Anne Arundel County – Office of Cultural and Environmental Resources
- Chemical, Biological, and Physical Monitoring
- Benthic Macroinvertebrate Collection, Sorting and Identification
- Aquatic Habitat Assessment
- Data Analysis, QA/QC, and Reporting
Coastal Resources, Inc. (CRI) assisted Anne Arundel County in the implementation of the Church Creek and Picture Spring Branch National Pollutant Discharge Elimination System (NPDES) Monitoring program by performing monitoring services as required by the County’s NPDES permit from February 2006 through December 2006. Specific tasks included all field-and office-related work required to conduct chemical, biological, and physical monitoring at the Church Creek and the Parole Plaza automated monitoring stations, and biological and physical monitoring at the Picture Spring Branch stream stability assessment site.
The Church Creek and Parole Plaza chemical monitoring stations consisted of ISCO automated samplers and YSI Multimeters. The Parole Plaza monitoring station also had an on-site rain gage. CRI staff visited the monitoring stations at least once per week to perform routine maintenance activities such as inspecting and testing the equipment, replacing desiccants on the ISCO automated samplers, calibrating pressure transducers and YSI Multimeters, and downloading data from YSI Multimeters. Maintenance activities performed in the office included transferring all downloaded data to CRI’s office network, reprocessing the data into Excel spreadsheets, and regenerating the desiccants.
When the weather forecast indicated a high probability of a precipitation event, CRI visited the chemical monitoring stations and prepared the equipment for sample collection (set the sampling programs, supplied the samplers with clean bottles, ensured that the laboratory analysis bottles and coolers are on-site, etc.). Potential storm events were determined by MDE criteria.
Throughout the storm event, the automated samplers collected samples at defined time intervals. CRI staff were on-site during the rising, peak, and falling limb of the hydrograph to collect the fecal coliform grab samples in laboratory-prepared containers and to store them on ice. Efforts were made to collect the fecal coliform grab samples at times that coordinate with an automated sampler rising-limb sample. After the fecal coliform samples were collected, CRI staff transported the samples to the laboratory for analysis within the six-hour holding time.
Within 24 hours after each sampling event, CRI staff visited the monitoring sites to select the automated samples that best represented the rising, peak and falling limbs of the hydrograph for the particular event sampled. This resulted in three discrete samples for each storm. The sample collection times of each sample, stream level, and the position of the sample on the hydrograph were recorded. A composite sample was created by combining each discrete sample. Composite samples were then decanted into the laboratory-prepared containers and stored on ice to await pick-up and transport service provided by laboratory personnel to the laboratory for analysis. Samples were analyzed for parameters as defined by the NPDES permit.
Eight storm events were sampled at the two monitoring stations. Duplicate samples of one storm event per monitoring station were sent to the laboratory for QA/QC purposes. Analytical results were linked to the continuous rainfall, stream stage, pH, conductivity, and temperature data, and used to calculate Event Mean Concentrations (EMCs) in accordance with procedures required by the County’s NPDES permit. All data entry followed applicable QA/QC procedures.
Aquatic Habitat Aquatic
habitat was visually evaluated utilizing the Maryland Biological Stream Survey (MBSS) Physical Habitat Index (PHI) (Paul 2002). The MBSS PHI is partly based on the Environmental Protection Agency’s Rapid Bioassessment Protocol but it incorporates other parameters also found to be indicative of habitat quality in other Maryland streams. These parameters include shading, distance to the nearest road, instream habitat, bank erosion, and instream woody debris and rootwads.
Benthic macroinvertebrate collection was conducted using the MBSS Spring index period protocols. This method emphasizes the community composition and relative abundance of organisms in the most favorable habitats. The most favorable habitat is a riffle area followed by, in order, gravel/broken peat and/or clay lumps in a run area, snags/logs that create a partial dam or are in a run area, undercut banks and associated root mats in moving water, submerged aquatic vegetation (SAV) and associated bottom substrate in moving water, and detrital/sand areas in moving water. The most favorable habitats were sampled in proportion to their dominance in the segment.
Starting at the downstream end of the segment, the various habitats are sampled for organisms using a D-net. In riffles and runs, the D-net is firmly placed in the substrate while the organisms are dislodged from any rocks and gravel by gently agitating a one square-foot patch directly upstream of the net opening. Any large rocks and cobbles present in the one square foot patch are gently placed within the net and cleaned to remove organisms. To sample undercut banks, the net is used to gently agitate one square-foot of roots and other substrate making up the bank. For logs and snags, the surface of the log is gently rubbed with the net and/or by the sampler. These procedures are repeated until a total of 20 square feet is sampled within the 75-meter segment. Benthic macroinvertebrates collected were sorted and identified to genus.
Water quality data were collected in-situ using a Hydrolab Quanta multi-probe meter with an SD-12 transmitter. Temperature, turbidity, pH, conductivity, and dissolved oxygen parameters were measured.
Physical Monitoring (Geomorphic Assessment)
Geomorphic sampling included a longitudinal profile survey, cross section surveys, and a representative pebble count. Data from these measurements were used to determine the stream type of each reach as categorized by the Rosgen Stream Classification (Rosgen 1996). Longitudinal profiles were performed throughout the entire study reaches. Cross section surveys were performed at five predetermined locations and located using GPS. Photos were taken of upstream, downstream, left bank, and right bank views at each cross section.