Following Mr Rees’ response to an analysis of data on inflow to the Brunswick Valley STP given to Byron Shire Council and councillors, I can report that the infiltration problem into the collection system during wet weather events continues, and has been a ‘standing problem with Council reports going back to 1973.’
But it has been the analysis of the data, for which I take responsibility, that signals the magnitude of the problem.
Whilst Mr Rees has yet to disclose the data on which he states that average dry weather flow into the STP is between 1,300-1,500kL/day, he does concede that recorded inflow has been 19,599kL/day in wet weather in the licensing period 27 September to 26 April 2015.
This means infiltration has been recorded at 1,407.62 per cent above dry weather of 1,300kL/day. Furthermore, of the 211 days for which inflow data was collected, 138 days or 65.4 per cent had above average dry weather flow of 1,300kL/day.
Mr Rees states that ‘The Brunswick Valley STP has been operated successfully for 5 years. The high flows due to stormwater ingress present operating challenges for staff but are manageable’.
Households within the catchment area of the Brunswick Valley STP, one of the wettest areas in NSW, should not be confident of this position.
Inadequately treated bio-solids have been spread signalling a plant that is hydraulically overloaded during wet weather.
Infiltration into the collection system, because of its degraded state, cannot be solved unless it is replaced.
The alternative is to shorten the life expectancy and standard of performance of the $30 million STP by continuing to work it beyond what it was designed.
Patricia Warren, Brunswick Heads