Test PB Collection: FTE

Sand media filters Photo: L. SchwanklSuspended particulate materials in irrigation water may be inorganic (sand, silt, and clay), organic (algae, bacteria, plant debris, fish, insect larvae, etc.) or any other floating or suspended materials.

Storage reservoir with organic contamination Photo: L. SchwanklBiological growths in drip lines and emitters can be a serious problem when the irrigation water contains organic sediments, iron, or hydrogen sulfide. The primary contributors to biological growths are algae and bacteria.

A professional irrigation evaluation will gather extensive system operating pressure and emitter discharge rate information. System operating pressure information is important since the discharge of many microirrigation emitters is pressure dependent.

The emitter discharge is the amount of water per unit time that the microirrigation emission devices discharge. Usually this is expressed in gallons per hour (gph) or liters per hour (lph).

With a little guidance and motivation, it is not difficult to do an evaluation of your own microirrigation system.

Drip irrigation system in a vineyard. Photo: L SchwanklIn evaluating a surface drip irrigation system, there are two main items of interest: (1) the average emitter discharge rate, and (2) the variability of emitter discharge rates.

Double-line surface drip used in a young orchard. Photo: L. Schwankl.A self-evaluation of a surface drip system provides information on the systems pressure distribution and the discharge of the sampled emitters.

Microsprinkler irrigation in a walnut orchard. Photo: L. Schwankl.In evaluating a microsprinkler system, there are two main items of interest: (1) the average discharge rate for the microsprinklers, and (2) the variability of microsprinkler discharge rates.

A flow meter installed at the head of a microirrigation system or small flow meters placed at the head of selected lateral lines can help you detect clogging. Saddle-mount propeller meter installed at the head of a drip system. Note the instantaneous (gpm) and totalizing (gal) registers. Photo: L.

Microsprinkler irrigation use in a walnut orchard. Photo: L. Schwankl.A self-evaluation of a microsprinkler system provides information on the systems pressure distribution and the discharge rates of the microsprinklers sampled.