Sedimentation Engineering

What We Can Do:

Sedimentation engineering studies are often essential to successfully design and manage engineering works along rivers, lakes, and reservoirs that may be affected by erosional processes and sediment transport and deposition. Quantitative sedimentation engineering also helps meet environmental objectives, including conserving and improving aquatic habitat and restoring physically and biologically degraded streams.

Contacts
British Columbia:
Dave McLean
604.980.6011
N.California:
Brad Hall
916.371.7400
Alberta:
Gene Yaremko
780.436.5868
S.California:
Ed Wallace
626.440.0080
Washington:
Casey Kramer
360.584.9810
Quebec:
Marc Villeneuve
514.366.2970

NHC has long been recognized for our expertise and capabilities in sedimentation engineering. Our experts have published many technical articles and have edited and contributed to well-known technical guidance manuals and handbooks.

Our capabilities include: designing and conducting studies to measure erosion and sediment transport rates; numerically modeling sediment yield, transport, and deposition; designing traditional and novel systems to protect riverbanks and engineering facilities from erosion and scour; and hydraulic laboratories to physically model sedimentation problems and solutions.

Services:

NHC's sedimentation engineering studies are often conducted with geomorphic studies that examine erosion hazards, sediment sources, stream morphology and processes, and associated habitat problems.

Our sedimentation engineering services include:

  • Numerical Modeling of Sediment Sources
    Measuring and numerically modeling sediment yields from different landforms, soils, and land uses.
  • Numerical Modeling of Sedimentation
    Measuring and numerically modeling sediment transport modes in rivers, canals, and flood control channels, and sediment deposition in lakes, reservoirs, and estuaries.
  • Erosion Control
    Selecting methods, systems, and materials to prevent or reduce erosion at engineering facilities such as flood control levees, bridge and pipeline river crossings, and water intakes.
  • Sediment Management
    Developing methods to manage, block, or remove troublesome sediment deposits in canals, reservoirs, and other facilities.
  • Field Assessments and Construction of Physical Models
    These can be performed to identify sedimentation treatments to optimize pump station flow and valve operation.

Experience:

Examples of NHC’s sedimentation engineering projects for public agencies and private clients include:

  • Major Sediment Source Threatening Water Supply
    A major water supply aqueduct was threatened by inflows of contaminated sediment delivered by a mountain stream. We conducted geomorphic, hydrologic, and sedimentation engineering studies to identify sediment sources and quantities, and alternatives for storing or bypassing sediment.
  • Sedimentation of a Hydroelectric Power Canal
    The water transport capacity for a hydroelectric diversion canal was severely reduced by sediment deposition during high river flows. Site investigations and analysis of remedial measures identified a solution by improving the intake works and curtailing plant diversion during brief periods of very high river flows.
  • Bank Stabilization on a Large Sand River
    In densely-populated agricultural Bangladesh, we conducted geomorphic and hydraulic analyses of critical riverbank segments subject to rapid erosion during floods. Our proposed bank protection, using both traditional and new erosion-protection materials, was designed and installed along with a monitoring, maintenance, and upgrading program.
  • Sedimentation of a Major Hydroelectric Reservoir
    We estimated reservoir sediment inflows, and modeled the two-dimensional distribution of sediment throughflows using two hydrodynamic and sedimentation software programs calibrated against measured data. Our team estimated the annual sediment accumulation patterns and sediment trap efficiencies, and characterized long-term management implications.
  • Dam Effects on Downstream Channel Form
    NHC used numerical modeling and other approaches to study the impact of a new dam on downstream river bed and channels. Predicted changes included substantial bed degradation immediately downstream of the dam and replacement of the braided channel by a meandering channel with greater potential for bank erosion.


Measuring sediment discharge, Sacramento River at Colusa


Sediment diversion from water intake


Stabilized meandering river


Sediment diversion at flood control facility, Sacramento River at
Fremont Weir

Benefits & Results:

  • Our firm's practical experience and deep knowledge base helps clients understand the potential hazards for their engineering works as a result of erosion in the natural environment.
  • Our analyses and designs provide effective remedies for a wide range of problems related to erosion and sedimentation.