Anchoring
The anchor, often a symbol of boating, is an important tool for safe boating. Oddly, it is not on the Coast Guard required safety list, but that may change. The Coast Guard is considering adding the anchor to the required equipment list. The traditional Navy anchor, depicted above, is generally not a good anchor for use on a recreational boat.
Anchor Position
A properly anchored boat can withstand heavy seas and protect the boat and boater from harm. A power boat with engine failure is subject to any wave or passing storm. An anchored boat will face directly into the wind. Typically the bow of the boat is the portion of the boat best able to "take" oncoming waves. Thus, a boat should always be anchored from the bow.
Never anchor a boat by the stern. This is the portion of the boat with the least freeboard. A strong series of waves will quickly flow over the transom and fill the boat. A bilge pump may keep up for a while but once the battery is discharged, the boat will fill quickly and sink.
Anchor Type
Even though anchors are used most often by recreational boaters to "park" their boat while swimming or fishing, anchors are also critical equipment in times of emergency. Anchoring may be a safety measure if your boat becomes disabled.
|
Choose an anchor that fits your boat and the boating conditions. The plow-style anchor is good for most boats and gets its holding power by plowing into bottom sediments. |
 |
|
The fluke-style anchor (commonly referred to as Danforth) is similar to the plow style but is more lightweight. It is also good for most boats and gets its holding power from its pointed flukes digging into bottom sediments. |
 |
|
The mushroom anchor gets its holding power by sinking into bottom sediments. It should not be used to anchor boats larger than a small canoe, rowboat, small sailboat, or inflatable boat since the holding power is weak. You should never depend on a mushroom anchor to hold your boat in rough water or weather. |
 |
Anchor Rope
No anchor is complete without an attached line. This "rode", as it is called, secures the anchor to your boat. Nylon has become the mainstay of rode, since it has the ability to stretch under load. This ability to stretch absorbs the shock present under heavy weather conditions. The end of the rode typically has a thimble attached to it. Chain is attached to the nylon rode and then attached to the anchor. A good rule of thumb is to attach a length of chain equal to the length of your boat. The chain gives some added weight to the rode allowing the anchor line to lie in a more horizontal plane. This helps the anchor to dig in more deeply to the lake or ocean bottom. The chain is also much more chafe resistant than nylon. As a boat swings on the anchor, the bottom could rapidly wear through a nylon line. Commercial boating catalogs will list the appropriate size of line for a given size of boat. It never hurts to get one size bigger than indicated in the chart since this is the line you and your boat will be depending on in an emergent or heavy weather situation. Choosing an anchor size larger than indicated for your boat will give a more secure attachment to the bottom.
Anchoring Technique
Once a site is chosen for anchoring, the anchor if not already, should be attached to the rode in the anchor locker. Be sure to secure the "bitter end" to a bow cleat on the deck or in the anchor locker if a cleat is present there. Nothing is worse than lowering your newly purchased anchor into the water and seeing the bitter end go with it. The anchor should be lowered into the water, not thrown. The anchor can tangle upon itself if thrown into the water preventing its firm attachment to the bottom. Once the anchor hits bottom, the pilot of the boat should begin backing the boat up. Continue to play out rode until the pre-determined amount of line has been let out. Secure the rode to the cleat. Have the pilot of the boat back the boat until the anchor firmly sets. A properly set anchor will resist the pull of a boat under significant power. Some boaters will let out some rode, set the anchor, then let out the remainder of the rode. Lake Tahoe is an excellent place to practice anchoring since it has a generally sandy bottom. As the afternoon wind comes up your anchoring "set" will be put to the test.
Anchor Scope
Not to be confused with mouthwash, this is the length of rode used to anchor your boat. Generally the following rules apply. The longer you plan to stay "on the hook" at a particular location the more scope you should have. Thus a "lunch" hook may only need a scope 2-3 times water depth plus freeboard whereas an overnight hook in heavier wind may require a scope of 7. Be sure to include the freeboard of your boat when calculating scope.
For example, if you are planning on a "lunch" hook in 15 feet of water and desire a scope of 3 you would do the following calculation:
Depth of water = 15 feet Scope desired 3 Freeboard of boat = 3 feet
The length of rode needed for a scope of 3 is: water depth (15 feet) + freeboard ( 3 feet) equals 18 feet. To achieve a scope of 3 you would need to let out 54 feet. A scope of 3 is not 45 feet. The freeboard must be added to the water depth before calculating your scope!
Anchor Retrieval
Retrieving the anchor is generally easy. The rode should be "flaked" or laid back into the anchor locker in a back and forth figure eight pattern. This allows the free flow of rode the next time you anchor. Should you anchor hang up on a rock or log, have the boat's pilot put the boat into forward gear after you have secured the rode to the the deck cleat. This will generally help you free the anchor from the bottom. Failing this, someone may need to dive down to the anchor if the boat is in relatively shallow water and conditions permit this to be safely done.