How to Anchor a Catamaran Like a Pro
Anchoring a catamaran requires some key considerations to ensure your vessel stays secure, particularly in changing wind and sea conditions. While the basic principles of anchoring remain similar to those of a monohull, there are some key differences that catamaran owners need to be aware of. In this guide, we’ll walk you through the best practices for anchoring a multihull safely and effectively.
1. Choosing the Right Anchoring Spot
Before dropping anchor, selecting the right location is crucial for a safe and secure hold. Ask yourself the following:
Is the seabed suitable for anchoring? Sand, mud, or gravel bottoms typically offer the best holding.
Do I have enough swinging room? Consider how your boat will move with changes in wind and tide.
Am I using the right anchor for the seabed conditions? Different anchor types perform better in certain conditions.
2. Dropping Anchor – Step-by-Step
Once you've found the ideal anchoring spot, follow these steps to ensure a secure hold:
Step 1: Approach Into the Wind
Like a monohull, bring your catamaran head-to-wind before lowering the anchor.
Keep in mind that catamarans drift more quickly than monohulls, so maintain control while maneuvering.
Step 2: Lower the Anchor & Pay Out Chain
Lower the anchor onto your chosen seabed and allow the boat to drift back naturally.
Use the 5:1 scope rule: For every 1 metre of water depth, release at least 5 metres of chain.
If you're anchoring in 5 metres of water, you should let out at least 25 metres of chain.
In stronger winds, a greater scope (7:1 or more) is recommended for added security.
Step 3: Test Your Anchor Hold
Once you’ve let out the appropriate amount of chain, check that the anchor is firmly set.
Use your engines in reverse to ensure the anchor digs into the seabed.
Line up a reference point onshore and check that it remains in place as you back down.
3. The Key Difference: Using a Bridle on a Catamaran
Unlike monohulls, catamarans tend to sway excessively at anchor due to their wide beam. To prevent this, you’ll need a bridle system to stabilize the boat.
How to Set Up a Bridle:
Measure the Bridle Length:
A general rule of thumb: the length of your bridle should be roughly equal to the beam of your catamaran.
If your catamaran is 7 metres wide, then each arm of the bridle should be around 7 metres long.
Attach the Bridle to Your Anchor Line:
Secure the bridle to the anchor chain using a rolling hitch or a chain hook.
Let out additional chain so the load transfers from the chain to the bridle.
Ensure Proper Weight Distribution:
Keep a loop of chain between where the bridle attaches and the bow of the boat.
This helps absorb shock loads and prevents jerking, making for a more comfortable night at anchor.
4. Choosing the Right Anchor for a Catamaran
Catamarans are typically lighter than monohulls of the same length but have much higher windage. This means they are more affected by wind and require larger anchors for secure holding.
🔹 Anchor Size Rule: Always go one size up from the recommended anchor size for a monohull of the same length.
🔹 Example: If a 45-pound anchor is recommended for your boat, opt for a 60-pound anchor instead.
5. Strength Matters – Secure Your Bridle Properly
The bridle will take the full force of the boat’s load during strong winds and storms. It’s critical to attach it to strong, reinforced points on your catamaran. Weak attachment points can fail under pressure, putting your vessel at risk.
Final Tips for a Secure Anchoring Experience
Monitor your holding: Check that you’re not dragging by setting visual markers.
Adjust scope in stronger winds: More chain = better holding power.
Check your bridle connections regularly: Look for wear and ensure the setup is secure.
Choose a safe anchorage: Avoid anchoring in high-traffic areas or close to rocky shorelines.
By following these steps, you can ensure your catamaran remains securely anchored, providing peace of mind whether you're staying overnight or just stopping for a swim.
Want to improve your sailing skills? Join one of our catamaran sailing courses and learn hands-on from experienced skippers.
