Total coliform present — spring

Hello!

Moving towards purchasing an off-grid property, which I mentioned in a previous post. The primary cabin is fed by a spring/dug well, I believe about 8 ft. deep, which gravity feeds to the building.

Just got back the results of a water test, which show total coliform present (but E. coli not present). Two things to note:

1) The shallow well is new and I believe lined with concrete well tiles, but currently covered only by a board weighed down by some rocks. When I looked in it the other day, a couple insects and some vegetation were clearly visible on the surface of the water.

2) The property has experienced heavy rains over the last couple weeks—the well was dry two weeks ago, but now has maybe 5 ft of water in it.

My *guess* is that the lack of a tight lid, plus the heavy rains, might lead to the bacterial contamination. A previous water test the current owner shared from last fall shows no coliform bacteria present. So my hope would be that installing a concrete cap, and disinfecting the well, would take care of this.

I'm interested in anyone's input on the situation. I should also note, the cabin is off-grid, and greywater from the cabin (including a spring overflow) just flows to a ditch alongside the structure. I'm therefore concerned about using bleach in the well, as chlorine seems to be the standard for decontamination in this situation, but it's just going to flow straight onto the ground.

Any input appreciated!

I would still buy the property, but you are drinking water from the surface level water table, which is only 3ft below or so, you need a better spring head/well that doesn't allow sunlight or air or insects to get in. Once that is done you should be golden.

You also have to think about the future too, what happens when 5yrs from now someone uphill from you start pouring pesticides, septic water, and fertilizer and chemicals from his garage junk yard shop into the ground/surface level water table?

You can always run a UV filter on the water when it hits your house, or ferment the water that you drink with water kefir like they used to do in the old days.

Can you rely on rainfall?

Have a look at this benefits of rainfall

Thanks for the replies.

S Bengi:  Not super, super concerned about significant development above given the location, but definitely something I'm aware of.

John Daley:  Definitely interested in looking into rainfall as a backup system.

I am hopeful that adding a proper cap will be sufficient. The well is pretty nice and new and hopeful the quality stays high. This said, any tips on how one might disinfect this sort of well, even as a one-time thing when getting started?

Standard advice is to use chlorine bleach, which I'm wary off, among other reasons because as I mention grey water / spring overflow just drain out into a ditch along the driveway. Is iodine reasonable // would it be less harmful? Other thoughts very welcome.

Consider a quality ceramic filtration system.  Have that water tested to see how effective it is.

Thank you, but I think the water is probably OK. A previous test result showed no coliform bacteria present, and as I said, it's got a sort of makeshift cap right now and there were just heavy rains.

Because of the most recent test to be safe I think disinfecting it might be worthwhile, so I'm wondering if there's any effective way to do so without bleach, basically. But adjacent thoughts are welcome.

I think it's okay to use medicine, once in a while even though it has side effect and similarly it's okay to use chlorine seeing as how it will only be a very rare event.

As for an alternative to chlorine, maybe some food grade hydrogen peroxide would be good, esp one that is super concentrated. Or maybe you can rent a food grade ozone machine (they use them to wash vegetables/produce) and use it to add ozone to the water in the well, killing the microbes in it.