Coffs Harbour City Council
Ocean beaches: Emerald, Jetty. Creeks and Estuarine: Red Rock, Arrawarra, Boambee, Bonville, Coffs, Moonee. Coastal lakes: Woolgoolga Lake, Hearns Lake. Ocean pools: Sawtell Rockpool. For details see (08472Coffs.pdf, 592 KB)
Local government area description
Coffs Harbour City Council is situated on the NSW north coast, approximately 550 kilometres north of Sydney. The council area covers 51 kilometres of coastline, stretching from Arrawarra in the north to Bundagen in the south and includes 21 beaches and 14 major coastal creeks. The Solitary Islands Marine Park encompasses much of the council’s coastal waters.
The population of the area is approximately 70 000 and growing at a rate of 1.6 per cent each year. Approximately 91 per cent of the population reside in towns along the coast. The council area is interspersed with sparsely populated rural areas, and approximately half is covered by forest.
Average rainfall is 1700 mm a year and surface runoff is more than double the average for coastal NSW. Agriculture is very important to the region’s economy-particularly beef and dairy farming, with extensive banana cultivation in the ranges. Industrial activities are generally small in scale (Coffs Harbour City Council 2000a, 2000b).
Program outline
Eleven swimming locations were monitored in the Coffs Harbour City Council area: two ocean beaches, one rockpool, one estuarine swimming location, two coastal lakes and five creeks. These sites were also monitored during the 2002–2003 and 2006–2007 summer swimming season (DEC 2004b, DECC 2007).
Enterococci samples were collected between November 2007 and February 2008, the four busiest months of the summer swimming season. Compliance was assessed against the NHMRC (1990) swimming water quality guidelines. It should be noted that the five samples necessary to calculate compliance were not collected in all months. In months when less than four samples were collected, compliance could not be determined.
Rainfall
Rainfall data presented in the timeseries plots were obtained from the Bureau of Meteorology gauges at Yamba, Woolgoolga and Coffs Harbour. Rainfall for each site is from the closest rain gauge.
Ocean beaches
Guideline compliance
A high level of compliance with NHMRC (1990) swimming water guidelines was recorded at both ocean beaches. Emerald and Jetty beaches were suitable for swimming in the two months between November 2007 and February 2008 in which sufficient samples were collected to calculate compliance (Figure 5). For details see (08472Coffs.pdf, 592 KB)
Response to rainfall
Enterococci levels were generally low throughout the monitoring period. Slightly elevated results were recorded at Emerald Beach in response to rainfall.
Rockpools
Guideline compliance
A high level of compliance with NHMRC (1990) swimming water guidelines was recorded at Sawtell Rockpool (Figure 5). The site was suitable for swimming in both months of the summer season in which sufficient samples were collected to calculate compliance (Figure 5). For details see (08472Coffs.pdf, 592 KB)
Response to rainfall
Enterococci levels were generally low throughout the monitoring period, with only two elevated results recorded in response to heavy rainfall.
Coastal lakes
Guideline compliance
Woolgoolga Lake and Hearns Lake both passed the NHMRC (1990) swimming water guidelines in only one of two months between November 2007 and February 2008 in which sufficient samples were collected to calculate compliance (Figure 5). For details see (08472Coffs.pdf, 592 KB)
Response to rainfall
Levels of enterococci frequently exceeded the geometric mean guideline limit at Woolgoolga Lake and Hearns Lake, with very high values recorded on a number of occasions in response to rainfall.
Creeks and estuarine locations
Guideline compliance
A high level of compliance was recorded at Red Rock and Coffs Creek which passed NHMRC (1990) swimming water guidelines in both months in which sufficient samples were collected to calculate compliance (Figure 5). This result was similar to the previous season’s when both sites complied with guidelines in all four months between November 2006 and February 2007 (DECC 2007).
Arrawarra Creek, Moonee Creek and Boambee Creek complied in only one of the two months. All sites failed in February 2008 owing to elevated levels of enterococci.
The lowest level of compliance was recorded at Bonville Creek which failed to comply with swimming guidelines in both months in which sufficient samples were collected to calculate compliance (Figure 5). For details see (08472Coffs.pdf, 592 KB)
Response to rainfall
Although low levels of enterococci were often recorded at Coffs Creek throughout the monitoring period, some high results were recorded in January and mid-February 2008 in response to heavy rainfall.
Elevated enterococci levels were frequently recorded at all other creeks in response to heavy rainfall. Monitoring conducted during summer 2002–2003 under the BPPP and during 2006–2007 also found high levels of bacteria at these sites following rainfall (DEC 2004a, DECC 2007).
Figure 5: Summary of compliance with NHMRC (1990) microbiological guidelines for swimming at Coffs Harbour City Council swimming sites during the 2007–2008 summer swimming season
Page last updated: 26 February 2011
