Planning to fail on Murray's health

I was hoping that with a new leader at the helm the Murray Darling Basin Commission (MDBC) might take a new approach to river health issues.

But when the new chief executive officer, Dr Wendy Craik, addressed a Water Summit in Sydney last week the commission's line still seems captive to the doomsayers.

Dr Craik's speech was still endorsing monitoring systems that through their very design would ensure the river failed basic health tests.

She said the Commission would report on river health through the Sustainable Rivers Audit (SRA) which measured river health relative to "the condition that would exist now in the absence of human influence experienced during the past two centuries".

In other words, instead of measuring whether, for example, Murray Cod numbers are now increasing or decreasing, the Commission was seeking to determine whether there are as many Murray Cod now as there were 200 years ago.

This is the same approach that was used in the now discredited 2001 assessment The Snapshot of the Murray-Darling Basin River Condition.

An inherent problem with this approach is that we will never know how many Murray Cod there were in 1805.

Furthermore, the Murray River is a highly regulated system -- Dr Craik acknowledged this in her presentation -- yet its health is being measured relative to an unregulated, natural system.

This is likely judging an apple against the features of an orange.

The dams, weirs and barrages have fundamentally changed the river's ecology and this should be acknowledged in any monitoring program.

An extensive study of the River's insect fauna undertaken in 1980-85 determined:

The overall diversity is high at all sites with the exception of those downstream of impoundments and the sites along the River in South Australia.  The number of taxa collected in the Murray (439) compares favorably with other Australian River systems.  The River Murray differs from the Meuse and many other large river systems in Europe and North America in that it has little industrial or domestic pollution.  Consequently, water quality is high and this is reflected in a high diversity of aquatic animals.  However, the influence of the river regulation has modified the fauna with the more tolerant, slow water forms dominating the highly regulated reaches downstream of Lock 9 (near Wentworth) and the true riverine fauna restricted to the stretches of River above Lake Hume.

This study accepted that the Murray was highly regulated and concluded the river had a healthy and diverse insect fauna.

In contrast, the 2001 assessment using a rational similar to the SRA, concluded insect populations were in "poor" or "extremely poor" condition.

Incredibly the 2001 assessment also stated that insect populations had shown improvement over the period 1980 to 1997.

At the Water Summit Dr Craik suggested that the SRA will "provide consistent, basin-wide information on river health".  It would not.

The media headlines when the study is released will be along the lines:  "Murray River fails basic health test" and of course "More water needed to save River".

Few will understand that the river "failed" because the scientists were making their comparisons with a hypothetical, well-watered, un-regulated, "pristine" system.

The MDBC should be collecting basic data on insect, fish and bird numbers and how they change seasonally, how they trend from year to year, and over decades.

This information should be publicly available on the internet, including for key indicator species for key sites.

It is really quite incredible that such basic information is not already available for such an important river system.

The MDBC has a new leader;  it now needs a new monitoring system for river health -- a monitoring system that will truly increase our understanding of the ecology of the mighty Murray.

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