Design of Pipeline Shore Crossings using Trenchless Methods

Increasingly, trenchless methods are being incorporated into shore crossing designs as an alternative to traditional open cut and cover methods. These can be used to help minimise impact on the coastal environment. Two trenchless shore crossing methods being used with an increased frequency are horizontal directional drilling (HDD) and microtunnelling.

Design challenges for a trenchless pipeline shore crossing extend beyond considering pipeline mechanical, stability and cathodic protection design. Engineers must also tackle the challenges associated with the trenchless methods of HDD or microtunnelling at a coastline and ensure they are suitably integrated with the pipeline design. Every pipeline shore crossing is different and no method is universally suitable. Costs and risks involved will change with every site, and every project.

This paper provides an overview of the pipeline shore crossing method selection and design processes. It highlights the issues, benefits and key parameters associated with adopting trenchless designs for pipeline shore crossings.