Bega STP Capacity Assessment and Upgrade Strategy

  • ASpect’s Client: Bega Valley Shire Council
  • Head Client: Bega Valley Shire Council
  • Plant Configuration: SBR
  • Plant Size: 5,000 EP
  • Project Value: $50k (ASpect Fee $24k)
  • Project Duration: June 2018 to December 2019

Bega STP Capacity Assessment and Upgrade Strategy (SBR), for Bega Valley Shire Council (NSW).

Bega STP is a nominal 8,500 EP STP that services the township of Bega.  The plant was constructed and operated by a private company for a period, the handed back to Bega Valley Shire Council (BVSC) in 2016.  From that time, BVSC operators reported that the plant was difficult to operate, especially during wet weather.  They had concerns that the plant capacity may be less than the 8,500 EP design capacity.  ASpect undertook a detailed and granular process capacity assessment as well as co-ordinating a hydraulic capacity assessment through its sub-contractor CEENA.  ASpect concluded that many of the process units, particularly the SBR bioreactors and sludge lagoons, were well under the nominal design capacity.  In fact, the plant had less capacity than the current loading of 5,000 EP.  The plant was only operable under dry weather conditions and, even then, only if sludge settleability was excellent.  The hydraulic capacity was also found to be lacking, risking overtopping of structures under sustained wet weather events.  ASpect and CEENA recommended a number of operational and minor capital enhancements aimed at reducing risk in the short to medium term.  ASpect also suggested a number of major upgrade strategies including a new inlet works, additional SBR reactors (or conversion to continuous flow MLE), additional sludge lagoons, plus a range of other targeted capacity increases.