Boulder Creek Stabilization Project
cbec eco engineering (cbec) developed design plans for stream bed repairs associated with Boulder Creek, downstream of the Lawson Portal, along the toe of the Boulder Creek Landslide.
Channel incision and bank erosion were exacerbating slope stability by undermining the toe of the landslide, impacting the Lawson Mine Portal and acid mine drainage infrastructure integrity. cbec staff assessed site hydrology and developed a 1D HEC-RAS model to simulate existing flows and the resulting bed shear stresses. The RAS model was used to evaluate the design of a step-pool structure to dissipate stream energy and bed shear, thereby stabilizing the channel and reducing erosion at the base of the landslide. The step-pool structure was constructed at the end of 2013. cbec played an integral role in the success of the constructed project by providing full-time construction surveying and oversight. cbec has monitored the design since its installation to assess the success of the design.
Specific technical tasks undertaken by cbec included:
- Hydrologic study/hydraulic modeling of existing and design conditions
- Site topographic and channel surveys
- Step-pool design
- Riprap sizing
- Development of construction documents
- Construction observation and support services
- Post-project monitoring