Provision of Stage 1 Construction - Neil McDougall Lake Water Sensitive Urban Design

⁠⁠⁠Background

The City of South Perth (City) invites suitably qualified organisations to submit tenders for the Provision of Stage 1 Construction - Neil McDougall Lake Water Sensitive Urban Design

The scope of works consists of stage 1 construction only and includes the provision of civil, electrical, mechanical and landscaping works.
Neil McDougall Lake is a highly modified natural wetland located in Como suburb of the City of South Perth. It was formerly part of a natural chain of wetlands and was probably seasonally inundated.

The original 'swamp' was deepened and modified in the 1960's to form a stormwater compensating basin and to create a permanent lake. In 1995, the lake was deep dredged to maintain the permanent water levels due to falling groundwater levels associated with a drying climate.

At present the lake acts as an infiltration basin and receives stormwater from four catchments (~72 ha in total) via direct discharge. The lake also intercepts groundwater, which flows through it in a south westerly direction towards the Swan River.

The lake has significant environmental values and is visited and used by a variety of birds, as well as the Western long-necked tortoise. The lake is also highly valued by the local community and is used extensively for passive and active recreation.

For a prolonged period, the water quality of the lake has been below standard. This has led to a prolific growth of duckweed and algal blooms especially during summer period. A range of factors have contributed to the decline in water quality, the dominant ones being:

1. Direct stormwater inputs from large catchments
2. Poor water movement (flow) within the lake, particularly during non-rainfall periods

To manage water quality problems at Neil McDougall Park Lake the City completed a number of studies and developed a construction plan for an integrated remediation solution with a focus on water sensitive urban design that includes the construction of sedimentation zones, vegetated filtration zones and a treatment wetland to treat stormwater inflows to the Lake and recirculated Lake water.

This remediation solution consists of the following 3 construction stages:

Stage Stage components

Stage 1
- Work Package 4 - Lake Circulation Works
- Work Package 5 - Electrical Services Works
- Work Package 1 - Catchment B (SDB1, SFW1, SFW2, SSFW1 and Portion of Lake Fringe Planting)

Stage 2
- Work Package 2 - Cathment C (SDB2, FW2 and Portion of Lake Fringe Planting)

Stage 3
- Work Package 3 - Cathment D (SDB3, FW1 and Portion of Lake Fringe Planting)

All works shall be carried out in accordance with the City of South Perth Request for Tender, General Conditions of Contract, Technical Specifications Report, the Drawings and to the satisfaction of the Superintendent.

Pumping and pressure system works shall be carried out in accordance with Appendix 3 of the Technical Specifications Report. Electrical works shall be carried out in accordance with Appendix 4 of the Technical Specifications Report.

The City

The City of South Perth is a medium sized metropolitan local government authority located 4 kilometres across Perth Water from Perth City.
The City of South Perth covers the suburbs of South Perth, Kensington, Como, Manning, Karawara, Waterford and Salter Point. The district is primarily residential; however, important local industries include professional offices, educational institutions, tourism and golf courses.

The City of South Perth is guided by its Sustainability Strategy, systems and practices, which commits to identifying and minimising harmful sustainability impacts of the City's operations. This commitment to sustainable practice extends to the City's suppliers and contractors wherever possible. Information about the City's sustainability programs is available on the City's website.

The Organisation

The City's Civic Centre is located on the corner of Sandgate Street and South Terrace, South Perth. The City also operates from other locations including its Operations Centre 199 Thelma Street, Como.

The City's website www.southperth.wa.gov.au

The organisation has the responsibility for the good government of the City of South Perth. The City must perform its functions in accordance with the Local Government Act (WA) 1995.

The City has the responsibility for the orderly planning of the district under the Town Planning and Development Act (WA) 1928.

The City also has statutory obligations under a wide range of state and federal legislation.