Another milestone was achieved at the Chimney Hollow Reservoir site on Nov. 8 when grouting was finished along the saddle dam foundation. This allowed crews to turn their attention to finalize foundation preparation before going vertical with the clay core, rockfill layers and other components of what will be the 40-foot-tall and 1,250-foot-long saddle dam at the southern end of the reservoir’s footprint. 

Grouting consists of injecting a cementation slurry into a foundation to fill cracks and voids below the surface, which plays a critical role in helping prevent seepage below a dam. Crews began grouting at the Chimney Hollow saddle dam in mid-August, following completion of the grout cap (the concrete foundation of the saddle dam). Throughout the next 12 weeks crews injected material into the double-row curtain along the 8-foot-wide grout cap, reaching depths of 70 feet below the surface.  

As part of prepping the saddle dam for its upward construction, crews also recently completed a successful test fill at the site, to ensure the dam-building materials compact and form to one another and the foundation as designed, as well as to test the equipment and methods that will be used in the construction.