New well drilling, metal or PVC casing?

[falfrenzy]

I'm having a well drilled, approximate depth anticpated 350 ft. State requires a casing down to 80 feet, and I'm opting for a liner all the way to the bottom as the rock formations around are suspect (caves and various underground pockets).

Well driller has quoted a PVC casing, but I want this well to last a while (very long while). Should I request a steel liner instead?

 

[300UGUY]

I’d much rather have the pvc. It won’t wear out in your lifetime, and the less rust in the system, the better. And if you need to work on the pump, it isn’t rusted onto the casing.

 

[Billrog]

I would prefer PVC for the same reasons stated. And liner is a good idea.

 

[RNeumann]

They will do a metal casing down about 15-20’ (typically 6”) and then switch to pvc casing (typically 4”). A “good” well is cased all the way down to the bottom.

 

[hawkeye08]

My daughter/SIL just had a well drilled. Steel casing down to solid granite, then PVC lined to bottom. I expect the bottom sections to be slotted for the water to get in.. they got 1/5 gallons per minute at ~320ft, kept drilling, nothing more to 600', decided to go to 700' max, they hit 6.5 gallons at 698', felt great about enough water to avoid expensive cistern. Driller said he needed to go another 20' for room to set pump. They hit 60+ gallons per minute in that 20'. They have a expensive well, but plenty of water, cleared up quickly so expecting it to be good water.

 

[oosik]

What a good driller will do is run steel casing down until he is "bedded" into impervious soil (clay, silt or the like ) or into bedrock. If required he can also run drillers mud down to form a tight seal between the casing and the clay or bedrock. He can run steel casing all the way to the bottom or an appropriate plastic liner.

If the steel casing is terminated in solid bedrock - there is no reason what-so-ever to run a liner further down in the bedrock. Bedrock is ever so much stronger than steel or any type of plastic liner.

In solid bedrock you would only line to the bottom if a layer of sand, silt or clay was encountered and must be excluded from the water in the well.

 

[LittleBill21]

what does a pvc liner get you?

 

[300UGUY]

Bedrock around here is pretty far down. Most people have a pvc, 5 or 6 inch. The well might be 50 to 100 ft deep, but they hand the pumps above 50, usually. Water table in most of Michigan will come up to 15 or 20 ft. I have a friend here who has artisian well. His house is on a slab, so I expect the water table is pretty much ground level. My pump will do about 25 gpm. That's more than enough for my needs. Btw, these pvc wells are pvc all the way down.

 

[falfrenzy]

Biggest reason is to have the driller guarantee/warranty the well. Other reasons include rock shift/collapse down the well hole after the well has been drilled and pump set. Collapse could cut/damage the wiring leading to the pump, or the pump itself.

If there's an earthquake, all bets are off, no warranty coverage.

 

[Professor Marvel]

if it is cased all they way to the bottom how does the water get in?