Two cheers for Gerald Kaye’s column “We can’t go on like this” (14 May, page 34)

We can’t. He’s right to say that the ever increasing number of levies such as section 106 are now self-defeating. They undermine the very developments needed to pay for the infrastructure required for development.

How many times does it have to be said that development follows infrastructure? Every country except us seems to know this. Payment for infrastructure can only come from the investment value it creates. To get forward funding and delivery, we need a mixed economy of tax and rent that supports a mixed economy of public and private investment. The fine-tuning of levies and tariffs is diversionary. Public investment is about to fall off a cliff, so now is the time to put the financing and infrastructure delivery at the top of Vince Cable’s in-tray.

And one boo for suggesting that sustainability is an add-on that can be dealt with at detailed planning stage - that’s why it continues to be so expensive and inefficient. If people find it difficult to plan seriously for climate change now, just think what fossil fuel shortages and price volatility will do over the next decade. As the volcano has reminded us, nature doesn’t recognise an entitlement to business as usual.

Stephen Hill, land economist