Well casings serve several purposes in water wells. Together with the well screen it supports the borehole, protecting the well structure and pump. It also protects the ground water from contamination originating at the surface and in some cases plays an important role in the well construction process. There are four types of water well casings. They are classified according to function as surface casings, conductor casings, intermediate casing and pump housing casing. A well screen is a filtering device attached to the bottom of the well casing and serves as the water intake portion of the well. It is used to keep unconsolidated or semi-consolidated material from entering the well. The appropriate sizing of the screen slots are determined by the grain size of the material surrounding the bore hole. The correct size and spacing of the screen slots directly relates to the efficiency at which water can move into the well. A screen with relatively large slots may transmit a great amount of water, but may also allow sediment to enter the well. Conversely, a screen with smaller slots may restrict the entrance of sediment into the well, but also may restrict the flow of water hence screen should be selected accordingly. Bailer is like a length of pipe with a one-way valve in the bottom. The bailer is lowered into the well until it fills with water and sediment. It is then pulled to the surface and emptied. Water from the aquifer will then flow towards the well and bring in more drilling fluid. A bailer's up and down motion causes a surging action which will develop the area around the screen. The heavier and wider the bailer is, the better it will function because it will have more force to push water through the well screen.

Well Development Swabs are typically used in conjunction with gas-drive pumps simply by attaching the swab assembly to the threaded intake of the pump. This effectively increases the diameter of the pump to enable the user to produce the proper surging action within the open interval of the well.

Well drilling service is provided for drilling a hole in the ground for the extraction of a natural resource such as ground water, natural gas, or petroleum. This service is primarily engaged in drilling wells for oil and gas field operations.

Well examination is the independent assessment, or verification, on behalf of a well operator that wells are being designed and maintained in accordance with the appropriate standards. It covers all types of wells and operations including drilling, completion and production operations, through to abandonment.

Well log analysis is a general introduction to common openhole logging measurements, both wire line and MWD/LWD, and the interpretation of those measurements to determine the traditional analytical goals of porosity, fluid saturation, and lithology/mineralogy. It is arranged by the interpretation goals of the data, rather than by the underlying physics of the measurements.

Well log data is used extensively by the division of water to prepare ground water resource, pollution potential & detailed aquifer maps, and to assist with various ground water use conflict investigations. It is ideal to prepare bedrock topography, drift thickness, glacial and bedrock geologic maps, for coal and industrial minerals permitting, and oil and gas regulatory activities. In addition, it is used to provide ground water and well data for a variety of permitted or regulated activities including solid and hazardous waste disposal, underground storage tanks, wellhead protection and public water supply.