Irrigation Update

Irrigation Update

Further to the information provided last week here is some additional information briefly outlining the Irrigation Management Practices that are in use here at Blackwood Golf Club.

Our irrigation practices are based on our Department of Water licence allocation to water the measured area of ‘irrigated turf’ on the golf course. This total area is @24.5 Hectares, which is broken down into three areas –

1. Elite – Greens/surrounds and tees.
2. Premier – Fairways.
3. Turf – Roughs and carries.

The golf course is irrigated using a fully automatic, constant pressure system with the majority of sprinklers on the course being electric valve in head which allows for greater individual control.

The average irrigation cycle throughout the hotter months uses @ 1,000000ltrs (1 ML) of water/night using a combination of some of the 61 programs that are run through the dedicated irrigation computer.

The water we use for irrigation is a combination of water from the main dam and the water that we extract from the main three metered bores located on the course (13^th/14^th/15^th).  The bores are activated when we move into full course watering and not at a pre-determined date, typically this is around mid- October. This is because they are a finite resource that has to be managed carefully to ensure that we have enough water to see us through to the autumn.

Water from all sources is pumped into the 500,000ltr holding tank alongside the 15^th fairway and then pumped out onto the course.  To achieve the average 1,000,000ltr cycle already mentioned, it is necessary to pump from all sources to make sure that the input into the tank exceeds the required output onto the course. Currently, we are in a situation where because of the low levels of the dams it is not possible to be able to complete a 1,000,000ltr cycle. Therefore it was necessary to make the decision to start to conserve water until such time that I have sufficient resources to allow me to resume full watering (as explained in the Course Conditions update in last week’s e-news). 

Part of the overall watering process in a normal year is that when there is reduced demand due to favorable weather conditions, water is pumped into the tank and the excess out through the overflow into the holding dam at the 15^th green. This water is then manually drained down into the main dam where it is re-cycled back into the irrigation tank for use on the course. Assuming no rain and current bore levels we are still several weeks away from being able to raise the level in the main, and thus complete a full irrigation cycle.

To date this year has been particularly dry, and normal watering on all areas was implemented up until late December when it was necessary to make the decision to conserve water. The unusual thing about this year’s weather pattern compared to other dry years is that we have only twice received rainfall events in excess of 10mm since September 7^th.

Obviously since this decision was made, this has led to the fairways drying out. However, at this current time although the fairways are very dry and not aesthetically pleasing to the eye, there is still full grass coverage. The couch grass is not dying; its natural response in times of drought stress is to go into dormancy and will recover with minimal damage when normal watering recommences. A perfect example of this recovery are the lush green areas on the 2^nd and 7^th fairways which were inundated with water from the burst to the irrigation mainline which occurred last Saturday.

The height of cut on fairways has been raised to further protect the couch and as soon as we are in a position to do so they will be targeted with wetting agent and fertiliser applications to increase their health and vigour as we head into the autumn period.

In our current situation greens and tees are naturally the highest priority for receiving available water and the current bore levels are consistent with previous years which would indicate that there will not be an issue with keeping up with demand to maintain these areas.

December Statistics

	December 2012	December 2011	average
Rainfall	13 mm	26.5 mm	37.5 mm
Year to Date	838.5 mm	807 mm	841 mm
No. of rain days	3	3	-
Average Temp.	27.3°C	29.7 °C	-
Average Humidity	58.9%	52.4 %	-

As can be seen from Decembers statistics, we have had another dry, warm month with less than average rainfall. Last Sunday brought us a very welcome and much needed 11mm of steady rainfall. This is only the second time since September 7th that we have received a rainfall event of more than 10mm. Our average for the period from September 1st  through to the end of January is 254.5mm, and we are currently sitting at 110.5mm. That is only @43% of our average rainfall in what has been a unusually long dry spell for us here in the Adelaide hills.

I am in the process of preparing a detailed report that will provide further information for members about our current situation regarding the dryness of fairways, our irrigation procedures and the strategies we have in place to bounce back from these very trying conditions we are currently undergoing.