We're always learning something new about country living. Today, it was that our 440 foot new well, just three months old, can quickly accumulate 60 feet of silt.
It surprised even our well driller, Troy, who said that in his experience he's only had a couple of ten inch wells manifest this odd behavior. Unfortunately, it was our well and the next one he drilled.
When Oregon Pump came by a few weeks ago to install a pump in the new well, they found that a probe couldn't get anywhere near the bottom. Since the well has a liner all the way down, that surprised us.
The slots in the liner where water flows in are only 1/8 of an inch wide. We couldn't understand how so much debris could get into the liner from the sides of the well, especially since we hadn't been using it, so no water was moving up and down.
When it got to about 380 feet, we hit pay dirt. Or rather, dirt that we'd paid to have removed, but was still in the well. This wasn't Troy's fault -- just one of those things that happens in well drilling, and thankfully it's fixable.
It was slimy rather than rocky or dirty. Tiny particles were evident in it. Troy explained that this is probably what happened:
After he enlarged the well to ten inches (we started with a six inch well), he let the water settle for a day. Then he put the liner in -- 20 foot lengths of perforated PVC pipe, glued together.
He had no problem getting the liner all the way down to the bottom, so the well obviously hadn't silted up right away.
Troy figures that the large ten inch well must have contained a lot of fine particles that were still floating around in the water (about 1800 gallons worth) even after a day of settling. Water was both inside and outside of the liner.
So most of the silt, or sediment, was already inside the liner, and simply settled to the bottom eventually. Likely there also is sediment outside the liner also, between the pipe and and the walls of the well.
Troy is going to rent a sediment pump, take out the liner, and then remove the silt. He explained how the pump works, but I'm incapable of re-stating the mildly erotic details of the suction process.
This should restore our well to close to 440 feet deep. Certainly much closer than we are now. The pump will be installed 20 or so feet from the bottom, in case some silting reoccurs.
I wanted to tell our story in case someone else has a similar problem, and finds this blog post via a Google search. This amount of silting isn't common in a new well. Doing my own Googling, I couldn't find any obvious references to what happened to us.
But not many residential wells are ten inches in diameter. There's three times as much water in a ten inch well as in a six inch well, so seemingly there also would be three times as many floating particles.
It's still difficult to picture how those particles could end up silting up 60 feet of a six inch liner. Yet the camera showed that this is what we've got.
(If you are a city dweller who reads this post, out of boredom or some other reason, be thankful that all you need to do is turn a faucet and water comes out. We love living in the country, but at times, like today, a condo with a couple of potted plants on the deck sounds pretty appealing.)