Large Bubbling Boulder

[Raj Venugopal]

Here's a question I don't think has been posted re waterfeatures...

Anyone do a bubbling boulder(s) as part of a pondless (or ponded) waterfeature? By bubbling, I mean knocking out a 1 and 3/4" core and feeding pump forced water through the column.

Thanks

[Lanelle]

Yes ???

[Stonehenge]

I know Matt Kulp's done that: landscapingpennsylvania.com

[natural12]

Did this feature a while back. Drilled a hole thru a pumice rock. It is very soft so drilling was easy.

[Raj Venugopal]

I'll be likely using sandstone, a little harder I suspect but still soft. Trying to figure out how to drill it. Any helpful construction tricks? Like, how do you (that have done it) run your water supply through the core? Do the hookup with the stone suspended, or drop it onto a supply line? Do you lay on a grate, or directly on the built up aggregate in the basin? What if the boulder is large, i.e. over a ton? How do you prevent the basin sinking from the weight of the featured stone? What do I need to watch out for? I know the mechanics of water features, and while this kind of thing seems pretty simple, has a few tricky aspects.

[Lanelle]

I had a granite/stone fabrication company drill the core hole for me.
If you are using a preformed basin, put cinderblocks directly under the feature boulder, leaving space to run the tubing. Don't remember how I secured the tubing on that one.
On others that I got predrilled, we used threaded plumbing fittings secured with plumbers putty on the bottom of the stones. Put down a compacted base or concrete pad under the basin so it will stay level if you are using a really large heavy boulder.

[Raj Venugopal]

I had a granite/stone fabrication company drill the core hole for me.
If you are using a preformed basin, put cinderblocks directly under the feature boulder, leaving space to run the tubing. Don't remember how I secured the tubing on that one.
On others that I got predrilled, we used threaded plumbing fittings secured with plumbers putty on the bottom of the stones. Put down a compacted base or concrete pad under the basin so it will stay level if you are using a really large heavy boulder.

I like the idea of usng threaded plumbing fittings. As for cinder blocks, what about mounting the boulder on several cinder blocks that sit on a 3x3 foot patio slab, all buried by the clean rock filling the water catchment area? That way the cinder block/ slabs would be entirely covered but on a broader base... Keeps all the bottom fittings accessible.

[natural12]

Yes I would use 3 piers or 3 set of concrete block. You can feed the tubing up the hole you drilled and seal the outside with foam or silicone.

The tricky part is maintaining access to the pump. I suppose you could use a pump vault or waterfall well that is used for the pondless water features. I think I would even use a few pond matrix boxes (they look like milk crates). This would allow for more water and less gravel. The homeowner would appreciate not having to fill the water feature as often. Then fill the area with stone. The top of the pump vault will be just below the top of the gravel.

You will need a core bit to drill your hole and powerful drill. I would ask your local stone supplier if they could drill it.

Some sandstone can be very hard so be prepared.

Good luck.

[eastern1]

Drilling it was the toughest part really, here we placed the rock on a bed of large river stone, access is not a problem this way. Finished product of boulder and project shown

[DanP]

I may be wrong but it looks like eastern is using a diamond coring bit. We use 3' hammerdrill bits that just rips through boulders. Rent a hilti/bosch hammerdrill for $50... but the bit might set you back $200-$300 to buy. Don't worry though, it'll usually last 10 to 15 good size boulders. Sandstone was always very easy for us... usually about 5 to 10 minutes to go through 2 feet or so.
Like mentioned above, use cinderblocks/retaining wall blocks to prop up the rock. We use a woodshims, rock strap and skid-steer forks to position the boulder. The hammerdrill bit we use is 1" diameter, so we can just jam a 3/4" poly pipe in and it stays tight (do it before you set the rock precariously on the blocks). But silicone if you want to. The best thing we've found for a pump container is probably a sump-pump box that you drill holes into. $20 and it's deep enough to ensure you pump won't run dry and seize up if the homeowner forgets to add water in the hot months. But take out the lid if it's a screw top kind because the gravel will get stuck and it'll be a PITA to access the pump. I'd suggest flagstone. Backfill the precariously set boulder with gravel until it's sturdy and safe. The rock will eventually sink the cinderblocks down a little, but the gravel will then evenly support the entire boulder. If your winter involves freezing, put on a quick-disconnect coupler (a union) so that the home-owner can pull the pump out as he/she pleases. I'm on vacation right now, I'll post some pics when I get home.
But I'd really suggest going the hammerdrill route.

Dan

[eastern1]

That rock only took about 20mins to core thru. I have another one to do this week and will keep tabs on the time involved just for fun.

[4seasons]

The one we did, we hammer drilled through. IT busts the bottom out is the only downfall, but you cant see it. Also since its sandstone, don't let it sit in water. it will soak it up and start breaking in the winter months.

I went to the local rental place and we drilled the boulder on site, cost a couple bucks.

[Keith N]

[QUOTE= Also since its sandstone, don't let it sit in water. it will soak it up and start breaking in the winter months.[/QUOTE]

Depends on the sandstone. Local Missouri SS is soft and will do that, but Arkansas SS is pretty dense stuff. It better be for $250 a ton.:mellow:

[Raj Venugopal]

Thanks for the responses guys, and the pics. Nice job there by the way. Home Depot has a corded hammer drill with a 21" shaft diamond bit that gives 17" of cutting (minus the shaft in the chuck). My concern is not having enough cutting depth with that so I'll keep searching....

[eastern1]

Thanks for the responses guys, and the pics. Nice job there by the way. Home Depot has a corded hammer drill with a 21" shaft diamond bit that gives 17" of cutting (minus the shaft in the chuck). My concern is not having enough cutting depth with that so I'll keep searching....

Drilled thru a rock this aft. rock was 21" deep. Just add an extension to the core bit.

[Mag Marconis]

Help! I am new to this, but have been trying to figure out a way to build a waterfall over some boulders that an excavator just put in my yard. The project was not as I had showed him in a picture before he started and I ended up with a six foot boulder wall. Had I known this was the result I would of had him put a liner under the boulders. Is there any other way anyone can think of that I can now do a 1 drop waterfall down six feet into a pondless pond without a liner. The boulders are much to big to move at this point and the waterfall would make the whole project complete. In addition to ending up with a wall I was not expecting it cost me three times as much as he had originally quoted me. If I could just do a water feature it would then make the wall worth the price.

I live in PA

Thanks for any help or suggestions or can give me.

Mag

[Green Man Envy]

I did a project last year that involved drilling through about 15' of stone (many small bits of fieldstone found on site, the largest was 12" deep). I quickly learned that the 1/2" bits on a regular hammer drill just couldn't cut it. Although the test at my house on my local stone worked fine, it took hours on site just to get through less than an inch of rock, and that was spread across a number of different pieces.

I wound up upgrading to an SDS-Max rotary hammer and made it through all 15' (and then some, due to occasional breakage) in less time than it took to get through that first inch with the hammer drill.

In the process, I also determined that Irwin bits were the only ones that did the job without self-destructing.

I only had to bore a hole for some supporting rebar, so I didn't have to worry about connecting up water flow.

At some point, I'll be working on a boulder-based waterfall in my own yard, although, since I'm going for natural crumbling slate formation kind of look, I may get around any ~ or at least some ~ drilling issues by using smaller bits of slate to build the "boulder".

[Raj Venugopal]

I'm strongly considering using an artificial stone product (see weathered edge limestone armour rock) by Stonelink at Stone-Link Online Catalogue 2010 (http://stone-link.com).

shouldn't be too hard to drill through 18" of that stuff with an SDS roto Bosch 1 3/4" hammer drill.

[NCSULandscaper]

this was a fake stone bubbler we did years and years back that was decent, but at the time the budget wasnt there for a real stone but it still looks good to this day

[Raj Venugopal]

Do you recall what size pump you used???

[Raj Venugopal]

On this as well, thanks guys for your feedback. I ran 1.5" tubing using both ABS and PVC flex. Used a threaded orifice on the discharge that could be screwed shut for winter drainage- there's a fourth nozzle capped shut to which the h/o can screw on a fitting to drain it. Most importantly, the h/o's were happy... Now we just have to get it finished. That rock, btw, is over 9 feet wide and 3 feet deep, 1.5 feet high. Way bigger than it looks.

[4seasons]

I like it Raj. What size pump did you use? 2-3k gph?

[Stonehenge]

Very cool, Raj.

And yeah, I HATE that about big stones - they always end up looking like toys when they're photographed. Do you have any other progress pics? I'd love to see some of that.

[Raj Venugopal]

I like it Raj. What size pump did you use? 2-3k gph?

We used a 3000 GPH pump, swapped it for a 4000, bought a 5000 just in case, repurchased the 3000 and that's what we ended up with. Reduced the 1.5" to .5" and aerated with some drill holes around the orifice. Quite the process.

[Raj Venugopal]

Very cool, Raj.

And yeah, I HATE that about big stones - they always end up looking like toys when they're photographed. Do you have any other progress pics? I'd love to see some of that.

I'll be posting some before and afters on our website once the building season is done and I have a bit of time to actually do some marketing! I definitely have some good ones though. I'll even try to put up a short video.