Building a dock

[snowwolfe]

Wife wants a small dock that she can walk out on when she feeds the fish in our 1 acre pond. Plus the dock would add a little cover for the fish. My thoughts are to use 30 gallon white plastic barrels that are sealed and build a 2x6 enclosure around them with 2x4 slats across the top. I will put two barrels side by side, then add 2 more in front, and then another 2. This will give me two rows of 3 barrels. The dock will end up being about 14 feet long and 3.5 feet wide.

All suggestions are appreciated as I will not build it until March or April.

[skeeter2]

Put poles in. Using the barrels sounds like it would be rather bouncy when walked on. Even if you have a liner, just set treated 4x4 as poles on the bottom.

[sparky45]

Don't forget a Lawn Chair or two when you're finished.

[MUSTANG]

I would consider making it wider. The 40 inch width precludes two people on the dock, particularly difficult fr one to pass the other/turn around with two on the dock. Additionally, if in the future if kids or others want to fish from the dock, a 40" width would make it difficult for the same reasons.

[waksupi]

The barrels will work fine. Like has been said, make it wider for stability and space. I'd go 6' minimum, and would prefer 8'.

[blackthorn]

The barrels will work fine. I used them under a dock but I filled them with Styrofoam packing chips (in case of leaks).

[OS OK]

How much water will the drums displace? Unless you submerge them completely, you can't figure 30 gallons each...submerged 1/2 way would be a 15 gallon displacement per drum...then, that times aprox. 8.3 lbs/gallon would suggest that one 30 gallon drum will support about 125 pounds.
That times 6 drums will support about 747 pounds.
747 minus the weight of the drums and the lumber will give you what the dock will support in people and chairs etc.

Build it much wider or it will sink significantly one one side and dump the occupant of the dock. When they stand to one side the weight is reduced to almost 1/2 of capacity because it bears down on only 1/2 of the barrels.
What your thinking will be a good learning curve for you...just assemble it with screws so you can reconfigure when your done.

Make sure you make a video when your unsuspecting wife strolls out on it to try it out! . . . :bigsmyl2:

[Pipefitter]

Decking boards across the top will reduce the weight versus 2X4's. For stability you could mount a couple 2" half round pipe straps on each side and drive a section of 1 1/2" pipe through the straps into the bottom of the pond. This will allow the dock to move up and down according to the water level and the amount of weight on the dock.

[farmerjim]

I built mine with 2 10 inch round treated poles pounded in with a long reach backhoe. 8 feet wide. poles were 12 feet out. Side boards were 2x12 rough pressure treated 18 feet long. 6x6 pressure treated poles were hand pounded into the pond at the ends of the 18 foot side boards. 2x10 PT was put down the center of the boards on 2x10 that were attached to the 2x12's. the deck is 2x4 PT with 1/4 in between boards. This was put in 17 years ago and is still in use with no maintenance required.
It cost about $800 back then.

[snowwolfe]

Keep the comments coming. Already learned to make it wider.

[Gewehr-Guy]

Pull the bungs, cut the bottoms out of the barrels, weld a thick walled pipe to a disc blade, insert in the barrels and sink them in place. Then partially fill with rock till they feel solid, then drill and bolt on the dock subframe.

[Duckiller]

Snowolfe you have moved. Will your pond ever freeze? Does the water elevation vary much? The floating dock takes care of a varying water elevation and allows it to be removed if pond starts to freeze. Posts make the dock more stable. Enjoy the pond. Wife should consider a small canoe or kayak.

[quilbilly]

You never mentioned how deep the pond is or how steep the sides are. Does the pond go up/down very much for irrigation drawdown? Most of the plastic barrels I see are 3-1/2 to four feet tall so if partially filled with rocks and flooded could be used as a 3-1/2 foot high base for the wider walkway which won't be bouncy. Fish would like that better too as a hiding spot with the vertical "pillars. Treated 2x12's could be attached to the barrels as floor joists to raise the walkway even higher off the water and it would be a very stable walkway on which you could put up a low rail.

[snowwolfe]

Banks are pretty steep and center is 23 feet deep. Try not to over think this. It will only be used on occasion by one of us to walk out and toss fish food. Elevation can change by up to 2 feet if we get another drought. Plus one day I want to make the dam higher so the height of the water could increase by 18 inches or so. I don't want a permanent dock. It will float and be mobile if I need to move it.

[iomskp]

I have seen one made with 44 gallon blue drums out to the middle of a dam at the end in the middle of the dam they went two wide and made a sit down area with a table and chairs.

[Ballistics in Scotland]

The barrels will work fine. Like has bldeen said, make it wider for stability and space. I'd go 6' minimum, and would prefer 8'.

Yes, that sounds about right. At forty inches it wouldn't be stable enough for even one person to walk on safely. It doesn't have to overturn a person, even with a lot of baggage in his arm, to tip him into the water. You can learn a bit by a scale model in indoor weather.

I'd prefer not to rely on driven piles as part of the structure, for the will rot. Piles to secure a floating dock to are much better, for you can much more easily replace hem. If the barrels are round, the stability would be greatest if the dock floats with them immersed just below the middle, no matter whether the woodwork alone or part-filling them with water will do that. The increased depth of flotation per pound of weight will be least when it is immersing the greatest possible volume of barrel.

[MyFlatline]

6' wide is ideal, with the barrels side by side on the outer edges, with end to end no more than 2' apart. Make it so you can change the barrels from the top, they will leak and collapse. If you can find the encapsulated foam dock floats, they will last your children's lifetime. Question being, how much do you want to spend.

[skeettx]

http://www.discountdocksupply.com/Dock-Flotation-Eagle-Float-Size-24x36-2436.htm?_vsrefdom=adwords&gclid=EAIaIQobChMI5e3E_diF2AIVirbACh0S6AeyEAQYASAB EgL9vfD_BwE

[Down South]

Banks are pretty steep and center is 23 feet deep. Try not to over think this. It will only be used on occasion by one of us to walk out and toss fish food. Elevation can change by up to 2 feet if we get another drought. Plus one day I want to make the dam higher so the height of the water could increase by 18 inches or so. I don't want a permanent dock. It will float and be mobile if I need to move it.

My Son In Law builds docks for a living. I had him build my floating boat house that holds my 26' party boat and bass boat on lifts plus the jet ski that I never use. I used commercial flotation which ain't cheap. I think that I have about 10K in flotation alone.

Just to let you know, the EPA might soon outlaw barrels on some lakes if they haven't already. Some folks use barrels that harsh chemicals or oil were stored in and without proper flushing could cause pollution if they leak. But since it is a pond on your property, you shouldn't have to worry about that.


Anyway, for the dock that you want to build, the barrels will work fine. If I were you, I'd pull the bungs that were used, clean them well and put a bead of silicon rubber around the seal and reinstall them. I've seen a lot of drums used for flotation leak around the bung after they were unsealed.
I'd consider going 6' to 8' wide for stability. You can still use your 6 drum idea, just spread them out a little wider.

Have you thought about how you will anchor your dock to the bank? You mentioned the pond level fluctuated 18"? I'd think about driving two heavy posts close to the bank, fix some type of donut rings to the dock that the posts will go through so the dock will float level no matter what the pond level is. I'd use a gang plank from the bank to the dock which would compensate for water level changes.

Hope this helps, Sam

[GhostHawk]

Up here in the north country most all water freezes 3-4 feet deep. Come spring a wind will shove that mass north one day and south the next wrecking anything fixed.

Docks almost all come with wheels up here, plus a piece of pipe on each side in a bracket with a disc blade welded on the bottom. Loosen the jam nut, lift it clear, tighten it up and roll the dock out.

Down there you may be able to leave it in year round. But I would still plan on a couple of supports to lock it into place.

I've helped build two big docks, most 1 1/4 square tubing for the top rails, 1" for the bottom and 1/2 rod for x bracing. Wheels on 2 big threaded rod adjustments so they can be raised, lowered. One was fairly long, had a second set of wheels and a hinge point for walking over the shore.

Tried several things for decking. Worst was 3/4 green treated plywood with indoor/outdoor carpet.

Best was the formed planks they use for decks, mix of sawdust and plastic it appears to be. Those took the humidity well, did not warp, twist, or rot.

If it was me I would use 2x6's not 2x4's, more comfortable for the feet. Leave 1.5 inch gaps between. And I would cut them to length, paint them on all sides, assemble, and paint again.

[Hogtamer]

Make sure it has a ladder into the water in case someone falls in.

[Hogtamer]

Make sure it has a ladder into the water in case someone falls in.

[Menner]

SnowWolfe
I am kinda simple minded so I would approach it this way
6x30x8.3=1494 lbs of buoyancy 9=2241 lbs so if you load 1494 on 6 barrels you would be floating but right at the surface of the water so I would work on a 50% basis I would want about half of the barrel out of the water and I would want the wood of the dock to stay out of the water.
Having said all that, from what I gather this is a private pond with no tidal rise or fall and no motor boats only seasonal water table changes that will be slow changes so and I would assume nobody would be venturing out on the dock in the middle of a storm so waves should not be a problem
I would assume you will use treated lumber (that mess is heavy, a calculator I found said treated 2x4x6' is 10.5lbs 2x4x8' is 14lbs 2x6x8' is 22lbs) and width is your friend for stability I would make it at least 6' wide and probably 8'wide. At 6'x14' you are going to have approx. 700lbs in lumber (Treated) At 8'x14' Approx. 900lbs
going wider will not cost you that much more and would be well worth the stability just keep the barrels as far out board as you can for maximum pontoon effect, I would consider 9 barrels and being fresh water a couple pieces of 1 1/2" galvanized pipe driven into the bottom and a couple of 2" pipe straps would hold it in place ( put caps on the top of the pipes or the hornets will love you)
Just my thoughts we have built a couple using 55gal Drums and they are a lot more stable if the barrels are close to 1/2 submerged.
Tony

[snowwolfe]

Make sure it has a ladder into the water in case someone falls in.

If anyone falls in they can walk swim, paddle, or pull them self along the dock to the shore and walk out, lol.

[Ballistics in Scotland]

If it was me I would use 2x6's not 2x4's, more comfortable for the feet. Leave 1.5 inch gaps between. And I would cut them to length, paint them on all sides, assemble, and paint again.

Most of Ghosthawk's advice is real horse's mouth stuff, but I'd leave smaller gaps between the boards. It's more comfortable on bare feet, a lot more things fall through 1½in. gaps than ½in. (and in the life of a dock it will be a key someday), and the latter would be just as good for ventilation to reduce rot.

I don't know about sawdust and plastic, but if you use wood tar and fine gravel, not too sharp, it is about the best non-slip surface you can get. I used to walk on a pedestrians-only pier treated that way, perhaps before the First World War, and it didn't change in decades. With a small closed pond with fish, you should do that some way from the water. The same goes for real creosote if you have protected from it, which is far superior to the modern rotproofing compounds.

You would probably find more uses for it when you've got it. Kids would love to detach it and use it as a raft, and on an acre if they can swim forty yards, they're never all at sea.

Purpose-made plastic floats should outlast wood. So they are worth setting up a followed search for,. with e-mail notifications, on eBay. If someone has a few of those going spare, he has to reconcile himself to letting them go cheap.

[country gent]

I would also consider putting the center row of barrels slightly lower than the outer rows. 2"-3" should be enough. This way the center supports more of the weight and the outers provide more stability to the dock. Also rubber pad the barrels were bands are used to attach to the dock or the bands will cut thru the barrels from motion over time. Securing it to the bank of the pond may or may not be needed. A way to maintain load with water level raising and dropping over the summer is an advantage also.

[Ballistics in Scotland]

Or just make the frame grip the barrels tightly, with all the wood above water if possible. They aren't going to dive to get out of the frame.

[shooterg]

If you're near any big lakes where used boats show up, at times you can pick up old pontoon boats for not much. Just fit boards on top of the pontoon base , or use as is ! . We had one on a 7 ac. park pond as a maintenance platform but could use it for a portable dock.