Greetings to all: trenching question,

[gwdixon]

Even though the soil is nice in Suisun Valley, pulling something 6 feet deep with a 40HP tractor just isn't going to be an option. It appears you already know that. Something dragged through the soil will likely just fill in and it sounds like you will want an open ditch.

I've seen large trenchers around here in orchard country that look like giant paddlewheels. They appear to be able to go down 6'. They are used to bury main water lines. However, they look to dig about a foot wide.

Google "large trencher" and look at the photos to see what is possible. Then go to a rental center and tell them what you want to do (or have done). A larger backhoe would do it also but it would take a while. North Vacaville has a couple of large equipment rental centers.

My advice is to go see Ron (owner) at Green Valley Tractor and ask what options are available. He has been in the area for many years. He lives and farms locally. Perhaps he has a connection.

Welcome to TBN. I'm just up the road from you in North Vacaville.

 

[Egon]

He's looking to plow the lines in. A one pass thing. At six feet it will probable be at the D-6 size for a non vibratory unit.

 

[CDN Farm Boy]

Lots of plows that big up here for installing field tile. But, most contractors don't want to look at a 6 acre job @ 30'-40' centers (6,000 ft) nevermind a 600 ft job.

Cost wise, digging it with a backhoe or excavator is likely the cheapest.

 

[jenkinsph]

I am in the middle of a similar project installing 2400ft of 4" pipe for geothermal heat and cooling. I am installing this 8' deep with the pipes on 24" centers. I recommend you use a backhoe to dig the line and lay the pipe in the trench and backfill. A good backhoe and operator can accomplish this job in one or two days most likely. You will need to make the ditch wide enough to make the connections at the end of the loops if you can't do that from the surface. Don't leave an open ditch for anyone to enter or fall into over night. Might want to consider a plastic safety fence or other safety measures.


I should add that a backhoe or mini excavator would both work for this job.

 

[texas42]

I suggest you think about an excavation rather than a trench. Hire a guy with a backhoe to dig a 6 foot deep excavation 15 feet x 100 feet. That way in the eyes of OSHA you have an excavation not a trench. You can safely go in the excavation lay out all your pipe, make all connections and pressure test then backfill.

 

[jenkinsph]

I suggest you think about an excavation rather than a trench. Hire a guy with a backhoe to dig a 6 foot deep excavation 15 feet x 100 feet. That way in the eyes of OSHA you have an excavation not a trench. You can safely go in the excavation lay out all your pipe, make all connections and pressure test then backfill.

When I started my geothermal project that is what I tried first. I used my box blade to dig down 4' deep in an area 55 ft x 110 ft. then dug down another 4' deep to install the pipe in the shallow trenches. For the second half of the project I am digging the full 8' depth and will not enter the trench, instead will use a piece of pipe to straighten the rolls of tubing. If that doesn't work I will excavate as before. I should know this week which works the best.

 

[Fallon]

A decent sized riding trencher will do it & they generally are 4-6" wide. My neighbor has a pole barn business & a riding trencher. I only needed 4', but he indicated he had a tail piece that could hit 6', barely if it was straight down.

Only being 4-6" wide means moving a LOT less material than a hoe of some sort. Unsurprisingly, a trencher is optimized for trenching, where a hoe is more versatile but slower & less efficient.

My 370' or so of trench was easily done in under a day & cost me $1,500. I may have been able to do it with a mini-ex in 2, probably 3 days ($300 a day rental + fuel). It would have looked a lot worse, moved a lot more dirt & tore up the yard a lot more. Not to mention have been a lit more work for me. Glad I paid the neighbor to do it, even though the mini-ex would have been fun for a bit.

 

[mike69440]

I think a ditch witch can only go 3-4 ft. +6' is going to be tough

 

[jimmysisson]

Trouble with a very narrow trench is you may not get good dirt contact to the pipe when you backfill. Isn't that what makes these systems work? A vibratory might be better in that regard.
Jim

 

[jenkinsph]

Trouble with a very narrow trench is you may not get good dirt contact to the pipe when you backfill. Isn't that what makes these systems work? A vibratory might be better in that regard.
Jim

That is a valid point I am concerned about. You do need to have good soil contact to get the thermal transfer. When I only had to dig 4' deep and 30 inches wide I ran my plate compactor over the pipe. My friend and I were discussing this yesterday. Excavating 4 ft. deep then digging 4 ft. with the backhoe may be the better route, just adds more work to the job.

For the OP with the smaller pipe and trench I wonder if using a power washer to help pack might do the trick? Weather permitting he could in a sense water pack the crack in a few lifts working to the surface.