Anchoring  Basics 
 for  First  Time  Cruisers

The information presented is applicable for that part of the Ottawa River between Lake Deschenes and the Chats Falls dam, although it's probably valid for other areas of this body of water. It also assumes that most first time cruisers start off with boats in the 20 to 26 foot range (boats 6 to 8 metres in length).

Choice of Anchor
  • *** illustration of anchor types ***The Danforth type anchor is one of the most popular on the Ottawa River. Larger boats in the 25 to 26 foot (6 to 8 m) range will do quite nicely with a 13 lbs (6 Kg) Danforth-type anchor, which is rated for boats up to 30 feet in length. An example would be the Danforth Standard S920.

  • If storage space or weight is a problem, smaller boats under 24 feet (7.3 m) can safely use an 8 or 9 lbs (4 Kg) Danforth-type anchor (although it's always a good idea to use a slightly oversized anchor). An example would be the Danforth Standard S600.

  • Buy a good quality unit. There is no need to get the most expensive danforth-type anchor, but stay away from hardware-store-specials. If the shape of a danforth-type anchor deforms under pressure, or one of its flukes goes slightly off angle, it will lose much of its holding power.

  • Boats in the 25 to 26 foot range may also consider using a 20 to 25 lbs plow (CQR) or a 7.5 kg (16 lbs) Bruce Anchor. While these are heavier, more expensive, and more difficult to store than the Danforth, they are popular because they offer good performance over a wider range of bottom conditions. The Plow is preferred for bottoms covered with weeds, and the Bruce has a reputation of providing good holding power with a shorter scope (amount of anchor line let out).

Choice of Anchor Rode (anchor line)
  • A nylon rode has strength and elasticity. This latter characteristic helps absorb the shocks that could cause the anchor to break out. Note that much of this elasticity will be lost if you choose a nylon rope that is too thick for the size and weight of your boat.

  • Boats up to 22-23 feet in length, and displacing 3000 lbs (1360 Kg) or less should use a 3/8" nylon anchor rode. Boats in the 25 to 26 range that displace closer to 5000 lbs (2268 Kg) will probably want to use a 1/2" rode. A 150 feet (45 m) of anchor line should be enough for boats which do most of their anchoring in water that's 8 to 16 feet (2.5 to 5 m) deep, which is usually the case in many areas along the Ottawa River. However, you may want to bring 200 feet (60 m) of rode just in case you end up anchoring deeper water.

  • The nylon rode should be attached to at least six feet (2 m) of fairly heavy chain, which, in turn, is shackled to the anchor. It's even better to use 20 to 25 feet (6 to 8 m) of chain . The extra weight of the chain significantly increases your anchor's holding power. Use of a chain will also help protect the nylon rode from chafing against rocks and other debris on the bottom.

Anchoring Techniques
  • Needless to say, you should choose an anchorage which will offer protection from the expected winds and waves. Until you gain a bit of experience, it may be wise to stick to known anchorages.

  • Most of the boats on the Ottawa River between Lake Deschenes and the Chat Falls Dam opt to swing on a single anchor. It is highly advisable to use the same technique as everyone in your anchorage.

  • Choose a spot to drop the anchor in terms of water depth, bottom conditions, and the location of other boats in the anchorage. Study the chart for information about depths and bottom conditions. Head into the wind or waves when approaching the spot where you plan to drop your anchor. Try to visualize where your boat will end up once it is anchored. Depending on the depth of the water and amount of rode let out, your boat will will probably end up 35 to 55 feet (10 to 16 m) downstream or downwind from the spot your anchor actually digs in.

  • The anchor should be carefully lowered from the bow (not thrown overboard). As it touches the bottom put the engine in reverse and slowly back the boat up while continuing to pay out anchor rode. Once enough rode has been let out to equal approximately 3 times the depth of the water, snub the line around a cleat to see if the anchor is starting to dig in (you should see and feel the tension on the rode). When the anchor begins to dig in, let out the additional rode required for the desired scope and secure the line. And finally, you can make sure the anchor is properly set by backing down on it under power (rev-up your engine in reverse for 10 to 15 seconds).

  • If you find your anchor doesn't want to dig in, you may have to restart the entire process. If you continue to experience problems, consider anchoring in a different spot. You may also to want to raise the anchor completely out of the water to verify that it hasn't been fouled with debris from the bottom (e.g. an old piece of wood stuck between the flukes of a Danforth).

  • It's a good idea to take a fix on a few objects on shore so you will be able to verify that you are not dragging your anchor. You may want to repeat this exercise if the wind shifts and your boat assumes a new position within its swing circle.

  • Sooner or later you have to break out the anchor. If you haul up your anchor while the boat is moving, be sure the force of your boat's bow wave doesn't cause it to bang against the hull. Dunking the anchor and chain in and out of the water will help to wash off any mud.

Scope and Swing Circles
  • Scope is the ratio between the amount of anchor rode let out and the distance to the bottom of the water (the distance to the bottom includes the height of the bow above the water). For example, if you anchor in 10 feet of water and your bow is 4 feet above the water, the distance to the bottom should be calculated at 14 feet (4 + 10). In this situation, letting out 42 feet (3 x 14) of rode would result in a scope of 3 to 1, and 98 feet (7 x 14) of rode would produce a scope of  7 to 1.

*** illustration of different scopes being used by a boat ***
  • The holding power of an anchor increases with a longer scope. A scope of 3 to 1 is the minimum that should be used under calm conditions when anchoring for a few hours during the day. Overnight anchoring requires a scope of at least 5 to 1, and if it's going be windy, this should be increased to 7 to 1. A scope of 10 to 1 is not too much when anchoring in stormy conditions.

  • A crowded anchorage can have an influence on the amount of scope people use. A long scope will produce a wide swing circle for a boat at anchor. Ideally, the swing circles of various boats in an anchorage should not overlap with each other. As a result, in a crowded anchorage, many people will attempt to use minimum scope possible (i.e. barely 5 to 1 when anchoring overnight in calm conditions).

  • People on a short scope will generally let out more rode if the wind picks up in the middle of the night. If they are in a crowded anchorage, they may sleep lightly knowing that the potential for overlapping swing circles has also increased (along with the possibility of boats bumping into each other).

    *** illustration of swing circles in an anchorage ***

  • In a perfect world, all boats in the anchorage would swing in unison in response to the same wind, current, and waves (and thus eliminate the problem of boats bumping into one another when they have overlapping swing circles). In reality, boats come in assorted sizes, keel configurations, and above water profiles. They react differently to the wind, waves, and current, and in varying degrees, swing out of unison. The occasional and minor overlaps in swing circles will probably not result in two boats to make contact with each other, but it can happen.

Other Considerations
  • Anchoring etiquette dictates that the use of an anchorage is on a first come, first serve basis. Boats coming later have to respect the space and swing circles of those already anchored.

  • It is always a good idea to slowly motor around an unfamiliar anchorage before dropping the hook. If you have a depth sounder, this will be a good time to use it. The same practice is applicable for crowded anchorages. There's always a chance you'll discover space for one more boat when taking a slow tour around the anchorage.

  • The use of an anchor light is a requirement when anchoring overnight. Late arrivals will have a difficult time spotting your boat without such a light on dark overcast nights. Fortunately, rigging an appropriate light is a fairly simple matter. See the project on making an "Anchor Light".

  • You should be aware when anchoring (especially during the evening hours), that almost everyone else in the anchorage will be observing you (as discreetly as possible, of course). It's just the way it is. You'll do it too. Just remember that it's not the anchoring, or the need to re-anchor, which separates the beginners from the experts - it's the amount of yelling and chaos that breaks out between the person handling the anchor, and the person manoeuvring the boat (develop a set of hand signals to communicate with one another).

         Text and graphics by Michael McGoldrick.
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