How close is too close to shore?

[bonkle]

Distances are incredibly hard to approximate but I'll try. I've taken the boat out a couple afternoons and anchored probably 800' from shore (a daunting swim in a calm lake). I wanted to stay on the safe side and have plenty of time to notice and react to an anchor failure. I went out on a buddy's boat last weekend and explored depths and distances along the shore. It was still 10' at 200' (short enough to have a swim race if you're reasonably in shape). Running aground on the beach is probably catastrophic. What do yall think about anchoring close enough to swim to shore?

There's also a spot on the bay side of Shell Island where the bottom slopes off incredibly quick. I haven't gone out to measure it yet, but it's around 5'@50'

 

[dlochner]

Too many variables to give a good answer. Is the wind offshore or onshore? How well is the anchor set? How steep is the bottom? How well do you swim? What shape are you in? What is the wind forecast to do? What is the bottom? Deep sand, mud, rock, rock with sand over it?

Every anchorage will be different and will change based on the conditions.

 

[Tally Ho]

I think you need to understand the tidal changes first.

I am on an inland ocean (Lake Michigan), so I don’t need to worry about tides. I can cozy up to the shore as close as I want as long as I have a few feet of water under my keel. I do consider the wind direction, so I don’t anchor close to shore in an off-shore breeze, and then wake up in the morning to an on-shore breeze moving me 50 feet closer to shore because I swung around on 25 feet of rode.

Other weather conditions should also be taken into consideration, as you have mentioned…in stormy weather, especially winds pushing you on shore, I would want more room between me and the shore In case the anchor drags.

The contour of the sea floor should also be taken into consideration….if it is a gentle rising sandy beach (my typical anchorage), I would be ok getting closer than having a hard rock ledge close to shore that I definitely want to stay far away from.

Sea floor anchoring conditions may also come into play…if you are in grass or other conditions that negatively impact anchor holding, give your self a little more room, just in case the anchor drags.

Greg

 

[bonkle]

Too many variables to give a good answer. Is the wind offshore or onshore? How well is the anchor set? How steep is the bottom? How well do you swim? What shape are you in? What is the wind forecast to do? What is the bottom? Deep sand, mud, rock, rock with sand over it?

Every anchorage will be different and will change based on the conditions.

I'm acually surprised to see a response suggesting that anchoring at a swimmable distance is not ridiculed. While learning about all this, these will be afternoon anchorages and I'll be on the boat ready to take evasive action... I'm super paranoid even at 800' out in 35' depth.
-Wind typically is onshore
-Anchor has never dragged (danforth 15-20lbs/1.5' flukes?)
-Swimming isn't an issue... wouldn't be able to catch a runaway boat tho.
-Bottom is sandy sand sand and gentle slope. Might be a little muckier on the bay side.
- It's the Gulf of Mexico, so there will be some rolling waves. Anything beyond that and it's no fun to anchor out there.

Here's a google aerial view of basically the entire coastline. Over time, that sand bar morphs between 50-150' from shore and 3-10' deep.

 

[Don S/V ILLusion]

I don’t understand this. My confusion derives from the implication you are afraid of being too far offshore to swim.
Do you wear a life vest? Do you have a dinghy? Do you have a radio? Do you have large bilge pumps?
My point being not to minimize your fear but to find ways you can obviate it.
To be blunt, maybe you picked the wrong hobby

 

[jdrutten]

...
-Bottom is sandy sand sand and gentle slope. Might be a little muckier on the bay side.

If you want to geek out over anchors, check out Steve Goodwin at SV Panope on youtube. Hours upon hours of anchor tests. He rates Danforths pretty high for clean sand and soft mud, but not so much for some other bottom types.

Scroll to the end for some general conclusions.

 

[bonkle]

I don’t understand this. My confusion derives from the implication you are afraid of being too far offshore to swim.
Do you wear a life vest? Do you have a dinghy? Do you have a radio? Do you have large bilge pumps?
My point being not to minimize your fear but to find ways you can obviate it.
To be blunt, maybe you picked the wrong hobby

Oh... no. I'm trying to figure out if I can take people to the beach on the boat... using it as a party barge. I'm trying to figure out if I can anchor close enough for it to be a leisurely dog-paddle to shore rather than a marathon.

 

[dlochner]

Oh... no. I'm trying to figure out if I can take people to the beach on the boat... using it as a party barge. I'm trying to figure out if I can anchor close enough for it to be a leisurely dog-paddle to shore rather than a marathon.

Buy a dinghy with a good sized motor.

 

[rgranger]

You said you anchor in a lake sometimes.... in a lake I don't think there is that much to worry about so long as you don't kiss the bottom... but if you are anchoring on an ocean shore, you need to think about two other things....

1) Tide! @Tally Ho already spoke to that one
2) Breaking swells... You don't want to be anyplace close to breaking swells at anchor....never!.... ever!

As far as party barge goes... if the seas are calm-ish and the bottom good, then go in a little close... drop anchor in 10+' of water... and take a second anchor out on a paddle board or kayak and set it so you have a fore and aft situation. So long as you are nearby to respond, you should be fine.

I'm a little like you when it comes to leaving the boat... here is a pic of a boat I had out in the NC outerbanks... I set two anchors in a V-pattern .... if the boat had drifted, me and the kids would have spent a few days on a barrier island mud flat.

We spent a week living on the boat... it was a blast.... but it was early May and we were the only crazy people out in the OBX. At night I would set three anchors in a triangular pattern. If the wind shifted I would always have two anchors holding.

 

[Don S/V ILLusion]

Oh... no. I'm trying to figure out if I can take people to the beach on the boat... using it as a party barge. I'm trying to figure out if I can anchor close enough for it to be a leisurely dog-paddle to shore rather than a marathon.

Got it!

I assume ”close enough” is a function of your guest’s swimming ability, water temperature, current, etc… more than distance.

 

[rgranger]

One more thing about swells.... if you have 10' of water under your keel but you are anchored in 5' swells, then at the bottom of the cycle you only have 5' of water under your keel. (and conversly 15' at the top of the swell)

 

[shemandr]

For the most part anchoring is for calm protected water. Yeah some cruisers get stuck in rolly anchorages and weather changes but that's an aberration. Especially if your plan is to orchestrate a party barge. You need to have a forecast for fair weather. Pick an anchorage that is in the lee of the land (In my opinion) and go ahead to anchor in 7 to 10 feet of water. If that's 10 yards off the beach that's fine as long as you keep an eye on the sky, an ear on the forecast and don't go too far from the boat.
More importantly you need to have a plan to escape sudden weather changes. A boatload of partied up people may no be in that plan.
By the way, I swim 700 to 800 yards every morning and it takes me upward of 40 minutes. I don't swim fast but that's too far from the boat.

 

[bonkle]

For the most part anchoring is for calm protected water. Yeah some cruisers get stuck in rolly anchorages and weather changes but that's an aberration.

We'll definitely have good weather for anchoring close. How do you check anchor set with diving down to look at it? I've just been dropping the anchor and if I don't seem to move, I figure it's good.

 

[jssailem]

My observations breaking down your key points.
I'm super paranoid even at 800' out in 35' depth.
Being concerned is a good start. Super Paranoid maybe a bit too much. Knowledge provides a great balance to paranoia.

1. It is not about the depth you drop the anchor it is about the depth within the radius of that point the boat will swing. You control that radius by how much chain/rode you let out. Let out 100 feet the boat (if the anchor is set and holds) should be able to swing in a circle limited to 100 ft from where you dropped the anchor. 35ft depth is a bit much. How deep does your keel sit below the boat? about 6 feet? On a calm day you could easily set anchor in 10 feet of water within that 100 ft radius to more shallow water.
2. Next know how anchor scope works. 3:1 in calm waters and your on board. 5:1 over night in calm to moderate conditions. 10:1 and maybe 2 anchors if riding out a storm and not near a lee shore. SET and ANCHOR ALARM.

-Wind typically is onshore
More caution is normal when being blown towards a shore line. A gentle breeze not so much. 30 knots of wind is considered a gale and a lee shore is not your friend. Pull up and move to a better/safer anchorage. I suspect you will not be swimming in a 30 knot storm.
-Anchor has never dragged (danforth 15-20lbs/1.5' flukes?)
Do you believe that the past is predictive of the future? I always anticipate the chance my anchor might drag. I set the anchor on adequate scope and set an alarm.
-Swimming isn't an issue... wouldn't be able to catch a runaway boat tho.
Would you be able to catch your boat is it would go in circles? Turn the rudder to one side and lock or tie it in place. Should the boat decide to go for a sail, it will be forced to do it in circles.
-Bottom is sandy sand sand and gentle slope. Might be a little muckier on the bay side.
All the better. Do you have a depth sounder? Scout out the place you want to anchor. Find a spot in 10 feet of water that you can place your anchor and gives you enough room to swing at anchor in a circle with out touching bottom. Do it a few times staying on board watching, say for lunch, to fill your knowledge bank with information as to how your boat will react in such conditions.
- It's the Gulf of Mexico, so there will be some rolling waves. Anything beyond that and it's no fun to anchor out there.
Ain't that the truth.

 

[shemandr]

Well diving on it in 10' is a lot easier than 35'.
Diving on an anchor is a whole other topic. I'm not aware of any quantified data for any anchor that correlates what you see with holding power. About all you can do is verify that it isn't fouled by the rode, that the flukes aren't jammed with a rock or whatever and that it's sitting on the bottom in the correct orientation. But if one fluke is dug in more than the other - what does that mean? How much the flukes are dug in - what does that mean?
We are advised to back down on the anchor to "Set" it. At least the flukes will dig in a bit but the set will be nowhere as deep as it would be after a gusty storm passes. And I've observed many boats pull their anchors off the bottom by backing down on it too much.
Normally when you lower the anchors and pay out some scope you can feel when it engages the bottom. That is when you can use some reverse engine to take slack out of the rode and set it. Then while you're swimming to shore have a look at it.

 

[rgranger]

I spent the night on the hook in a lake in my Hunter 26 one spring in 2019. I usually come into the cove and drop a “ lunch hook” over the side from the cockpit to stop the boat and then I make things tidy. My lunch hook is a small 5lb danford. I set my bigger anchor before I bunk down… but on this night The forecast (on the windy app) was for a dead calm night. So I didn’t bother setting my big anchor. A T-storm popped up during the night. It took me 45 min to get that little anchor up the next morning … and from the mud line on the rope rode…. I sunk 10’ of chain and another half foot of rope rode. I was lucky I had a mud bottom.

 

[jssailem]

So much of what you do and how you use your boat is based on where you sail.
I would not dive in the 50 degree water to inspect my anchor.
On the other hand, in the waters off Belize we did it all the time.
Then there was the night when at 0218 we awoke to a sudden squall that had swung our chartered boat and dislodged the Delta anchor pushing us towards the mangroves. Exciting times.

 

[MikeHoncho]

General thought process……if your considering the time you need to swim back to the boat if the anchor fails then my recommendation is reconsidering your ground tackle set up and choice of anchorages ( what the bottom is made up of). Now heavy onshore winds would be a consideration but your not going to swim in such a wind anyways.

 

[David in Sandusky]

In Marianne Cove in Baie Fine in the North Channel of Lake Huron, we anchored about 10 feet from the west shore. This cove has 360 degree protection from wind and waves. It has good depth right up to the shore. So like others there, we dropped our anchor in the mud toward the center of the cove, then backed up close to the shore in 10 feet of water, then we took a line ashore and tied off our stern to a tree on the shore. Then our companions in their Hunter 30 dropped their anchor to the right of ours, and backed up until we could tie their port side to our starboard side withe appropriate fenders between us. We spent two days there, hiking ashore, and #nug as two bugs in a rug!

Here is a photo by Julie Thorndycraft of the Great Lakes Cruising Club of a much larger boat tied to the east shore in a similar fashion. There are a number of similar anchorages in the North Channel, and the similar waters on the west coast of Sweden north of Gothenberg. There you can often find mooring rings installed in the granite shore to tie off your stern.

 

[jssailem]

Thinking about the OP's query, with no granite shore line to tie to, he could take a line to shore and sink an anchor into the beach. It would align his boat with the Gulf wave action and perhaps give him a little piece of mind.