Hydro Excavation - for residential Repiling

[FeverPitch]

Hi

Has anyone tried or used Hydro Excavation for digging holes for a retaining wall or repiling a house.

I spoke with a company today and they said they can excavate 10 holes ... 600mm diameter 1.5 metres deep in about 5.5 hours. A full days hire is $2300 based on a 10 hour day.
Their suction hose reach is between 60 -70 metres.

Seems like a quicker way than my only other alternative which is by hand.

Would love to hear of any past experiences. The soil is mainly clay and rock.

thanks Fever

[Meehole]

We had a hydro excavation truck outside our place a month ago taking the silt out of the open drain. I spoke to one of the contractors about getting them to suck the silt out from under our house as we have a high water table and the ground height under the house is lower than the ground outside. We were then thinking of putting a layer of aerated concrete on the ground as we end up with a swimming pool under there when we have a deluge.
I did not know they could drill pile holes for repiling and will look into that as it could be an option for us. Usually a repile is 40 to 50 piles 400 x 400 x 400 and digging takes at least a week.
If you go with this method I would be really interested to hear how it works out so please message me.
Why do you have to have 600 diameter holes 1.5 metres deep? Do you have enough room under there to place 2 metre long piles into the holes? Are they anchor piles? Food for thought for me anyway. :-)

[BDub]

We done a house on poles last year, we had a digger drilling the holes and it pissed down over the weekend before we got to concrete them in. We ended up getting a hydro vac to suck the silt and rock out. Worked well.

They also cut another 500mm out of one hole as the engineer wanted it deeper. They have one guy on a high pressure water blaster and another on a vacuume taking all the stuff that gets blasted away. This site some pretty hard rock on it which the digger would sometimes struggle on.

I also asked the guys about re-piling, they said they hate doing them under houses as all this shit blows back at them and they get covered.

I would happily pay $2300 if it meant I wasn’t digging under a house, nothing worse.

[Meehole]

$2300 to dig 6 holes is pretty expensive. Still have to put the piles in, level house, concrete and install fixings. Asked my husband about using them to dig holes and he said same thing, very messy and mud everywhere. I'm sure it has its place though.