Land based sources of faecal contamination arising from the islands as well as the adjacent coasts of France was considered unlikely to significantly impact the bacteriological quality of scallops harvested from within the offshore fishery areas.

The nearest land based sources of faecal contamination to the fishery areas are those arising on Jersey itself. Sewage discharges and land runoff carrying faecal bacterial are concentrated mainly along the south and east shores of the island, though there are potentially smaller discharges elsewhere on the island. The only sewage discharges directly to the fishery waters would come from boat and ship traffic. Untreated sewage wastes may be discharged from ships directly to sea more than 12 nautical miles (22.2 km) from land and treated (comminuted and disinfected) wastes may be discharged at least 3 nautical miles (5.6 km) from land. These might be predicted to most likely occur along regular shipping routes and more often during periods of higher activity; however due to the large tidal ranges and flows in the area, these discharges are likely to be highly diluted before reaching the seabed and the scallops.

Samples were provided from four areas (identified as north, east, south, and west) within Jersey's territorial waters. Faecal indicator (E. coli) results confirmed very low levels of faecal contamination at the seabed where the samples were collected. However, it must be noted that the sampling period was limited and a longer dataset would be needed to confirm that these results were stable and to assess any seasonal or temporal variability.

Little spatial variability was found. Most samples tested were below the lower limit of detection of the test used (<18 MPN E. coli/100g flesh and intravalvular liquid) and those with quantifiable results were close to this level. 

Samples taken from the area identified as North did not map geographically within the offshore fishery area, but within 1.5 km of the north shore of Jersey. This survey only addresses the offshore harvesting of scallops and therefore inshore areas cannot be represented by the sampling plan recommended here.

It was recommended that a single monitoring point be established within the Southern fishery area, close to the ferry route between St Malo and Jersey, that could be used to represent the East, South, and West areas. A sampling tolerance of 2 km is recommended to ensure sufficient scope for obtaining regular monitoring samples. Sampling frequency should be monthly until a sufficient monitoring history can be obtained to assess reducing the frequency. Details of the recommended sampling plan are given on page 1 of this report.