The Dunham River issue: September 2004

 

Early September 2004 Kachana Pastoral Company hosted its fourth environmental workshop with the theme:

“Biomas: an ecological stabiliser in productive landscapes”

Guest Speakers were: Sam Bingham from Denver, USA and Dr Andrew Storey from Perth, Australia

 

 

Workshop topic: Dunham River Catchment Case Study

 

              “We’ll all be ‘rooned’… if the rain don’t come.”             “We’ll all be ‘rooned’… if the rain don’t stop.”                    

 

                         

                       

Flying Fox Yard: Dry season                                             Flying Fox Yard: Wet season

 

 

After a viewing of Wilma Keppel’s slide show on erosion: http://managingwholes.com/photos/erosion/index.htm

 

With the aid of map and white-board Chris Henggeler outlined a scenario that may be unfolding:

 

1. Restricted drainage of flood waters from the lower end of the Dunham River.

The perennial flow of nutrient rich tail-water off the Packsaddle Plains irrigation area into the Dunham is leading to increased vegetation which restricts the drainage of flood-waters in the river channels. Despite significant sections of river-bank having been eroded away in recent years, passage way for flood-waters is still restricted.

2. Increasing floodwaters emanating from higher up in the Dunham catchment.

Soil-exposure and the pealing away of loose deposits until bedrock is exposed, is leading to accelerating deterioration of the capability of the remaining soil to capture and retain rainfall; this leads to increasing run-off. Inherited soil-exposure problems have been made worse in recent years by late season burning and questionable stocking regimes over many years.

http://www.abc.net.au/kimberley/stories/s492225.htm

 

His conclusion:

If current trends persist it is only a matter of time before we will experience significant damage to down-stream infrastructure.

Risk already exists for:

Property downstream from where the Dunham and Ord Rivers meet

Both bridges over the Dunham River

Sections of the main highway between the Diversion Dam and the lower Dunham bridge

 

One of the choices we as a community may need to make is:

Do we focus on finding out what is going to happen and prepare for crisis management?

or

Do we as a community accept in general the predicament we are in and begin to focus on addressing the root cause in the hope of eventually avoiding reoccurring crisis type situations that are a direct result of deteriorating catchment health?

 

 

We then formed groups and discussed the “Dunham River issue”…

 

Resulting comments included:

 

 

AFTER-TOUGHTS:

 

Is there really a problem?

General community awareness seems to focus on individual issues:

Frequency/extent of fire

Location of salinity

Single flood events

Drought areas

Location of fish kills

Weed infestations

Loss of biodiversity

Cane-Toads

Human health problems

Etc.

There seems to be little to no recognition of the fundamental problems that lead to such symptoms…

 

Is not “health” the key?

… The general health of our broader landscapes?

… of landscapes which surround our production and living areas…

… of landscapes which supply our recreation and the attractiveness of the area…

… but more importantly of landscapes which supply our requirements for abundant clean water and which should perform the purification processes that protect us from disease…

 

If landscape health in general is in decline, the sorts of issues or symptoms listed above become more obvious; yet when landscape health improves these sorts of symptoms soon vanish.

 

Just like in a human body where fluid and nutrient uptake and conversion can indicate much about the basic health of a person (even to lay people), so in any landscape no profound rangeland knowledge is required to observe some basic indicators that tell us much about what is actually going on:

Landscapes need to be able to capture and retain moisture and (solar) energy to perform the natural purifying processes of air and water and to be able to provide the nutrients that build and support biodiversity.

 

Living soil (not just ground up parent rock particles and dead organic matter) literally forms the skin of our productive land-surfaces. When soil erodes so does the basis of any land-based economy; including that of whole nations…(how would the economy of your own body function if you were to lose significant portions of skin on a regular basis?)

 

What then may be the effects of a whole catchment deteriorating directly up-stream of a small community like Kununurra?

 

A detailed report by Kachana Pastoral Company on the state of the Dunham can be found at:

http://members.westnet.com.au/satlink/ENVIRONMENTAL-LITERACY/Dunham_River.htm

 

This update was provided by Kachana Pastoral Company: September 2004

 

For other contributions to local/regional environmental issues please click here

 

Kachana Pastoral Company promoting ‘environmental literacy’ and ‘functional science’:

www.environmental-literacy.com      (Learning to read what Nature is telling us now.)

 

 

 

Back to the slide-show on Erosion by Wilma Keppel

http://managingwholes.com/photos/erosion/pictures/slide16.htm