Water Well Problems, Remediation and Pump Replacement.
REPLACING GALVANISED STEEL WITH BORELINE RISER.
From time to time all water wells will require some form of maintenance. Although they usually run for many years with little or no maintenance, they will eventually need servicing.
Borehole-Driller assesses each water well individually and offers free advice to get your water well back to its optimum use.
The most common problems are that the pump ceases to operate,or water flow has reduced.
This can be caused by many different elements, from borehole design, riser pipe failure or corrosion, or simply that the borehole water pump has finally ceased to operate due to old age.
There are usually two types of Borehole design:
The first is a borehole which has been drilled using a steel casing. The steel casing is advanced to a depth which penetrates into geology that is no longer liable to cave in or collapse. The casing is then left in after the borehole has been completed, allowing the water to flow freely in to the borehole from the unlined aquifer. This method is usually advantageous if the borehole is particularly deep and reduces the cost of lining the borehole.
Most domestic supplies are not usually as deep and therefore benefit from cost savings using plastic well screen. The steel casing used to line the borehole whilst drilling is removed once the plastic well screen has been positioned. Plain casing is used for non permeable strata, and is grouted in to prevent contaminants from the surface entering the aquifer. The permeable layer is screened with slotted casing which allows optimum flow rates and provides stability within the well. The well screen can also be lined with geotextile wraps which prevent fine particles entering the borehole but still allow the water through.
Riser Pipes deliver the water from borehole pump to the surface. They are usually placed near the bottom of the borehole.
There are usually three types:
Galvanised steel riser pipe was often used in the past. Although it is strong, over a long period of time it is prone to rusting and scaling up within the riser. It is also time consuming to extract and install.
Plastic Water Pipe is now used in most wells, it is strong and obviously will not rust. It is light and therefore makes it easier to install and withdraw from the borehole.
High Tensile Polymer Pipe is preferable for very deep boreholes, or borehole using large diameter riser pipes. Installation and extraction times are massively reduced using this type of installation, and can even be performed without the use of a drilling rig or crane etc. The pipe is very similar to lay flat hose and is available in sizes from 1 inch to 8 inches in diameter. The pipe is so strong that it can support the weight of the pump and its water easily. It also has a very high burst pressure which makes it ideal for this application. Other advantages are that the internal part of the pipe is so smooth that algae etc cannot cling to the pipe which keeps the water clean. It also solves another problem when extracting the pump for service or repair. All pumps are fitted with a non return valve to protect the pump on start up. This means that although when you install the pump, you only have the weight of the pump and riser pipe to worry about. When you extract the pump you could also have the weight of 100 metres or more of water, this makes it extremely heavy to extract. The lower coupling on the riser pipe which is connected to the pump has a break off valve which allows the water to flow back in to the aquifer and makes it easier to withdraw. The break off valve can easily be replaced when lowering the pump back down after servicing.
Borehole Pump Replacement. We now use ZDS pumps fitted with a dry running protection microchip, and a 2 year no quibble guarantee direct from the Italian manufacturer. We offer these pumps at trade discount to our water well clients, you will not be able to beat our quote!!!
We give free advice on the best option for you, please feel free to contact us at anytime for a free no obligation quote.