Before implementing routine or remedial maintenance on a micro-irrigation system, test the water source for physical, chemical, and biological properties to determine emitter plugging potential.
It is important to take a representative water sample:
If the water source is a well, collect the sample after the pump has run for about half an hour.
If sampling surface water, collect the sample near the center of the source about 1 ft below the water surface.
Check for water source variability by taking samples several times during the irrigation season.
To accurately measure water pH, alkalinity, dissolved iron, and hydrogen sulfide, analyze well water with a field test kit immediately after sampling.
Use Table 1 to estimate the plugging hazard of irrigation water based on a standard analysis.
Table 1. Chemical criteria for plugging potential of micro-irrigation water sources (Pitts, 1990).