Friends of Grasslands
supporting native grassy ecosystems
PO Box 440
Macquarie ACT 2614
PO Box 365
Mitchell ACT 2911
DA 201936352: Molonglo 132kv transmission line relocation
Friends of Grasslands (FOG) is a community group dedicated to the conservation of natural temperate grassy ecosystems in south-eastern Australia. FOG advocates, educates and advises on matters to do with the conservation of grassy ecosystems, and carries out surveys and other on-ground work. FOG is based in Canberra and its members include professional scientists, landowners, land managers and interested members of the public.
FOG is concerned about several issues related to the corridor revegetation, weed control, and future operation of the maintenance track.
In the verge areas, notes are provided in two of the DA documents about the general plan - specifically these are in VERGE-201936352-LMPP_1-01, and in ENVMANAGE-201936352-CPCP_NOTES-01.
The intention is stated to create dryland-grass cover over the top of the restored trench. This is reasonable in concept in the road-verge areas that are currently largely covered by exotic grasses within and near road easements (but see 2. below). However, this target is too low in the area of the Buffer Zone to Kama Nature Reserve. Although the main environmental value in this buffer is the large and old, remnant Eucalypt trees, this part of the corridor is quite close to the Nature reserve and it would add environmental value if the construction plan is upgraded to restore some biodiverse native grassland character, especially in places close to the reserve fence, particularly around the proposed electrical substation. While the wheel marks on the maintenance track would not support most native plants, the track borders and banks are distinctly different, and FOG recommends consideration be given to adding natives to the revegetation, both forbs and grasses, possibly small shrubs.
Kama Nature Reserve buffer
Following on from the above point, Kama Nature Reserve is home to a number of nationally important species, including Pink-tailed Worm-lizard, critically endangered Yellow Box – Blakely’s Red Gum grassy woodlands, Natural Temperate Grasslands, and a rare remnant example of woodlands interfacing with grasslands. The importance of this area is reflected in the heritage listing of this biodiversity “hotspot”. Adequate buffer zones from urban development are essential to preserve this biodiversity, particularly given requirements for biomass management for bushfire prevention. In our view, buffers all the way around Kama NR should be 200m, not narrowing to just 70m at the southern end of the Nature Reserve.
Sadly the verge areas along Tuggeranong Parkway and William Hovell Drive are badly invaded by African Lovegrass at present. That species is going to thrive with all the disturbance that will result from the planned engineering. Special plans need to be developed to beat this transformative plant. It is not going to be sufficient to just dig, stockpile soil, then respread as many seeds of this Lovegrass reside in the soil seedbank and they will simply outcompete the dryland grass mix sown after the surface is relevelled and grass growth encouraged. At the minimum a lovegrass control programme of spraying prior to any groundwork, also disposal and replacement of the topmost 10cm of current soil is recommended. All ground disturbance will stimulate a wide range of invasive plants and again a targeted weed control programme should be planned to avoid that. Also the weed-hygiene for all construction equipment entering the corridor must be high. FOG is well aware of a project nearby, in the Pinnacle Nature Reserve, where revegetation along the Whitlam Watermain has generated a huge weed response that is currently undergoing a very aggressive (though late) control process. Lessons learned from that project include the ease with which new weed species can be imported, in the Pinnacle case likely to be from straw mulch used to stabilise the dryland-grass seeds, and the likelihood that other species (such as Paterson's curse, Ribwort Plantain, Witchgrass) explode in a revegetation corridor. The Calibre Group is actually involved in oversight of the Watermain project also, so it should be straightforward that more detail be added by Calibre to create best-practice planning of this weed control for the Molonglo 3 underground-power-cable project.
To reiterate points above, it is unfortunate that a hard track be preserved along the route forever. Surrounding land potentially is degraded by fragmenting and by any weed invasion, so all practical steps should be taken to soften and stabilise the track and to prevent and control weeds as a component in perpetuity of the underground-cable maintenance. Any mowing, trimming or equipment movement must be preceded by effective weed-prevention hygiene.
Finally, the Construction Phase note C16 in the document ENVMANAGE-201936352-CPCP_NOTES-01 states there will be "CONTROL ON ANY NOXIOUS WEED". Noxious weeds are not defined any more. In the ACT, the descriptions in 2015 legislation define Pest Plants, and Environmental Weeds and Invasive Plants are the terms now used on the Environmental and Sustainable Development Directorate website. Therefore FOG requests this Construction Note be updated and recommends that declared Pest Plants such as Serrated Tussock, African Lovegrass, St John's Wort, Paterson's Curse and Viper's Bugloss be specified for the project
6 June 2020