June 4-10, 2023

​On June 7, twenty stations were sampled for fecal coliform bacteria in the Providence and Seekonk Rivers.  Five of these stations were also sampled for enterococci bacteria. Precipitation in the five days prior to sampling totaled 0.14 inches as recorded at TF Green.​

The geometric mean of fecal coliform results for all sites was 17 MPN/100 mL compared to 73 MPN/100 mL on May 24. Overall, bacteria counts were lower in the Seekonk River and Providence River this week than during the previous sampling event on May 24. Fecal coliform counts were geomeans of 41 MPN/ 100 mL in the Seekonk River and 12 MPN/ 100 mL in the Providence River. The maximum count (210 MPN/100 mL) was measured at Point St. Bridge in the Providence River.

Enterococci results had an overall geometric mean of 15 MPN/100 mL. Enterococci counts ranged from non-detect at South FP East and Gaspee Point to 52 MPN/100 mL at Point St. Bridge.

The table below lists the Rhode Island bacteria standards for primary contact and shellfishing established by the Rhode Island Department of Environmental Management (RIDEM). RIDEM defines primary contact as any recreational activities in which there is prolonged and intimate contact with water, involving considerable risk of ingesting water (e.g., swimming, diving, water skiing and surfing). Please note that the RIDEM bacteria standards are provided here for informational purposes only and are not intended to indicate official state compliance with primary contact or shellfishing standards.

Summary of Rhode Island Bacteria Standards for Saltwater Primary Contact and Shellfishing

 ​​Fecal Coli​fo​rmEnterococci
Primary Con​​​t​a​c​t1​​​​​Geom​e​tric me​a​n​ ≤50 MPN/1​​00​ mL
<10% ​o​f​ samples >400 MPN/100 mL
Geom​etric mean ≤35 colo​nies/100 mL​
All sa​mples ≤104 colonies/100 ​​mL2
ShellfishingGeometric mean ≤14 MPN/100​ mL
<10% of samples >49 MPN/100 mL3​
NO ENTEROCOCCI CR​ITERIA

1Fecal coliform primary contact criteria app​lied only when adequate enterococci data are not available; 2Single sample maximum criterion for determining beach swimming advisories at designated beaches as evaluated by the Rhode Island Department of Health; 3For a three-tube decimal dilution

Table adapted from Rhode Island Water Quality Regulations (250-RICR-150-05-1)​; see regulations for complete details.​​​​​​​​​​​

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