While all of Swampscott’s beaches are open, the water quality results for this week are slightly raised compared to past tests, seemingly in part to the steady rain the town has seen this week.

According to the Massachusetts Department of Public Health, water is considered safe when bacterial levels are at or below 104 colony-forming units per 100 milliliters (cfu/100 ml).

An additional measure, the geometric mean, reflects average water quality over the past month, based on the five most recent test results. For marine beaches, the allowable geometric mean is 35 cfu/100 ml.

Beachgoers can view bacteria levels on the Department of Public Health’s interactive website, though the data is updated with a 24-hour delay.

Below are the August 20 results.

Fisherman’s Beach, tested at 8:23 a.m.

Single-Sample Bacterial Results – 74.00 cfu/100 ml

Geometric Mean Results – 14.92 cfu/100 ml

King’s Beach, tested at 8:11 a.m.

Single-Sample Bacterial Results – 86.00 cfu/100 ml

Geometric Mean Results – 11.75 cfu/100 ml

New Ocean/Eisman’s, tested at 8:35 a.m.

Single-Sample Bacterial Results – 5.00 cfu/100 ml

Geometric Mean Results – 5.74 cfu/100 ml

Phillips, tested at 8:50 a.m.

Single-Sample Bacterial Results – 10.00 cfu/100 ml

Geometric Mean Results – 5.74 cfu/100 ml

Preston, tested at 8:58 a.m.

Single-Sample Bacterial Results – 10.00 cfu/100 ml

Geometric Mean Results – 10.00 cfu/100 ml

Whales, tested at 8:29 a.m.

Single-Sample Bacterial Results – 52.00 cfu/100 ml

Geometric Mean Results – 13.91 cfu/100 ml