I have a free flowing artesian well, 70' deep that was drilled 9 years ago. It used to flow at about 7 US gpm. The water is for household usage and supplies a ground source heat pump for heating and cooling the house. The heat pump requires 6 gpm to operate. The discharge from the heat pump flows into a nearby creek along with the overflow from the well. We have been in the house for 7 years and until recently, we have had no problem with the well. About a month ago, the inhouse filter on the system filled with sand and cut off the water supply. The air-conditioning had been on for 4 days, the first time it was used to any extent all summer, due to a real hot spell we were encountering. With restricted household usage and no usage of the heat pump, the water cleared in 4 days. There was about a litre of sand in volume coming up the well per every 100 gallons of water. Sand was present not only in the supply line but at the well itself. The overflow of the well has reduced to 4.5 gpm. A week ago the air was on again for a day and sand came back three fold. It has subsided now to about 0.5 litres per 100 gal. I was told when the well was drilled, a 30' gusher resulted that took 16 hours to get under control. The well is located 8' from my house. I have talked to three well drilling companies, local people and 'experts' from our Provincial Government about the situation and I'm getting different opinions from all of them. Some of these are: pull the casing up 10' and install a screen; install a sand-point filter at the foot valve; don't dare touch the casing or cap the well unless you want to collapse the aquifer, drive the water up outside the casing and blow it out of the ground; clean it out and see what happens; pump the well waste at maximum rate for 24 - 48 hours to clear the sand (which I did for 3 hours and now have the startings of a beach on my front lawn and a jet pump that isn't worth too much at this point). As near as I can tell there is 2' to 4' of sand in the bottom of the casing. There are six other artesian wells on neighbouring properties within a mile radius that are operating just fine! Any opinions out there about what I should do? ... Barry, south-eastern Ontario, email: bhas@canada.com

-- Barry Has (bhas@canada.com), September 16, 2001

Answers

This is similiar to our problem w ehad with our well in VA. It was a dug well, however, it had enough water to supply our needs. the problem was after it rained it was clogged with sediments from the creek that fed the well. i thought a tthe time it was impossible as we were uphill a little from the creek. but our good frind and neighbor who drilled wells and did septics said that it can be deceiving, the gound below may not be the same as above, meaning it may not be uphill. So the problem worsened to the point w ehad red water from the red mud. Tried filters, etc no help so we were faced with the decision to drill a new well before we sold our farm. We dsiclosed this to the new buysers who did drill anew well. We had to get water from the neighbors for cooking and drinking and used the water for baths, cleaning, laundry, etc. We even had to ahul water from the creek for the goats at times when it was bad.

-- Bernice (geminigoats@yahoo.com), September 16, 2001.

Barry, unless there is something unusual about your well (and I defer to the local experts on this), it is generally a good idea to cap the well, so you're not using up the aquifer you, and everyone else who use it, are relying on for water.

Since I am not on your aquifer, I won't push it.

On the subject of the sand, here's one more option you could consider, though. Drill the well deeper--20 feet or more. Don't lower the pump (oops, don't lower the foot valve, in your case). This will give you one and one half gallons per foot you deepen the well, assuming you are using 6" casing, to serve as a sediment trap. Then you'll only have to clean out the well after the entire well below the foot valve has filled up.

By the way, if you cap off the well (and I'm not talking about not USING the well, merely putting a pressure cap on it), you'll accumulate a lot less sediment, since it won't be running all the time.

Good luck!

JOJ

-- jumpoff joe (jumpoff@ecoweb.net), September 17, 2001.

Bernice and JOJ, many thanks for your comments. There is a question of the integrity of the ground surrounding the well from 8' to it's final depth. A 4" 'O' pipe loop was installed around the casing at a depth of about 8' when the well was drilled to capture ground water around the well and discharge this at the same point as the well overflow. This originally flowed at about 1 to 2 gpm. It is now flowing in excess of 5 gpm. The thoughts from some of the experts is that water is pushing up from the aquifer around the well casing and causing sand to drop down to the lower entrance of the casing. If the well is capped, speculation is that pressure will increase around the casing and blow out water at ground level around the well. There is a possibility that the flow from the drainage loop around the well is coming from a separate shallow ground source though. I am afraid to dig around the well to determin this in case the water flow is in fact from the artesian aquifer and I let this very powerful genie out of the bottle. The foot valve is already suspended about 30' from the bottom of the well and there is visable sand in the overflow at the top of the well so I question whether drilling deeper would solve the problem. I too share your concerns about letting the well just overflow, but it does so into a creek along with the overflow from two other wells from neighbouring properties. This creek feeds some shallow wells, farm properties and environmentally protected wetlands along the line. Without it, during the drought we are experiencing, these properties could go without water. The sand that is comming from the well is extremely fine. Does anyone know if a screen placed at the bottom of the well or at the foot valve would work? My concerns are that it will quickly plug up while the flow is maintained. Thanks again for your comments.

... Barry

-- Barry Has (bhas@canada.com), September 17, 2001.

This is probably a very stupid question on my part, but I'll ask anyway (I wear many titles in my home . . .)

Would it be possible to push a garden hose to the bottom of your casing, then 'jet clean' the present line and hopefully push all of the sediment clear of the pipe? Might want to try as last resort, prior to re drilling / driving new well.

-- j.r. guerra (jrguerra@boultinghousesimpson.com), September 17, 2001.

Good point J.R. I'd probably have to get the local volinteer fire department to do this though, because if I did it with my own hose, I think the sand blown free would rise and plug the intake to the pump.

Does anyone know where I can find a wet-vac with a seventy foot lift?

...... Barry

-- Barry Has (bhas@canada.com), September 17, 2001.

I'm a little confused. Is the thirty feet of depth below the foot valve filled with sand?

If not, how does the sand get to the foot valve? Is the casing perforated, and the sand is coming through the perfs? If so, you could put a four inch liner down the hole, and only perforate it near the bottom.

Another possibility (and you've got a really challenging situation here, Barry!) is to capture the overflow in a pipe, if it's not already, and direct this overflow into a large storage tank. If the tank is sized adequately, the sand will settle out to the bottom of the tank, and you will install your pump in the tank instead of the well.

JOJ

-- jumpoff joe (jumpoff@ecoweb.net), September 17, 2001.

I'm a little confused. Is the thirty feet of depth below the foot valve filled with sand? Oops, upon rereading your post, you say only two or three feet has deposited there, apparently.

If not, how does the sand get to the foot valve? Is the casing perforated, and the sand is coming through the perfs? If so, you could put a four inch liner down the hole, and only perforate it near the bottom. This would likely avoid the sand, unless it is EXTREMELY fine.

A better solution, I think (and you've got a really challenging situation here, Barry!) is to capture the overflow in a pipe, if it's not already, and direct this overflow into a large storage tank. If the tank is sized adequately, the sand will settle out to the bottom of the tank, and you will install your pump in the tank instead of the well.

Also, if the tank is sized properly the 4.5 gpm which is currently overflowing the well, will give you way more water than you need, without pumping out of the well at all.

JOJ

-- jumpoff joe (jumpoff@ecoweb.net), September 17, 2001.

Per JOJ's last response: Sorry to confuse you. The well is 70' deep. When I drop a line in the well it bottoms out at 66'. There is therefor 4' of sand at the bottom of the casing. The 6" casing extends 28" above the ground with a 4" Tee for the overflow 19" above the ground. The house supply line enters the casing approx. 8' below ground level, where there is a 90 degree elbow with an extension line going down inside the casing approx. 20' to 30' and terminating with a foot valve. This puts the foot valve 30' to 40' above the sand bottom. To my knowledge the casing is not perforated unless it has rusted through,the supply line entry connection is corroded, or the casing was punched through at some point to limit the water flow at the top of the well. The sand is so fine, it is perculating up from the bottom of the well when more water is pumped than the well is normally overflowing. The sand flow, once started continues through the overflow for three days after heavy volume of water is pumped. The sand really stinks, so i am thinking it is coming from the aquifer.

Catching the overflow in a holding tank is a super idea. The water coming from the drainage pipe looping the well is cleaner than the well water and could probably be diverted to the holding tank too. This would give me a total flow of about 10 gpm. The well is located on a hill, so capturing the overflow should not be a problem. A tank, a back-hoe, a little creative plumming and away we go!

I am going to try cleaning out the bottom of the well first as I think this may be the least costly alternative (as soon as I figure out how this is done). Then I'll measure how long it takes to fill in.

Many, many thanks for your comments and creative thinking JOJ.

.... Barry

-- Barry Has (bhas@canada.com), September 17, 2001.

Glad to help Barry. I'd like to hear how it works out. Good luck!

JOJ

-- jumpoff joe (jumpoff@ecoweb.net), September 18, 2001.

A friend's artesian well stopped because of sand. He borrowed a large air compressor and put a hose down the well, pumped air down there for days. One day he came home and it was flowing again, sand all over the place. Perhaps you could put air hose down to get sand to get pushed up and out. Lower hose as sand comes out. Be careful not to drop hose down well. Might work. What do you think?

-- ed (edfrhes@aol.com), September 18, 2001.

Ed, the air hose down the well sounds like a good plan. I have been told several drilled wells (not the free-flowing type) around here have been cleaned by high pressure air injection.

I'll let you know how things turn out.

Thanks for your suggestion.

....... Barry

-- Barry Has (bhas@canada.com), September 19, 2001.

The well is well!

I attempted to put in a holding tank to collect the well run-off. It's a long, long story, but this turned out not to be a resolve to the situation. After several months of broken "I'll be there tomorrow" promises, the only well driller in the Province who would tackle restoration of my well, finally showed up. He bailed a little, drilled a little, and ended up cutting off the flow completely. The flow outside of the casing increased ten fold however which turned out to be the final clue to what had happened to the well in the first place. The driller simply pulled the casing up about an inch and a half and the water started flowing up where it should. The flow outside the casing reduced to a dribble. The theory is that when the well was originally drilled, the casing was driven down past the main aquifer to control the flow. Sediment build up and settling of the casing choked off the flow over time.

Many, many thanks to all of you who commented and provided suggestions on my original query ... especially JOJ.

Hope my comments above might help anyone in a similar situation.

Happy everything .......... Barry

-- Barry Has (bhas@canada.com), November 22, 2001.