Lake Ginninderra

• Location
• Description of facilities
• Lake uses and values
• Potential hazards associated with the facility
  

Location

Lake Ginninderra is located on the Ginninderra Creek adjacent to the Belconnen Town Centre. Lake water comprises the stormwater discharge from urban and rural areas. It has a catchment of 9800 ha, including Aranda, Macquarie, Cook, Bruce, Belconnen, McKellar, Giralang, Kaleen in the eastern areas of Belconnen and from the new town of Gungahlin.

Description of facilities

A brief description of the management zones referred to below can be found at Lakes and Ponds. A more detailed description can be found in Part B Planning Framework of the Canberra Urban Lakes and Ponds Plan of Management.

The lake was established in 1974 with the construction of Ginninderra Drive embankment over Ginninderra Creek. The lake has a surface area of 105 ha and an average depth of 3.5 m. The lake has a U shape, forming an extensive central peninsula. The Lake’s eastern arm comprises the inflow of Ginninderra Creek, from Giralang down past the naval station to the southern tip of the peninsula. This area (zone 1 type in the upstream reaches, zone 2 upstream of the Ginninderra Drive Bridge, and zone 3 downstream of the bridge) comprises extensive wetland and bird habitat for much of its length.

The southern end of the lake (or base of the U) adjacent to the Town Centre comprises a deeper zone, much of it with formal walls on its southern side. This area is designated as zone 2 type area. The location of a reduced water quality zone 2 downstream of a zone 1 is the result of polluting discharges from the Benjamin Way and Eastern Valley Way drains at the southern end of the Lake.

John Knight Memorial Park is a District Park located on the south eastern side of the Lake. It connects the Lake into the park landscape by way of vistas, an island and walkways, and by use of lake water to create an attractive ornamental pond and waterway through the park.

The Lake’s western arm from just downstream of the police jetty to the dam wall is an open and deep area, having higher water quality and vistas (zone 3 type).

Overflow from the lake is via a non-controlled spillway weir through a multi-celled concrete culvert chute located at the right abutment of the Ginninderra Drive embankment.

Construction works were undertaken in 2004 for two purposes. Firstly to increase the holding capacity of the Lake should extreme flooding occur, and secondly to add a secondary spillway on the left abutment.

A gross pollutant trap (GPT) and small pond are located on the northern inlet end, providing an important facility for intercepting and limiting litter discharged to the lake, as well as an extension of the wetland habitat zone. The Eastern Valley Way GPT and Emu Bank Pond at the southern end of the Lake similarly serves to intercept significant amounts of litter discharged from Eastern Valley Way drain.

A cycleway/walkway has been constructed around the full periphery of the lake, linking in with the Belconnen cycleway network at a number of locations.

Lake uses and values

Lake Ginninderra was originally designed as a setting for the Town Centre and a recreation and landscape feature for the Belconnen community. The natural character of the Lake, its foreshores and associated conservation values are greatly valued by the Belconnen community. The lake is also a popular recreation facility, supporting swimming, canoeing, sailing, fishing and walking.

Swimming areas are located within zone 3 areas (just downstream of the Ginninderra Drive bridge on the eastern arm, and at Macdermott Place on the north western side of the lake), including the provision of toilets, barbeques and picnic tables. A boat launching ramp has been installed at Macdermott Place on the north western side and Diddams Close on the north eastern side.

Stromwater Control

The Lake provides an important stormwater detention facility, linking the Giralang, Gungahlin, Eastern Valley Way and Benjamin Way drains or waterways to the lower part of Ginninderra Ck.

It is possible for lake water to be used for irrigation (based on licensing) of the John Knight Memorial Park area, and for cooling systems within the Benjamin and Cameron Offices.

Potential hazards associated with the facility

Elevated water flow velocities in the vicinity of the Ginninderra Drive spillway at times of heavy rainfall represents a potential safety hazard. Fences and a floating boom and have been installed to exclude the public from this area.

Given their urban runoff water source, from time to time, urban lakes may be subject to health hazards such as toxic blue-green algal blooms or high faecal bacteria counts. The water quality of the lakes is monitored by health and environmental agencies, who issue public health warnings in the event of toxic blue-green algae or faecal bacteria representing a potential risk to health.

Lake edges have been gently graded along areas of deep water to avoid sudden drops which might create difficulties for small children entering the water. Exceptions to this treatment are the formal masonry walls adjacent to the Town Centre/Emu Bank area, and the police jetty.

Graded edges also ensure that the potential for the lake to become a local mosquio nuisance is minimised.

• Lake Ginninderra Foreshore Refurbishment at Emu Inlet