Reference

Steve Stewart, 410-887-4488

Baltimore County EPS

Project Highlights

  • Wetland Delineation
  • Functional Assessment
  • Water Quality Sampling – Chemical & Biological
  • Geomorphic Assessment
  • Natural Resources Mitigation
  • Environmental Stewardship Opportunities
  • Natural Environmental Technical Report
  • Environmental Impact Statement

Project Details

pic_proj_gwynns

Coastal Resources, Inc. (CRI) was tasked with performing a watershed study and developing a management plan for the Gwynns Falls Watershed located in western Baltimore County  and Baltimore City.

The watershed study area included the following subwatersheds: Red Run, Horsehead Branch, Scotts Level Run, Powder Mill Run, Dead Run, Gwynns Run, Maidens Choice and the Gwynns Falls Mainstem. For each subwatershed, CRI performed a watershed characterization, a stream stability assessment, a cruised reach stream assessment, a forest assessment, and a stormwater management retrofit assessment. CRI developed and ranked restoration goals and management strategies for each subwatershed.

CRI also developed a GIS database to store information gathered throughout the study, such as locations of water quality problems and restoration management projects.

For the cruised reach stream assessments, the streams were divided into individual reaches averaging 750 linear feet. CRI used regional curve data developed for the region to determine ranges of hydraulic geometry relationships based on the bankfull discharge and to field-calibrate observations. Cruising consisted of a team of two surveyors walking the entire length of each stream and performing rapid field assessments of individual reaches. Measurements using a stretched tape and surveyors rod were performed to estimate bankfull depth and width.

Channel morphology features were estimated by observation and map interpretation included:

  • Entrenchment ratio range
  • Sinuosity range
  • Channel slope range
  • Width/depth ratio range
  • Meander pattern
  • Depositional features
  • Channel substrate
  • Channel stability: aggrading, degrading, lateral stability
  • Stream Classification Type (Rosgen)
  • Geologic controls
  • Bank Failure Assessment
  • Channel Evolution Stage
  • Bank instabilities
  • Altered channels
  • Debris blockages
  • Culvert (type, shape, estimated span, EOP pool)
  • Utilities: exposed/leaking sewer lines, manholes, etc.
  • Fish blockages
  • Riparian width for each side of the channel
  • Riparian cover/composition/density
  • Canopy cover (percent over channel)

The field team also identified stream rehabilitation or remediation projects. Project descriptions included location, purpose of improvements, linear extent, types of improvements, potential for success, and potential benefits.