The county has standardized PVC for HDD applications. Of the total seven HDD bores, five utilized Certa-Lok® PVC installed at a depth of 15 ft - 18 ft, while the other two HDDs utilized HDPE. The project was originally designed with 600 LF to 1000 LF Certa-Lok drills. However, during construction the contractor requested to combine two of these drills in order to increase efficiency and reduce traffic disruption. The planned 1540 LF HDD was modified on site by shifting the entry and exit points leading to the formation of a 1483.5 LF 16-in. diameter Certa-Lok PVC HDD, one of the longest segmental PVC drilled in this diameter in Florida. The owner/engineer agreed to the request, which included confirmation of pullback force calculations for the longer drill along with the indication that ballasting would be required.
The published maximum safe pullback force for 16-in. DR-18 Certa-Lok is 72,000 lb, which includes a base safety factor (SF) of 2.0. The longest drill had a calculated pullback force for the unballasted scenario of 69,000 lb. With ballasting, the calculated pullback force was reduced to 39,000 lb, which was well below the published maximum. The contractor utilized a Vermeer D60x90 drill rig, with a pullback capacity of 60,000 lb. The maximum recorded pullback force required during installation was 55,000 lb. The pullback was ballasted and was completed within nine hours.
Some of the project’s Certa-Lok pullbacks were installed cartridge style with each pipe joint added to the pipe string sequentially during pullback. Where space allowed, multiple segments of Certa-Lok were staged in a longer pipe string, with intermediate joint assemblies occurring during pullback. Pullback for the longest drill included staging of four roughly 400 LF pre-assembled pipe segments, with intermediate joint assembly during pullback. Ballasting was accomplished by pre-installing quick connect hoses within the pre-assembled pipe segments, with connections made prior to intermediate joint assemblies. Water from a metered fire hydrant was delivered into the end of the pulled segment, with the end of the hose located downhole of the overbend near the pipe entry. When pullback progress slowed excess water escaped the end of the pulled segment, allowing for confirmation that all downhole piping was ballasted.
In the Gibsonton S2S Phase 1B project, the strategic use of HDD with segmental PVC along congested and high-traffic corridors minimized disruptions to the community while ensuring the safe and efficient installation of critical force mains.
“This project demonstrates how trenchless construction can have significant benefits to the community,” said Tyler Lirio, project manager of Ric-Man Construction Florida, Inc. “By horizontal directional drilling with 16-inch C900 Certa-Lok PVC, we were able to successfully install a 1,483.5-linear-foot segment—one of the longest of its kind in Florida. Horizontal directional drilling with Certa-Lok pipe allowed us to minimize disruptions along heavily traveled roads, keep traffic moving, and safely complete a challenging installation. It’s a great example of how innovative construction methods can minimize impact to the community while still delivering the necessary upgrades to our infrastructure.”
The project successfully executed a 1483.5 LF, 16-in. diameter Certa-Lok PVC HDD segment. This was accomplished through proper planning and design along with coordination of ballasting and joint assembly logistics. All piping was installed comfortably below the manufacturer’s recommended maximum safe pull force. As of August 2025, all HDD installations are complete, with open-cut piping and system tie-ins expected to be complete by the end of 2025. Upcoming projects in neighboring Florida counties are already underway with planning in progress to initiate HDD pulls of Certa-Lok as long as 2000 LF.
