How Does a Well Work?

The most frequent method of obtaining groundwater for home usage or drinking water is through a well. A well is essentially a hole in the ground surface with a pipe (or casing) leading to an underground aquifer. Water is drawn from the aquifer by a pump and distributed through the plumbing system.

Understanding how water wells work can help you control your water quality as well as know what water treatment system to use. It can also provide valuable insight into any potential repairs that occur.

How do wells work?

The water from your well is pumped into a storage tank, where it will be stored until you need it. When the system is turned on, water is drawn into the pump, which then pushes it to the surface and into a pressure tank.

Pumping water into a pressure tank causes the tank's air pressure to rise until it reaches a preset level of 40 to 60 psi. As you turn on a faucet in your home, the force of the tank's decreasing air pressure pushes water through your plumbing. When the air pressure drops to around 40 psi, the pump will turn back on and immediately begin to draw water into the storage tank.

Components of a Well Water System

Well Casing

The well casing is a tube-shaped structure that is installed in the well to keep the well opening open from the target groundwater to the surface. The casing, along with the grout, keeps dirt and excess water out of the well. This keeps contaminants from entering the well and contaminating the drinking water.

Well Cap

Well caps are also an important part of water systems. To keep dirt, insects, and small animals out of the well, well caps are installed on top of the casing. Aluminum or plastic are the most common materials for well tops. They have a vent to manage pressure while the well is being pumped.

Well Screen

To prevent too much silt from entering the well, well screens are installed at the bottom of the casing. Continuous slots, slotted pipes, and perforated pipes are the most common well screens.

Pressure Tank

Pressure tanks, as the name suggests, hold water under pressure. As water is pumped into the tank, it compresses the air in the tank until the pressure reaches a preset level — typically 40 to 60 pounds per square inch (psi) — at which point the pump automatically shuts off.

When a faucet is turned on, the air pressure in the tank forces water through the pipes until the pressure drops to a predetermined level — usually between 20 and 40 psi — at which point the pump restarts. A pressure switch activates and deactivates the pump at predetermined pressure levels, allowing the system to operate automatically.

Well Pump

A well pump is used to move water from a well into your home's plumbing. The correct size of the pump and pump motor is determined by the well diameter, well water level, number of plumbing fixtures, amount of water used, and peak water demand.

Pumps for water systems come in a variety of shapes and sizes. Some are only intended to extract water from a source. Others not only remove the water, but also force it through the remaining water system.

Types of Well Pumps

Submersible Pump

The submersible pump is possibly the most common type due to its flexibility. These pumps can be used in almost any well, no matter how shallow or deep it is.

Submersible pumps, as the name implies, are located underwater, deep within the well. These pumps are watertight, last long, and require little maintenance. Repairs, on the other hand, entail pulling the pump out of the well and up to the surface.

Centrifugal Pump

To generate suction, a centrifugal pump rotates an internal fan. Unlike other well pumps, centrifugal pumps are housed in mechanical housing next to the well rather than inside it, making maintenance easier.

One disadvantage of centrifugal pumps is that their suction is insufficient for use in deep wells. Centrifugal pumps are only an option if your well is less than 25 feet deep. The most affordable type of water pump for your water supply is the centrifugal well pump.

Jet Pumps

These high-tech pumps have the most power and can access water more quickly than other types of pumps. Jet pumps, like their submersible counterparts, can operate in wells of any depth.

The jet pump installation will be determined by whether it is "single-drop" or "double-drop." Single-drop models are located inside, either in your home or in an outbuilding, and are best suited for shallow wells. Split installation is required for double-drop models, which are best suited for deep wells. Even though the jet assembly is in the well, the motor must remain above ground.

While the initial costs of submersible pumps are frequently higher, the lower maintenance costs make them a better long-term investment.

Get the Well Pump Professional's Opinion

Need a Raleigh well and pump installation? Are you afraid your job is too big? Don’t worry, our team of qualified well and pump installers are up to the task. Call us today or fill out the form below to get a quote from our licensed water well pump professionals in Raleigh.