Stilling basin design and operation for water quality : field testing, final report.

Details

• Creators:
  McLaughlin, Richard A.
• Corporate Creators:
  North Carolina State University. Soil Science Dept.
• Subject/TRT Terms:
  • Stilling basins
  • Turbidity
  • Sedimentation
  • Stilling basins
  • Polyacrylamide
  • Sedimentation and deposition--North Carolina
  • Water--Pollution--North Carolina--Prevention
  • Roads--Design and construction--Environmental aspects--North Carolina
• Publication/ Report Number:
  FHWA/NC/2007-02
• Resource Type:
  Tech Report
• Geographical Coverage:
  North Carolina
• Edition:
  Final report; July 2007-June 2008.
• Corporate Publisher:
  North Carolina. Department of Transportation. Research and Analysis Group
• Abstract:
  Many construction projects involve the need to pump turbid water from borrow pits or other excavations into stilling ; basins or sediment bags prior to discharge. The design and operation of these basins needs to be optimized to ; provide the best water treatment prior to discharge. This project was designed to provide an evaluation of stilling ; basin designs and polyacrylamide (PAM) injection to minimize turbidity in discharged water. A Piedmont subsoil ; was mixed with water in a large holding pond which served as a source of the turbid water which was pumped into ; the stilling basin. Initial turbidities were in the range of 250-400 nephelometric turbidity units (NTU) in the source ; basin. Physical changes to the open basin, both with porous baffles and distribution along the bottom, significantly ; reduced turbidity or total suspended solids in the stilling basin, but the highest reduction was only 25%. Chemical ; treatment with PAM reduced turbidity and TSS by up to 88% and 84%, respectively, with little effect from the ; baffles or bottom spreader. Both types of PAM dosing systems worked well. There was some evidence that flocs ; formed after PAM treatment were intercepted by the dam slope. The porous baffle with 10% open pore space was ; significantly more effective than the baffle with 45% open pore space, but only when no PAM was added. The ; PAM treatments were highly effective and should be relatively simple and economical to use to reduce turbidity in ; pumped water.
  More +
• Format:
  PDF
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/17188/dot_17188_DS1.pdf
• File Type:
  [PDF - 483.91 KB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:8e81602710f0e07312c8724c4a357a1c9dd0562ba4c9ef9d263d5a57ada3db21