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Stygofauna – keeping groundwater clean for 200 million years.

Stygofauna are any fauna that live in groundwater systems or aquifers. They can be  crustaceans, worms, gastropods, beetles, mites and fish.

Never seeing the sun, they have no circadian rhythms. They grow slowly, don’t have many young, live long lives and stay close to home. Some are from extremely old lineages, with ancestors dating back to Gondwana and Pangaea or the Tethys Ocean, 200 million years ago. Some display a close relationship with species from other continents which indicates that their ancestors came from a time before the break-up of the
super continents.

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It is because of their characteristics born of their low-energy environment, and their incredible age, a lot of stygofauna species are extremely rare and localised.

Stygofauna contribute important ecosystem services by creating a nutrient cycle, and have been recognised as indicators of groundwater health. The stygofauna are small enough to wander among grains of sand in the sandstone aquifers, purifying the water by eating bacteria – playing a similar role to earthworms in soil.

Stygofauna are amazing because they are an inconspicuous but important component of World biodiversity. They represent outstanding examples of adaptation and ongoing evolutionary processes, and contain many ancient lineages of high scientific value and conservation significance.

We know stygofauna are not very mobile, so they make poor colonisers. This means that if all the creatures in one locality are wiped out, it is unlikely that others will quickly replace them.

Stygofauna are vulnerable to extinction from environmental changes and human impacts.

The Pilliga Sandstone Aquifer has been found recently to contain rare species of stygofauna. A survey of 22 sites within the Pilliga Sandstone aquifer conducted in 2016-17 reported a total of eleven taxa of invertebrates, which included ten families from five orders of stygofauna. The results showed stygofauna exist across the entire area.

They are classified as of High Ecological Value in the Pilliga, as the area is covered by the Lowland Darling Aquatic Endangered Ecological Community, listed under the Fisheries Management Act 1994.

#GasFreePilliga

Healthy Rivers Dubbo IPC submission Narrabri Gas Project

Dugald Saunders confirms height of new dam on the Macquarie – its a whopper.

A new dam is being planned on the Wambuul Macquarie River, 200 metres downstream of the current weir at Gin Gin, between Narromine and Warren.

John Laws became interested in the project after Mel from Healthy Rivers Dubbo called him on Monday 20/7/20 to have a chat about it.

Dugald Saunders, member for Dubbo got on the next day and announced that the new dam would only be 1 metre higher than the the current weir at Gin Gin.

The current weir at Gin Gin is now about 4 to 5 metres high. It was a lot higher once, about 10 metres or so, before floodwaters had their way and trimmed it down.

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From the start, plans for the new dam are for a 14 metre high structure, with 10 metre high gates, capable of holding back 9,000 Megalitres of water.

WaterNSW have been saying that they will reduce the size of the structure following concerns raised by stakeholders about the significant impact the project would have on Native Fish and the Ramsar listed Macquarie Marshes downstream. They have talked about a structure with 3 stages of 5 metre high gates, capable of holding back 6,000 Megalitres.

However, in the official document (bottom of the first page) signed by WaterNSW on the 28th May 2020 that will inform the environmental impact statement, the project is described such:

Doc3-1 (4) Mel understood that while WaterNSW were saying they would reduce the height of the gates, the official documentation had not changed, so called John Laws back with serious concerns that the Member for Dubbo didn’t understand the scale of the project.

To finalise the question about the height of the new dam, Dugald wrote to John Laws and on Thursday 23/7 the following was read out on air..

The key sentence is “the full supply level of the new structure will be approximately one metre higher than the storage at Gin Gin weir prior to it’s failure.

Prior to it’s failure the weir was about 10 metres high or so.

In a round about political-speak way, Dugald Saunders has confirmed that as Mel and the official documents referenced above said, the new dam will have gates 10 metres high (while at the same time he appears to win the debate like any good politician would).

WaterNSW cannot be trusted.

For reference, 14 metres is almost as high as a 5 story building.

14 metres

 

Macquarie community rallies for the River.

No New Weir. Don’t Damn The Macquarie.

Healthy Rivers Dubbo has launched a community powered campaign featuring television, radio and newspaper advertisements to highlight concerns about plans to dam the Wambuul Macquarie River at Gin Gin, between Narromine and Warren.

Next month the Detailed Business Case for the proposed ‘Macquarie River re-regulating storage’ is due to be submitted, although there is no indication that the public will get the opportunity to see it. We know the cost of the project is over $30 million because of its classification, but the actual forecast cost is being kept from the public, and is expected to be a lot higher.

Don't Damn the Macquarie Ad - final

It’s time now for the NSW Government to change their plans. Don’t dam the Macquarie with a monstrous gated weir, instead rebuild the old Gin Gin weir at the same height, with a fishway.

Coral Peckham, Tubba-Gah Maing Wiradjuri,

“We’re concerned about our sacred sites along the river, and our aquatic flora and fauna. They all need water. Our aims and objectives are to look after Country for future generations.”

Sandra Peckham, Wiradjuri Bogan River People:

“No dam. If this dam goes ahead and a heritage site is destroyed, it will be just like what Rio Tinto did in WA, knowingly destroying cultural sites. “

Garry Hall, Grazier, Macquarie Marshes:

“Roy Butler has the opportunity now to stand up and represent the people of Barwon. This dam will be a disaster for communities, downstream graziers and unregulated irrigators in his electorate. We are the people who voted Roy in, and we need to know he is standing with us now.

“Preferred alternatives to improve water security would include the NSW Government changing its credit policy of allocating water that hasn’t fallen as rain in the catchment.

“The Ramsar listed Macquarie Marshes being in the seat of Barwon means Roy Butler must work hard to ensure the NSW Government meets its obligations as the manager of the internationally significant wetlands. How will those obligations be met when this project will mean a loss of important natural inflows to the Marshes every year?

“Reduced flows in the Macquarie below Gin Gin will mean the Marshes will be drier more often, and it will be even harder to connect the Macquarie and Barwon Rivers, which is crucial for native fish migration and the health of the Darling River.”

Mel Gray, Healthy Rivers Dubbo:

“Dugald Saunders has a choice to make. Will he listen to the community, or allow the river to be turned into an irrigation delivery channel that supports only a privileged few?

It’s time for Dugald to stop the haemorrhaging of public funds being used to design a project that will harm the river, wildlife, the Macquarie Marshes and downstream farmers and communities. Change the plans now – rebuild the old weir, don’t damn the Macquarie.”

David Harris, Project Manager River Repair Bus, Dubbo:

“Bit by bit we are changing the river and making it harder for native fish to survive. This dam will destroy habitat for Murray Cod, Trout Cod, Silver Perch and other species for a 30km stretch, and that includes drowning beautiful old River Red Gums that are hundreds of years old and cannot be replaced.”

“This dam would make a mockery of the many long hours invested by the community in repairing the habitat of the Macquarie River for native fish.”

Neal Harris, Western Paddlers NSW, Mudgee:

“As recreational paddlers, members of Western Paddlers NSW love paddling on the Macquarie River and the Macquarie Marshes. River paddlers seek out natural waterways, and more dams means we’re losing more and more of our wild rivers.

Thirty kilometres of still water, with no vegetation, poor water quality and reinforced banks is not what our paddlers expect or want to experience on the Macquarie, and we would regarded that section of the river a no go zone for paddling.”

Outstanding issues within NSW’s Final Draft Water Resource Plans and consequences for the Murray-Darling Basin Plan – June 2020. Wentworth Group of Concerned Scientists

Water Resource Plans (WRPs) outline how the management of water resources in a particular river catchment will be consistent with the Murray-Darling Basin Plan. They set out the rules and arrangements relating to water take, environmental water (‘planned’ and ‘held’), managing water during extreme events and strategies to achieve water quality standards and manage risks. They also specify environmental objectives and watering requirements. WRPs include groundwater systems and surface water areas (rivers and creeks).
Catchment-specific water plans that are established under state legislation also need to be updated for consistency with the WRPs and requirements of the Basin Plan (i.e. Water Sharing Plans (WSPs) under the NSW Water Management Act 2000).

If the WRPs and WSPs are accredited in their current form, there is potential for significant consequences for river health and Ramsar-listed wetlands of international importance including the Gwydir wetlands and Macquarie Marshes, undermining the Basin Plan.

Read more: NSW-WRP-issues-and-safeguards

Debit water accounts, rather than destroy the river.

Since 2014, WaterNSW have had a protocol in the Macquarie-Cudgegong Valley where if a water ordering customer has a history of cancelling water orders after they’ve been released from the dam, their water account can be debited by the volume of water they order, not the volume they pump.

To date, this protocol hasn’t been applied, rather water customers who habitually order more water than they need are only debited the volume of water they pump.

The capture of rainfall rejection orders is the main reason being put forward for the construction of the enormous in channel dam at Gin Gin.

Why should the public be asked to foot the large bill of over $30 million for a massive gated structure that will dam the river for 30 km, destroying Red Gums and making the river uninhabitable for native fish? 

This dam would withhold water from the internationally recognised Ramsar listed Macquarie Marshes, put the town of Warren at higher risk of running out of water, deny natural tributary inflows to the creeks and the Lower Macquarie and make connection between the Macquarie and Barwon Rivers even harder to achieve.

If water customers have a habit of ordering more water than they extract, then why doesn’t WaterNSW use the protocol and debit their accounts?

Water Order Debiting Macquarie Cudgegong

Dr Martin Mallen-Cooper comments on the new Macquarie dam at Gin Gin

The proposed Macquarie Re-regulating Structure would have a major negative impact on the river ecosystem, reducing biodiversity and reducing native fish populations.  There are four major impacts:

  1. Capture of tributary flows

All environmental water is not equal.  River flows that are uninterrupted by dams and weirs have extremely high ecological value, compared to flows that are stored in dams and weirs and re-released.

Uninterrupted river flows pick up nutrients (especially carbon such as dead eucalyptus leaves) and generate natural productivity of plankton, which is the essential food source of fish larvae.  This is the fundamental process of river ecosystems that sustains native fish populations.

If flow is uninterrupted over long distances, it has even greater ecological value as this enables fish that are a long distance downstream to detect the increasing flow (fish can sense the slightest increase in water velocity and have an extremely acute sense of smell) and migrate upstream to spawn so their larvae have greater survival.

The advantages of uninterrupted river flow are that: it occurs with a natural season; it has a natural rise and fall in river level; and it has natural, flowing water, hydraulics.  It also has no thermal pollution.  All these aspects contribute to these flows having high ecological value.

In the Macquarie Valley, tributary flows and rainfall events downstream of Burrendong Dam are one of the most valuable ecological assets that are presently sustaining native fish populations.  If the proposed regulator captures and re-regulates these tributary flows and main-stem flows that result from rainfall downstream of Burrendong Dam, native fish populations will have less successful breeding and populations will certainly decline.

The mitigation for this impact is to provide full transparency of tributary flows and rainfall downstream of Burrendong Dam.

 

  1. Impacts of variable water levels on river-edge and channel habitats

Tributary rivers of the northern Murray-Darling Basin have highly variable river levels, from floods to droughts.  However, these water levels vary over a very consistent regime over time – rising in floods but spending a lot of time at a low level with varying baseflows.  The time-scale and season of this variation is very important for fish.  Nesting species such as catfish and Murray cod establish a nest in spring and if the water level drops too much and/or too quickly they abandon the nest and there is no spawning that season[1].  This is an insidious impact as it does not become apparent until many years later as old fish die out and are not replaced by young fish.

Gin Gin Weir presently has a stable water level, while the new regulator will have highly varying water levels that will vary over short times scales within an irrigation season.  These are likely to impact breeding of Murray cod and catfish.

Under natural conditions in non-flood times, there are relatively stable water levels with occasional pulses of flow.  These conditions enable aquatic plants to develop in rivers, which contributes to the basis for the food chain, and ultimately fish survival and ongoing populations.  Regulators with highly varying water levels have weirpools that are characterised by barren banks and river channels, devoid of aquatic plants.  This breakdown of the aquatic food chain results in less food for native fish, reducing their health, resilience, and survival.

 

  1. Impacts on flowing-water habitats

Rivers have a natural mix of flowing and stillwater habitats.  Standing beside a healthy river, we all visually recognise flowing water and we recognise eddies, backwaters, pools and riffles – that is, healthy rivers have diverse river hydraulics (or hydrodynamics).

This hydraulic diversity provides habitat diversity and biodiversity.  There are aquatic animals and plants that specifically thrive in hydraulic diversity including: natural biofilms (fungi, algae, protozoa, bacteria), diatoms, plankton, aquatic insects, snails, mussels and fish.  The high biodiversity supported by hydraulic diversity supports a diverse food web, which contributes to resilience of the river ecosystem to withstand events such as droughts.

Weirs create backwater and pool-like conditions; where this happens and hydraulic diversity is reduced, biodiversity declines.  That is, some species become locally extinct – they cannot survive in the semi-permanent pool-like conditions.  Under natural conditions, prior to any dams or weirs, the Macquarie River could stop flowing and become a series of pools but only very rarely and for short periods of time.  Notably in 1902, in possibly the worst drought on record – the Federation Drought – when the Darling stopped flowing for 11 months at Menindee, the Macquarie River remained flowing the entire time.[2]

So flowing water habitats are a foundation of the Macquarie River ecosystem.

Two key species that thrive in flowing water are Murray cod and River mussel.  Murray cod are a valuable recreational fish and both species have high cultural and totemic value in aboriginal culture.  Many river mussels died in the last drought in the Darling River because there were no flowing water habitats for many, many months. Although adult Murray cod can survive in large pools, where there is good water quality, the survival of larvae and young fish is dependent on flowing water habitats and the diverse food webs that these provide.  Hence, to maintain the Murray cod population, flowing water and hydraulic diversity are essential to provide key nursery habitats.

The pool-like conditions that are created by weirs, not only reduce hydraulic diversity and biodiversity, but are also more favourable habitats for pest species like carp.

The proposed regulator will have three major impacts on flowing water:

  1. upstream of the regulator the backwater will be much greater than the present Gin Gin Weir, creating more still-water conditions and inundating Murray cod nursery habitats and River mussel habitat;
  2. as the level of the weirpool decreases upstream during the irrigation season, and more of the river channel is exposed, it will not have enough time to enable recolonisation of animals that specialise in this flowing-water habitat (e.g. aquatic insects, snails, mussels) – hence, critical food webs will not be established;
  • the regulator will capture tributary flows and local rainfall events – therefore passing less flow downstream which will directly reduce the extent and duration of flowing water conditions.

 

Dr. Martin Mallen-Cooper

 

 

[1] Stuart I., Sharpe C., Stanislawski K., Parker A. and Mallen-Cooper M. (2019) From an irrigation system to an ecological asset: adding environmental flows establishes recovery of a threatened fish species. Marine and Freshwater Research 70, 1295-1306.

[2] Water Conservation and Irrigation Commission (1956) ‘Surface Water Supply of New South Wales. Stream Flow Records Period to 31st December 1950. Volume 1.  Darling River Basin ‘ (V.C.N Blight, Government Printer: Sydney)

Your Say was heard! – Marshes and water birds to be considered in Macquarie dam EIS

** Impacts to the Ramsar listed Macquarie Marshes and migratory birds to be recognised as significant in Environmental Impact Statement! **

Public comment was recently invited on the EPBC Act referral for the Macquarie River re-regulating weir – which is a proposal to build another dam on the Macquarie River upstream from the Ramsar listed Macquarie Marshes.

This document will inform the Environmental Impact Statement for the project. WaterNSW prepared the referral, for the consideration of the federal environment department. In their proposal, WaterNSW considered that the impact of the new dam on the Macquarie Marshes and on migratory birds would not be significant.

Many of you prepared submissions, and disagreed with WaterNSW, instead identifying many ways that the dam would in fact have very significant impacts on the wetlands and the migratory birds that rely on them.

** YOU WERE HEARD! **

The environmental impact statement will now look closely at the significant impact the dam would have on the Macquarie Marshes and migratory birds.

Approved Referral

An alternative to the dam proposal was presented in the referral, that the current Gin Gin weir be replaced where it is – without the capability of creating a new dam. Any new structure would also have to incorporate a fishway. This would be a great outcome for the Wambuul Macquarie River!

 

The referral 2020-8652 – referral_Final produced by WaterNSW identified a lot of significant impacts that the dam is expected to have. Here’s a quick summary:

  • Reduced inflows into the Macquarie Marshes – small flows in dry years are critical to the Marshes.
  • 30km of river banks vegetation would be drowned.
  • Loss of habitat types such as riffle zones due to flooding and decreased water quality.
  • Loss of aquatic and river bank habitat for 30km.
  • Loss of snag habitat and spawning sites for vulnerable Murray Cod.
  • Native fish eggs would sink in the still water and die on the bottom of the river.
  • Fish in the area would have limited movement, even with the fishway, which is not enough to counteract the loss of habitat.
  • Loss of flowing river habitat.
  • The river banks will degrade and erode, land most likely will have to be lined with rocks for 30km – creating a sterile lifeless in channel dam.
  • Impacts to the groundwater recharge and groundwater dependent ecosystems.
  • Threats to native fish listed under the Fisheries Management Act – Eel-tailed catfish, Olive Perchlet Southern Spotted Purple Gudgeon, Silver Perch, Trout Cod as well as Murray Cod.
  • A registered Aboriginal heritage site will be inundated by the resulting weir pool.

 

It’s a dribble.

The Chair of Macquarie Food and Fibre, Tony Quigley spoke on ABC Central West Radio on Monday 11th May about the planned re-regulating weir at Gin Gin.

Tony explains (in his own words) that the giant structure will mean a loss to the environment and communities downstream of Gin Gin of the significant volume of 25 billion litres a year.

“… as irrigators we think there’s a real need for it, we think there is probably 25,000 megs a year that can be saved in the system that’s currently lost out the bottom to no real gain to the Marshes It’s a dribble all through the summer irrigation season. “

 

Macquarie water is sold before it falls as rain.

Burrendong empties at blistering speed.

The dam is massive – 1,188 billion litres. For context, Dubbo draws 8 billion litres a year to meet 70% of town water needs.

Burrendong has nearly bottomed out three times. In the summer of 2019/20 plans were in place to suck the dead water from the very bottom of the dam before letting the river below Burrendong dry up.

The river below Warren was allowed to dry up, followed by massive deaths of native fish, turtle, mussels, and other wildlife. People below Warren were left with no access to water from the river for their domestic and stock needs. It was a tough time.

Burrendong empties so quickly because the rules in the water sharing plan allow it to.

Water that has not yet fallen as rain over the Macquarie catchment is sold in advance.

The credit rule is essentially allocating clouds – water that hasn’t even fallen in the catchment yet,” said Celine Steinfeld, lead author of the paper published in the Journal of Hydrology, and also a member of the Wentworth Group of Concerned Scientists. “It was clear that water in the Macquarie had been overallocated.” (SMH Clouds become water entitlements in ad hoc river plan, paper finds)

The NSW Government knows the Macquarie is over allocated. On page 89 of their 2014 State Infrustructure Strategy they explain that while Burrendong is one of the biggest dams in state, the irrigation industry has developed to a size where the natural capacity of the river has been exceeded. There is simply too much water being sucked out.

When working out how much water to sell every year, the NSW Government does not take into account any rainfall and inflow data from before 2004. They choose to only look at last centuries rainfall patterns when is was a lot wetter.

The re-regulating dam to make everything even worse

The NSW Government are planning to add to our problems by building a re-regulating dam at Gin Gin that will allow even more water to be extracted.

The purpose of the enormous gated dam is to get more control over water in the river and make more water available for general security users. The effect is to convert unregulated flow to regulated flow.

This dam will be a loss to the environment of about 25 billion litres a year, according to Tony Quigley, Chair of Macquarie Food and Fibre.

The most effective, common sense way to address water security issues in the Macquarie Valley is to look at the glaring problems with the rules in the water sharing plan, not to pour many tens of millions of public dollars into a monstrous structure that will only benefit a privileged few.