As we all know, a water pump is a convenient device, which comes handy in many household applications. It is essentially used to transfer large amounts of water from point A to point B. The uses of a good water pump are versatile: it is incredibly practical and easy to use for a number of residential, commercial, construction and agricultural settings. A carefully selected and quality pump may be ideal for handling such tasks as draining water from a basement or a shallow flooded area, draining or refilling your swimming pool, pond or simply a bath tub, disseminating fertilizers or pesticides, and many other arduous tasks.

The assortment of water pumps is extremely large, hence, while shopping for a durable and a reliable one, you need to take into account the purpose you are purchasing a water pump for. Acquiring a better understanding of how a water pump works, will help you to reduce the operational costs, maximize the durability of the pump and the overall performance of the system.

Types of Water Pumps

Generally, we distinguish between two major types of water pumps: electric-powered water pumps and gas-powered water pumps. Electric-powered water pumps are an excellent solution for indoor use. You can easily plug them into a standard power outlet.

On the other hand, gas-powered water pumps are used in large-scale applications as you may spot them either at construction sites or at farms. Their engines are more powerful, and they are capable of moving up to 750 gallons of water per minute. Naturally, if you face a problem of moving large amounts of water, such as from a flooded basement, or for irrigation purposes, you should definitely opt for gas-powered water pumps. Another perk of gas-powered water pumps is their speed: if you need the work to be done fast, this type of a water pump will rescue you. Nevertheless, gas-powered pumps are mostly intended for outdoor use, as they produce carbon monoxide emissions.

In their turn, gas-powered water pumps fall into three categories: dewatering, trash and PTO water pumps. Each of these pumps has its specific application. Dewatering pumps are the commonly used water pumps to transfer large amounts of water. Trash pumps are more suitable for moving water with debris, trash, thick chunks or other solids up to two inches in diameter. Last but not least, PTO pumps are widely applied in the agricultural sector as they require a tractor for their operation. PTO pumps receive power from the drive-shat of the tractor’s engine, hence they are powerful and years of quality use are guaranteed.

So, how does a water pump work exactly?

While we do appreciate the useful nature and multiple applications of a water pump, most of us are still unaware of how exactly this machine functions. We should dive into the world of water pumps not only for shaping a better understanding of their structure and operation but also for making much more careful selection and securing better maintenance. Being able to understand technical specifications of water pumps will prevent you from feeling lost in such a wide assortment if you are obtaining an electric water pump for the first time.

According to their structure, water pumps are classified as centrifugal and positive displacement pumps. Centrifugal pumps are the most widespread type, with positive displacement pumps being limited to industrial purposes.

Centrifugal Pump Working principle

What is an Impeller and How it Works

A centrifugal pump is powered by an impeller. An impeller basically works like a miniature merry-go-round, that is, it spins very fast and this creates a centrifugal force, which compresses the water against outside of the blade. In a sense, impellers are just blades extending from a disk.

While spinning, the high speed of the impeller forces the water to go from inside to outside. The quantity of the water to be pumped also depends on how fast the impeller spins: the faster it spins, the more water is pumped. The impeller spins in a single direction, hence, the water is accordingly pushed out in just one way. Even if the pump is submerged, it still functions similarly.

The Motor

Most of the small electric water pumps are equipped with a compact DC motor attached to the impeller. DC motor is any rotary electrical machine converting direct current electrical energy into mechanical energy. Once the motor is on, it creates a magnetic field around it making the rotor spin. When the rotor is in action, it causes the impeller to spin, hence, powers the pump.

How to select the right water pump?

Now that we have developed a basic understanding of how a water pump works, we should tackle the criteria for a successful selection of a water pump. There is no “easy way” in selecting a durable and a reliable water pump. If anyone tries to advise you a water pump without first establishing the necessary specifications, such as the water flow, GPM or other essential requirements, then they are simply guessing or advertising the product. Here are some tips, which may come handy while selecting the right water pump:

  • Pay attention to the water flow and water pressure specifications
  • Give preference to water pumps with convenient outlets and long cable cords for the sake of easy installation and more options for connection
  • Keep in mind that lightweight aluminum castings allow mobility of the pump
  • Closely examine the material of a water pump: pumps should preferably be made of weather-resistant material.

How to Insure that Your Pump Works Properly

A good maintenance is the first and foremost guarantee for the longevity of a water pump, its smooth and durable performance.  A properly and carefully maintained water pump will serve at its best for long years. Thus, given the chance, try to purchase one from a servicing dealer, in case, if you need assistance, you may refer to repair centers.

Secondly, understanding how a water pump functions is essential in order to independently run the water pump correctly and make sure it functions efficiently. Time spent to maintain your water pump is actually a lifetime investment in the performance and value of a water pump. It is advisable to regularly check your pump for leakages, fissure or wear and tear.  For instance, if you are aware of the technical specifications, you will easily notice changes in the pump flow, overheating, excessive noises or clogging. All those instances indirectly indicate that you have to be knowledgable about the model you have purchased in order to perform better maintenance.


Water pumps are great addition to our lives, as they facilitate a great variety of household, industrial and agricultural tasks. However, the assortment of water pumps in the market is so versatile and abundant that choosing the right pump suitable for your needs is challenging.

For the sake of making the right decision, it is advisable to get a basic idea of the structure of water pumps. Not only does this information come handy when you select one, but is also very useful during the actual exploitation of a water pump. Water pumps are ever in motion, hence, timely and appropriate maintenance is what ensures smooth and long-term operation. If you are equipped with practical knowledge you are all set to independently choose and operate a water pump and troubleshoot any malfunctions.


  • Thanks for writing this awesome article. I’m a long time reader but I’ve never been compelled to leave a comment.
    I subscribed to your blog and shared this on my Facebook.
    Thanks again for a great post!

  • And modern electronic pumps have the same principle of operation? And is it really possible to subordinate the pump yourself if it breaks?

  • The article is written quite conspicuously and in general terms. However, there is enough information to understand the principle of operation of the water pump.

  • Thank you so much for your article about water pumps and how they work. I like how you said that it is important to choose a pump that is made out of weather-resistant materials. My dad wants to buy a water pump, so I will make sure that he chooses one that is made out of high-quality materials.

  • I like that you suggested examining the material of the water pump because it must be made of weather-resistant material. This is something that I will remember in order to save money on replacements in the long run. I am interested in buying a water pump which I could use to easily drain and refill our swimming pool at home and for irrigation purposes. Thanks for sharing this.

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