WV Regional Water Intake System
The original design of the Summersville, WV Regional Water intake called for a 12’ concrete-lined intake shaft with two 24” micro-tunnels at different lake elevations. NAD value engineered the design resulting in a new piping layout consisting of the two lake taps running through one single 38” conduit, “single tunnel—dual source.”
The shaft was drilled through extremely tough rock that reached compressive strengths as high as 38,000 psi with abrasiveness capable of wearing cutters out in a matter of feet. Shaft drilling commenced May 12, 2003 and was completed on July 30, 2003 after two full cutter changes to a depth of 130’. (See Photo of Shaft Drilling)
A 60” horseshoe tunnel was drilled and blasted to tap the lake, approximately 540’ from the intake shaft. Within the tunnel, 39” PermalokT pipe was installed and grouted in place. Approximately 50’ from the lake shore line, a T-section was installed inside a secondary access shaft to access the upper summer pool tap. 540’ of 24” HDPE was then fused together and pulled all the way through the PermalokT pipe from the lake via a crane and pulley system at the main intake shaft.
This arrangement allowed the summer tap to flow into the PermalokT casing while remaining isolated from the winter tap, HDPE line.
Isolation of the two taps at the intake shaft was achieved through the design of manifold and mandrel that was specially fabricated with stainless steel.
On August 12, 2004, NAD witnessed the City of Summersville draw water from the lake through both lake taps and successfully pump water up to the new Water Treatment plant.
Below you can see the Autocad drawing done for this project as well.