2” Threaded Deep Well Pump Basics

Use the 2" Threaded Deep Well Pump System if your well specs meets this scenario:

Static Water Level:250′ or less
Electric Submersible Pump Installed:No
Well Casing Outside Diameter:2″ NPT


The Bison Pumps 2” Threaded Deep Well Pump System is a Stand-Alone system that functions the same as the Side-By-Side (Side-By-Side Deep Well Pump Basics) but is not installed in the same well casing as your electric submersible pump system due to a lack of available space inside the casing. It is a Freeze Proof pump system that can deliver you with Pressurized Backup Water when used in conjunction with the Pressurizing System. This provides you with water inside your home accessible to any water feature such as a toilet or sink. It can lift water from 250 feet deep using the standard handle or up to 300 feet with the addition of the Heavy Duty Pump Head option. It is recommended when the well casing is 2” NPT and there is not an electric submersible pump system installed in the well.

2″ Threaded Deep Well Pump Connection

Bison Pumps’ 2” Threaded Deep Well Pump System is designed to be used with a driven well or other 2” NPT well casing situations. Unlike the other Well Pump Adapters, the 2” Threaded Well Adapter is not welded onto the body of the pump head. This adapter threads onto the 1 1/4” water inlet instead. During installation it is threaded onto the 2” NPT well casing.

Well Pump Adapter

This well pump adapter would be used when the well casing is 2” NPT and there is NOT an electric submersible pump installed in the well. If there is another pump installed in the casing, then a Bison Pump Deep Well System cannot be used. With only 2” of inside casing available, only one system at a time can fit into the well casing. In these situations, the only options are to either remove the electric submersible pump from the well casing or drill a separate well just for the Bison Pumps system.

One alternative to the Bison Deep Well Pump System in this situation is to install a shallow well pump onto the 2” NPT well casing. In this situation you still cannot have an electric submersible pump installed. If your static water level is less than 25’ and the pump would not be subject to freezing, then you could use our shallow well Model 1900 Stainless Steel Pitcher Pump.

Drop Pipe and Rod

Each Bison Pumps Stand Alone 2” Threaded Deep Well Pump System comes with enough eight (8) foot sections of Drop Pipe and Rod to reach approximately 20 feet below the static water level. This depth allows for fluctuations in the water table and ensures that the cylinder will be below the water surface.

This pump system would have to use 1” NPT drop pipe and rod to accommodate the fact that the inside diameter of the well casing is less than 2” and the bell on the 1 1/4” pipe exceeds 2”. This requires reducing the pump head water inlet from 1 1/4” NPT to 1” NPT. This reducing bushing is welded to the inside of the water inlet. Notice in the photo above that the water inlet pipe is smaller than the pump body.

Note that the deeper the static water level is, the more drop pipe and rod will be required. This directly impacts the cost and design of the system. This is why a fixed cost for a pump system cannot be provided. Each pump system is unique to the customer’s well specifics.


One 1 1/2” cylinder is included in a Stand Alone 2” Threaded Deep Well Pump System. In a Lift Pump system, like the Stand Alone, the actual “pump” is the cylinder. This is the device that creates the vacuum to draw water into the water inlet and then uses its piston assembly to lift the water up the drop pipe. When installing the 2” Threaded Deep Well Pump System, the only cylinder that would fit inside the well casing is the 1 1/2” diameter cylinder. It outputs a gallon of water for roughly every 32 strokes. By comparison, if you were able to utilize the Model 1900 shallow well pump, it would provide a gallon of water every seven (7) strokes.