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Anchors Aweigh

Lake Tahoe is actually a great place to learn how to anchor, if you donít try to drop your hook in the middle of the lake. The water is clear so you can see and feel the line when the anchor grabs the bottom. Try that in San Francisco Bay. Every boater needs to know the art of anchoring. You need it for protection and for gunk holing in some secluded cove. Anchoring equipment is called ground tackle. The type of ground tackle you need depends on your vesselís type, weight, and length. Also important are the characteristics of the bottom and the depth of water in which you will anchor. To be adequate, your ground tackle must hold your boat securely under the most adverse conditions. The line attached to the anchor is called a rode. It usually consists of a heavy nylon line and at least six feet of chain between the anchor and the nylon line. The chain helps the anchor grab the bottom and protects the nylon line from chafing on a rocky bottom. There are many types of anchors, but the most popular for small recreational boats is the Danforth. It is a lightweight anchor with long, narrow, twin flukes these are the anchor parts that dig into the bottom. A Danforth Anchor is of little use on a grassy bottom. It slides across the grass rather than digging in. It works well in mud, and sand, but may hang up in a rocky bottom.

An anchor holds best when the pull of the rode is as nearly horizontal as possible. For this reason, holding power increases as you increase the length of the rode. The Scope of the anchor rode is the ratio of its length to the depth of the water. Normally, a scope of 7:1 is adequate for holding a boat. This means there should be seven feet of rode for each foot of water depth. Letís suppose the water is ten feet deep and the chock on your boatís deck is four feet above the waterís surface. When you multiply this by seven 10 feet of water plus four feet of line from your deck to the waterís surface is 14 x 7= 98 feet of line; you can see even a small boat needs a lot of line. A scope of 5:1 is marginal. A scope of 3:1 is poor unless the weather is excellent and the bottom is good for anchoring. With a 3:1 scope, you must watch your anchor at all times. A 3:1 scope is usually enough if you stopped to eat or to fish and you stay on your boat. A storm anchor should have a scope of at least 10:1. Even at that, you should maintain an anchor watch.

The first step in anchoring is to check the nature of the bottom and its depth. Here on the lake you can usually do see the sandy bottom. If your bottom is satisfactory for anchoring and the water depth is not to great, head your boat into the wind. Reduce your speed and make sure your anchor rode can run out freely. Reverse your engine and when the boat starts to move backward, lower your anchor carefully over the bow. Never throw it! And make sure that you are not standing on or tangled in any part of the line. You could very well find yourself traveling with your anchor. Be certain, too that you tied the end securely to the boat. If your anchor and all your rode goes overboard. Well most marine stores take credit cards. Take your engine out of gear, and when you have paid out enough line, make the line fast to a forward cleat. Never tie off to the side or the stern of your boat. It may be convenient but it is dangerous. Large wakes or storm waves can swamp you when you are anchored from the side or stern. When you keep your hand on the line you can tell if your anchor has dug in. When it vibrates, the anchor is sliding across the bottom. When it just skips, pay out more rode until it digs in firmly. You will feel a definite halt in the drift of the boat when it digs in. After you have a good "bite" on your anchor; turn off your engine. When you have finished anchoring, take sights on some stationary objects on shore. Line them up with other objects. Should your anchor drag, you can tell by checking these Ranges. If your anchor starts to drag let out more line.

When you are ready to leave start your engine and be certain that it is operating properly. Then go ahead slowly to a position directly above the anchor, taking up the rode as you proceed. Usually, the anchor will break free of the bottom when you are over it. If your anchor does not break free, it is probable fouled. Make the line fast to the bow and run your boat SLOWLY in wide circles with a taut line. You may be able to free the anchor.

By the way if you wanted to anchor in the center of the lake. The average depth is 900 feet + 4 feet of line from the deck to the waterís surface multiply by 7 = 6,328 feet of rode. When we anchor there I usually have my wife take in the rode.

 

 
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