It should be no surprise that New Zealand's environmental legislation is a source of major political conflict. But before the Resource Management Act is 'reviewed' we should consider what its purpose is.

If you think any proposal that provides any economic benefit at all should be approved as quickly and cheaply as possible, then the RMA can be dispensed with. If that is where he is coming from, there is a certain logic to Don Brash's view on the Act. Why waste time and money just going through the motions? Just let rip.

But if you want development to be ecologically sustainable, built to the highest standards and broadly acceptable to the community then a process is needed to seriously scrutinise proposals, weigh evidence carefully and say "no" to the minority of projects where the environment is at risk.

The fact is that the RMA is currently not meeting this standard. According to a recent NIWA study, few, if any, of our lowland rivers are clean enough to swim in; district plans are constantly varied to allow more coastal sub-division; our unique biodiversity is being destroyed little by little; and new buildings are often allowed to affect their neighbours' quality of life.

While realisation of the Act's actual intentions can be considerably improved, the types of concerns being voiced by some businesspeople and politicians seem to be based on myths and fear rather than reality. Economic growth has been high in recent years and unemployment is down, so is the RMA really deterring investment and blocking development? Almost all resource applications are granted, with less than three per cent being publicly notified for community scrutiny and less than one per cent being appealed to the Environment Court. Councils can sometimes be needlessly bureaucratic, but amending the Act will not fix that.

The main bogeyman raised by the RMA's opponents is that its processes do not adequately provide for the "national interest" where this diverges from local interests, and particularly "infrastructure projects" such as power generation and distribution, roads, sewage and water supply. There is no evidence to support this fear, either in the Act or in its application, unless one believes such projects should be exempt from scrutiny.

The purpose of the RMA is to enable people to "provide for their social and economic and cultural well-being and for their health and safety", while sustaining resources and the environment. So economic development, including the importance of infrastructure, already has weight in the decision making. Experience confirms this: the biggest roading project in Auckland at present, the Grafton Gully motorway, has had no RMA holdups and is proceeding smoothly. As have major power generation projects such as the 400-megawatt gas-fired plant at Huntly and the 90-megawatt wind farm in the Tararuas, which was approved in days and not taken to appeal.

On the other hand, a new highway south of Nelson was turned down because of serious air pollution risks and Project Aqua might have failed the consent process because of its massive environmental effects and inability to generate power in dry winters. Neither of these proposals were declined because the national interest was not adequately considered. Isn't this how the RMA should work?

At introduction the Act gave central government several mechanisms for providing some national interest guidance to local decision makers. For nearly 13 years these processes have been virtually unused, as successive governments have left local bodies to flounder. The RMA itself cannot be blamed for that. National Policy Statements could be guiding councils, but there are none, except the mandatory Coastal Policy Statement. National Environmental Standards could be ensuring consistency across the country, but the first ones, on air quality, were only just issued last week. Such mechanisms provide the certainty and consistency across councils that industry calls for. They should be given time to work.

A ministerial call-in procedure was designed for projects with major national significance. Until the Aqua application, it had only been used once. The Act cannot be blamed for central government failing to fulfill its defined role.

The fact is that many infrastructure projects, claimed to be in the national interest, are contentious because there are more sustainable alternatives. They should have to face rigorous comparison with other options, rather than being given an easy ride to approval. In some places extending national grid power lines could be avoided by building smaller power stations closer to demand, paying some consumers to shift their peak load and sensible energy efficiency measures. These are much cheaper and more durable alternatives and will serve economic development just as well. The alternatives should be properly examined. Where expanding the national grid is the best option, but needs consent from many different councils along its length, it would be simple to require them to appoint a single hearings committee.

In some places a new motorway could be avoided with better public transport and urban planning. That comparison should be properly examined too, otherwise we will continue to build old fashioned, "think big", unsustainable projects instead of shifting to the path of the future.

A number of other business concerns can be addressed without overturning the Act's purpose and principles, threatening public participation or environmental quality. Council hearings would be improved if all who sat on hearings committees were required to have training in RMA procedures, which is available now but only on a voluntary basis.

Increased funding in recent times has meant that the Environment Court has been able to clear its backlog and reduce the number of consent appeals from 3000 in the mid-1990s to 1100 today. The time it takes now to get a hearing is usually less than six months. Better case management would resolve more cases more quickly. There are mediation and negotiation processes available now and they could be used more. The Court is already able to deal with vexatious submitters and appellants through the award of costs and has the power to strike out evidence that is not relevant.

The environmental shortcomings of the Act do need a rewrite if we really want to clean up rivers, protect species and habitats and guard our open spaces and landscapes. They mainly stem from the "effects based" approach that sprang from the Rogernomic economic thinking of the late eighties. The fact that the RMA makes it very difficult to deal with the cumulative effects of many projects all doing the same thing and to allocate scarce resources to the best use is what the Government's current review should be addressing.