How to choose a mooring area?
The nautical charts show certain anchorage areas, but not all are indicated. As the saying goes, "Everything that is not forbidden is allowed". Also, during your navigation, you will have the possibility toanchor your boat in many different places.
On the other hand, nautical charts also define forbidden sectors where specific regulations are sometimes imposed to organize the anchoring of your boat. This is the case, for example, of the National Park in Port-Cros and Porquerolles in the Mediterranean. The sailing instructions indicate the restrictions or special conditions inherent to sailing and mooring in these areas. For example, be aware of underwater cables and wrecks. These restrictions often result from the will to protect the seabed and more particularly thePosidonia Herbarium, classified as a protected species since 1988.
A sheltered cove, in addition to putting less strain on the mooring equipment and the boat, will allow you to focus on comfort on board. Anchoring is a matter of anticipation as much in the technical preparation as in the explanations to be given to the crew and the distribution of roles.
Thus, the success of a good mooring depends on its preparation. So, in order to choose the right area to anchor your boat, make sure that the selected place meets these four characteristics:
- The good performance of the seabed
- The depth of the mooring area, theevaluation of the current and the tidal situation (tidal range and coefficient)
- Safety of the mooring area
- Availability within the anchorage area
What factors should be taken into account when choosing a mooring area?
When it comes to choosing a mooring area and the appropriate mooring technique, there are three key factors to consider to ensure that you can anchor safely: the nature of the bottom, the tide and current, and the weather.
The nature of the background
Anchoring depends on the nature of the bottom. Nautical charts indicate the composition of the seabed. The anchor generally holds well on sandy or clayey bottoms or on compact sand. Grassy bottoms (except for Posidonia) provide good holding power when the anchor can penetrate the bottom. Rocks, coral, gravel and liquid mud present more difficulties.
The tide and the current
Generally, the direction of the waves corresponds to the wind bed and the boat, aligned on the anchor chain, gives an appreciable comfort. However, it happens that a 90° angle between the direction of the waves and the direction of the wind generates an unpleasant and uncomfortable movement, the boat "rolls"... nothing more unpleasant than a rolling anchor.
If the anchorage is located in a tidal zone, the length of the anchor line must be adapted to the depth of the high tide and obviously not only to the conditions of the moment. Therefore, the knowledge of the tide times and the coefficient will impact the avoidance zone to be considered and thus the dangers and obstacles for your boat likely to be located in this zone.
The weather, along with the type of coastline, largely determines the safety of the anchorage.
Consulting the weather forecast is imperative before setting sail, whether for a few hours or several days. Indeed, for an anchorage, this operation is all the more useful since the weather conditions can change and the purpose is to find an anchorage sheltered from the wind for the duration of the anchorage.
The anchorage must offer good protection at the time of anchoring and requires anticipation of the coming conditions. In case of a southwest wind, and if it is likely to change to northwest, the sheltered anchorage should protect both sectors at the same time.
In the same way, if you plan to go ashore in a dinghy, you must take this possibility into account by choosing the right anchoring place.
To check the weather :
➡️ VHF channels 63 and 79
Assessing the mooring area
Little practiced,observation by making a slow turn around the anchorage area to determine the anchoring technique to use is essential. In addition, this choice must also be determined according to the boats already anchored in the anchorage area. Estimating the effects of an overturn or of a strengthening wind, the anchor's hunting, the possibility of dropping more chain length, allows you to anticipate situations that could quickly cause inconvenience.
Which wetting technique to choose?
There are different mooring techniques, and it is not always easy to choose which one to use depending on the mooring area and the environment. Here are some examples:
Once you have found the ideal place to anchor your boat, you must stop the boat facing the wind or the current (whichever is stronger). Then, once the engine is disengaged, sail the right length of mooring line, at least 3 times the height of the water: the boat drifts backwards and tends to fall. Navigation manuals recommend a length of 3 to 5 times the total water height, i.e. depth + tide height + davit height. Once the desired length has been reached, the boat should be beaten back gently. A series of jerks on the chain indicates that the anchor is dragging and has not hooked the bottom; on the contrary, a low tension tends to indicate that the anchor has hooked. The more chain, the better the anchor will hold.
Increasing engine power to back up will help to ensure that your boat is properly anchored. Finally, tie the mooring to a cleat on board.
On a rocky bottom, there is a risk of not being able to bring up the anchor. Also, the mooring line is a solution to preserve the mooring line.
The mooring line is a simple device that consists of hitting the anchor's diamond, a cable or a rope, connected to a buoy and allowing the anchor to be located. The length of the mooring line corresponds to the height of the water with a small additional margin. This operation is called "setting an anchor".
Iron hand (mooring hook)
The windlass is not designed to withstand a horizontal force. Also, the "iron hand" or mooring hook allows to relieve the tension of the chain mooring.
During the day, display the anchor ball (indicates that the boat is stationary, not maneuvering and without watch) and at night, the anchor light.
In order to monitor the anchorage, once it's in place, you need to make sure the anchor is hooked up properly. Also, most GPS units have a feature that lets you set a mooring circle. As soon as you cross the area previously defined in your GPS, an alarm sounds. However, you also have the option of using a more traditional method. It consists of taking three landmarks on the coast (landmarks). Once set, you can take a bearing and observe the movement of these markers.
This method is used to limit the turning radius, but is not suitable for bad weather. Anchors work alternately but not at the same time. Also, it is important that the anchors are set between 60 and 90 degrees from each other.
Anchoring in a river, for example, greatly limits the turning radius. Do not use this technique in bad weather. The principle is to anchor two anchors (one in the bow, the other in the stern) to keep the boat on its axis. You can replace an anchor with a line or a hawser struck on a tree.
This mooring technique is ideal in bad weather, regardless of the mooring area, when the wind or current is strong. The technique is based on the use of two anchors. A second anchor is anchored in the extension of the first one. Thus, they work together and prevent the boat from hunting.
"Anchorage represents for the yachtsman what wild camping is for the camper. An immense space of freedom, the discovery of the coast by the sea allows to discover fabulous landscapes. What more beautiful moment in the life of a sailor?
Cordouan lighthouse, the most popular anchorage area in the Gironde estuary
The Cordouan Lighthouse is located 7km offshore from the mouth of theGironde estuary.
The lighthouse lights up and secures the traffic in the two passes allowing the access to the Gironde estuary:
- The Grande Passe de l'Ouest, marked out at night, which runs along the north shore from the Coubre bank.
- The South Pass, which is narrower and not marked at night.
From Port Médoc, the navigation does not present any particular difficulties in good weather. When swell and wind are moderate, it is advisable to adopt a great caution on the spot. Indeed, sandy and rocky bottoms of 1 to 5 meters surround the building.
The lighthouse is located on a plateau and adjoins a sandbar that moves from year to year.
It offers a beautiful anchorage that can be used from mid-tide down to mid-tide up near the sandbar. This configuration allows you to reach the lighthouse on foot while leaving your boat at anchor. The swell can be more important at the rising tide and sometimes causes a significant chop.
➡️ Discover the different navigation circuits on the Gironde estuary from Port-Médoc