The borehole yield test measures how many litres per hour the borehole delivers and forms part of the COC (certificate of compliance). Banks and insurers require it to attach value to the borehole. When selling or buying a property with a borehole, a COC (stating the installation conforms to SANS 10299-4:2003) is required to transfer the property. It is also essential when selecting your borehole pump since mismatching the yield and pump could be disastrous.
We make sure you got what you paid for
Once we have successfully drilled, intercepted the ground water, and your borehole has been cased and sealed, we need to determine how much water it can consistently produce per hour. This is commonly called a borehole yield test and we do this once the underground water table has been stabilised.
Using our highly calibrated machinery we measure the hourly flow (borehole yield) of the borehole over a 4–5-hour period. Once completed, the yield test serves as a certificate of compliance that can be given to your bank or insurance company as proof that the borehole installation meets the SANS 10299-4:2003 specifications.
Why do you need a yield test?
The law requires that you provide a borehole yield test when selling a property with a borehole on it that delivers 300L or more of water per hour. Furthermore, the yield test shows the maximum water the borehole can yield per hour. If you do not know what the hourly yield is you could miss-match the borehole yield and the size of the pump. This can cause the borehole to either run dry or collapse. Having a yield test is therefore essential.
Why do you need a yield test?
The law requires that you provide a borehole yield test when selling a property with a borehole on it that delivers 300L or more of water per hour. Furthermore, the yield test shows the maximum water the borehole can yield per hour. If you do not know what the hourly yield is you could miss-match the borehole yield and the size of the pump. This can cause the borehole to either run dry or collapse. Having a yield test is therefore essential.
How much will my borehole yield?
If you want to go completely off-grid you will need a yield that is in excess of 1500 litres per hour. This assumes no connection to a municipal point. For general residential use where there is municipal supply, 300 litres and up is most common.
The main factors that influence your borehole yield is not only the size of the required borehole or depth, but a proper and professional borehole survey being conducted from the beginning, to establish the best possible subterranean water source.
Farmers generally prefer to access a water source that is fed by more than one vein or aquafer, or two or more underground rivers, since it dramatically increases yield. These types of hydrologic features are often found very deep underground and can be fairly costly to drill to this depth.