Progress in the Goulburn Wetlands

 

There are some of you that might argue that a weed filled paddock with a stagnant pond collecting miscellaneous rubbish and occasionally re-inoculated with garden refuse from cheapskates around the town is not necessarily a bad thing and that what we’re doing is only progress  from our subjective point of view. Then there will be many who might argue that human progress as a whole is a superficial and fallacious construct, especially in the face of cultural annihilation, genocide, extinction rates that surpass the demise of the dinosaurs, out of control anthropogenic climate change and, perhaps worst of all if you really think about it, acidification of the ocean to and beyond the point at which marine creatures that have dwelt on the planet since life began can no longer function as their shells get dissolved faster than they can survive and reproduce. We would, perhaps unsurprisingly, disagree with the first point and, while consenting to the second, regard what we are doing as our small bit to make a real difference locally if not globally. Now I’ll try to justify this with a record of our deeds in May Street, Goulburn.

Click on any image below to see an enlarged version.

 

Warning: this is a particularly long and detailed page

 

 

What we found in 2010 … a photo essay

It was near the end of the 9 year drought and only the deepest pool had any water in it.

It was near the end of the 9 year drought and only the deepest pool had any water in it. There had been just enough rain to make the living weeds green.

 

There were a few black ducks and grey teal. Occasionally a white-faced heron came along to try its luck. But most of the birds were starlings, house sparrows, green finches, blackbirds and common (Indian) mynas.

There were a few black ducks and grey teal. Occasionally a white-faced heron came along to try its luck. But most of the birds were starlings, house sparrows, green finches, blackbirds and common (Indian) mynas.

 

 

Then it rained more and the flats got a bit of shallow water in them.

Then it rained more and the flats got a bit of shallow water in them.

 

 

Then in December of 2010 the Mulwarree flooded the golf course and wetlands.

Then in December of 2010 the Mulwarree flooded the golf course and wetlands (Photo: Greg West).

 

 2011, the year we began working in the wetlands

 

A group of boys and young men almost gazumped us by carving up part of the flats to make a set of bmx bike jumps.

A group of boys and young men almost gazumped us by carving up part of the flats to make a set of bmx bike jumps.

The Goulburn Group (TGG) applied for and received funding from the NSW Building Communities grants program. We had asked for $100,000 and received $70,000. As a result Goulburn Mulwaree Council, who had recently unanimously voted to support the project, added funds to make up the difference. The Hawkesbury-Nepean Catchment Management Authority provided an additional $27,000 to assist with plant and weed management.

The Goulburn Post reporting on TGG's grant submission.

The Goulburn Post reporting on TGG’s grant submission.

It was at this stage that The Wetlands Working Group was set up as an interim body to oversee the management and implementation of the project. This group consisted of members of The Goulburn Group (Rodney Falconer, Bill Wilkes and David Marsden-Ballard), GMC Councillors (Nina Dillon and deputy mayor Bob Kirk), members of other groups and volunteers (such as Ray Shiel and Jenny Ashwell), Peter Mowle (who as GMC’s past Chief Engineer had acquired the wetlands and proposed a similar project several years beforehand), representatives of the Goulburn Golf Club, Steve Watts from the Lands Department — our biggest neighbour, owning the golf club lands and the river — and members of GMC staff, most notably Debbi Rodden (administration, secretariat), Jack Miller (environment, planning and heritage) and Kevin Stewart (water management).

 

Dr Lambert-Tracey's report, completed in 2012.

Dr Lambert-Tracey’s report, completed in 2012.

Other participants in these formative stages included David Proctor (engineer) and GMC’s heritage consultant and archaeologist, Jennifer Lambert-Tracey who was flown from Queensland to inspect the old brickworks site. She produced a report of her initial investigations and was very supportive of the notion of conserving and incorporating the remains as part of the larger wetlands project.

Divalls' bulldozers helping construct the dam wall. This helps retain water levels for longer periods, while ensuring the water doesn't get too deep.

Divalls’ bulldozers helping construct the dam wall. This helps retain water levels for longer periods, while ensuring the water doesn’t get too deep.

Divalls Earthmoving and Bulk Haulage came to the party and — while utilising most of our $70,000 on the construction of rock berms (to divert and slow stormwater) and to create a a bridge/dam and culvert — donated the equivalent of tens of thousands of dollars in materials, labour and other in-kind contributions. A dam with culverted spillway was constructed to keep the berms just above the high water mark while allowing an average maximum water depth of about 1.2 metres, sufficient to allow water plants to thrive, but shallow enough to maximise photosynthesis under water.

A change in the human use of the wetlands ...

A change in the human use of the wetlands …

During their excavations, the Divalls crew wisely kept the bike and scooter users on side. Their works attracted many young viewers and all seemed to be going well. Then another group came along, dug a huge ‘wombat’  burrow and gathered all sorts of debris and waste materials, including lounge furniture, gave every sign of being unfriendly to the “scooter kids” and were actively using illicit drugs. This was of concern to us, our neighbours the golf club, Council and ultimately the police. By now the debris, carved tracks, jumps and holes had begun to also be of alarming extent. TGG was moderately sympathetic towards the perceived needs or desires of neighbourhood teenagers and children to have bike jumps and similar facilities nearer than those provided by Council in central and western Goulburn. Unfortunately this site has environmental and safety concerns and these unstructured and unsupervised activities in the long grass were incompatible with the environmentally and socially condoned vision for the wetlands. Our concerns were further compounded by some of the children throwing brick debris at the ducks and hitting them.

 

Then a second large flood came along in December 2011, isolating Eastgrove for a couple of days.

Then a second large flood came along in December 2011, isolating Eastgrove for a couple of days. This is May Street, with the wetlands to its left, a few hours after the peak of the flood. Photo by and thanks to Greg West.

 

 2012 … building on the foundations of the previous year

Our greatest fear of the new year was that everything we had worked on might have been swept away in the flood. In fact the flood provided a marvellous learning experience.

From it we learned that:

  1. the  water doesn’t come down the Mulwarree: it goes up it, then back down. This is because the Wollondilly is a larger river with steeper banks and holds a larger volume of water with greater flow rates and force. At the junction of the two rivers, a couple of kilometres downstream near the gaol, the Wollondilly forces its way up the Mulwarree as well as continuing downstream to the Hawkesbury and Sydney. After the peak, the water then drains back down, often at considerable velocity.

    All that was left of the bike ramps and burrow after the flood had subsided, March 2012.

    All that was left of the bike ramps and burrow after the flood had subsided, March 2012.

  2. Since the wetlands are on the inside bend of the Mulwarree, most of our 30 acres experienced only a gentle rise and fall in water levels rather than being heavily eroded. High water velocities did occur in and beside the old river and adjacent to the main river. As a result the old fence between the May Street bridge and East Street (the first cross street on May Street south of the bridge) was pushed over and filled with grassy debris. The Forces of Nature kindly demolished our end-of-2011 problems: as the flood-waters receded there was only a little trace of where mounds and holes might have been. But none of our berms, temporary tracks, car park, bridge or rock walls were damaged. Only a little crushed granite in the approach to the bridge was removed. Thus any built structures had to either be solid enough to bear water pressure and allow the water plenty of room to escape, or they need to be constructed only where flows are gentle.

    Flood debris choking and pulling over the old fence, north-east corner by the river bridge.

    Flood debris choking and pulling over the old fence, north-east corner by the river bridge.

  3. None of the plants, especially not the weeds, seemed to be badly affected by the flood waters, so long as the flow was not rapid near them. Even then they were only pushed over. A few days after the flood-waters receded the grasses had sprung up again and any bare patches were almost immediately colonised by tall thickets of yellow flowering buchan weed (a type of mustard). It gave us the impression that — so long as we were able to plant native trees, shrubs, grasses and grass-like plant species with enough time to grow strong roots before the next flood — our plantings should survive periodic inundation.

    Buchan weed (a type of wild mustard) thicket within a week of being out of the floodwaters.

    Buchan weed (a type of wild mustard) thicket within a week of being out of the floodwaters.

  4. Rocky Hill, immediately to the east of May Street, is extremely porous, a significant reservoir of water and, at least in our minds, its stability is questionable. For months after the flood, regardless of weather and with or without rain, water poured down from the hill into the wetlands or down May Street.
  5. Water levels in our larger pools mimicked those in the rivers nearby as the flood subsided, only far more slowly. This meant that the bottoms of the pools were relatively impervious and that our dam had been effective.

 

In January 2012 FROGS (Friends and Residents of Goulburn Swamplands) was incorporated as a Landcare Group, taking over as an independent community organisation from The Wetlands Working Group established earlier with Goulburn Mulwaree, TGG and others. Starting from a core of 6 people (David Marsden-Ballard, Rodney Falconer, Bill Wilkes, Ray Shiel, Debbi Rodden and Peter Mowle), the group was gradually expanded with volunteers and other interested members of the community and established affiliations with other community groups in Goulburn. Every Wednesday a group of between 6 and 10 volunteers would meet at the wetlands and work on various aspects from about 9 AM to about 1 PM. Meetings were held (often in the private room of Roses’ Cafe for lunch) at which former members of the Working Group came together with a core executive to plan our next and future steps.

The impenetrable barrier of weeds and thorn bushes was removed along May Street, a new sealed car park was established on May Street at the southern edge of the wetlands, bollards were established, rubbish removed and the boulders adjacent to the bridge/dam culvert were cemented in. Several experiments were undertaken to judge the most effective way to remove weeds and establish a landscaped area using local provenance native plants,  many of which were tussocks of grasses and graminoids. These methods included:

 

 

 

 

 

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