Linear Projects

Disruption to pipelines

Are pipelines truly linear projects or simply a series of inter-connected special sections?

With a few exceptions, onshore pipelines comprise linear sections of varying lengths, interrupted by obstacles in the form of roads, railways, rivers and streams, wetlands, other pipelines, steep slopes, power lines and the like.

It is the number of such crossings and the method(s) required for crossing them that will determine the extent that a project can be considered as a linear project.

Impact of crossings / special sections

Crossings and special sections disrupt mainline operations. They force mainline works to stop and either a move forward along the right of way or a move around to avoid an obstacle. The nature of the obstacle will determine which applies.

For major rivers, motorways, most railways, and some wetlands, operations cannot cross the obstruction directly. Crews will have to track back along the right of way and be moved by low-loader to an access point beyond the obstruction and then track back up the right of way close to the opposite side of the obstacle to re-commence work.

For minor obstructions, streams, smaller roads etc. crew may be able to track forward without the need for low-loader moves. But even in this case time for mainline crew operations will be lost.

Crossing will generally be installed by specialist crews either using trenchless technologies or by open-cut with tie-ins welded below ground. In all cases there is likely to be additional excavation and backfill for additional depth of cover at crossings and for bell-holes for tie-ins.

Impact of changes in number of Crossings

An addition of one or two minor crossings may not significantly disrupt mainline operations, however when significant numbers of additional crossings are identified mainline operation will be affected.

The impact of the additional crossings includes:

• the work, cost and delay caused by installing the crossings as special sections,

• the increase of crew moves forward or around the obstructions, and

• losses of productivity due the reduction in length of pipeline that can be installed by mainline techniques coupled with the increase in stop/start working.

Evaluation of changes in number of crossings

The cost and time directly incurred in installing the crossings should be a matter of record, and depending on the terms of the contract may be reimbursed as unit price items, lumps sum or at time and material rates.

However a significant part of the cost and time impact of the additional crossings may be due to the losses of productivity to mainline operations.

Loss of productivity is best calculated by using the "measured mile" approach, proving production in uninterrupted sections of the same pipeline and comparing costs in sections that have been disrupted.

If all sections have been impacted, and obtaining a measured mile on the pipeline becomes difficult, it may be necessary to review data from similar projects or a published set of norms to find benchmarks that may apply.

Supporting claims and entitlements

Lack of a measured mile should not affect entitlement to reimbursement for additional costs and delays, but may make it more difficult to prove the actual impact.

In making claims, after having ensured that due notice is given, the three most important elements of a claim are Records, Records and Records.

If you need assistance with claims contact PFCL at phil@pfryer.com