Granted that pigs and probably climate change have played their part, [but] unless steps are taken, the arrival of horses in substantial numbers has the potential to affect our drinking water, as well as the nature of places like the headwaters of the Cotter River in the south-west of Namadgi.

Steps taken would need to be in accordance with RSPCA guidelines and they presumably will.

As for the NSW government, it has no intention to "manage" the brumbies as Krestensen suggests. The NSW legislation gives blanket protection to feral horses in Kosciuszko National Park. There are already 6000 to 8000 horses there and current laws will allow their numbers to spiral.

Those working to oppose the NSW legislation and implement actions to deal with the problem are motivated by a love of the park and the steps they want taken are based on scientific, not ideological, grounds. I am a horse lover as well as a bushwalker but their numbers cannot be allowed to grow.

Stan Marks, Hawker

Dumb and dumber is the government's response to the passing of the Medical Transfer Bill. The government and its coterie of acolytes on Sky News are cerebrally challenged by logic and reason. Hypocrisy, insults and fear mongering are their preferred modi operandi.

Jon Jovanovic, Lenah Valley, Tas

How can the National Capital Authority and the federal government have faith in the ability of the ACT government to deliver against the high development and landscaping standards and associated regulations that will be set down for the massive redevelopment of the kilometres-long and now nationally symbolic Gateway corridor ("Shoddy work slips past rules", February 12)?

If the ACT government can commit to delivering on these strict requirements without constant developer attempts to ignore them or avoid compliance on specific matters, then the government should apply many of these quality and design requirements for residential construction across the whole of Canberra, for the sake of this city's long-term future.

Sue Dyer, Downer

Bravo Dick Smith for his splendid advertisement calling on journalists to make the connection between population growth and the current problems in the Murray-Darling (The Canberra Times, February 12, p7).

For the past 15 years I have traversed the country between Canberra and South Australia to visit a son and his family. Usually I follow the Murrumbidgee River which starts in a fairly healthy way to the east but by the time you get to Renmark, it's green. Over the years, ever more irrigation-fed vineyards extend to the horizon.

This summer, I followed the Murray then cut across the Wimmera. Along the river, there were orchards and vineyards, all dependent on its water. Beyond the irrigation zone, the land could only support a few scattered sheep. To the east of Charlton in western Victoria, there was a vast olive plantation. "Where do they get their water?" I asked the motel owner. "Oh, there's plenty of water," she said.

Coming back at Echuca, however, the river levels seemed right down. Clearly, there is too much water being taken from the river system and it has to be put back. This means some irrigation-dependent towns will have to contract. Inland Australia is not going to support ever more people, even though that is offered as an alternative to migrants cramming into our congested cities.

Everyone, not just journalists, needs to understand there are resource limits to population growth.

Jenny Goldie, Cooma, NSW

I write regarding Tony Dillon's article ("Labor is exploiting misunderstandings about franking credits", The Canberra Times, February 6).

Mr Dillon has an excellent grasp of the numbers but not the policies underlying them. When a company makes a profit, they are liable to pay company tax. The money withheld from the gross dividend amount is not "a withholding tax deducted from [the taxpayer's] gross dividend". It is company tax that belongs to the Commonwealth. So the taxpayer receives only what belongs to her, namely, the dividend net of company tax (in Mr Dillon's example, $7000).

That net dividend forms part of the taxpayer's personal income. Crucially, the $3000 withheld as company tax does not form part of the taxpayer's income, as it belongs to the Commonwealth. That is why she never receives the company tax portion of the dividend – it does not belong to her.

However, the Commonwealth has decided not to tax the same income twice (first with company tax then personal income tax). So, the taxpayer only pays the difference (if any) between what the company owed on its income (30 per cent tax) and what the taxpayer owes on their income (anywhere from 0-45 per cent tax). That is, the Commonwealth doesn't tax the gross company profit twice, but it does tax at the higher rate if the applicable personal income tax rate is higher.

There is no logical place in this regime for refunding company tax to taxpayers whose marginal rate is less than 30 per cent. All that does is transfer company tax to an individual taxpayer instead of the Commonwealth.

But company tax is public money, so it should be available in its entirety for public expenditure, not private gain. Where people get most confused with this is need. Some people with low taxable income are poor and needy. Others are not. But need is not relevant to the consistent application of tax policy.

If making tax policy consistent by closing the franking credit refund aberration is unduly burdensome to the poor and needy, that should be rectified by social policy – not continuing to have inconsistent tax policy.

Christopher Budd, Turner

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