Balcombe Park Reserve & Long Hollow Heathland Wetland Restoration Project
Balcombe Park Reserve and Long Hollow Heathland are managed by Bayside City Council, located adjacent to the Beaumaris Campus of the Sandringham Secondary College in Reserve Road, Beaumaris. (Melways:86
C5) Both sites are close to each other and are part of what was once the ‘Long Hollow Swamp’. This swamp was once present in the area but was drained for residential development.
Balcombe Park and Long Hollow Heathland are both areas with remnant wetland vegetation. Their biodiversity has a key role in Bayside’s bushland and open space network. Long Hollow contains woodlands of regional significance and heathlands of State significance in addition to being the
only location for a number of locally significant species. It is the site of the most diverse single remnant of the noted “Sandringham Flora”.
Balcombe Park is an area of regionally significant remnant vegetation in Beaumaris, containing good examples of indigenous heathland floral species and communities. Balcombe Park is the only area of heathland within Bayside where surviving marsupial Dasyurid species (Antechinus agilis) have been identified. Prior to being identified at Balcombe Park, the nearest known population was previously thought to be at least 25 kilometres away. Antechinus show broad preference for dense undergrowth and litter, and higher densities occur in wetter environments (Menkhorst 1996).
Cropper (1996) indicates that the original vegetation of the Reserve was
swamp dominated by Pink Swamp-heath (Sprengelia incarnata), Swamp Paperbark (Melaleuca ericifolia) and/or Scented Paperbark (Melaleuca squarrosa). The north-east edge of the Reserve was Heathy Woodland probably dominated by River Red Gum (Eucalyptus camaldulensis), Swamp Gum (E. ovata) and/ or the more common Coast Manna Gum (E. pryoriana).
A natural wet soak area exists on the western side of the Reserve. The area
has a natural ephemeral water regime that is dependent on the catchment from the surrounding area. The main change that has occurred to the land in and around the Reserve is the draining of the swamp system. The natural drainage has been altered and now most of the water is carried away through sub-surface storm water drains or via the water table.
These changes have left only a small pocket of remnant wet soak species. The soak provides a wet soil habitat for plants as distinct from open ponds for aquatic species. Sufficient wetland-style habitat may attract additional bird species such as Snipe, Brush Bronzewings and Quail.
Cropper (1996) identified that the Reserve provides the best opportunity to
re-establish a swamp community within the City of Bayside. Pavey (1996) indicates that the Reserve is an area of core habitat in the City.
Long Hollow’s heathland contains areas of “wet heath”, where open water
exists in the Heathland for no more than a couple of months of the year and this does not always occur. The dieback in the Eucalypt species may be the result of this altered hydrology. There may be additional impacts from this altered regime which require reviewing. Long Hollow Heathland is now mostly drained. Comprehensive planning and design is required if the hydrology of Long Hollow Heathland is to be restored.
Storm water drains that pass the reserves run out into Ricketts Point Marine Sanctuary. It is hoped that any modifications to the hydrology would allow the storm water to be passed through the reserves to improve storm water discharges into the Marine Sanctuary.
Proposal
The development of drainage serving adjacent residential development is believed to have deprived both Balcombe Park and the Long Hollow Heathland of natural wetting events. These hydrological changes are implicated in ecological changes at the sites and represent a threat to the ecological health and sustainability of the floristic communities. The lack of current hydrological information and assessment of this situation serves as a critical impediment to the initiation of management strategies – Council cannot embark on a works program to restore natural flows to the areas based on the existing hydrological information. However, the cost of undertaking the necessary research for an uncertain outcome means that it remains “below the line” in Council’s budget proposal assessment process. A funding injection would help to break this impasse by allowing the necessary research and design work to be undertaken in a risk free environment.
The project
proposed is to: – Conduct a hydrological assessment of natural catchment of Balcombe Park and the Long Hollow Heathland to establish pre and post – development hydrological regimes and provide the necessary information to support the design of a modified drainage system that mimics natural regimes for the floristic communities while retaining the drainage standards for adjoining residential and other land – Develop a design
for a modified drainage system that meets the needs for the two sites and
adjoining residential and other areas.
The modified
drainage system design would them form the basis for future Capital Works
Project proposals for consideration in Council budgets.
The Friends of Long Hollow and Balcombe Park would like to thank Phillip Johnstone from Bayside City Council for providing supporting content in the preparation of this proposal.
References:
Bayside City Council 1996, BalcombePark Bushland Management Plan.
Bayside City Council 2002, Bayside Bushland Strategy.
Pavey, C. 1996, Bayside City Council Fauna Survey and Management Guidelines, WBM Oceanics Australia.
Cropper, S. 1996, The Vegetation in Native Bushland Remnants within the City of Bayside, Victoria, Botanicus Consulting.
Cropper, S. 2001, Annual Monitoring Report for the City of Bayside’s Native Vegetation Works Program, Botanicus Australia.
Menkhorst, Peter.W. (Ed)
1996, Mammals of Victoria: Distribution, Ecology and Management, Oxford University Press