The last time the Wyangala dam overflowed was in 2000. If that that is the sort of rainfall that we can expect in our predicted future drier climate evaporation will negate any increased capacity of the dam, if it is ever filled.

It is time to look at our alternatives instead of debating the merits of Greta Thunberg's protest. There are large scale irrigation projects in the north awaiting investment and the potential of the Great Artesian Basin (GAB) to meet the needs of inland towns and irrigation should be evaluated.

The "Great Man-Made River" $US36 billion project begun by the notorious Colonel Gaddafi in 1983 in Libya now transports almost 6.5 million cubic metres of water daily through an underground 4000-kilometre pipe network from the Nubian Sandstone Aquifer System (NSAS) in the Sahara to the coastal Libyan urban centres. It meets most of the water requirements of Libya's six million people.

The NSAS is estimated to contain 150,000 cubic kilometres of water, enough to last a thousand years. The GAB, which stretches over a similar sized area, is estimated to contain 65,000 cubic kilometres of groundwater.

While water quality and gravitation feed favour the Great Man-Made River project, solar energy could answer the pumping and water purification energy requirements of an equivalent Australian scheme.

There is a urgent need for legislation with strong protections for whistleblowers, especially in the public sector, as indicated by the article "Watchdog powerless to protect: inquiry" (October 19, p15).

Whistleblowers Witness K, David McBride and Richard Boyle, along with lawyer and former ACT Attorney-General, Bernard Collaery, face harsh sentences in unjust prosecutions that should never have been brought. These prosecutions exemplify abuse of power.

Along with the raids on the ABC and journalists they are an attempt to intimidate truth-tellers and are a serious danger to our democracy. Arthur Moses, SC, recently said "Since September 11, About 75 pieces of federal national security legislation has been passed, and there has been a slow erosion of our freedoms" ("Security claims mask power play", September 7 p.30). Intimidation under the guise of 'national security' is now the practice of this government.

A rally to defend whistleblowers and press freedom, which includes speakers Andrew Wilkie, MP, Senator Rex Patrick, Sister Susan Connelly and journalist Jack Waterford, is being held this coming Thursday, October 24, 12.30pm on the Parliament House lawns. The rally is endorsed by Civil Liberties Australia, Timor Sea Justice Forum, Medical Association for the Prevention of War, and Independent and Peaceful Australia Network.

If we don't want our freedoms eroded, we need to speak up and oppose such travesties of justice.

Your edition of October 21 "What are they covering up?" was a bit dramatic to me considering freedom of speech is well established in this great country of ours.

Trying to coerce our government to open the flood gates is a bit extreme. I'm sorry to say there are some secrets that have to remain "secret" for the safety of our citizens and the country.

How many lives have been lost or destroyed by over enthusiastic journalists who wrote half-truths or let the cat out of the bag by divulging our agents overseas.

Yes journalists do have a job to do uncovering corruption, bad politics etc but, to allow outright openness is not on. Your mention of the ABC instant is a classic example of getting someone hurt due to a journalist wanting to make a name, and we can only hope is punished for stealing and divulging top secrets.

Some of these people are only in the game to create sensational stories with no consideration for anyone else. How many times have we seen the same old scene where a journalist runs up to a victim and shoves a microphone in their face and asks: "How do you feel".

The Canberra Times reported Ron Shamir saying he was promised protection for making a disclosure but was hung out to dry ("Watchdog powerless to protect", October 19. p15).

But Shamir lost his job because he refused to do the work he was told to do. The law reports show the dispute: whether his refusal justified sacking him. A single commissioner said no: a full bench said the single commissioner got the law wrong, and that the circumstances made sacking Shamir the right thing to do.

Shamir never claimed to Fair Work that he was sacked for making a disclosure, or for doing what the Inspector-General of Taxation required. That's because giving information to the Inspector-General wasn't why he lost his job.

The present Inspector-General, Karen Payne, thinks better whistleblower protection would improve their operating environment. It wouldn't have protected Shamir. He suffered nothing for giving the Inspector-General information.

Or should refusing to do your work be protected, by disclosing something else to someone else?

On May 20, 2017, President Donald Trump and Saudi Arabia's King Salman bin Abdulaziz Al Saud signed a series of letters of intent for the Kingdom of Saudi Arabia to purchase arms from the United States totaling US$110 billion immediately, and $350 billion over 10 years.

Even after all this a drone attack from Yemen knocked out half of Saudi oil production without a Saudi shot being fired.

Now 3000 more US troops have been sent Saudi to add some muscle to the big dollars spent on arms sold by the US. But if US$110 billion can't stop a drone, what can?

On the other hand, massive profits for the US military-industrial complex and that is, after all, the name of the game.

In his farewell speech in 1961, Dwight Eisenhower said "In the councils of government, we must guard against the acquisition of unwarranted influence, whether sought or unsought, by the military-industrial complex".

Great advice, Dwight. That was 58 years ago, but no one in American heard you.

I cannot believe that anyone can consider repealing the Medevac Bill and yet this is what the government wants to do. How can they be so inhumane as to deny medical treatment to innocent sick people?

The refugees on Manus and Nauru have been incarcerated for up to six years, despite having committed no crime, and many of them are sick because of what the Australian government has done to them.

Furthermore over 50 men have been arrested and imprisoned for two months in PNG by the PNG government, without access to phones or lawyers. What justification if there for imprisoning these men? What justification is there for Australia keeping refugees indefinitely on Manus and Nauru?

So I ask all politicians not to vote to repeal this bill which is the only ray of hope for a group of very sick people. If the bill is repealed there will inevitably be more self-harm and suicides.

Senator Jacqui Lambie has indicated that her vote on the repeal of Medevac will be based on the merits of the humanitarian argument, and not on political "horsetrading". However, there is a confusing contradiction in her statement that the recent events in northern Syria have caused her to have to consider the national security implications of repealing the Medevac legislation.

On one hand, Senator Lambie says her concerns are based on the fact that "word doesn't always get back to people in ... war zones not to get on boats because you won't be allowed in Australia".

And yet her concerns seem to be also based on a belief that if Medevac remains in effect, word of that would get back to the people fleeing Syria and encourage them to head to Australia.

The Medevac legislation has been in effect since March 2019 and there has been no opening of the floodgates for boat arrivals.

The Medevac legislation is a minimalist measure which has enabled very sick people to receive necessary medical treatment. It contains ample safeguards against any potential threat to national security or community safety.

The gripping series Fake News in the Trump White House must be approaching its denouement. Will President Trump be successfully impeached? Will he resign before that can happen? Will he take preemptive action on the basis subversives are undermining effective governance by declaring a state of emergency and/or martial law and postponing the scheduled 2020 election until such time as internal conditions permit? Fact is stranger than fiction.

Congratulations to Australian Community Media for finally giving prominence to the increasing levels of government secrecy and attacks on the media. I look forward to continuing front-page stories on this critically important issue.

The passengers on the world's longest flight said they felt refreshed and rested after their more than 19 hour non stop flight from New York ("Qantas flight sets record", canberratimes.com.au, October 20). I'm not surprised. They were all in business or first class. How would they feel if they had done the trip in economy? Alan Joyce, Qantas CEO in economy; now that's not going to happen, is it?

Our Prime Minister has told farmers he's "praying for rain". What if God has decided that we need to have a drought? Aren't you going against God's wishes then? Maybe we need a bit more action on climate change than hoping for miracles.

Our Skywhale is uniquely Australian and certainly memorable. But she should have her own Proper Name: I suggest that modest Australian native Myoporum insulare, otherwise known as Boobialla.

Barry Harris (Letters, October 15) wonders "how long before Scott Morrison's irritating smirk starts to wear thin with the Australia Electorate?" How good is that electorate? How good is that smirk? How good is that Barry Harris? How good is not hearing a sentence starting with "How good is..."

Congratulations to Pat Campbell on being nominated for his depiction of the silver fern ("Canberra Times cartoonist Pat Campbell among Walkley awards finalists", canberratimes.com.au, October 18). I was in New Zealand on March 15 and Pat's response will remain a special, albeit sobering memory of tragic event.

Now that Floriade is over I would like to mention the cultural activities of our city continue. Scottish organist David Gray, will be playing the 1933 Compton Theatre pipe organ and grand piano on October 30 at 7.30pm. Tickets: trybooking.com.

Ian Mathews (Letters, October 19) confuses the UN's agencies with the peak body. It has failed to take timely action on the Syrian emergency. No amount of good work by WHO or UNICEF changes that.

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