With the countrywide drought and strict water restrictions in the Western Cape and other regions still fresh in our memory, several homeowners have resorted to – or are considering – installing shallow wells to access groundwater close to the surface. This water, if available in your area, is a great resource to supplement or even replace municipal water to irrigate your garden, or as an emergency water supply.
People have been digging wells all over the world for thousands of years and many of the best constructed wells are still in use today.
– What is a shallow well?
A shallow well is typically just a hole in the ground for water to seep into. It differs from a borehole in that it is much shallower and doesn’t attempt to tap into an underground aquifer. These wells can be created in a variety of different ways, depending on your soil type, from digging it with a shovel or excavator to drilling or ramming pipes into the ground. The cost of digging a shallow well is much less than drilling a deep borehole.
Water from these wells will typically have a lower level of total dissolved mineral solids compared to most boreholes, but shallow wells are more prone to bacterial contamination from above and the opening should always be covered for safety.
The sidewalls should also be lined with either plastic or metal piping to prevent it from collapsing.
– How do I get the water out?
Water can be extracted from a shallow well with a jet pump up to a depth of around 6 metres. The pipe going down the well should be as wide in diameter as possible to reduce friction and there must be a spring-loaded non-return valve at the bottom of the pipe to keep the pump primed. The water extracted by the jet pump can be stored in a water tank to use later, or it can be used directly to irrigate your garden.
The size of the jet pump you need will depend on the depth of your well, how fast it recharges, and how far you want to pump the water once it is above ground. The recharge rate of your well is the time it takes to refill with water after pumping all the water out. It is advisable to never let the inlet of your suction pipe hang right at the bottom of the well where it can suck in sand or debris, as this will very quickly wear the pump’s impeller down.
– How do I know if a well will work in my area?
The simplest way to know if a well will work in your area is to ask people in your community if they have a working well. Unfortunately, there is no fail-safe way of predicting exactly where you will find water when you start digging. It depends on the soil type, typography and even the rainfall of the recent past.
Pascali stocks a range of jet pumps suitable for shallow well applications and the technical team at Pascali is ready to answer any questions you may have.