PAM's three most common forms are dry granules, solid blocks (cubes), and emulsified liquids.
The application method of PAM chosen depends on the form of PAM selected. The use of dry granular PAM into irrigation water is facilitated by the use of an augured metering system and excellent mixing and thorough dissolving before the polyacrylamide reaches the irrigated furrows. PAM blocks (or cubes) are usually placed in wire baskets that need to be secured to the edge of the ditch to avoid washing of the blocks down the ditch. Liquid PAM can be metered directly from the container into the irrigation ditch, directly into the furrow, or through a pipe line or injector pump.
Dry granules of PAM polyacrylamide can be applied either by dissolving directly in the irrigation ditch before it hits the furrow, or applied directly in the furrow using what is known as the "patch method". In order for the PAM to dissolve properly in the irrigation ditch it must have proper agitation. Unlike sugar or salt which dissolve fairly quickly in water, granular PAM needs to be agitated thoroughly in order for it to dissolve. If not agitated, PAM globules form, and in time the globules can float down the furrow with little effect on the furrow erosion. A way to make sure the applied PAM is dissolved is to have a drop structure in the irrigation ditch to add turbulence to the water before it hits the furrow. Another tip to achieve desired dissolving is to place the applicator close to the point where the irrigation water first hits the ditch. In a concrete ditch, tins or boards will provide sufficient turbulence. In a earthen ditch a drop dam works nicely.