Historical News

Week of November 25 - December 1, 2018

R/V Monitor's Blog

​On Wednesday, November 28th, the crew of the R/V Monitor was out on the upper Bay collecting bacteria samples, taking Secchi Disk and Par sensor water clarity measurements, conducting water column profiles using the Seabird instrument, 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.  Sara captained the boat while monitoring professionals Fern and Mike collected the samples and data.  It was a cool day with winds out of the south, making the water choppy.  Below is a photo taken this day of Phillipsdale landing in the Seekonk River, where NBC's fixed site monitoring station is located.

11-28-18 Phillipsdale.jpg 

Week of November 25 – December 1, 2018

Bacteria Sampling

Twenty stations were sampled for fecal coliform bacteria in the Providence and Seekonk Rivers on November 28, 2018; five of these stations were also sampled for enterococci bacteria. Heavy precipitation occurred in the three days prior to sampling, totaling 2.78 inches. Over an inch of rainfall was recorded on both November 25th and 26th.

The fecal coliform geometric mean increased from the previous sampling to 482 MPN/100 mL. Fecal coliform concentrations were higher in the Providence River (geometric mean: 593 MPN/100 mL) than in the Seekonk River (geometric mean: 310 MPN/100 mL). The maximum fecal coliform concentration of 2300 MPN/100 mL was measured in the Providence River at Gaspee Point. The greatest fecal coliform value in the Seekonk River, 930 MPN/100 mL, occurred at the Narragansett Boating Center and in one of the Phillipsdale Landing samples. Geometric mean results indicate both rivers exceeded primary contact and shellfishing standards.

The overall enterococci geometric mean was 347 MPN/100 mL. Concentrations ranged from approximately 252 MPN/100 mL at Phillipsdale Landing (geometric mean of two duplicates) to 703 MPN/100 mL at Point Street Bridge. The geometric mean of all results exceeded the state primary contact standard.

Please note: the results of NBC's fecal coliform and enterococci monitoring are for informational/research purposes only and are not intended to suggest official state compliance with bathing or shellfishing standards.

Week of November 25 - December 1, 2018

Surface Mapping

​Data was collected on November 28, 2018 while the R/V Monitor was underway collecting bacteria samples and performing vertical profiles in the Providence and Seekonk River estuaries. The chlorophyll concentrations were low in areas surveyed. From north to south, average chlorophyll concentrations were as follows: Seekonk River (1.98 µg/l), Upper Providence River (1.76 µg/l), Edgewood Shoals area (1.29 µg/l), Pawtuxet River area (1.34 µg/l), and the Lower Providence River (1.11 µg/l). Overall, chlorophyll ranged between non-detectable and 2.80 µg/l with an overall average of 1.61 µg/l. The chlorophyll data from this date is presented in the map below:

Dataflow 2018-11-28_small.jpg 

Week of November 18 – 24, 2018

Water Column Profiles

Water column profiles were measured at six sites in the Seekonk and Providence Rivers on November 21, 2018. Though a total of 1.14 inches of precipitation was recorded in the five days prior to sampling, only light rain (0.2 in) occurred the day before sampling. India Point Park, Pomham Rocks, and Edgewood Yacht Club displayed the greatest degree of stratification, while stratification was not evident at Pawtuxet Cove.

Highest surface water salinity measurements occurred at Conimicut Point and Bullock Reach, where salinity was approximately 23 psu. Lowest surface salinity (5.8 psu) was observed at India Point Park. Bottom salinity ranged from 10.4 psu at Pawtuxet Cove to 30.9 psu at Conimicut Point. The coldest surface water temperature was observed at India Point Park, at 6.5°C, while the greatest surface water temperature (9.5°C) occurred at Bullock Reach. Bottom water temperatures ranged from 7.9°C at Pawtuxet Cove to 12.4°C at India Point Park.

Hypoxic conditions (dissolved oxygen <2.9 mg/L) were not present at any of the sites sampled. Dissolved oxygen ranged from 5.19 mg/L at Bullock Reach to 11.9 mg/L at India Point Park. Fluorescence was low (<3 mg/m3) at all sites, and the maximum fluorescence (2.2 mg/m3) was observed at Conimicut Point.

Week of November 18 - 24, 2018

R/V Monitor's Blog

​On Wednesday, November 21st, the crew of the R/V Monitor was out on the upper Bay collecting nutrients and plankton samples, taking Secchi Disk and Par sensor water clarity measurements, conducting water column profiles using the Seabird instrument, 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.  Sara captained the boat while monitoring professionals Mike, Steve and Fern collected the samples and data.  It was a cold day, cloudy in the morning, with sun shining through by the afternoon.  There was moderate wind from the southwest, and a slight chop on the water throughout the day.  The photo below shows a spectacular view of the sky this day.

11-21-18.jpg 

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