Historical News

May 20, 2024

R/V Monitor's Blog


Today a new MET Sensor Assembly was installed on the recently deployed Bullocks Reach Buoy.  The assembly includes a weather station that can monitor wind speed, humidity, air pressure, and temperature.   The buoy was deployed on May 14th and staff have been diligently working to get the buoy up and running for the 2024 Fixed Site Monitoring Season.

Bullocks Buoy 2024.JPG

May 1, 2024

Phytoplankton Sampling

​Phytoplankton samples were collected on May 1, 2024 at Bullock Reach and analyzed in the laboratory shortly after collection. It was a cold and breeze day on Narragansett Bay with cloudy conditions. The qualitative tow net sample had a long filtration time, and the filtrate was a reddish brown and slightly cloudy.

The analysis of the quantitative whole water sample revealed a total of 4,006,000 cells per Liter. The micro flagellates were found at 24,000 cells/L. The most predominant phytoplankton genus was Skeletonema spp. at 1,646,000 cells/L. Other representative genera include Thalassiosira spp., Leptocylindrus spp., and Chaetoceros spp. This week's featured image is Eucampia spp. (200x phase contrast), a type of diatomic phytoplankton that is often found in the North Atlantic Ocean. This genus is often found in a curved form and in helical chains. This diatom is yellow-brown in color with numerous green chloroplasts.
2024_05_01_Eucampia_spp_200xPC.JPG

April 16, 2024

Phytoplankton Sampling

​Phytoplankton samples were collected on April 16, 2024 at Bullock Reach and analyzed in the laboratory shortly after collection. It was a sunny and calm day on Narragansett Bay. Some lions mane jellyfish were detected. The qualitative tow net sample had a fast filtration time, and the filtrate was a clear yellow-brown color. 

The analysis of the quantitative whole water sample revealed a total of 1,038,000 cells per Liter. The micro flagellates were found at 32,000 cells/L. The most predominant phytoplankton genus was Skeletonema spp. at 529,000 cells/L. Other representative genera include Leptocylindrus spp. and Chaetoceros spp. Actinoptychus spp. is a type of photosynthetic phytoplankton belonging to the centric diatom group. It is found in Narragansett Bay and widely distributed in spring and fall. It is identified by six radial sectors. The raised sectors can appear to look like a hazard sign, as seen in this 200x phase-contrast image.​

2024_04_16_Actinoptychus_spp_200xPC.JPG

April 24, 2024

Bacteria Sampling

On April 24th, twenty stations were sampled for fecal coliform bacteria in the Providence and Seekonk Rivers; five of these stations were also sampled for enterococci bacteria. In the five days prior to sampling, precipitation totaled 0.28 inches as recorded at TF Green. Overall, bacteria counts were lower in both the Seekonk and Providence Rivers this week than during the previous sampling event on March 27th, likely because of the drier weather leading up to sampling. 

Fecal coliform counts were higher in the Seekonk River sites than in the Providence River sites (geometric means of 59 MPN/100 mL and 7 MPN/100 mL, respectively). The maximum count (430 MPN/100 mL) was measured at Point St Bridge. 

Enterococci results had an overall geometric mean of 14 MPN/100 mL. Enterococci counts ranged from <10 MPN/100 mL at South FP East, Gaspee Point, and Conimicut Point to 41 MPN/100 mL at Phillipsdale Landing.

The next scheduled sampling date is May 8.

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 
 ​
​Fec​al Coli​fo​rmEnterococci
Primary Con​​​t​a​c​t1​​​​​

Geom​e​tric ​m​e​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.​​​​​​​​​​

March 27, 2024

Bacteria Sampling

On March 27th, twenty stations were sampled for fecal coliform bacteria in the Providence and Seekonk Rivers; five of these stations were also sampled for enterococci bacteria. In the five days prior to sampling, precipitation totaled 3.12 inches as recorded at TF Green. Overall, bacteria counts were higher in both the Seekonk and Providence Rivers this week than during the previous sampling event on March 13th, likely because this event had less time in between the rainfall and sampling. 

Fecal coliform counts were slightly lower in the Seekonk River sites than in the Providence River sites (geometric means of 51 MPN/100 mL and 66 MPN/100 mL, respectively). The maximum count (430 MPN/100 mL) was measured at both Collier Point Park and Off FP Outfall. 

Enterococci results had an overall geometric mean of 26 MPN/100 mL. Enterococci counts ranged from 20 MPN/100 mL at South FP East to 41 MPN/100 mL at both Phillipsdale Landing and Gaspee Point.

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 
 ​
​Fec​al Coli​fo​rmEnterococci
Primary Con​​​t​a​c​t1​​​​​

Geom​e​tric ​m​e​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.​​​​​​​​​​

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