|The physical, chemical and biological characteristics of irrigation water can affect pivot performance:|
Chemical: Saline water (such as groundwater) can corrode galvanised steel pipelines. Where the use of groundwater (or other corrosive water) is planned, stainless steel or poly-lined pivot systems should be specified. These cost more but will extend the life span of a system. Where saline water is used with ordinary galvanised steel systems, manufacturers commonly limit their warranty.
Biological: Any vegetative matter in the water needs to be screened out to prevent blockage of sprinkler nozzles. Water should be checked for the presence of algae as these might pass through filter screens and block sprinkler nozzles.
Physical: Sticks, grass, sand and silts and wind-blown weeds can be a problem. Sands and silts can wear out nozzles and deposit in overhangs. Normally a sand-trap is fitted at the last tower to prevent sand/silt from building up in the overhang. These should be cleaned out as required.
Pivot with corroded span pipe modified with a PVC pipe