Groundwater extraction - rainwater harvester, borehole, well

[martin69]

I have been looking into installing a rw harvesting system for toilets, washer and garden watering, but as the garden rises away from the house would have to bury the tank very low to get a fall on the pipes.

Last night I dug a test hole, and hit the water table 1300mm down (sand and gravel) - this after a very dry spring, and it occurred to me I need a well or borehole.

Has anyone any experience of this - I want something midway between an expensive 10m drilled hole and a bucket on a string - with a pump and filter etc?

I know there are issues about replenishment. I had wondered about using soakaway crates surrounded by geotextile (Aqualoc or Waterloc) to create an underground sump with a pipe going in to extract. Alternatively just dig deeper and install a wellhead.

Would it be better just to draw water as needed, or to have a header tank in order to overcome the replenishment problem.

Any advice, experience, contacts, where to buy would be much appreciated.

 

[Agile]

Sand and gravel will often have quite a high refill rate.

I would say that you need a storage tank with auto refill.

In my case I would use a tank filled from the rain downpipes as well as the ground water source.

My suggestion is that you dig a hole about 2m deep and use a submersible pump like a cheap Clarks or Screwfix etc to test the flow rate.

Toilet flushes are 6-7 li and the average is about 4-6 flushes per person per day. So about 100 li extraction per day would probably supply all your toilet needs.

Tony

 

[Onetap]

Look at drive point wells, basically malletting a steel tube into the ground. There are also numerous videos on Youtube about hand-drilled wells, using an auger to bore shallow wells. You can get an auger set for soil sampling. You wouldn't want to try to go much below 5 or 6m.

The shallow surface water will have all manner of organisms in it, but should be OK if you're only planning on using it for irrigation. Wells for drinking water should be bored through an impermeable strata, so the water has been filtered through the sub-soil layers above.

 

[Agile]

I wonder what extraction rate the OP discovered with the test well?

 

[ey143]

Hi martin69,
What was the end of result of all of this? I am thinking about either a borehole or a rainwater harvesting system myself for toilets and the garden as my house is quite big with an equally large garden and I am on a water meter.

Thanks.