There is light at the end of the tunnel for the Southern Delivery System (SDS) as crews are nearing completion on the most complex portion of work for a mile-long tunnel under Interstate 25, Fountain Creek, railroad tracks and frontage roads.
With the most difficult tasks of tunnel boring and pipe installation through the tunnel complete, all that remains is to connect the tunnel to the SDS with the final pieces of pipe. Watch tunneling video.
Located just south of Pikes Peak International Raceway, completion of the tunnel marks a significant milestone for SDS. The 105-inch-diameter boring machine drilled the tunnel through rock approximately 85 feet below the surface.
The tunnel depth for the machine was carefully studied to allow the machine to safely pass about 50 feet below bedrock for the creek. As the main machine worked through the rock heading east from I-25, a second machine worked under the surface heading west from Fountain Creek. The two machines connected the tunnel in November 2014. Since then, more than 162 sections of pipe were placed into the tunnel to link SDS across the challenging area.
This construction method saved $10 million, prevented traffic impacts to area roads, protected environmentally sensitive areas along Fountain Creek, and limited disturbances to nearby property owners.
Twelve tunnels were completed for SDS, with the I-25/Fountain Creek tunnel as the largest and most complex.