Perth Seawater Desalination Plant: Rehabilitation
2007: Entrance to Class A reserve mulched, planted and rabbit proof fence installed, prior to planting.
2007: Successful weed control of Acacia longifoilio at the Buffer Lakes (midground of photo) with 2006 rehabilitation in the photo foreground.
Successful 2006 showing high density and diversity.
Healthy Anigozanthos manglesii planted in 2007.
Healthy Acacia, Banksia, Kunzea and Conostylus with tree guarding behind.
Priority 4 Dodonaea hackettiana from the 2006 planting season.
Project Environmental Management
Western
Australia
Client: Water Corporation
Services Provided by: 360 Environmental Pty
Ltd
Role: Project Environmental Manager
Contract: Fee for Time
Value of the Folio Managed: $5.8M
Duration: 2004-2007
Western Australia's Water Corporation constructed the Perth Seawater Desalination Plant, a $387 million plant and $125M of assets to deliver water to the Integrated Water Supply System (IWSS) and supplement Perth’s public supply by 17 percent. At the time of construction this is the largest desalination plant in the southern hemisphere. The PSDP was subject to an Environmental Protection Statement (EPS) level of assessment.
Among the 13 proponent and 7 Ministerial and legally binding environmental commitments were key measures to manage the marine environment of Cockburn Sound and undertake management for flora and fauna. The net environmental outcome for the PSDP and the integration assets was a positive one with offsets ranging from land purchases, a dual use path and wetland enhancement at Nicholson Road Pump Station.
Restoration and rehabilitation efforts commenced in the winter of 2006. From mid-July, seed was spread and seedlings planted and fertilised. The key areas that required restoration included:
- PSDP foredune, Kwinana;
- Pipeline route between Kwinana and Thomsons Lake;
- Thomsons and Kogolup Lakes, Beeliar Regional Park;
- Bartram Road Buffer lakes, Success;
- Mather Reserve, Banjup;
- Wetland Area near Bartram Road and within Jandakot Regional Park; and
- Wetland at the Nicholson Road Pump Station in Forrestdale.
The seed spreading, seedling planting and fertilising was undertaken by a not-for-profit organisation, who competitively won the tender. The rehabilitation areas were extremely diverse ranging from the coastal primary dune in Kwinana to inland wetland areas including an area within Thomsons Lake Nature Reserve, an internationally recognised wetland providing a habitat and refuge for water birds.
Seedlings were supplied from five different nurseries. Seed was collected and sourced for specific areas. Provenance-correct seed was collected from the A Class Reserve (with DEC approval). This seed was then used to grow provenance seedlings for the restoration between Thomsons Lake. The 2005/2006 cool summer naturally prevented a generous seed set. In order to sustainably collect the required volumes of seed, collection will occur over two seasons.
As part of the project, the Water Corporation prepared a Rehabilitation Management Plan which was finalised with input from the (then) Department of Conservation and Land Management and the Wetlands Conservation Society. Ongoing monitoring was incorporated to ensure compliance criteria were met.