Whether you’re dropping the hook for a few hours of lounging in the sun or planning to spend the night at-anchor, having reliable equipment and a consistent process for anchoring is key to enjoying peace of mind in an anchorage. That’s why we’ve put together these eight tips for anchoring your boat safely, so you can enjoy some stress-free time on the water.
1. Use the Proper Anchor
There are several different types of anchors, and they all perform differently depending on the type of seabed floor they’re setting in. For example, a Danforth or fluke anchor performs better in sand or mud than it does on a seabed floor that has dense seaweed where a plow style anchor might be better. So it’s always important to know what type of conditions you’ll typically be anchoring in and to equip your boat with the best style of anchor for those conditions. In general, local expertise from professionals or fellow avid boaters in your area is the best resource for knowing what the seabed floor is like, and what types of anchors work best there.
It’s also important to have the right size of anchor for your boat to make sure it can dig in and hold regardless of the conditions. While there are some commonly-used guidelines about anchor size – one pound of anchor per foot of boat length, for example – there really isn’t a universal formula given the different styles and technological advancements from different manufacturers. The best way to size the anchor is to follow the manufacturer’s recommendations, and to size up if in doubt.
2. Use the Proper Anchor Rode
Almost as important as having the proper anchor, is choosing the right anchor rode for your boat and anchoring habits. The most common form of rode is to combine some chain and some rope, with more chain being used on larger boats that anchor in deeper water and more rope for smaller boats which only anchor on day trips to the beach. In general terms, more chain is always more secure, as the weight of the chain helps the anchor set and hold at the correct angle. But obviously more chain can be more difficult to store and adds more weight to the boat. For an in-depth look at choosing the right anchor rode for your boat, continue reading here.
3. Know the Depth of the Water and Use Enough Scope
Besides using improper equipment for the conditions or boat, the most common cause of boaters dragging their anchor and not setting properly is due to not letting out enough of their rode, known as “scope”. The reason scope is so important has to do with the angle of the rode in relation to the seabed floor as it connects the boat and anchor. Anchors are designed to set and hold most effectively when pulled along the bottom by a force parallel to the seabed floor. Therefore, the steeper the angle between the anchor and the boat, the more likely it is that the boat bouncing in waves or a gust of wind will pull the anchor up. This is also the reason why having chain at the anchor end of the rode helps the anchor to set and hold better because the weight of the chain helps to decrease the angle of the rode in relation to the seabed.
A general rule for scope is to have a 7:1 ratio of rode to the depth of the water. For example, if you’re anchoring in 10 feet of water you should let out at least 70-feet of rode to ensure a secure set and hold of the anchor. Like with anchor size, letting out more scope is always more secure. Of course, if you’re anchoring up at a beach for an hour and not leaving the boat so you can monitor if you do begin to drag, you can get away with less, but keeping a 7:1 ratio in mind as a minimum is a good practice.
To use the right amount of scope, you need to know the depth of the water, which any depth-sounder or up-to-date chart can help with, as well as how much anchor rode you’ve deployed. Keeping track of the amount of rode deployed can be as simple as painting the chain different colors in pre-measured increments, using colored chain markers at those same increments, or for a more precise measurement, installing a chain-counter with your windlass is a great option.
4. Give Yourself Enough Space
The most common mistake that boaters make in anchorages is getting too close to other boats. Once you’ve calculated the scope you can use that length, add it to the length of your boat, then think of that like a radius of a circle with your anchor being the center point. Then you just need make sure there are no other boats within that distance from the point where you lower your anchor. The longer you plan to rest at anchor the more space you’ll need to allow, as wind shifts or changes in current can make the boat swing in an entirely different direction from the original position. If you’re planning to anchor for just an hour or two and there is no forecasted change in the weather, you can anchor closer to boats upwind of you without worrying about swinging 180-degrees around. When in doubt, allowing more space is always better for everyone’s peace of mind.
5. Know the Weather & Tides
Knowing the tidal conditions and weather forecast tie directly into knowing how much scope to use and how much space for swinging on your anchor you’ll need. If you’re in an area where tides only range 2’-3’, knowing the tide won’t have a major affect on the scope you’ll need. But if you’re anchoring at low tide and it might come up 5-feet or more in the time you’re anchored, the 7:1 scope calculation could be a difference of 35’ or more at high tide versus low tide. Similarly, if the wind and current conditions are going to be steady while you’re anchored you can focus more on having enough space downwind of the anchor. If the forecast is for changing conditions, you should focus on having a full circle of space around the anchor.