Fouled Anchor Troubleshooting Guide And Causes

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You have stowed your belongings in the cabin, baited the rods, and readied the crew for your departure only to find that upon pulling anchor that it won’t even budge! Unfortunately, this happens all too often, particularly in crowded ports or overground with poor holdings like weed, shoaling reef, or a rough rubbly bottom.

Cutting an expensive anchor loose is a quick way to ruin a day of boating so in this article, we will discuss common causes, prevention tips to avoid this unlucky predicament but most importantly we will provide the ultimate troubleshooting guide for fouled anchors together with a step by step process.

What Are Some Common Causes for a Fouled Anchor?

The seafloor is scattered with innumerable obstructions that can impact the effectiveness of anchoring safely.  Typically, the ideal anchoring ground is safe and secure anchoring is in sand or mud but there is plenty of other terrains that can cause issues; think rocky shaly ground, rubbly reef, seaweed beds, or kelp forests to name but a few.

Then consider other natural obstructions like rotting logs, roots, boulders not to mention a whole host of man-made objects that can foul an anchor. If you are an avid boater, chances are you have encountered a tight tangle with another vessel’s chain or anchor, particularly in busy ports.

But these are only just two man-made obstructions below the surface, we have seen it all and the objects really are endless; with a long list of varying types of marine debris, heck we have even see discarded outboard motors being pulled up with a fouled anchor!

What are the Top Methods for Retrieving a Fouled Anchor?

Fouled Anchor

Use the Natural Momentum of the Boat to Loosen And Free Your Anchor

  • To start, position the bow of the boat directly above the anchor. In light wind conditions, this will be as simple as shifting the motors into neutral and slowly winching into the anchor chain until it becomes taut. In heavier wind conditions this might involve a crew member heading to the bow to spot the anchor chain and direct the helmsmen toward the direction of the anchor chain, slowly winching in the chain as you approach.
  • Tie off the anchor line by wrapping the line once around a bow cleat to hold the line taut. Be sure to only clear it off once in case you need to release the line quickly if the boat changes direction.
  • As the boat dips into the trough of a wave, cinch into the now slack anchor line. Then when the boat rises on the next peak of a wave the upward motion might be enough to dislodge your anchor. If there are no waves a similar motion can be attained by moving all crew members to the bow, clearing the slack in the line, then moving everyone to the aft of the boat to create this same pivoting motion to work the anchor free.

Backing the Anchor Out

  • With the bow of the boat still in position above the anchor and the anchor line partially cleared, the engines shift into gear.
  • With the engines engaged gently move over the anchor in the opposite direction from which you originally set it. As you edge forward cinch the anchor line in to keep it taut. With this forward propulsion, the force in the opposite direction might be enough to free your anchor.

Retrieval Using a Shackle and Buoy

This method works by using a shackle and buoy that serves as a pulley system. As the shackle moves down the anchor line the force from the boat in conjunction with the buoyancy of the buoy will help to free the anchor and float it to the surface. Note that the buoy must be large enough to support the weight of the anchor and the chain.

  • Attached is a shackle to a few feet of line and floating buoy.
  • Attached this assembly around your anchor line and begin maneuvering the boat past the anchor at a 45-degree angle.
  • Keeping this forward motion, you will inevitably notice the buoy becomes submerged below the surface. Hold fast, keep this forward direction until you see the buoy rises up to the water’s surface which will signify that the anchor has pulled free.

The Last Resort…

If after trying these previous methods without avail, your last resort is to don those swimmers, grab a mask and snorkel and dive down under the water to investigate! Sometimes it is a simple matter of untangling some marine debris from the anchor.

Or on occasion to get a visual of the direction of the set anchor might assist in a more successful attempt to back the anchor out.

If all efforts fail it may be possible to retrieve the anchor at a later date at low tide or with the assistance of a scuba diver. Attach a buoy or float as a marker, backed up by an added pin on your chart plotter of its location. This way you can arrange to come back another day to attempt a recovery mission.

Learning From Your Mistakes

Prevent a Snagged Anchor

Here Are Some Easy Steps you can Take Next Time to Prevent a Snagged Anchor

Have the right gear

Anchoring with inadequate ground tackle is not only unsafe but it can also make the anchoring process very arduous and, in this case, costly if you lose your anchor entirely. Some additional accessories that can be added to ground tackle to make life easier could be:

Anchor Swivel

These multidirectional swivels components are attached to the shank of the anchor and allow plenty of movement and rotation in the anchor chain as the boat turns whilst on anchor. This limits the additional strain on the chain and can even prevent a snagged anchor

Anchor Saver

A small device is attached from the shank of the anchor to its crown, using indirect pressure to dislodge the anchor from the tops.

Ensure you do your research

With plenty of resources out there is no excuse to learn about the anchorages you intent to visit, paying private attention to possible obstruction in the anchorages, as well as the type of holding to expect.

Plan your approach & exit

Consider the wind, any current, and the proximity of other vessels, allowing plenty of room from any possible obstructions on the surface.

Establish a visual of the bottom

Once you find a suitable location to anchor with an adequate depth, it is advisable to circle over this vicinity to inspect the surroundings looking out for uneven ground or obstructions under the surface. This can be established by view its depth sounder or if conditions allow having a crew member spot at the bow.

Attached to trip line

Also known as an anchor buoy, makes an effective tool in retrieving a stubborn fouled anchor, but also gives a visual to other boaters of their anchor’s location, to prevent them from dropping their hook in the same spot. Simply attach a line to the eye on the crown of your anchor and tie the other end to a buoy, allowing for enough line so that the buoy can float vertically above the anchor’s position.

With the line attached to the head of the anchor instead of the shank, this gives an alternate point of purchase to pull the anchor in the reverse position if it becomes fouled. With any trip lines, it is very important to consider the tidal movement. Too little slack in the line with an incoming tide may result in dislodging or floating your anchor off the bottom, resulting in a drifting vessel.

Take note of the depth and any tidal rise that may occur during your anchoring timeframe, then add an additional 10 feet to this length of line to compensate for any unforeseen circumstances.


Question: What is a Fouled Anchor?

Answer: Foul is a nautical term meaning tangled, or more generally that something is wrong. So, a fouled anchor refers to a boat anchor that has become prevented by some obstruction on the seafloor and as a result, the anchor is not easily retrieved.

Question: What is the Correct Boating Etiquette for a Discarded Anchor?

Answer: The cardinal rule for discarded anchors, particularly in busy ports or crowded anchorages is to always use a buoy or float to mark the location of your anchor as well as notifying the port authority of this new obstruction in the water. Not only will this help if you return to retrieve it on another day, but will also reduce the chances of someone else fouling their anchor in this obstruction and also reduce some risk of damage to their vessel.

Question: What Type of Anchor is Best for Grassy or Muddy Anchorages?

Answer: Fluke anchors, also known as Danforth anchors are ideal for terrain that has a grassy or muddy bottom. These anchors have a pointed fluke that digs into the ground more easily.

Question: What Type of Anchor is Best for Rocky Bottomed Anchorages?

Answer: Plow and grapnel style anchors are better suited to terrain that is rubbly or rocky. But note, plow anchors are not suitable for grassy or muddy terrain as they are not designed to dig into the ground as easily as a fluke, claw or delta style anchors.

Question: What is the Basic Technique for Anchoring?

Determine the water depth where you intend to drop anchor and calculate the correct amount of anchor scope to release. Ideally, this is a ratio of 7:1. With the vessel facing into the wind and set to neutral release the anchor from the bow of the boat, slowly letting out the scope of the anchor chain or roll as you drift backward.
Once the adequate scope has been released secure the anchor line to a bow cleat or affixes a bridle or snubber to release the pressure from the winch. If conditions are light, you may like to set the anchor by reversing the vessel slightly to ensure the anchor has dug into the holding below.
Ensure there is no drag using a landmark or onboard electronics to measure movement.

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