Engineering works for 'Barmah Choke'

Subject: Engineering works for 'Barmah Choke'
From: Keith Stockwell <>
Date: Tue, 13 Feb 2007 20:44:02 +1100
The Barmah-Millewa wetlands are a Ramsar site, a wetland of international
significance. The forest ~ much but not all of which is Red Gum forest,
grassland plains or wetlands ~ and its wetlands attract many birders, the
relatively new bird hide at Reed Beds Swamp and Barmah Lake being
particularly popular.

The Echuca and District Branch of BOCA has prepared a free brochure on
birding spots of Barmah Forest (Victoria) and another on the birding spots
across the Murray on Gulpa Island (NSW). These can be downloaded as pdf
brochures from the Branch's web site. There are also pictures of almost all
birds found in the area (follow links from URL listed near the end of this

At a National Press Club address in Canberra late in January, Prime
Minister John Howard announced a ten-point water plan.

The plan envisages lining or piping channels, allocating 50% of water
savings to the environment (and especially to the six icon sites, including
Barmah-Millewa Forest) and the remainder to irrigators, capping ground
water use, investigating the possibility of developing more agricultural
areas in northern Australia, restoring the Great Artesian Basin, addressing
water over-allocation and undertaking major infrastructure works in the
Murray-Darling Basin. The Australian government proposed taking over the
management of the Basin from the eastern mainland States.

Specific mention was given to 'engineering works' at the Barmah Choke ('The
Narrows'). The exact nature of the engineering works has not been spelled
out and i have been unable to obtain information. I have asked that the
matter be placed on the agenda for the this month's Will this be good news
or terrible news for Barmah-Millewa wetlands (a Ramsar site)?

About 15,000 years ago, the course of Murray river was blocked at Bama when
land to the west was uplifted several metres (the Cadell Tilt Block). The
uplift was west of a fault running north south for many kilometres.

The uplift blocked the Murray for years, causing a huge lake to form.
Eventually, new channels were formed around the fault (Gulpa Creek, Warwick
Creek, The Edward, The Narrows, etc.

The main stream flowed south-west from the lake in a new channel to the
Goulburn. Echuca-Moama would be alongside the Goulburn today had the uplift
not occurred.

Over the past few hundred years, the Murray has deposited silt on its floor
and sides as it has flowed through the once large large, separating the
lake into several (including Moira Lake and the Reed Beds in NSW, Barmah
Lake and Hut Lake in Victoria.

In winter and spring, floodwaters used to exceed the capacity of the new
channel, The Narrows or Barmah Choke, a section of river without high
banks, flooding the wetland and drowning any young Red Gum seedlings which
had germinated over the past year, so that much of the forest was Moira
Grass Plain. Such birds as grebes, cormorants, egrets, ibis, ducks, waders
and Brolga thrived on the Moira Grass Plain

In late summer, when the level of the Murray fell, the wetlands drained and

River regulation has badly affected the wetland. Floods are no longer as
frequent or as deep, allowing many Red gum saplings to survive and take
over much of the Moira Grass Plain.

It should be stressed that the very existence of the Barmah-Millewa
wetlands is dependent upon the 'choke' which constricts the amount of water
which can be conveyed through the forest. When the capacity of the choke is
exceeded, sections of the forest floods. Red Gum and Moira Grass Plains
depend upon flooding for their existence.

Most of the flood water eventually returns to the river.

Sandhills mark the edge of the once huge lake. They support Callitris pine
and a wide variety of shrubs. One of my favourite spots is Langmans
Sandhill on Gulpa Island where Gilbert Whistler and many other bush birds
can often be seen. Engineering works are unlikely to affect the sandhills.

In my opinion, any attempt to widen, desnag or deepen 'The Narrows' would
be bad news for the forest and would damage a geological formation of
national significance, a perched river with paired silt jetties.

I think that such action is unlikely in view of the likely protests and
environmental damage.

A by-pass channel or pipeline is more likely would be terrific for the
forest if it was used only in summer and spring,and not at all in winter or
autumn, so that the old natural flooding patterns could replicated. What I
fear is that, in view of its enormous cost and existence, such a by-pass
would be used over winter and spring, denying the forest some of the
flooding which would otherwise occur.

The area is very flat, and because the Murray can flow backwards when the
Goulburn is in flood, a by-pass channel would have to be very long. Unless
carefully planned, a by-pass could turn out to be an expensive white

The Echuca and District Branch h of BOCA has arranged for a birding cruise
aboard a small flat-bottomed vessel, 'MV Kingfisher' through The Narrows
late on Saturday afternoon (17th February). This is a good opportunity not
only to observe The Narrows but to observe kingfishers and other birds at
fairly close quarters, the boat skipper Benita knowing where many nests are
located along that stretch of the river. There are a few spare seats;
contact me directly if you are interested.

Meanwhile, most wetlands around Echuca-Moama are dry at the moment, even
drought refuges like Hut Lake. Further afield, near Kerang, a few lakes
have water and lots of birds. Cullen Lake is reasonably good at the moment
(e.g. hundreds of Black Swan, hundreds of Shelduck, Marsh Sandpiper,
Sharp-tailed Sandpiper, Caspian Tern, White-bellied Sea-eagle) as is Round
Lake (near Lake Boga golf course ~ Great Crested Grebe, Australasian Grebe,
Blue-billed Duck, Coot, Marsh sandpiper, Sharp-tailed Sandpiper, Musk Duck,
others)). Lake Tutchewop is low and very salty at the moment: a 5km survey
there on Sunday only revealed two species, Silver Gull and Starling. Whilst
in the area, I also called in to the nearby Tresco West Bushland Reserve
which is always a good spot for Blue Bonnets.

Moves are under way to nominate both the Kerang Lakes and Barmah-Millewa
Forest as Important Bird Areas.

There are extensive notes about Barmah-Millewa and other reserves on my web

Keith Stockwell


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