In late-2016 the drought broke and the dam was at near full capacity by early-2017. In March 2019, Chaffey Dam had fallen and to about 24 per cent of capacity and there were community calls to Tamworth Regional Council (TRC) for more water restrictions to be imposed but we were reassured that the water supply was adequate for community needs.

In August 2019, when Chaffey was at 20 per cent capacity, Water NSW acknowledged the seriousness of the situation for the approximately 60,000 residents dependent on the town water supply.

In mid-2020, TRC acknowledged that there was no feasible method of supplementing the town supply by road transport or by train.

At the same time, the western town of Walgett had depleted its town water supply and was being serviced with bottled water.

In September 2019, the state ministers Melinda Pavey, Kevin Anderson and Damien Tudehope announced that an emergency pipeline would be built from Chaffey Dam to the Dungowan Dam pipeline at an estimated cost of $39 million.

In November late-2020, the La Nina weather event emerged with Chaffey Dam now at 41 per cent capacity.

It is noted that during the Christmas week 2020, approximately 9GL flowed into Chaffey Dam from that rain event.

In August 2020, the draft Blueprint Plan prepared by TRC consultants identified that water security was the number one issue for any planned expansion of Tamworth.

In 2019, the state and federal governments jointly declared that a new Dungowan Dam would be built to secure the Tamworth water supply.

The proposed new Dungowan Dam was to have a capacity of 22.5GL, significantly larger than the 6GL current Dungowan Dam, however less than a quarter of the capacity of the existing Chaffey Dam.

The proposed cost of the new Dungowan Dam including a new $100 million pipeline is $480 million.

As an aside, very rough calculations reveal that a dam wall below Terrible Billy Creek at Dungowan would have a catchment area approximately half the size of Chaffey Dam.

One of the many pieces of information that emerged at Level 5 restrictions was that business and industrial operations use about 50 per cent of the water supply and that at Level 1 restrictions these operators required approximately 25 per cent of town supply.

Many of these business have now implemented engineered water saving and recycling systems.

The major question that has been asked by the average person is, how, in the space of the two-and-a-half years 2017, 2018 and mid 2019, did the Chaffey Dam supply fall 80GL to 20 percent capacity in mid-2019?

A completely satisfactory explanation has not been received. At the water meetings during 2019 and 2020, TRC estimated that average town water usage varied between 20 to 25 megalitres (ML) per day.

Assuming a 25ML usage per day, annual usage is approximately 9,125ML per annum. 9,125 ML is equal to 9.1 GL.

There are transmission losses of about 100 per cent so releases of 18.2GL are required to meet Tamworth Regional Council's town water supply requirements per annum.

In other words, Chaffey Dam releases of 80GL over the two years is equal to four (4) years town water supply.

A graph supplied by WaterNSW in August 2019 of water orders and water releases shows that there were water losses between January 2019 and April 2019 equal to 'two years Tamworth supply demands', the implication being that losses were due to evaporation and alluvial aquifer recharges.

In addition the report reveals 6.2GL were released for environmental flows in 2017 and 3.9GL in 2018. That same document states that the drought was the worst on record.

It is asserted that management of the Peel Valley Water Sharing Plan by WaterNSW is the central enquiry.

Based on this information it is suggested that implementation of treated sewerage water reuse as drinking water is highly questionable particularly when the Hunter H2O report (2015 P.53-55) on long-term water options stated it was the most expensive alternative when compared to the other options.

It is suggested that other uses in construction, industry, and business where non-potable water is to be reused could be found, to alleviate the draw down by business and industry on potable drinking water from the town water supply.

The Peel Valley Water Sharing Plan, that governs the water releases from Chaffey Dam by WaterNSW, and which failed in the previous periods, was rolled over again in late-2020.

This plan uses 10-year-old data and an algorithm for water releases that may or may not be reliable.

The new Dungowan Dam is planned to be completed within four years and that process commenced in mid-2020, so completion should be in late-2024.

At the end of that four year period a new Peel Valley Water Sharing Plan will completed.

It is proposed that the this new Peel Valley Water Sharing Plan will cover not just Chaffey Dam but Dungowan Dam and the whole of the Peel Valley.

That is, unless the NSW Government gives ownership of the dams and pipelines to TRC.

It needs to be remembered that the federal government has given the NSW Government the grant for $242 million, so there is some basis for arguing that ownership should revert to the TRC.

The Tamworth community needs to be in prepared for the imposition of a new water sharing plan.

The first issue is that all community members need to be united in their approach, the irrigators, the farmers, businesses, industrialist, residents, environmentalists and TRC. There will not be a perfect solution, only the best possible compromise.

The second issue is that as much verifiable information as possible be gathered from the many local people with long experience and knowledge of the intricacies of the hydrology of the Peel Valley and the Namoi Valley.

The third issue is that a good understanding of how the Peel Valley fits into the existing Murray Darling Basin Plan needs to be developed, and a reasonable assessment of what its continuing impact will be.

Attendant to this is the projected impact of climate change as predicted by the NSW Government Office of Environment and Heritage. CSIRO predicted in 2006 that Tamworth would have approximately 8 per cent less rainfall on average by 2030 and that rain events might be more infrequent but heavier.

The fourth issue is the need for preparation of a robust assessment to be made of the then existing water infrastructure and its adequacy for the task, an assessment of the Peel Valley needs and an agreed position on what is acceptable to the whole community.

The final issue is to ensure complete and verifiable information is gained to establish the root cause of the failure by WaterNSW in the management of the Peel Valley water supply that potentially may have had dire consequences.

From that point on, that documented community position would be negotiated with the NSW Government and Water NSW.

Stephen Maher, Tamworth

Critics of Michael McCormack can be forgiven for thinking he's a bit of a dunce.

Each time he has had the Prime Ministers mic he manages to say something that, to put it in the nicest possible way, "is not quite thought through."

The fact that none of his reckless utterances as acting PM have been particularly useful nor helpful to our country, should come as no surprise.

They are the desperate cries of self-preservation from a wounded man amidst a perpetual coup within his ranks.

The knives from the last spill have never been put away. So God forbid we upset the sycophants of Barnaby, Canavan, Kelly and that other 51st State citizen George Christensen.Almost to the day last year it was "Little Lucifers" that came to his rescue.

This time, not being hindered by the fires as a distraction, he was able to select from the whole smorgasbord of dog whistle models on offer."Free Speech", "Anti-China sentiment", "Black Lives Matter", "Both Sides Just As Bad" and "Trump Just Had A Bad Day".

It was hard to know which one to blow on first, so seeing his top spot in the media was only going to last a few days, the Federal Member For Riverina decided to test them all out at once on the first journo he encountered.

It's little wonder that every time McCormack has stepped into acting PM role, the average persons response is "Who the heck IS this guy??"

Graham Strong, Boree Creek

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