4 in. x 10 ft. Corrugated Pipes Drain Pipe Perforated

It depends on the usage and the backfill and soil conditions. A Google search will list several resources. For instance, I used this without a sock to divert downspout water away from my house and to dry out a low area of the yard to a drainage ditch at the edge of the yard. Since the downspout water would keep it flushed out each time it rains, there's really no need for a sock. If properly installed with the holes down over top of 2" of washed pea gravel and then more pea gravel at least half way up the drainpipe, then most soils likely wouldn't need a sock even without getting flushed periodically. If the high end of the pipe is accessible to flush it out with a hose periodically, then a sock may not be needed either. Maybe you're draining water away from an artesian spring that flows heavy in the spring - that would keep the pipe flushed out as well. If not using pea gravel, and with no plan for flushing the pipe, or if the soil is mostly fine clay, then I would go with the type that has the sock pre-installed.

I haven't used it this way, but don't see an issue with that, as long as the circumference of the trunk is relatively-close to the diameter of the pipe you're using.

The drain pipe would be fine, but the installation is holding all the water. It needs to go down at the end also to drain properly.

The day I put mine in as drain system off the Calvert it hasn't rained yet, so time will tell

Sure,let me run out to the site and dig it up so I can measure it for you.

I am actually putting some three-quarter rock underneath my 3 inch tubing because it is perforated meaning that it has holes in it. If you are using solid pipe you don’t need to use any rock at least that’s what I’ve been told

The plastic material will last virtually forever once it's properly installed. The real problem is when will it fill up with accumulated dirt. So, if you bury it in 57 natural gravel stone and don't cover it over with topsoil it will last the longest without filling in. Dig the ditch 12" x 12", set the pitch to 1/4" per ft., put 3-4" gravel in the bottom, then cover to level ground. I have french drains that have lasted 25 years and still working.

Supply and demand... And convenience. You could buy smaller rolls and connect them, or pay a bit more for the convenience of a longer roll. If you want to see how the prices will affect the total job price, make sure to factor in the couplings (if you need them). Plumbing costs often go this way. Loot at some of the prices for PVC fittings. A coupling and a slip coupling are almost identical (the one just has an extra little ridge of plastic on the inside), yet the simpler one that is easier to make costs 3x the price because of the convenience when using it (demand). Its a dog eat dog world out there, stay safe ;)

HDPE does not leach chemicals. I used it for wicking beds. ~ Wicked Cool Elder Beds 2020

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