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Saving Chains of Ponds

By Gretchen306 posted 10-07-2019 15:04

  

I deduce that before Victoria was grazed and mined our waterways were very different. Early surveys seem to affirm this: maps of the plains and broad valleys often include clear italic notations 'Chain of ponds'. Doubtless, dense or very mature riparian vegetation lined their banks, and debris-laden floods scoured out the holes, keeping them deep and more or less permanent.

In my youth I roamed the banks, reaches and cut-off bends of the straightened-out, de-snagged Latrobe River, bulldozed from time to time of their numerous stands of silver wattle. The river engineers' object: get rid of that water as fast as you can, so it doesn't flood our farms.

Fifty years later my wife and I bought a bush block near St Arnaud with a series of 19 small ponds excavated along a moderately steep gully and subsequently stabilised. Around the same time, I read Peter Andrews' thoughts on Australian flood plain management. Basically: Hold water as long as you can, where it falls!

Then, perusing Google Earth some years ago, I noticed unusual features along Middle Creek, 10 kilometres SW of St Arnaud. As you moved upstream the raw gullies that so characterise northern Victoria, gave way to - yes!!! - an intact chain of ponds. On-ground examination later with the landowner confirmed my assumptions: a series of largish 'bathtubs'; when one is full, the water trickles gently downslope to the next one, and so on.

I could see that, once hoofed animals such as sheep and cattle displaced the gentler indigenous grazers, the newcomers, tracking in and out to drink, broke down the intervening earthen barriers between the pools, over which runoff had for millennia more or less gently trickled. Continuous gullies soon opened up.

The photo below shows part of what I saw, thanks to Google.

Note the creek is still fairly intact where the cover is better - obviously there's been less grazing here of late - the primeval creek bed resembled a string of sausage. But to the east where the land is hammered, even today, the creek is a gutter, often almost ramrod straight!. All the way more or less for 30-40 kilometres to the Avoca River!

That led to work on our 95 hectares at Adams Road, where there are now 100 waterholes (we call them gilgai), mainly small water bodies - of the original 10 'traditional' farm dams - that we are slowly 'decriminalising'! In other words, converting them to wetlands.

Thinking broadly, the pre-European waterways of our state would have been full of large- and medium-sized debris. The heaviest floods, such as we had in 2010-11, would have swirled this debris around like an auger, and flushed out the resulting silt, thereby continually keeping the holes deep, and rich in habitat and organic matter, as in food, or riparian wildlife. Remember, some holes along the Murray were apparently 40 metres deep. Broadly this type of waterway would have benefited Aborigines in manifold ways - until the Manifolds and fellow graziers came along.

Written by: Rob Youl


#ChainOfPonds
#ThisWorksHere
#CoastWaterways
#VIC
#Wetlands
#HabitatRestorationRevegetation
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