The ‘Big Flush’ and what happened next

The ‘Big Flush’ and what happened next

Monday, June 1, 2015

The outcomes of these initial mitigation practices were not immediately obvious over the next few months…the stream remained heavily silted and water clarity remained very poor. However, that all changed in June 2015 due to a very heavy rainfall event. We received 158 mm over two days (120 mm in the first 24 hours), which had the effect of flushing out the waterways.

Within 2-3 days of the end of the rain we revisited various waterway sites on the farm and discovered that the streams were running clear. In fact it was then that I realised that at the monitor point by the Cattle Yards that the stream actually had a gravel and rock bottom…previously this had been covered in a heavy layer of silt.

Monitoring site 1 Cattle Yard Stream after heavy rains in June 2015. Note the gravel bottom

However, the question on everyone’s mind was would the streams remain clear or simply silt up again? If our earlier mitigation practices did indeed target the sources of waterway degradation, then the streams should in theory remain in a better state than prior to the rainfall event. We are happy to report that nearly two years later, the streams have remained relatively free of sediments and the stream bottoms remain visible.

It is not perfect yet but it is getting there.