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 2022: A winter storm brought snow on 3-Jan, causing possible impacts from snow melt and road salt to samples collected 5-Jan and 6-Jan. Heavy snow from Winter Storm Izzy occurred on 16-Jan, a few days prior to sampling at stations ANT0203, ANT0366, and POT2386. A few inches of snow fell the night before sampling at station CCR0001. The edges of the river were frozen at stations CAS0479, CCR0001, POT2766, WIL0013, and YOU0925, with the water appearing slushy at stations CAS0479 and YOU0925. Two-thirds of the river were frozen, and ice was melting off the bridge at station CON0005. At station LYO0004, the creek was frozen over downstream of the bridge. The water appeared murky at stations NBP0461, NBP0534, and NBP0689, with snow on the ground reported at station NBP0461 and unusually high conductivity noted at station NBP0689. Floating ice was observed in the river at station POT2386. It snowed overnight, and snow fell from the bridge and into the sample collected at station YOU1139. The rocks at station BDK0000 were covered in iron precipitate (yellow boy). There were no signs of didymo at station SAV0000. The secchi disk depth measurement at station XGG8251 was greater than the total depth.
February 2022: Rain, snowmelt, and ice melt were noted in the days prior to sample collection on 22-Jan and 23-Jan. Windy conditions were noted during sampling at station NBP0326. Road salt may have impacted samples collected at stations ANA0082 and CJB0005. Geese were in the area during sampling at station ANT0203. Ice covered 90% of the stream downstream of station BPC0035. At station CAC0148, ice completely covered the stream in the upstream direction and was observed on the streambanks in the downstream direction. Ninety percent ice coverage was noted at station MON0528 (upstream and downstream). The streambanks were frozen at station MON0269. Fog was present during sampling at station PXT0972. At station POT2386, the water appeared slightly murky. Debris blocked a small area in the middle of the bridge at station CON0005. The secchi disk depth measurement at station XGG8251 was greater than the total depth.
March 2022: Early morning rain occurred on 17-Mar, before sample collection at CORE stations. Algae was observed growing on the rocks at station GEO0009, and the water was very clear. At station CAS0479, a fisherman was present upstream during sampling. The water had a greenish tint at station NBP0534 and was slightly murky at station POT2386. Large numbers of box elder beetles were present at station POT2766. Station SAV0000 had no signs of didymo. Thin clouds were reported at station TOW0030.
April 2022: Lots of geese were in the area near station ANT0203 during sampling, and a fisherman was near the sampling area at station CAS0479. At station ANT0366, USGS personnel were on-site during sampling. It rained overnight before sampling at stations CAS0479 and CCR0001, and it rained the morning before sampling at stations CAS0479, CCR0001, NBP0103, and WIL0013. At station CON0005, debris blocked the creek at the center of the bridge. Thin clouds were reported at stations GEO0009, LYO0004, NBP0326, NBP0461, NBP0534, SAV0000, and YOU1139. Algae were present on the rocks at station GEO0009, and the water at station TOW0030 was tinted green. High water levels were observed at stations POT2386 and YOU1139, with the water at POT2386 appearing murky.
May 2022: Rain storms, some with thunder and heavy downpours, occurred the evening of 3-May and the morning of 4-May, impacting samples collected on 4-May and 5-May. Additional storm-related observations were noted at stations SEN0008 (muddy water), YOU0925 (high water level), and CCR0001 (orange/tannic water). Heavy rain continued over the weekend prior to sampling activities on 11-May. The weekend rain event caused high water levels and murky water at stations ANT0203 and CON0180. At station CON0005, three-fourths of the bridge was blocked by debris from the weekend storm, and at station POT2386 there was evidence that water levels had overflowed the riverbank.
June 2022: Scattered showers occurred the night before sampling at stations CB1.0, DER0015, GUN0258, and GUN0476. Overnight thunderstorms were noted at stations LYO0004 and YOU1139. At station CCR0001, the water appeared tannic and was slow moving. Rain earlier in the day left the parking lot wet at station CON0005, and a large amount of debris blocked 3/4ths of the bridge. At station CON0180, observations of wet ground and brown water were noted. It was windy during sampling at station NBP0326.
July 2022: The water appeared slightly murky at station ANT0366 and tannic at station CCR0001. Thin clouds were reported at station BDK0000. At station CON0005, debris blocked two-thirds of the bridge on the upstream side; downstream, flow was open along the eastern shoreline. Lots of algae were observed at station GEO0009. Heavy rain fell overnight before stations LYO0004 and YOU1139 were sampled. At station WIL0013, the influence of Braddock Run was visible across the entire stream. The water level was low during sampling at station NBP0023, and the water appeared clear.
August 2022: Algae (possible filamentous) were observed at station BDK0000, and the water was clear. The water at station CCR0001 was very tannic. At station CON0005, debris blocked two-thirds of the bridge, with flow along the left eastern streambank open. At the time of sampling, a foul smell was noted in the air at station GEO0009, and algae were present in the water. It rained the night before sampling at stations GUN0125, GWN0115, JON0184, NPA0165, PAT0176, and PAT0285. Lots of SAV were observed at station GUN0125.
September 2022: Thin clouds were reported at station BDK0000 at the time of sampling. The water was described as “bubbly” at stations BDK0000, CCR0001, and NBP0023, and as “frothy” at stations CAS0479 and YOU0925. The water at station CAS0479 also appeared brown. It rained the night prior to sampling at stations CCR001, GUN0258, GUN0476, and POT2386. Morning rain was noted at stations GUN0125, GWN0115, JON0184, and NPA0165. Rain fell during the weekend before and again on the day of sampling at stations CAS0479, CCR0001, TOW0030, WIL0013, and YOU0925. At station CAC0031, a downpour occurred prior to and during sampling. Station YOU1139 was sampled after several days of rain and the water was dirty. At station WIL0013, the influence of Braddock Run was visible across the creek.
October 2022: The remnants of Hurricane Ian brought rain to the region in the days prior to sampling at stations ANT0203, ANT0366, CON0005, CON0180, and POT2386. At station BDK0000, the water appeared grayish and the filter pads looked orange. At station WIL0013, the influence of Braddock Run was observed as an input of greenish/gray water across the creek. Morning showers were reported at stations ANT0044 and POT1830. Algae were observed on the rocks at station GEO0009. At stations ANT0203 and ANT0366, the water appeared clear. The bridge at CON0005 was almost entirely blocked by debris; only the far right side of the bridge had flowing water. The water was murky at station POT2386. At station XGG8251, the Secchi disk depth measurement was greater than the total depth at the station.
November 2022: Rain fell the night before sampling at stations DER0015, GUN0476, and CB1.0, with foggy conditions noted at stations DER0015 and CB1.0. At station GEO0009, the water had a grayish tint and algae were observed on the rocks. Snow flurries were reported at stations NBP0103, NBP0326, POT2766, and TOW0030. Station NBP0689 was sampled during windy conditions, and slush was observed floating downriver at station YOU1139. At station WIL0013, the influence of Braddock Run was visible along the right shoreline. Hurricane Nicole passed through the region on 11-Nov, a few days before stations ANT0203, ANT0366, CON0005, CON0180, and POT2386 were sampled. The water appeared clear at station ANT0203 and murky at station CON0180. At station CON0005, 4/5ths of the bridge was blocked by debris.
December 2022: The meter used at stations PXT0809, PXT0972, DER0015, GUN0258, GUN0476, CB1.0, ANA0082, RCM0111, POT1184, and CJB0005 post-calibrated out of range for pH, but the data appeared normal. It rained during the two days prior to sampling at station ET5.0. Fog was noted at station PXT0972, and flurries were reported at station NBP0103. The clouds were described as thin and wispy at stations GEO0009, NBP0326, and NBP0461. At station ANT0203, partly sunny skies were noted. Algae were observed during sampling at station NBP0326. At station WIL0013, the influence of Braddock Run appeared as light brown water along the right shoreline. Light rain fell earlier in the day at station ANT0366. At station CON0005, 4/5ths of the bridge was blocked by debris.