is recommended.
  • All safety vessels are to have a means of communicating with the shore and preferably other vessels. This must take the form of a Marine Band VHF radio which has at least the following channels fitted: 16, 67, 11, 12, 6, 10.
  • An international flag signal “Alpha” (“A”) must be displayed on all support vessels to indicate that there is a swimmer in the water. 

On the day

A swimmer in a yellow swim cap swims in the sea with kayakers in the background.

Details to relay

Having obtained a local weather forecast for the day and assessed the viability of the swim, the named authorities must be notified by phone of the organiser’s intentions for that day.

HM Coastguard, radio call sign “SOLENT COASTGUARD” should be notified on VHF channel 67, of the passage of the craft to the start point, intentions and the following:

  1. Name of the swim organiser, complete with telephone number.
  2. Number of swimmers, number of canoeists and total number of persons taking part in the event.
  3. Planned start and finish points complete with start time and estimated finish time.
  4. Method of communications being used complete with call signs/mobile telephone numbers etc.
  5. Name of a contact point ashore from which full details of the event could be obtained should communications with the group be lost.

Swim groups

If swimming in two groups, the groups should be time separated at the departure point; 10-15 minutes is suggested. Swims should be planned so that the two groups either cross the main shipping lane at the same time or are sufficiently separated so that large traffic can safely pass between the groups.

There should be no more than 12 swimmers in one escort group, with no more than two groups attempting the crossing at any one time. This group rating attempts to ensure that the swimmers remain grouped together whilst crossing the shipping channels.

Swim groups are to be carefully corralled to ensure they do not spread out. The maximum extent of the swimmers/kayakers should be no more than 100 metres from front to back, and the group is to be paced to the slowest swimmer in the group, with stops as required to allow slower swimmers to catch up when required.

During the period of the swim the international flag signal “A” shall be displayed on all support boats indicating a swimmer is in the water. This flag/board shall only be displayed when a swimmer is in the water.


The authorities are to be notified at the following positions:

  • When the swimmers start e.g. enter the water at Ryde
  • Just before the swimmer enters any main shipping channel e.g. at North Sturbridge
  • As the last swimmer leaves the main shipping channel
  • When the last swimmer is clear of the water and the event is finished.

Further communications should be made to HM Coastguard if a swimmer is removed from the water during the race and requires medical assistance. HM Coastguard should be immediately notified when the safety craft has cause for concern for the safety of those in his charge.

It should be noted that the authorities must also be notified if the swim is cancelled or postponed for whatever reason.

HM Coastguard, VTS Southampton and KHM should be notified when all safety launches and associated craft are safe and secure at their destination.

Find out more

Advice for swimmers

A lot of swimmer standing on shore prepare for a race

Swim routes

The shortest and easiest crossing in the Eastern Solent is from Fort Gilkicker at Gosport to Ryde Sands, a distance of 2 ½ miles. KHM will not support or approve any cross Solent swim from Southsea / Clarence Pier to the Isle of Wight, or vice versa, due to the complexities involved in crossing 2 shipping channels. In the Central Solent the tides are very complex and cross Solent swims in this area are very rarely undertaken. In the Western Solent the only practical cross Solent swim is from Hurst Castle to Colwell Bay on the island. Here the distance is only just over a mile but the tide is critical, with only about a 30 min stand when the current is sufficiently low to allow the swim. Consulting a reliable tidal stream atlas is a must if this swim is contemplated.

An individual in a red swim cap swims front crawl in dark water


A 3-4 mile sea swim is no mean achievement and for most swimmers demands some training. For stamina at least one 5 km swim in the pool should be accomplished as part of the preparations for the swim. The average sea temperature in The Solent in July and August is 18 deg C; ten degrees colder than most indoor swimming pools. To acclimatise to this and the choppier conditions of the sea, some sea swims of at least a mile should be undertaken. Except for a smear of Vaseline under the armpits to avoid chaffing, few swimmers these days bother to grease up for a Solent swim. Some do prefer to wear a body suit or even a lightweight wet suit but the choice is best made during the training swims
A Royal Navy sailor navigates a map aboard a Navy ship.


For all swims, reference to a chart of The Solent and to The Solent Tidal Stream Atlas is considered essential. For the Ryde to Fort Gilkicker swim, starting at Low Water, the stream runs eastwards in The Solent towards the Forts. To combat this, the start of the swim should be about 600 m east of Ryde Pier and begin with a heading to Stokes Bay using the church just west of Fort Gilkicker as an aiming point i.e. due North (true). If this heading is maintained, the course should take the swimmer close to the North Sturbridge Buoy, which is approximately 1 mile into the swim, and then to Fort Gilkicker.
A context image of a sunrise at sea


The wind and visibility are the main criteria governing whether a swim can take place although it might be unwise to set off if the forecast is for thunderstorms. The limiting wind condition depends on the ability of the swimmers and their experience. As a general rule the accepted limit is Force 4, which is the onset of white horses on the water. The direction of the wind also plays a part and the swim becomes more difficult if the winds, and the waves, are in the face of the swimmers. In terms of visibility, the swim is not to be started if land on the opposite side of the Solent cannot be seen or if the forecast is for deteriorating visibility. On no account, should a swim be attempted during the hours of darkness. As mentioned earlier the average sea temperature in The Solent is 18 deg C in July and August and this is when most swims are undertaken. In May and June the air temperature might be higher but the sea is still warming up. Not a problem for a short dip but might cause hypothermia on a long swim.

Notify the authorities

Before any swim can be undertaken, the authorities responsible for safety and which coordinate the passage of commercial vessels through the Solent need to be informed. It is incumbent on the swim organiser to notify, in writing, the above authorities at least 28 days ahead of the event, that a swim is planned.

KHM Portsmouth

Telephone: 0300 168 6043

Southampton Vessel Traffic Service

Telephone: 02380 608208

HM Coastguard – Solent

Telephone: 02392 552100

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