With the recent water drama in Gauteng I started thinking more and more about using my borehole for potable water.
Background: I bought the house with the borehole. It is hooked up to a bunch of sprinkler systems and garden taps.
I have no idea what it is, how deep it is, what it yields or what the water quality is. I just know that it works, I see no residue (like iron) from it, the gardener have drunk from it and live to garden another day, the 900w pump is strong enough to run multiple sprinklers at a time and I’ve accidentally left it running overnight without any loss in pressure or water yield.
My guess is that I should first test the water quality - any suggestions on where and what I should test for?
Should I have the borehole itself tested?
Then next step would be to get a tank and a filtration system – I guess depending on the test results?
Take a water sample and send it to a lab for testing. Irrigation places may be able to tell you what labs to send it to. Here in the Cape you’d send it to Bemlab. This takes a few days and the price varies. For drinking water it’s about R1500 or so for the test. You will then get a full report of what is in the water, and whether it is suitable for human consumption.
Growing up on a farm, I seem to recall the big one is the nitrate content. That must be below a certain limit, Google says 10mg/liter, then it is suitable for human consumption. But basically you’re looking at all the important things here. Bacterial count/coliforms should be below some point, dissolved solids, hardness, Ph, etc etc. A whole heap of things. And DoC (dissolved organic carbon). That last one is what bacteria lives on, and it spoils filters.
Then once you know the water quality, you can decide on a treatment plan and if one is necessary. I don’t have the details for that. The last time I did this I only cared about making it sufficient for laundry use, and that meant I pretty much treated the water with ozone (which is somewhat crazy and expensive, but kills just about everything and oxidises your DOC) and that was that.
But my water was well water. It had lots of DOC and some iron too. Borehole water, coming from deeper down, tends to be much cleaner to start with.
Interesting fact. When I had my borehole water tested to see if its fit for human consumption, the company had a strict instruction regarding the collection of the sample. It had to be taken at night, wrapped and put in a box to prevent it from being exposed to sunlight. It also had to reach them within 24 hours after been taken. Luckily there were no traces of any dangerous elements and its been 3 years 7 months since we used the last drop from the muni.