Historical News

Week of November 20 - 26, 2022

Water Column Clarity

​Water clarity was measured at seven locations in the Providence River and Seekonk River estuaries on November 23. Conditions leading up to the survey were dry, with no precipitation recorded at TF Green in the five days prior. Secchi depth averaged 3.1 meters, compared to 3.2 meters on the previous survey (November 17). The lowest clarity this week (2.2 meters) was measured at Pomham Rocks, while the greatest clarity (4.7 meters) was measured at Conimicut Point. There was a general north-to-south gradient of increasing water clarity among the sites this week. ​

Week of November 27 - December 3, 2022

R/V Monitor's Blog

On Wednesday, November 30th, the crew of the R/V Monitor was out on the upper Bay collecting nutrients samples, taking Secchi Disk water clarity measurements, conducting water column profiles using a profiling sonde, and conducting real-time surface mapping of water quality parameters, including dissolved oxygen, chlorophyll, water temperature, salinity, and pH, all in an effort to document water quality improvements associated with NBC construction projects. Jeffrey captained the boat while monitoring professionals Fern, Gerard and Steve collected the samples and data. It was a sunny and brisk day with no wind and calm waters. The featured photo from our archives shows ProvPort from the east.

11-2-22 ProvPort.jfif




Week of November 20 - 26, 2022

Bacteria Sampling

​On November 23, twenty stations were sampled for fecal coliform bacteria in the Providence and Seekonk Rivers.  Five of these stations were also sampled for enterococci bacteria. No precipitation was recorded at TF Green in the five days prior to sampling. 

Overall, bacteria counts in the Providence River were higher this week than during the previous sampling event on November 9 (geometric means of 11 MPN/100 mL and 6 MPN/mL, respectively); ​The Seekonk River was not sampled on November 9. Fecal coliform counts were higher in the Seekonk River sites than in the Providence River sites (geometric means of 84 MPN/100 mL and 11 MPN/100 mL, respectively). The maximum counts (240 MPN/100 mL) were measured at Phillipsdale Landing and Narragansett Boating Center in the Seekonk River.
 
Enterococci results had an overall geometric mean of 13 MPN/100 mL. Enterococci results ranged from non-detect at four sites (South FP East, Gaspee Point, Conimicut Point, and one of the Phillipsdale Landing duplicates) to 31 MPN/100 mL at the Point St. Bridge site.

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​ct1​​​​​

Geome​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

Shellfishing

Geometric 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.​​​​

Week of November 27 – December 3, 2022

Surface Mapping

​Data were collected on November 29, 2022, while the R/V Monitor was underway collecting nutrient samples in the Providence River estuary. The average chlorophyll concentrations were good in the areas surveyed. From north to south, average chlorophyll concentrations were as follows: Upper Providence River (0.46 µg/L), Edgewood Shoals area (0.46 µg/L), Pawtuxet River area (0.49 µg/L), and Lower Providence River (0.80 µg/L). Overall, chlorophyll ranged between 0.12 and 1.21 µg/L with an overall average of 0.57 µg/L. The chlorophyll data from this date are presented in the map below:​

Dataflow 2022-11-29_small.jpg

Week of November 20 – November 26, 2022

Surface Mapping

​Data were collected on November 23, 2022, while the R/V Monitor was underway collecting bacteria samples in the Providence and Seekonk River estuaries. The average chlorophyll concentrations were good in the areas surveyed. From north to south, average chlorophyll concentrations were as follows: Seekonk River (0.51 µg/L), Upper Providence River (0.58 µg/L), Edgewood Shoals area (1.04 µg/L), Pawtuxet River area (0.51 µg/L), and Lower Providence River (0.41 µg/L). Overall, chlorophyll ranged between 0.05 and 1.64 µg/L with an overall average of 0.55 µg/L. The chlorophyll data from this date are presented in the map below:​​

Dataflow 2022-11-23_small.jpg

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