Public notice

ORC planning broader flood work programme for Mosgiel’s Silver Stream

Wednesday 24 April 2024

Our maintenance work programme on Silver Steam near Mosgiel will resume next month and be completed by the end of June and planning for a broader programme of flood works is already in the pipeline.

ORC’s Manager Operations Gavin Palmer says programme of maintenance work along Silver Stream - between Wingatui Road and the confluence with the Taieri River — includes vegetation control activities on the banks, formed beaches and islands.

Dr Palmer acknowledges recent concerns raised by the community around the Silver Stream.

“Whilst planned works are to be completed by the end of June 2024, ORC is also developing a broader programme of works to address restoration of Silver Stream’s channel capacity,” Dr Palmer says.

ORC ’s Draft Infrastructure strategy proposes $829,000 be allocated to Silver Stream Capacity Maintenance.

The funding would be spread across years 1 to 4 of the strategy - being the 2024/25 to 2027/28 financial years — with ongoing capacity maintenance work incorporated as a routine activity from the 2028/29 financial year onwards.

The broader programme of works is currently in the development stage with, ecological assessments and consenting activities underway and hydrological analysis planned to start within the next few weeks, he says.

Dr Palmer notes that resource consent is required for some forms of the vegetation work and for any gravel or sediment removal.

The timing of the implementation of this broader work programme work will align with the 2024—2034 Long-Term Plan, when it is considered by council. Public submissions on the Long-Term Plan are currently open until Sunday, 28 April.

Silver Stream Capacity Maintenance 

  • The project seeks to restore balance to the Silver Stream’s hydraulic capacity under today’s environmental considerations. 
  • Site investigation to be underway shortly, identifying areas where capacity can be improved, this includes conducting aerial surveys to map the channel. 
  • Consenting will be required to undertake in stream works and sediment extraction. Planning for consenting is underway. 
  • Project to be staged in line with ecological considerations. Implementing the improvement works to deliver benefits as early as possible. 


Silver Stream Current Routine Maintenance Activities

  • Flood bank inspection (these are visual inspections with defects reported), outcomes from the inspections may contribute to annual work schedules.
  • Waterway inspection (visual inspection defects reported), outcomes from the inspections may contribute to annual work schedules.
  • Repairs to banks and structures (as identified during inspection).
  • Rabbit control (Annual Programme).
  • Pest plant control (Annual Programme).
  • Fertilising (when required).
  • Mowing (Annual Programme).
  • Vegetation maintenance (Annual Programme).
  • Asset Maintenance i.e. structures, pump Station (Annual Programme)