Anne Arundel County Department of Public Works (DPW)

Key Services

  • Stream Assessment
  • Biological Monitoring
  • Data Management and Analysis
  • Report Preparation
  • GIS Analysis

Project Details

OLYMPUS DIGITAL CAMERACoastal Resources Inc. (CRI) is a consultant on this multi-year open-end contract with the Anne Arundel County Department of Public Works.  Under this contract, the DPW requested a biological assessment of twenty-four (24) targeted stream sites within the Herring Bay watershed in 2013.  This assessment was in response to the Anne Arundel County National Pollutant Discharge Elimination System (NPDES) Municipal Separate Storm Sewer System (MS-4) permit, which requires an assessment of water quality within the County’s watersheds.  The County will incorporate data from this study into their Watershed Management Tool (WMT) and it will be used to assist in the completion of a comprehensive watershed assessment, under separate scope.

Biological monitoring includes benthic macroinvertebrates, qualitative aquatic habitat, and in-situ water chemistry, which was used to determine baseline conditions of the streams in the watershed.  Monitoring was conducted according to DPW standard operating procedures, which are based on Maryland Biological Stream Survey (MBSS) protocols and U.S. EPA Rapid Bioassessment (RBP) Protocols.  Prior to biological monitoring fieldwork, CRI identified private parcels that may be impacted by the stream sampling.  A list of private parcels potentially impacted by the field work was sent to the County to facilitate property owner notification.

Benthic macroinvertebrate samples were processed and subsampled using guidance from the County SOP and the MBSS Laboratory Methods for Benthic Macroinvertebrate Processing and Taxonomy.  Each 120-organism subsample was sent to a lab for identification to the genus level for most taxa.  Ten percent of identified samples were randomly selected for identification by CRI (a certified laboratory) as a quality control measure, in order to calculate the Percent Taxonomic Difference (PTD).

Benthic macroinvertebrate data were analyzed by calculating the Benthic Index of Biotic Integrity (BIBI) for Coastal Plain streams, following guidance established in the MBSS’s New Biological Indicators to Better Assess the Condition of Maryland Streams.  RBP physical habitat data from each site were used to calculate a total score for each site and assigned a narrative rating according to the percent comparability to reference.  MBSS physical habitat data from each site was used to calculate a Physical Habitat Index (PHI) for each site.  A correlation analyses was be performed using biological and physical habitat data to determine which variables show strong response.  CRI also performed an impervious surface/land use analysis for each sampling location.  Data from these analyses was used to determine the overall baseline conditions of the streams in the Herring Bay Watershed.

CRI followed rigorous QA/QC procedures for all aspects of the project including staff training, certification, calibrations, data entry checks, field data collection checks and other measures as issues were identified.  The effort entailed close and constant coordination with DPW through all project components, including field work planning, data submittals, and collaboration on reports that integrated County background information with monitoring data.