Major CA Bursting Project Proves Very Cost-Effective

By Jeff Griffin, Senior Editor | October 2013, Vol. 68 No. 10
Assisting pipe insertion to dive under and clear a water service while pipe bursting eight-inch vitrified clay pipe

To eliminate receiving pit excavations at difficult areas such as intersections, trailer parks, near telephone poles, and similar conditions, a reversible Hercules Grundocrack pneumatic hammer with front expander and the 10-ton winch was used for installing 10- and 12-inch pipe for single upsize runs.

A rear expander Hercules 8.5-inch diameter pneumatic hammer and the 10-ton Grundowinch was used to install 10-inch pipe on longer runs to provide more power and better maintain grade.

To provide more power on longer run lengths for single and double upsizes of 12-inch pipe, a rear expander Gigant 10.5-inch diameter Grundocrack pneumatic hammer was used and depending upon conditions, either the 10- or 20-ton winch would be used.

Insertion pit with Koloss 14-inch rear expander pneumatic hammer pipe bursting 15-inch VCP and pulling in 20-inch HDPE.

For maximum power on long runs of 16- and 20-inch pipe for making single, double and triple upsizes, the rear expander 14-inch Koloss pneumatic hammer was employed.

Morrow said work went smoothly throughout the project.

“We didn’t make the task too complicated,” he said. “We had one crew putting pipe in the ground every day. Most of the time a dozen crew members were working at bursting, pipe fusion and digging. Mocon personnel also were responsible for pipe fusion. The only times two crews were working was when Vasilj was doing open-cut the same day.”

The 33,000-plus feet of bursting was completed in approximately nine months.

The cost of the sewer capital improvement program initially was estimated to be $12 million. It was completed on schedule with the final cost estimated to be $4.4 million.

Costs
In the second and final round of bidding, cost differences between pipe bursting and open-cut construction were dramatic, ranging from $71 to $200 per foot for pipe bursting and $95 to $383 per foot for open-cut, based on a summary of all bids.

“Everything went very smoothly,” Morrow concluded. “The project design was good and anticipated potential problems so there were no unexpected construction issues. We installed more the 30,000 feet of pipe with just a hand full of small problems.”

Morrow said a significant aspect of the project was the continuity of replacing the whole system’s arteries – from the smaller pipes thought the larger diameter pipes – without skipping any reaches in between. It also is one of the larger pipe bursting projects to be undertaken in Southern California, he added.