NARROWS INLET HYDROELECTRIC – UPPER RAMONA PORTAL

Upper Ramona Portal scope included:

Compound benching rock drilling and blasting, and hauling, scaling, stabilization, mesh, shotcrete, coco matting, diversions, drain holes and anchors. Total rock excavation 90,000 m³.

DENT’s experience in rock excavation and stabilization affords us a significant advantage for any project. We work closely with a qualified rock engineer to ensure long term stability and worker safety and have safely completed numerous similar projects. 

DENT was required to construct a roadway to access the Upper Ramona Portal location. 

The Red Road connects the Upper Ramona Powerhouse to the Portal Laydown where the Lake Tap portion of the HEP meets the penstock. Red Road was designed and built to allow all construction traffic unassisted access to the portal. This included low beds with heavy drilling equipment, concrete trucks, rock trucks, cranes and light duty vehicles. Our design parameters were to construct the road with a maximum grade of 26%, a minimum turning radius of 17m at each of the 6 switch backs, truck pull outs at no greater than 100m increments for safety, and a robust drainage system to handle the heavy falls rains, winter snowfall and subsequent melt. A balance of full bench cut and side casting with engineered rock stack wall to support the outer edge of the road was used to build the Red Road. Operators and engineers worked together to ensure long term stability of the road and  quality construction.

Road Length: 850m

Start Elevation: 580m

End Elevation: 735m

Max Grade: 26%

Number of Switchbacks: 6

Material Removed: 31,100m3

Material Placed: 24,200m3