Overflows into the river occurred for a total of 615 hours across that two-year period, some occurring simultaneously from different pumps inside the station.

Laboratory testing conducted after a number of overflow events on October 27, 2014, showed thermotolerant (faecal) coliform levels were at 200,000 colony forming units per 100 millilitres, enterococci levels were at 62,000cfu per 100ml, and E. coli levels at 160,000cfu per 100ml. 

According to the National Health and Medical Research Council an enterococci level of over 500cfu per 100ml carries a “ significant risk of high levels of illness transmission” for beaches.

The Tasmanian Laboratory Service states on their website that the thermotolerant coliform/E. coli count for secondary water contact should not exceed 1000cfu per 100ml for a random sample. 

Overflows occurred on 61 separate days in 2014, one lasting for more than 13 hours, and two lasting over 10 hours. Over 90 overflow events occurred on April 29, 2014, during which the Bureau of Meteorology measured 32 millimetres of rainfall over a two-day period. 

One TasWater employee said the eight pumps in the new station which recorded overflows were classified as stormwater pumps, however “when the (pumps) are running it will be stormwater and some waste water.”

The Right to Information officer was unable to provide data on the volume of wastewater that entered the river during the overflows, however TasWater asset strategy manager Andrew Truscott said volumes could be calculated if needed.

The Margaret Street stations are combined stormwater and sewage systems. 

It is understood that Tasmania’s seven federal Liberal MPs have lobbied Prime Minister Malcolm Turnbull to provide funds to upgrade the state’s ageing sewerage infrastructure in Tuesday’s Federal Budget.