1 Distribution of Enterococcus Concentrations

1.1 All Samples

This section summarizes the distribution of all enterococcus samples. It only includes routine samples and thus excludes all resamples.

This figure shows the histogram of all routine samples on a log-scale. The vertical lines show the 70 and 104 limits. The distribution is uni-modal, the large change at 10 MPN/100mL is due to the detection limits.

This figure shows the same data, but on a linear scale and only including samples with ENT < 200 to focus on the lower range. Again, the majority of routine samples are at or below the detection limit of 10 MPN/100mL.

Question: What fraction of all routine samples are between 70 and 104?

Answer: 3.71%

This table shows the fraction of routine samples <70, between 70-104, and >104.

Range Percent
<=70 87.5%
70-104 3.7%
>104 8.8%

Question: If a routine sample is greater than 70 MPN/100mL, what is the probability it is also > 104?

Answer: 70.4%

This table shows the fraction of samples between 70-104 and >104 based only on samples with concentrations <70. This shows that out of all samples greater than 70 MPN/100mL, about 70% are also above 104, and 30% are between 70 and 104.

Range Percent
70-104 29.6%
>104 70.4%

1.2 By Beach

In this section, the data are grouped by beach and thus may include more than one sampling site.

This figure shows the total number of routine samples in each category (<70, 70-104, >104).