From time to time water boreholes might fail to produce the quantity or the quality of water they were once capable of; rather than abandon the borehole and incur the cost of a new one being drilled they can often be rehabilitated.
Our experienced engineering team have worked on a number of water borehole / borehole rehabilitation projects so often have a firm idea prior to any testing of what could be causing the problem and what will be the most economical route to take to bring the borehole back into optimum condition.
N.B. In some cases the borehole might not be clogged at all and simply the water table has dropped, meaning the solution is to drill deeper or drill an additional borehole to spread the load of abstraction across two, or in some cases, more boreholes.
What can cause a water borehole to need rehabilitation?
- Rusty slime on pipes
- Cloudy, rusty or dirty water
- Iron build up on pumps
- Deposits of distinct white powder or limescale
- Reduced flow of water / borehole yield
- Clogging of perforated / slotted casing over time with sediment or mineral deposits
- Clogging of fissures, pore spaces and crack in the natural aquifer from sediment or mineral deposit
- In some boreholes or boreholes which may have been badly constructed the borehole may have collapsed
What is the aim of borehole rehabilitation?
- The aim of any borehole rehabilitation project is to reclaim existing boreholes as opposed to simply abandoning them to drill a new one.
- This is often the most economic choice as there’s a cost involved of finding a new location, drilling and testing as borehole as the logistics of powering a pump and getting water to its required point of use.
- It’s worth remembering that a borehole was put in a particular spot for a good hydrogeological and pragmatic reason and in a lot of cases it makes much more sense to try rehabilitating a borehole than to drill a new one.
- Not only that, regular maintenance or remediation can improve the original yield and drawdown conditions as borehole as making the borehole more energy efficient especially with the additional introduction of modern technologies.
What methods are used to rehabilitate a borehole?
borehole rehabilitation is typically done using either:
- Chemical techniques i.e. using various types of chemical to dissolve the encrusting materials so they can be removed from the borehole.
- Physical techniques such as high pressure jetting to displace anything clogging the borehole.
If borehole rehabilitation is a success you can save money, restore lost capacity, increase the life expectancy of the pump, improve overall water quality, and extend the life expectancy of the borehole.