What Is a Wellpoint Pump? Key Components Of a Wellpoint Dewatering System Explained

Wellpoint pumps are specifically designed for dewatering applications in construction and civil engineering. They are used to lower groundwater levels and control water tables in shallow excavations. 

Vacuum-Assisted Wellpoint Pumps: These pumps create a vacuum to draw water from wellpoints and are effective for shallow dewatering applications. 

How deep is a wellpoint?

A wellpoint is typically used for shallow dewatering applications and is generally effective at depths of up to 5 to 7 meters (approximately 16 to 23 feet). This depth range makes wellpoints suitable for controlling groundwater levels in relatively shallow excavations, such as those found in foundation construction, trenching, and utility installations. 

The effectiveness of a wellpoint system can be influenced by various factors, including soil type, groundwater conditions, and the specific requirements of the dewatering project. For deeper dewatering needs, other methods such as deep wells or boreholes may be more appropriate. 

What is the difference between a borehole and a well point?

The terms “borehole” and “wellpoint” refer to different types of wells used for various purposes, including water extraction and dewatering. Here are the key differences between the two: 

Borehole

Depth: Boreholes can be drilled to significant depths, often ranging from tens to hundreds of meters, depending on the purpose and geological conditions. 

Diameter: Boreholes typically have a larger diameter compared to wellpoints, allowing for the installation of larger pumps and greater water extraction capacity. 

Purpose: Boreholes are primarily used for extracting groundwater for drinking water, irrigation, industrial use, and sometimes for geothermal energy extraction. They can also be used for environmental monitoring and sampling. 

Construction: Boreholes are drilled using specialized drilling rigs. The process involves drilling a hole into the ground, installing a casing to prevent collapse, and placing a pump at the bottom to lift water to the surface. 

Components: A borehole system usually includes a drilled hole, casing, screen (to filter out sediments), and a submersible pump. 

Wellpoint

Depth: Wellpoints are used for shallow dewatering applications, generally up to depths of around 5 to 7 meters (16 to 23 feet). They are not suitable for deeper groundwater control. 

Diameter: Wellpoints have a smaller diameter compared to boreholes, as they are designed for shallow and closely spaced installations. 

Purpose: Wellpoints are primarily used for dewatering construction sites, lowering groundwater levels, and controlling water tables to create dry and stable working conditions in excavations and trenches. 

Construction: Wellpoints are installed using a jetting process, where water is used to create a hole in the ground, and the wellpoint is then inserted. Multiple wellpoints are connected to a header pipe and a Wellpoint pump that creates a vacuum to draw water from the ground. 

Components: A wellpoint system includes small-diameter wellpoints, a header pipe, and a Wellpoint pump (often a centrifugal or piston pump). 

What is the difference between well point and deep well? 

Wellpoint System

Depth: Wellpoint systems are typically used for shallow dewatering applications, generally up to depths of around 5 to 7 meters (16 to 23 feet). They are not suitable for deeper groundwater control. 

Components: A wellpoint system consists of a series of small-diameter wells (wellpoints) connected to a header pipe and a Wellpoint pump. The wellpoints are usually spaced closely together around the perimeter of the excavation site. 

Installation: Wellpoints are installed using a jetting process, where water is used to create a hole in the ground, and the wellpoint is then inserted. The wellpoints are connected to a header pipe, which is connected to a vacuum pump that draws water from the ground. 

Applications: Wellpoint systems are ideal for dewatering in sandy or gravelly soils and are commonly used for shallow excavations, such as foundation construction, trenching, and utility installations. 

Deep Well System

Depth: Deep well systems are used for dewatering applications that require groundwater control at greater depths, typically beyond 7 meters (23 feet) and up to 30 meters (98 feet) or more. 

Components: A deep well system consists of larger-diameter wells equipped with submersible pumps. Each well operates independently, and the pumps are placed at the bottom of the wells to lift water to the surface. 

Installation: Deep wells are drilled using drilling rigs, and the submersible pumps are installed at the bottom of the wells. The wells are usually spaced farther apart compared to wellpoints. 

Applications: Deep well systems are suitable for dewatering in a variety of soil types, including cohesive soils like clay. They are commonly used for deeper excavations, such as large-scale construction projects, mining operations, and deep foundation work. 

What is a Wellpoint pump?

A Wellpoint pump is a type of dewatering pump used primarily in construction and civil engineering to lower groundwater levels and control water tables. This is essential for creating dry and stable working conditions in excavations, trenches, and other below-ground projects.