Kimberley Appropriate Economics Interim Report - Australian ...

Prior to the construction of the ORD, almost no thought was given to the impact on Aboriginal people
and contemporary cultural values. The increasing western population and social settings brought
about by the irrigation development also impacted upon cultural heritage values. A significant increase
in access by non-Aboriginal people to traditional sites resulted in reducing or destroying ceremonial
significance of these places. Access to country and sacred sites became impossible following the filling of
the dam, resulting in the flooding of ceremonial sites, hunting and fishing grounds, and seasonal routes
(Kimberley Land Council 2004).
Traditional Owners have expressed concern over environmental impacts associated with the
development such as the diversion of natural drainage flows through channels and levees instead of the
billabongs of the black soil country associated with the Dreamings (Barber & Rumley 2003).
3. Ecological
Ecological values were not considered prior to the building of the dams. No surveys were commissioned
to understand the ecological system (land, water, plants and animals together) or the impacts of the dams
upon that system. Two biological studies did take place prior to dam building, recording data on birds
(Robinson1961) and flora (Gardner 1945), but these were not undertaken in association with the irrigation
development and merely coincided by chance. The lack of baseline data regarding the pre-dam state of
the Ord River System impedes accurate determination of current and future conservation status as it is
difficult to estimate the rate and scale of change (Watkins et al 1997). All other research undertaken prior
to the damming (eg from about the 1940s) of the river was associated with the agricultural potential of the
area and viability of various crops (Graham-Taylor 1982).
Despite the modifications to the river system, some areas are recognised as having outstanding
biodiversity value. Lakes Argyle and Kununurra were listed under the Ramsar Convention in 1990 due
to their importance to waterbirds as a dry season refuge, although this was not an intentional outcome
of the dam construction. The lakes have also become an important site for the saltwater and freshwater
crocodiles, where numbers have increased to levels such that there were 25,000 freshwater crocodiles
counted in Lake Argyle in the 1980s (Webb 1989). The creation of the dams upstream (and the Lakes
Argyle and Kununurra Ramsar site) are impacting on the downstream Lower Ord Ramsar site, although
the effects on the ecology have never been comprehensively evaluated (Watkins et al 1997). Lakes Argyle
and Kununurra are still actively evolving thus certain changes to the river’s ecological character may be
inevitable, with the lower Ord floodplain currently in a state of ecological re-adjustment (Watkins et al
1997).
A number of research studies have been undertaken since damming to investigate the environmental
impacts on the present ecology. These are briefly mentioned below to give an overview of the current
impacts since development and also as a lesson of the environmental problems that can arise from
development decisions in the absence of rigorous research.
3a. Flooding
The building of the ORD and KDD has greatly reduced the frequency and intensity of flood flows,
and increased dry season river levels leading to a loss of seasonality (Start & Handasyde 2002). This
directly affects water levels and flushing times in the river and upper estuary, the salinity regime in
the estuary, the frequency of inundation of flood plains and wetlands, and the dynamics of sediment
erosion and deposition (Salma et al 2002).
The mean annual flow has decreased by 30% from a highly variable 4500GL pre-damming, to
around 3200GL post-damming with far less variation (Rodgers 2003). Changed flow dynamics
have resulted in significant changes in the geomorphology of the Ord River (Doupé & Pettit 2002,
Trayler et al 2002, Wolanski et al 2001, WRC 1998, WRC 1997).
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