Archimedes' screws, now called screw conveyors, are also used today primarily to propel dry bulk materials. However, if you do not have access to a generator pump and need a low-tech solution to raise water, it doesn't get much easier and low-tech than an Archimedes' screw. <ref>[http://www.ehow.com/how_8725014_build-handpowered-water-pump.html How to build and hand-powered water pump.] By Andrew Latham, eHow Contributor.</ref>
==Construction, operations and maintenance==
This small scale Archimedes Screw is a model to understand the concept of the water lifting device. The ones built by farmers are made of bamboo or other wood, usually. A working Archimedes Screw can be made using local (or cheap) materials in your region.
==Suitable conditions==
A major advantage of these pumps is variable pumping at constant speed, because the output (up to design capacity) is controlled by the sump level and equals the influent flow rate. The disadvantages are the inducement of turbulence, the release of odors and other volatile substances (if using for wastewater), and the relatively high initial cost (if using metal components, but not wooden). But when comparing costs with those of other types of pumps, consider the cost of the total system, including all piping, wet or dry wells, screens, fittings, valves, variable-speed controls, and other accessories as well as operating and maintenance costs. Note that operators like screw pumps because the good ones, when properly installed, are so trouble-free.<ref> [http://uotechnology.edu.iq/dep-building/LECTURE/sanitary%20&%20environmental/third_class/Water%20Networks%20and%20Equipment/D-pumps-3rd%20Class.pdf Pumps and Pumping Stations, 3rd Class. By Dr. Sataa Al-Bayati. University of Technology - Iraq.<ref/>
====Materials====
* Handle
* PVC tube
* Hose pipe
====Construct it====
# Measure the distance from the water source to where you want to pump it. Cut the PVC tube to measure.
# Tape a handle to the top of the PVC hose. The handle is optional, but it will help you pump faster. The longer the handle, the easier it will be to turn the pipe.
# Tape one end of the hose to the bottom of the PVC tube with the duct tape. Allow the hose to overlap the tube by 1 inch. Be generous with the masking tape to ensure the hose does not move when you start pumping.
# Twist the hose around the PVC pipe in a corkscrew pattern. Tape the hose to the top of the PVC pipe. Again allow for an inch or two overlap and cut the hose. This will allow the water to drain out of the hose as you turn the PVC pipe.
This simple screw pump can be viewed as a series of ramps around a central axle. As you turn the PVC pipe, you carry the water in small lifts from one ramp to another until it pours out of the top. It is much easier to pump water with a conveyor screw than to lift the water vertically, just like walking along a winding mountain path is easier than climbing straight up.
