Location
The Gungahlin pollution control ponds, comprising Gungahlin Pond and Yerrabi Pond, are located upstream of Lake Ginninderra. Further ponds/wetlands are to be constructed, including Moncrief Pond on the western arm of Ginninderra Creek upstream of Gungahlin Pond, and the Gungahlin wetlands on Gungaderra Creek (tributary of Ginninderra Creek). The pond waters are comprised of stormwater discharge from urban and rural areas. Gold Creek Pond has been privately constructed and is integrated into the Gold Creek Golf Course.
Pond
| Pond details | Catchment | Catchment area | Suburbs |
Gungahlin Pond | Area 25.4 ha
Average depth 3.0 m | Ginninderra Creek | 5,000 ha | Nicholls, Palmerston |
Yerrabi Pond | Area 10 ha
Average depth 2.7 m | East Ginninderra Creek | 2,060 ha | Amaroo, Harrison, Forde, Throsby |
Moncrief Pond | (tbc) | Upper Ginninderra Creek | 1,500 ha | Moncrief, Taylor |
Gungahlin Wetlands | (tbc) | Gungaderra Creek | 800 ha | Franklin, Mulanggari |
Description of facilities
Gungahlin Pond was constructed in 1989 and Yerrabi Pond was constructed in 1994 as part of the Gungahlin town development. Gungahlin Pond's primary spillway comprises a drop structure and culvert through the embankment. The secondary spillway, an earth and vegetated channel, is constructed on the eastern abutment of the embankment.
Yerrabi Pond is formed by the Mirrabei Drive embankment across East Ginninderra Creek. The primary spillway comprises a drop structure and culvert through the embankment. The secondary spillway comprises a concrete weir and chute on the western abutment of the embankment
Both Gungahlin Pond and Yerrabi Pond have extensive open water areas, with limited macrophyte zones around their margins. Both ponds have gross pollutant traps installed on their inlets to limit litter discharge.
Lake uses and values
Both ponds were constructed as part of the Gungahlin Stormwater Pollution Control and Belconnen Flood Protection Strategy. Refer to Gungahlin Environmental Impact Statement 1988.
The ponds and other land development controls have been designed to limit pollutant loading on Lake Ginninderra to levels consistent with water pollution control, aesthetic and recreational use objectives. Both ponds include provision for substantial temporary stormwater storage during periods of high rainfall.
The ponds were also designed as landscape and passive recreation facilities while maintaining acceptable in-pond water quality.
Potential hazards
Heavy rainfall represents a potential safety hazard due to elevated water flow.
Lake edges have been gently graded along the areas of deep water to avoid sudden drops.
Note
This section was written by the ACT Government in collaboration with Ian Lawrence of the Cooperative Research Centre for Freshwater Ecology.
