QUALITY ASSURANCE/QUALITY CONTROL
Maryland Department of Natural Resources followed specific procedures to ensure that the Tributary component of the Chesapeake Bay Water Quality Monitoring Program design was properly implemented and managed with sufficient accuracy, precision, and detection limits. Accuracy (closeness to the true value) of collected data was controlled and assured by proper use, calibration and maintenance of both field and laboratory equipment for the measurement of physical and chemical parameters.
The procedures used to control and assure the accuracy of field measurements involved the calibration of field instruments, verification of calibrations, and equipment maintenance. Most of the details of how data acquired with YSI sondes and Hydrolab sondes were quality assured and quality controlled are described in the process description elements in the Lineage portion of this metadata record.
Daily quality control checks which included the running of blanks and standards were used to control and assure laboratory accuracy.
Accuracy of Chesapeake Biological Laboratory, Nutrient Analytical Services Laboratory (CBL NASL) and Maryland Department of Health (MDH) results was also assessed through DNR's participation in the Chesapeake Bay Coordinated Split Sample Program (CSSP) a split sampling program in which five laboratories involved in Chesapeake Bay monitoring analyze the coordinated split samples. CSSP was established in June 1989 to establish a measure of comparability between sampling and analytical operations for water quality monitoring throughout the Chesapeake Bay and its tributaries. The Chesapeake Bay Program Data Integrity Workgroup oversees the CSSP. DNR followed the protocols in the Chesapeake Bay Coordinated Split Sample Program Implementation Guidelines (EPA 1991) and its revisions. Split samples were collected quarterly. Results were analyzed by appropriate statistical methods to determine if results differed significantly among labs. If a difference occurred, discussions began regarding techniques and potential methods changes to resolve discrepancies.
ADDITIONAL COMMENTS
January 2023: Scattered showers occurred the day before sampling stations CAC0031, MON0155, POT1471, and SEN0008. The water was reported to be very brown at station ANA0082, and barge and dredge equipment were evident downstream. At station CON0005, three-fourths of the bridge was blocked by debris. Hazy conditions were reported at station POT2386. The water level was recorded as being high and murky at stations CAS0479 and YOU0925. At WIL0013 the water was described as a murky greenish color, as the influence of Braddock Run was visible across the entire stream. There were no signs of ‘Didymo’ (Didymosphenia geminate) at station SAV0000, but algae were observed growing on the ramp at NBP0103, and on the rocks at station NBP0326. The water sample taken at NBP0326 had algae in the water and was resampled as a precaution.
February 2023: A power dredge was present upstream from the station at ANA0082. At station SEN0008 the pH and dissolved oxygen values were double-checked with a second meter. The water was described as ‘bubbly’ when viewed in a bucket at stations CON0005, ANT0203, and ANT0366, but was not observed to be so in the creek. The water level was reported to be high at station CON0005 and flowing over debris. However less debris was noted at this site than in previous months. Lots of algae were present at station NBP0103, and bright green algae was noted to be growing on the rocks at station BDK0000. At station WIL0013, the influence of Braddock Run was visible along the far edge of the creek, but the water was clear. The water at station NBP0534 was reported to be slightly murky due to a recent release. Thin and wispy clouds were recorded for stations CCR0001, GEO0009, NBP0326, NBP0461, NBP0534, NBP0689, and YOU1139. Strong gusts of wind occurred during sampling station POT2766.
March 2023: Two days of rain preceded sampling on 1-Mar. Heavy rain also occurred the Friday before sampling stations ANT0366, CON0180, and POT2386, and water at these locations was reported to be murky. The Secchi disk depth measurement at station XGG8251 was greater than the total depth.
Bridge work was noted upstream from station CAC0148. A winter storm brought approximately five inches of snow on 14-Mar, prior to sampling stations LYO0004, NBP0689, CCR0001, and YOU1139. Due to an active mine blowout at St. George’s Creek, Maryland Department of the Environment (MDE) was onsite at station GEO0009, where the water was described as dark orange in color. Due to this mine incident, the water was also murky at station NBP0461, however no signs of the mine blowout were apparent at NBP0326 during sampling. Water was reported to be very clear at station BDK0000, with bright green algae growing on the rocks at this location. A fisherman was observed upstream from station CAS0479, and a sewage smell was reported at this site. The clouds were described as thin and wispy at stations CAS0479, NBP0023, POT2766, and TOW0030. Windy conditions were reported at station CON0180. Station POT2766 was observed to have a lot of leaf litter flowing downstream.
April 2023: The meter used at stations ANT0044, BPC0035, CAC0148, MON0269, MON0528, and POT1830 post-calibrated out of range for specific conductance, but the data appeared normal. Clouds were reported to be thin and wispy at stations ANT0203, ANT0366, CON0180, POT2386, BDK0000, CCR0001, NBP0023, TOW0030, WIL0013, GEO0009, LYO0004, NBP0461, YOU1139, and POT2766. Lots of geese were observed at station ANT0203. Algae were present on the rocks at station BDK0000.
May 2023: Rain was reported earlier in the day before sampling CON0180, where one third of the bridge was blocked by debris on the lower eastern side. Rain occurred during the week before sampling at stations POT2386, YOU1139, NBP0689, and LYO0004. Heavy rain the evening before, and rain and thunderstorms the morning of sampling, was noted for stations CAS0479 and CCR0001. Water appeared tannic at station CCR0001. Hazy conditions were noted at stations LYO0004, GEO0009, NBP0461, NBP0534, NBP0689, and SAV0000. A possible release due to rain was noted for station NBP0534. ‘Didymo’ strands were observed to be present on multiple rocks at station SAV0000. Dissolved oxygen values at station NPA0165 were double checked. At station YOU0925 a fuel or oil spill was observed to be draining into the river slightly downstream from the sampling location. The Secchi disk depth measurement at station XGG8251 was greater than the total depth.
June 2023: The following stations were reported as being hazy due to Canadian wildfires: PXT0972, PXT0809, MON0528, ANT0044, BPC0035, CAC0148, MON0269, POT1830, CAC0031, MON0155, POT1471, POT1596, SEN0008, ANT0203, CON0180, POT2386, ANT0366, CON0005, CJB0005, and ET5.0. At station CON0005 debris was reported to be piled up along the right side of the bridge. There were no signs of ‘Didymo’ at station SAV0000. Rain was reported for most of the day prior to sampling stations CCR0001, LYO0004, and YOU1139. Station NBP0534 was sampled at the peak of release. Water was noted to be quite clear at station GEO0009, and dark brown at station BDK0000. At station WIL0013, where it was reported to be the first rain in weeks, the water was full of sediment.
July 2023: Field staff successfully navigated around a road closure and fixed a pump at station DER0015. Rain showers occurred the day prior to sampling stations ANT0203, ANT0366, CON0005, POT2386 and CON0180. Rain was recorded the Sunday preceding sampling at stations WIL0013, POT2386, DER0015, CAS0479, NBP0023, NBP0103, YOU0925, YOU1139, POT2766, and BDK0000. Water was reported to be murky from the Sunday rain at YOU1139, yet clear at BDK0000 despite the rain. Tannic water was observed at station CCR0001. The clouds were described as ‘thin and wispy’ at stations CCR0001, YOU1139, and LYO0004. The water level at station POT2386 was recorded as being low. At station SAV0000 fishy-smelling scat was detected, possibly from otter. The dissolved oxygen values at station GUN0125 were noted as being high.
August 2023: Hazy conditions were noted at stations ANT0366, ANT0203, CON0180, CON0005, POT1471, SEN0008, ET5.0, and MON0155. At station CON0005, three quarters of the bridge was blocked by debris, and algae was observed along the right eastern streambank, upstream of the bridge. Rain fell earlier in the day at station NBP0689, and it was noted that the ground was still wet. Rain was noted overnight prior to sampling station YOU1139, and rain overnight and continued during sampling station LYO0004. Strong thunderstorms occurred on the Monday preceding sampling stations WIL0013, CAS0479, and YOU0925. Sampling at station WIL0013 was difficult due to an ongoing pipe installation. Very cold water was noted at stations GUN0476 and GUN0258, with an additional note of high dissolved oxygen being observed at station GUN0258. At station NBP0023, the thermometer was hung in the shade behind a sign to obtain a more accurate air temperature.
September 2023: Weekend rain may have caused murky water conditions at station CAS0479. Rain was noted early in the morning prior to sampling stations YOU1139, LYO004, NBP0689, and CCR0001. Water clarity was purported to be clear at station NBP0689, but very tannic at CCR0001. Bridge construction work was observed downstream at station CON0005, it was also noted that three quarters of the stream was covered in plants, algae, and debris. Lots of green algae in the water were also reported at station GUN0125; submerged aquatic vegetation (SAV) was observed at POT2766. Low water levels were reported at stations LYO0004 and NBP0689.
October 2023: Algae was observed on the rocks at stations GEO0009 and SAV0000. At station CON0005, over half of the bridge was blocked with debris, and a build-up of algae, scum, and submerged aquatic vegetation (SAV). A slight haze on the horizon was noted at station ANT0203, while the clouds at station NBP0461 were remarked to be ‘thin and wispy’. Water clarity conditions were reported to be clear at station NBP0103, cloudy at station BDK0000, and tannic at station CCR0001.
November 2023: Clouds were noted to be thin and wispy at stations YOU1139, GEO0009, NBP0326, NBP0534, LYO0004, NBP0461, NBP0689, and SAV0000.
The water level at station POT2386 was low, but water was reported to be clear. Submerged aquatic vegetation (SAV) was observed upstream at station CON0005, and half of the bridge was blocked by debris. Station YOU0925 was reported to be very windy during sampling.
December 2023: The clouds were described as thin and wispy at stations YOU1139, NBP0461 and SAV0000. Flurries occurred during sampling at station ET5.0. At stations CON0180 and CON0005 green algae was observed in the stream, however there was no algae visible in a bucket grab sample. There was also red sediment noted on the water surface at CON0180, and sample pads at that location were green. A greenish tint to the water was also noted at station NBP0689. The bridge at station CON0005 was blocked by two-thirds by debris and a foamy build-up. The water at station YOU1139 was noted to be slightly dirty from the rain and snow over the weekend prior to sampling.