Yarra River bank and Trees

Posted on by Fiona Currie

City of  Yarra has engaged consulting firm Alluvium to undertake a comprehensive investigation into the slippage of the bank and the fallen or at risk trees.   A preliminary memo was tabled at the Council meeting of 30th July about the Tree Collapse and bank slumping.  Alluvium will be undertaking further investigations on the cause and source of the water in the coming weeks, with a second report on the preliminary findings of their expert group to be presented to the next Council meeting on 13th August.

More detail is available on the Council Website https://www.yarracity.vic.gov.au/news/2019/07/31/update-on-trees-at-alphington-paper-mill-site

The memo tabled by Alluvium at the Council meeting reported the findings of a number of arborist reports on the two trees within and next to the area of collapse on the bank.  The majority of  these reports recommended the removal of Tree 1, and the monitoring and retention of Tree 2.  The memo also provided the following recommendations to Council.

  • The existing trees at the site be photographed as a record of the current riparian vegetation for the site. This record can inform the future vision for the site and ultimate landscape plans
  • Tree T1, is considered to be at imminent probability to collapse ( this could be at any time in the next few months) and should be removed to reduce the future risk to public safety and bank damage.  If the tree is removed Alluvium recommend that the stump and root plates must be retained to reduce damage to the bank and provide ongoing soil stability
  • Tree 2: … The tree appears to be outside the zone of the existing tension cracks. Alluvium suggest that the tree not be removed until such time as the bank slumping includes the tree root zone or remediation of the river bank requires it to be removed.
  • Weekly monitoring of the slump and the trees to determine if conditions change and the risk of the trees falling increases.
  • Continue to restrict access to the site to maintain public safety

Lastly Alluvium recommended that a planning permit be required by Glenvill to proceed with the removal of the tree as they deemed the risk to be not an emergency.  Council adopted this recommendation and at the meeting resolved to require a Planning Permit be sought by Glenvill.