Laying a Second Anchor

Rev. 7-22-2024.

 ( One of many draft posts as I was trying out ideas for my eventual book, "Rigging Modern Anchors.")

 For the most part, a single working anchor is a simple and dependable practice; nothing to tangle, a simple procedure, and since others do the same, boats will generally swing the same way in response to wind and current. However, on a holiday weekend you may find somebody has dropped way to close and you want to limit your swing in that direction. You may find that your boat swings differently from the others. The bottom may offer terrible holding; thin stilt over rock-hard clay is a common Chesapeake "bad" bottom; it feels like you have a set... until you pull, whereupon in tracks through the silt but refuses to go deeper and cannot be depended upon to reset in a shift. Severe storms may be coming and perhaps you are anchored too darn close to rocks to tolerate any dragging. Perhaps other boats moved in around you (herd mentality), restricting swing in one direction. All of these coincided  for us yesterday.

The greatest hassle of setting two hooks is the resulting tangle if the boat spins. If both are lowered from rollers, with the rode passing through a hawse pipe and  ending deep in the bilge, the twists are not easily removed. A simple solution:

I have since dispensed with chain, using a Dyneema leader with a webbing chafe cover. Reducing weight on the shank helps the light weight anchor to set.

• Get a light secondary anchor. I've been using Fortress anchors for this purpose for 15 years and love them. I've never had one drag.
• Do Not keep the second anchor on rollers. We keep ours in a stern locker, from where it is most often deployed. The rode lives in a bucket
• Keep the rode short; only enough for the day's situation. We keep 50 feet of rode on the anchor for most uses (in 6 feet of water with a 15 foot bridle this gives 7:1 scope). If we need more, we have two docklines with spliced loops in the both ends that we chain together with cow hitches. But only deploy enough for the exact scope you want.
• Connect the second rode either to your bridle or to the main rode a few feet below the bridle. We typically connect the second rode to the bridle plate with a strong stainless carabiner, but a Prusik hitch is good too.

Because the second rode is not connected to the boat, only to the rode, it is simple to disconnect and unwind if the boat has spun.

 A second anchor can actually increase the strain on the anchors, if the angle is too great. The optimum angle for holding is almost always 90-120 degrees; less, and the anchors will still need to reset when the wind shifts, more and the tight-rope effect really piles up the force in a cross wind.  The notion that 2 anchors set close to each other can increase holding is plainly false; even a small wind shift places all of the load on one, and the potential for the second rode to foul the primary anchor is too great. The case that tandem anchors provide increased holding is very weak, though it has proponents. The problem is re-setting; the second anchor will generally keep the primary on it's side, preventing a good bury, and 150% of  standard rode length is required (the second anchor "lifts" the rode by providing tension from the end of the rode).

Generally we use this procedure:

• Set the first hook at longish scope (14:1) and set.
• Lower the second hook from the transom, bringing the rode forward outside all of the rigging. If I had a heavier anchor I would mount a roller on the stern. This would also make it easier to load into the tender, when that is needed.
• If we are in shallow water, I can generally feel the hook in with that 35 feet of scope. If not, we shorten the primary as need to get in the right position.
• Take in the main rode to desired scope (7:1?).
• Give the secondary hook a better pull, just feeling it in.
• Connect secondary rode to the primary as above. Let at least 4 feet of chain out, so that if the boat spins, the chain absorbs the twist.
• If you're really expecting a blow and want to power set these, wait about 20 minutes and back at a 90 degree angle to a line between the anchors.We've only done that a few times, when we could hear the storms and knew we were anchored in silt. Each time we got to watch a few less diligent--or perhaps just unlucky--souls drift to leeward.

We can row an anchor out if the above procedure won't place the anchor in the right spot... actually, we've done this just once, to see if we could do it from the kayak (no problem). I've run big anchors out for other folks, helping them kedge off, using our tender. However, generally we can place the second anchor from the main boat, by using the engines to swing the boat against the primary anchor, though even that assistance is very seldom needed.  

Tip: the rode for the secondary anchor should be mostly or all rope with chafe protection. Because there won't be any yawing, chafe will be minimal. Second, it will be much easier to take out. Finally, it's not your sole anchor, and in the infinitesimally small chance the rode cuts (I've never heard of a V-twin rode cutting--there isn't enough motion), you still have the other anchor.

From "Rigging Modern Anchors." See the bookstore for the more up-to-date and complete explanation.

What if the boat is hanging to the second anchor in a strong wind in the morning? Attach an extension line and ease it off until you are hanging from just one anchor. Retrieve the main anchor while you are drifting back; this should be easy, since you may drift right over it. Then motor back up to the secondary and retrieve. If you don't want to let go, attach a long (150 feet) line to the secondary, release, and follow the same steps. Easy if you have a plan.

With practice, this typically adds about 5 minutes to the anchor drill and has never caused a bit of trouble.