Shom L Nautical Chart – English Channel

Introduction

The Shom L nautical chart of the English Channel is a folded paper nautical chart designed for route planning and navigation in the English Channel, between the French and English coasts and around the main ports and maritime areas of this particularly busy region. Published by the French Hydrographic and Oceanographic Service, Shom charts provide structured nautical information on coastlines, seabed characteristics, hazards, aids to navigation and the main features relevant to navigation.

The English Channel is a complex maritime area. It connects the North Sea with the Atlantic Ocean and has a high density of commercial shipping, recreational sailing, fishing and cross-Channel traffic. Tidal currents, significant tidal ranges, banks, shoals, rocks, channels, traffic separation schemes and numerous ports make accurate charting essential for navigation in this area.

The Shom L English Channel range covers numerous sectors, from northern Brittany and the Cotentin Peninsula to the Strait of Dover, including the French coastline and the British waters directly involved in Channel crossings.

A nautical chart designed for navigation in the English Channel

The English Channel has specific characteristics that distinguish it from other French navigation areas. Strong tidal currents in some areas, the proximity of the two coastlines, heavy maritime traffic and the presence of numerous islands and archipelagos require careful reading of the chart.

Shom L charts can be used to prepare different types of navigation:

• coastal navigation along the French coast;

• passages between France and England;

• English Channel crossings;

• navigation around the Channel Islands;

• sailing in northern Brittany and the Cotentin Peninsula;

• navigation in the Dover Strait area;

• harbour approach planning;

• cruising and recreational sailing;

• preparation of offshore routes close to the coast.

The Shom catalogue includes L charts covering western areas of the English Channel, approaches to Cherbourg, the Chausey Islands and Jersey, the Bay of Seine, the Strait of Dover and various coastal and harbour areas.

Main areas covered

The English Channel stretches between northern Brittany, Normandy and the southern coast of England. The Shom L English Channel category includes charts dedicated to numerous geographical sectors.

To the west, chart coverage includes areas around Ouessant, Île de Batz, the Roches de Portsall, Roches Douvres and the northern Brittany coast. Further east, charts cover the approaches to the Cotentin Peninsula, Cherbourg, Barfleur, the Bay of Seine, the Normandy coast and the Strait of Dover.

The Channel Islands are also an important area. Jersey, Guernsey, the Casquets, the Minquiers and Chausey are located in an environment characterised by significant tidal currents and tidal effects.

In the Strait of Dover, navigation is also subject to a high concentration of commercial shipping. Charts covering Boulogne-sur-Mer, Calais, Dunkirk, Dover and the English coast help prepare routes through this strategically important maritime area.

English Channel ports

Shom L English Channel charting covers numerous ports and sheltered areas distributed along both sides of the Channel.

On the French side, these include:

• Brest and its approaches;

• Saint-Brieuc;

• Saint-Malo;

• Granville;

• Cherbourg-en-Cotentin;

• Barfleur;

• Dieppe;

• Fécamp;

• Le Havre;

• Ouistreham;

• Port-en-Bessin;

• Cherbourg;

• Boulogne-sur-Mer;

• Calais;

• Dunkirk.

On the British side, routes may involve Plymouth, Dartmouth, Weymouth, Portsmouth, Southampton, Poole, Brighton, Dover, Ramsgate and Folkestone.

These ports are not all represented on a single chart. They illustrate the geographical extent of the area and the diversity of routes that can be prepared using Shom charts for the English Channel.

A region strongly influenced by tides and currents

The English Channel is one of the French maritime areas where an understanding of tides plays a particularly important role.

Water levels and currents can vary significantly depending on geographical position, tidal phase and weather conditions. In certain areas, particularly around the Cotentin Peninsula, the Channel Islands, northern Brittany and the Strait of Dover, currents can become a decisive factor when planning a route.

The nautical chart makes it possible to identify the configuration of the seabed, channels, banks, shoals, islands and passages. It should be used together with appropriate tidal information and other nautical data.

For an English Channel crossing, route planning therefore does not simply involve drawing a straight line between two ports. The route, currents, traffic, regulated areas, traffic separation schemes and local conditions all need to be taken into account.

What does a Shom L nautical chart contain?

A Shom L chart presents the nautical information required to understand the represented area. Depending on the scale and sector, it may show:

• soundings and depths;

• depth contours;

• shoals;

• rocks;

• wrecks;

• landmarks;

• lights and their characteristics;

• buoys and other aids to navigation;

• channels;

• ports;

• anchorages;

• regulated areas;

• certain maritime installations and infrastructures;

• traffic separation schemes;

• various navigation reference points.

In the English Channel, this information is particularly important because of the density of maritime traffic and the proximity of the different shipping routes.

The Shom L format: a practical folded chart for use on board

The letter L identifies a particular presentation of Shom nautical charts. Unlike Shom C charts, which are generally supplied flat and rolled, Shom L charts are folded.

The chart is generally folded to approximately A4 size and unfolds to a surface close to A0. This format makes it possible to retain a large cartographic surface while facilitating storage and transport.

It is particularly suitable for sailors who want to keep paper charts that can be easily filed with their nautical documentation.

The folded format is also convenient for preparing a passage, studying an area ashore and then storing the chart on board without having to continually handle a large rolled chart.

Differences between Shom C, L, G, Z and Raster charts

Shom C and Shom L charts have essentially the same general cartographic purpose, but their physical presentation differs. Shom C charts are designed to be stored flat or rolled, whereas Shom L charts are folded.

Shom G charts provide additional information concerning seabed characteristics and sediment distribution. They can be particularly useful for certain professional activities, including fishing.

Shom Z charts retain the nautical information of a standard chart while adding an overlay dedicated to exercise and firing areas.

Shom Raster charts are digital versions. Shom raster nautical charts are distributed in GeoTIFF format, with a resolution of 300 dpi and WGS 84 georeferencing associated with the Mercator projection. Shom distinguishes several scale categories, including general charts, ocean and passage charts, coastal charts, ports and anchorages.

Choosing the correct scale for the English Channel

Scale is an essential criterion when selecting a nautical chart for the English Channel.

A small-scale chart provides a broader view of a sector and may be suitable for passage planning or a general route overview. A large-scale chart covers a more restricted area but provides more detailed information.

For example, for a passage between Cherbourg and Portsmouth, the chart should provide sufficient coverage of both approaches and the intervening maritime area. For entering the ports of Dieppe, Le Havre, Cherbourg or Boulogne-sur-Mer, a larger-scale chart is required to provide detailed information on the approaches.

The Shom L English Channel category includes references at different scales and for different areas. Some charts cover a substantial portion of the coastline, while others are dedicated to a specific port or more limited coastal area.

Examples of Shom L English Channel charts

The range includes references such as:

• 6680L: from Île d’Ouessant to Île de Batz;

• 6930L: from the Roches de Portsall to the Roches Douvres plateau;

• 6940L: from Start Point to The Needles, including the Casquets traffic separation scheme;

• 7161L: from the Chausey Islands to Jersey, including the Minquiers plateau;

• 7207L: ports of Fécamp and Le Tréport;

• 7214L: from Dunkirk to Oostende;

• 7232L: from Nez de Jobourg to Pointe de Nacqueville;

• 7247L: approaches to Boulogne-sur-Mer;

• 7258L: approaches to Calais;

• 7312L: from the Casquets to the Strait of Dover;

• 7323L: Strait of Dover, from Boulogne-sur-Mer to Calais and from Dungeness to Dover;

• 7341L: approaches to Granville;

• 7417L: approaches to Fécamp and Dieppe;

• 7418L: approaches to Le Havre and Antifer, Seine estuary;

• 7420L: ports in the Bay of Seine;

• 7422L: from Pointe de Barfleur to Pointe de la Percée, including the Saint-Marcouf Islands;

• 7424L: Strait of Dover, from Calais to Dunkirk and from Dover to North Foreland.

These examples show that the Shom L English Channel range does not correspond to a single chart covering the entire area. It is a collection of complementary references, each designed for a specific geographical area and scale.

A useful chart for passage planning

The English Channel is crossed every day by merchant ships, ferries, cargo vessels, fishing vessels and recreational craft. Planning a Channel crossing must therefore take shipping patterns and traffic separation schemes into account where applicable.

A paper chart allows sailors to visualise the French and English coasts, islands, hazards, shipping routes and major landmarks simultaneously.

For recreational sailors, it can also be used to prepare passages between Saint-Malo and Jersey, Cherbourg and the Channel Islands, Dieppe and the English coast, or Calais and Dover.

Charting suitable for different types of sailors

Shom L English Channel charts can meet the needs of many different users:

• sailing yacht crews;

• motorboat crews;

• coastal navigators;

• offshore sailors;

• delivery crews;

• professional and recreational fishermen;

• maritime schools and training centres;

• maritime professionals.

The paper chart can be used as part of route preparation and can also complement a GPS, chartplotter or electronic navigation system.

It provides an overall representation of the area and allows the different stages of a passage to be prepared before departure.

Conclusion

The Shom L English Channel nautical chart range provides nautical documentation suited to navigation in one of Europe's busiest maritime areas. From northern Brittany to the Strait of Dover, through the Cotentin Peninsula, Bay of Seine and Channel Islands, the English Channel features a wide variety of coastlines, ports, channels, banks and navigation areas.

The folded Shom L format combines a large cartographic surface with convenient storage. However, the reference should always be selected according to the intended navigation area, route and required scale.

Whether preparing an English Channel crossing, sailing around Jersey or Guernsey, heading for Cherbourg, Saint-Malo, Dieppe, Le Havre, Calais or Dunkirk, or planning a route towards the English coast, several references may be required to ensure consistent chart coverage.

The Shom C, L, G, Z and Raster ranges also address different cartographic requirements: rolled paper charts, folded paper charts, seabed information, identification of exercise and firing areas, or georeferenced digital chart images.

FAQ – Shom L English Channel nautical charts

What is a Shom L English Channel nautical chart?

A Shom L English Channel chart is a folded paper nautical chart covering a specific area of the English Channel. It represents information relevant to navigation, including depths, hazards, aids to navigation, ports, channels and special areas.

What is the difference between a Shom C and a Shom L chart?

The main difference is the format. A Shom C chart is generally supplied flat and rolled, whereas a Shom L chart is folded to approximately A4 size and unfolds to a surface close to A0.

Which Shom L chart should be chosen for navigation in the English Channel?

The choice depends on the precise area and required scale. A chart intended for Cherbourg, Jersey, Dieppe, Le Havre, Calais or Dunkirk will not necessarily cover the same areas.

Which areas of the English Channel are covered by Shom L charts?

The range includes northern Brittany, the Cotentin Peninsula, the Channel Islands, the Bay of Seine, the Normandy coast and the Strait of Dover, as well as certain areas off the British coast.

Which islands are covered by Shom L English Channel charts?

Depending on the reference, charts may cover Ouessant, Île de Batz, Chausey, Jersey, Guernsey, the Minquiers, the Casquets, the Saint-Marcouf Islands and other islands and archipelagos close to the French or British coasts.

Which ports may be covered by a Shom L English Channel chart?

Depending on the reference, chart coverage may include Saint-Malo, Granville, Cherbourg, Dieppe, Fécamp, Le Havre, Ouistreham, Boulogne-sur-Mer, Calais and Dunkirk, as well as British ports such as Portsmouth, Southampton or Dover.

Why are tides important in the English Channel?

The English Channel is subject to significant changes in water level and tidal currents. These phenomena can influence route planning, harbour approaches and the passage through certain areas. The chart should be used together with appropriate tidal information and nautical data.

What scale should be chosen for an English Channel crossing?

A scale suitable for a crossing provides a sufficiently broad view of the route. Larger-scale charts may then be required for harbour approaches, channels, anchorages and areas requiring more detailed navigation.

What is a Shom G chart used for?

A Shom G chart is a sedimentological chart. It includes nautical chart information while providing additional indications concerning the nature and distribution of seabed sediments.

What is a Shom Z chart used for?

A Shom Z, or Zonex, chart includes an additional overlay identifying the limits and designation of exercise and firing areas used by maritime forces.

What is a Shom Raster nautical chart?

A Shom Raster nautical chart is a digital representation of a nautical chart. Shom raster products are distributed, among other formats, as GeoTIFF files, with a resolution of 300 dpi and WGS 84 georeferencing associated with the Mercator projection.

Is a Shom L chart suitable for recreational sailing?

Yes. Shom L charts can be used for coastal navigation, cruising, passages and harbour approaches, depending on the geographical area and scale of the selected reference.

Is a Shom paper chart useful when using GPS or a chartplotter?

Yes. A paper chart can be used to prepare a route, maintain an overall view of the area and provide a cartographic reference independent of electronic equipment. It can therefore complement the digital navigation systems used on board.