Irrigation Uniformity

The effectiveness of the sprinkler system as regards the overlapping of the irrigation arches y uniformity in the distribution of water distribution is a very important parameter for the diagnosis of the irrigation management.

A traditional method of its analysis is the test by means of rain gaugein particular the test for uniformity of distribution of the lowest quarter. Its calculation is as follows:

DU= (average number of millilitres collected in the lowest quarter / average number of millilitres total) x 100

That is, the 25 % of the lowest readings give an average which is divided by the total average.

A DU of 100% would indicate perfect distribution uniformity. In general, a DU of 70% is accepted as good, while a DU of less than 55% is considered poor.

Today, thanks to tools such as POGO, it is possible to determine the overall efficiency by taking into account how irrigation water infiltrates into the soil profile and is available to the roots. Soil type, soil compaction, surface hardness, slope, drainage and environmental conditions affect water infiltration and thus its availability in the soil profile. Therefore, the determination of evenness distribution, as a single analysis, cannot alone ensure irrigation efficiency. This was proven in an irrigation audit carried out in Georgia, where in addition to a rain gauge irrigation test, soil profile moisture was measured by means of moisture sensors similar to the POGO technology.

The results have determined that moisture gradient maps reveal differences, through a detailed analysis of moisture distribution. It is not possible to determine this from traditional rain gauge methods alone. 

The technology used to create spatial maps of moisture gradients is starting to become more prevalent, but unfortunately its adoption by maintenance managers, head greenkeepers and other decision makers is slow.

Once again Tiloom, through its team of engineers and precise measurement tools such as POGO, is being instrumental in the efficient management of sports facilities.

References: IA 2003. Irrigation Association. Certified golf irrigation auditor training manual. Irrigation Association of America. Falls Church, VA.

STMA. Conducting an Irrigation Audit. Sport Turf Managers Association.