Want to build a boat ramp and need advice..Help

[poncho-pwr]

I just bought a place at the lake and the previous owner had just gotten through extending part of the driveway in concrete 210ft down to the waters edge with the intent of building his own boat ramp. Well, to make a long story short I bought the place from the guys family after he passed away a few months ago and now I would like to finish the job on the boat ramp. The lake bottom slopes downward at a perfect angle for a good ramp but the bottom is too soft to use like it is. We could use it and have a couple times but it takes four wheel drive and leaving big ruts that we would have to back over every time we went in and out with the trailer. Could any of you give me some ideas on the best way to go about doing this? The driveway is concrete and 10ft wide all the way to the waters edge and I would like to extend the ramp from there to about 30ft or so into the lake. Any ideas?

[TRUMP TIGHT]

I just bought a place at the lake and the previous owner had just gotten through extending part of the driveway in concrete 210ft down to the waters edge with the intent of building his own boat ramp. Well, to make a long story short I bought the place from the guys family after he passed away a few months ago and now I would like to finish the job on the boat ramp. The lake bottom slopes downward at a perfect angle for a good ramp but the bottom is too soft to use like it is. We could use it and have a couple times but it takes four wheel drive and leaving big ruts that we would have to back over every time we went in and out with the trailer. Could any of you give me some ideas on the best way to go about doing this? The driveway is concrete and 10ft wide all the way to the waters edge and I would like to extend the ramp from there to about 30ft or so into the lake. Any ideas?
A cheap quick fix for now would be lay some carpet down and stake it in.
Congrats on the house!

[YeLLowBoaT]

1st make sure its legal to do.
If its a resivor your really lucky. you just have to wait till they let some water out( it will save you $$$$$, then grade and pore...) How much are you looking to spend? You could go from abotu a $100 for some sheets of ply to in the $10000s to pore a slab under water. It all really depends on what your location is like and how much you want to spend.

[poncho-pwr]

If I could do it nicely for around $5000 or less I would be happy. Yes, I have checked with the authorities and it's okay to build the ramp.

[YeLLowBoaT]

Well I would start with a good layer of aggregate. Since anything else you do will need a decent foundtation. That in itself might work for you. 5k is not alot of cash when you are talking about specialized concrete. Even if you keep the thickness down your still looking at ~ 5 yds.
The "BEST" thing you could do is wait til the water level drops and do it right.
I know of other things that you could do, but with out knowing the legistics of the area Its hard to point you in the right direction.

[Red Horse]

Compaction and subgrade are going to make or break you. I am not sure how to do it when the water is up, but then the water is down you will need to compact the soil and then add sub grade to get a good foudation. With something like this that is prone to settle and drift I would put in some pylons. Basically holes about 18 inches in diameter about 2-3 foot down poured at the same time. Make the pad a min of 6 inches thick. I am not sure if tying in the existing pad is good or not. I have done thousands of yards or crete, but never underwater. Good luck

[Old Guy]

Been there...done that. We live on a lake (had the place almost 50 years), and always needed a boat ramp. Lake bottom is muck. Many ruts in yard pulling boats out.
Dad was a cement contractor and had a dump truck. We eventually got a load of washed stone and dumped it at the waters edge. I thought maybe it would displace the muck and provide something to not get stuck on. It did seem to work, but he retired and got rid of the truck.
A few years later, I decided to put in a concrete ramp. A friend had a portable, small (360 gpm) irrigation pump that I borrowed for the job. I built a 3 sided box, using 3/4" plywood, about 6' wider and 6' longer than the ramp. We had to put plastic sheeting (the thin stuff you use like a tarp) on the outside of the box and hold it in place with sand bags. The water wanted to wash in under the box. I used a 5 gallon bucket buried in the lake bottom for the pump intake (so I could pump all the water out).
We then built a form and called the redi-mix truck. It worked quite well. The far end of the ramp needs to be at least a foot BELOW the lake bottom. If not, there will always be a hole at the end of the ramp.
I was about 35 and Dad was near 70 at the time. It was hard work.
The ramp worked perfectly until we enlarged the house making the ramp inaccessible. We removed the ramp and extended the seawall.
Good luck
Oh......just a note: Boat ramps are EXTREMELY DANGEROUS!! They get a coating of slime from below the water line to a couple feet above the water line. When it gets wet, it's very much like wet ice. Anyone stepping on it, WILL FALL DOWN. Several fell on ours (that's why it's gone now) over the years. My son has a shoulder that was permanently damaged on it 30 years ago.
I think if I was going to do it again, I would avoid concrete. People think they're gonna be careful. They fall and get hurt.
old

[msc5195]

I watched a local set preformed slabs 6'x10'x8" via Large Crane. I believe he set 7 of them. The slabs were reinforced with wire and the had pad eyes on each end. the pad eyes had stainless cable threaded through them with a turn buckle to hold them together. This worked out great but may be over your 5000 budget.
Also look HERE (http://www.shawneesteps.com/boatramps.htm)

[Mandelon]

I can think of a few different ways, but I've never done it. I am a contractor, but only one who wishes he lived on a lake....
Ideally, wait for the water level to go down.
Form and pour, but pour thick at the bottom edge, and I'd lay it over a foot of gravel too. Use a real rough finish, ridges are what they have at most ramps around here. They hurt bare feet, but aren't ever slippery.
If the level won't go down you would need to build forms and pump out the water as described above. A sump and pump make sense, and the forms would need to be high enough to keep most boat wakes from washing over their edges. You'd basically be making your own levee....Make them bigger than the ramp so you can work on it with a couple of feet to spare around the edges......
Prefab slabs....you could pour these your self on site and set them with a crane or similar lifting device. Heck, you could rig up an engine hoist or something and set smaller slabs your self. They'd have to connect together somehow....interlocking edges......it could work
May be easier just to call in someone who does it for a living though.....

[msc5195]

Prefab slabs....you could pour these your self on site and set them with a crane or similar lifting device. Heck, you could rig up an engine hoist or something and set smaller slabs your self. They'd have to connect together somehow....interlocking edges......it could work
May be easier just to call in someone who does it for a living though.....
I agree fab up and pour you some 2' x 10' x 8" salbs with stainless eye bolts sticking out of each end then set them in place via rented boom truck. Lace the eyes together with stainless cable and a turn buckle. A couple cases of beer and a few steaks on the grille and you should be able to get your friends over to help set them in place.