Estimate of cliff recession rates for the Baraga Cliffs.

Details

• Creators:
  Vitton, Stanley ; Williams, Alexander
• Corporate Creators:
  Michigan Technological University. Department of Civil and Environmental Engineering
• Corporate Contributors:
  Michigan Tech Transportation Institute
• Subject/TRT Terms:
  Cliffs Cliffs--Erosion--Michigan Erosion Soil Erosion--Michigan Soil Erosion Prediction--Michigan Soils
• Publication/ Report Number:
  RC-1526
• Resource Type:
  Tech Report
• Geographical Coverage:
  Michigan
• Edition:
  Final report.
• Corporate Publisher:
  Michigan. Dept. of Transportation. Construction and Technology Division. Testing and Research Section
• Abstract:
  A section of highway US-41 seven miles north of Baraga, MI runs along a 100 foot high cliff overlooking Keweenaw
  
  Bay. Since construction of the highway, cliff recession has advanced to a point where it is allowing the undercutting of
  
  the guardrail system of the highway and threatening the highway’s overall stability. A research program was
  
  conducted to determine the cliff’s recession rate and if the highway should be relocated. The analysis included
  
  investigating variations in shore platform widths, environmental factors, and rock characteristics. Laboratory testing of
  
  the cliff rock included point load testing and uniaxial compressive testing, while the rock quality designation (RQD)
  
  and rock mass rating (RMR) were determined from the rock core drilling. Factors affecting the rate of cliff recession
  
  are: (1) rock weathering and water migration from surface water as well as from water flowing above low permeability
  
  layers within the cliff face rock; (2) removal of weathered cliff talus material at the base of the cliff by long shore
  
  currents and wave action; and (3) the long term development of a stable talus slope at the base of the cliff. It was
  
  found that the average cliff recession rate was between 0.15 and 1.5 inches per year but that various sections of the cliff
  
  were regressing at a faster rate due to more localized factors. Survey data of the stable slopes to the south of the cliff
  
  indicate that stable slopes develop at between 30° and 33° slopes. It is likely that the Baraga Cliffs will naturally
  
  evolve to this slope angle similar to the slopes to the south of the cliffs. It is recommended that the highway be
  
  relocated to a position beyond where a stable slope will develop. This recommendation, however, is premised on a
  
  stable talus slope forming and successful vegetation developing on the slope. This also assumes that the lake levels
  
  remain at their current level or near the long term lake average.
  
  
• Format:
  PDF
• Funding:
  2006-0414
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:b862994ac66d169a391c0da4f9a1220c1115b0000034221e9c7238ebb837d5d2
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/18192/dot_18192_DS1.pdf
• File Type:
  [PDF - 5.47 MB ]