ORAL SUBMISSION TO THE PANEL HEARING OF THE CITY OF KINGSTONLOCAL PLANNING SCHEME AMENDMENT L-33 (KINGSTON LODGE)

Date: 11 August 1998

SPEECH NOTES

The Mordialloc Beaumaris Conservation League was the first local conservation group to support Melbourne Water's proposal to develop a chain of wetlands along the bank of Mordialloc Main Drain as a means of improving water quality.

However, our main objection to the Kingston Lodge Residential Development L33, is based on the fact that this proposal is sited in the green wedge on a flood plain with a high water table and in this respect is in conflict with the SENUS report which clearly describes the type of development (if any) which would be acceptable in the green wedge. The criterion is for: "limited, low density environmentally based residential development". 700 houses is a gross over development of this site and does not conform to the SENUS findings.

The Framework Plan, a joint review of the Keysborough wetlands for the City of Greater Dandenong and the City of Kingston, concluded that: "there is strong strategic planning, environmental and landscape grounds to reconfirm the long term value of the non-urban area (the green wedge) from a metropolitan and local perspective". Given the strong endorsement of the Framework Plan and the retention of the green wedge, why is the Kingston council now so eager to breach those guidelines and set a precedent for further encroachment into the green wedge by other councils?

Our second objection is also based on the Strategic Review of the Keysborough Wetlands which recommends that any development in the green wedge must : "genuinely address the landscape, amenity, ecological and hydrological objectives and limitations" (it is the hydrological objectives and limitations that I wish to address). Nature designed flood plains for floods, not for the financial gain of the few. This particular flood plain, the site of the proposed Kingston Lodge development, has been satisfactorily performing the role of an ephemeral wetland for countless eons as part of the Carrum Carrum swamp. For example, the Ecological Australia consultants report describes the site as:

"seasonal wet meadows seasonally inundated with shallow water".

Now we are being asked to approve an artificial wetland development costing approximately 7 million dollars based on consultants reports containing a farrago of "ifs", "maybes", and "possibles" when referring to this wetland development.

The Complexity of this wetland system apparently makes it impossible for consultants to give definitive answers to major design problems, for example:

We are told by consultants that these problems can be dealt with at "the more detailed design stage".

Not good enough! Sinclair Knight Mertz in their Groundwater Review of Proposed Kingston Lodge Development sees the possibility of: :

In referring to the last point, the potential development of acidic sulfate soils, the document Wetlands - their ecology. function. restoration & management proceedings from a seminar at La Trobe University, describes acidic deposition as: "Increased acidity which usually changes the composition of zooplankton and benthic algal communities. Several stream benthic species are sensitive to acid stress. Survival of fish may also be reduced".

To counteract saline intrusion into the groundwater of what are supposed to be a series of freshwater wetlands: "a clay lining of the open water section is recommended", and yet The Manual of Wetland Management (DNRE; p 120) states: "Clay is not impervious as a lining. It is also conceivable that the clay could be by-passed via pathways created by animal burrows and tree roots". The drying out of clay during periods of low water levels will result in the cracking of the clay lining also allowing intrusion of saline water.

The Review of Kingston Lodge Wetland System consultants report (p.4) also highlights the matter of groundwater/ wetland connectivity which raises questions of potential salinity impacts on aquatic ecology and resultant wetland pollution of the groundwater - and this is likely even without the long term effects of predicted climate change on water tables.

Dr AB. Pittock of the CSIRO (Aspendale) and Dr Eric Bird, former head of the Geography Faculty, Melbourne University have concluded that predicted climate change will result in higher flood levels in estuarine waterways such as Mordialloc Creek and its upstream environs, therefore increasing salinity problems in the soil and water table. Therefore developments of the magnitude of the Kingston Lodge scheme require planning for the long term, not short term planning for the duration of the consultants contract until the developer moves on to his next financial bonanza.

That there is a real possibility of salinity intrusion into the open water area, especially as a result of excavation to a depth of 3 metres for fill for the residential development, is evidenced by the example of Edithvale North wetlands where a breaching of the peat layer during construction has resulted in an influx of high salinity groundwater.

The suggestion that an impermeable layer inserted during wetland construction can prevent significant movement between the two systems is not convincing since, as stated previously, entirely impermeable liners or layers do not exist as landfill operators will attest, and confirmed by numerous investigations into leaching from landfill sites in the region bounded by Heatherton, Oakleigh and Springvale carried out by officers of the (former) Department of Water Resources - now absorbed into the DNRE.

The suggestion in the Review of Kingston Lodge Wetlands System that, in addition, sub soil drains may also be required to deal with storm water reticulation within the residential area as a means of : "managing potential groundwater moundings" highlights the complexity of this project which we are being asked to approve despite an enormous number of unresolved issues in the wetland section of the project alone. For example, the conclusion reached in this report is that groundwater problems: "can easily be resolved through attention to the sealing of the beds of wetlands and the provision of drainage at the more detailed design stage".

Nothing about this wetland development will be "easily resolved" given all the "maybes", "possibles" and "ifs" scattered throughout the consultants' reports. Incidentally, sealing of wetland beds would require compaction of suitable clay (if it can be found) and cost millions according to an authoritative source.

I refer now to the Sinclair Knight Mertz report into Groundwater (p.4) 5.2, Acid Sulphate Soil in which the consultants indicate that Potential Acid Sulphate Soil exists on this site which is low lying with a relatively high water table. The danger here is that if potential acid sulphate soil is excavated for fill for the residential component of the development then, when exposed to the air, this soil may become Actual Acid Sulphate Soil. For example: "Exposure to air oxidises pyrite to form sulfuric acid and release of silica and heavy metals. These oxidation products are highly toxic to aquatic organisms and can also corrode steel and concrete engineering products".

So that in addition to the harm caused to aquatic species by the release of contaminated soil, there is the danger that if this fill is used for the residential component of the development, structural damage to buildings could occur. The EPA will require the developers to adhere to the NSW Guidelines for the Management of Acid Sulphate Soil before any buildings are approved.

Finally, the consultants Review of the Kingston Lodge Wetlands emphasises the need to address: "regional groundwater implications of extensive wetland and detention storage development across the lower part of the catchment". For example:

Once again we are told that these matters need to be addressed: "at the more detailed design stage".

The claim by the proponents of the Kingston Lodge development that their concept reflects: "key policy documents and guidelines" is completely misleading. It does not!! This development certainly does not: "ensure that use and development within the non-urban area does not compromise metropolitan urban growth strategies".

The 700 house residential development destroys the concept of the green wedge in the City of Kingston and sets a precedent for future grabs by avaricious developers in sections of the non-urban areas of adjoining cities.

Author: M. Rimington

Back to the MBCL Resource Page