97R-18Intermediate12 min read

CECS — Pipeline Transportation Infrastructure

A pipeline is mostly repetitive — length and diameter set the cost per kilometre. The surprises live at the crossings: every river, road, or rail the line traverses is a mini-project, and the estimate's maturity hinges on route survey and crossing definition. Built on AACE 97R-18.

What this standard adds

Same five-class logic as Lesson 1, and a close cousin to the transmission-line variant (Lesson 7): length-driven cost, corridor-based uncertainty. The pipeline-specific signature is the crossing — and pipe sizing, which sets both material cost and the cost-per-km baseline.

Why pipelines are distinctive

  1. Diameter sets the unit cost — Pipe diameter and wall thickness drive material, welding, and trenching cost per km — a fundamental sizing parameter.
  2. Crossings are mini-projects — River, road, rail, and wetland crossings (often by horizontal directional drilling) cost far more per metre than open-cut line and concentrate risk.
  3. Soil & terrain along the route — Rock, swamp, and unstable soils change trenching method and cost; the route's ground conditions matter as much as its length.
  4. Right-of-way & permitting — Like transmission, easements and environmental approvals along the corridor can reroute the line and drive schedule.

Definition mapped to classes

Pipeline maturity climbs with pipe spec, route survey, and crossing definition (general pattern; the RP gives the authoritative matrix):

ClassPipe & route definitionTypical method
5Endpoints, rough length & diameterCost per km (parametric)
4Preferred route, pipe spec setPer-km by terrain + crossing allowance
3Surveyed route, crossings identifiedSegment + itemized crossings
2Detailed design, crossing methods setDetailed quantities
1Tender-level, ROW securedFull takeoff

Putting it to work

For a pipeline estimator, the class reflects how well both the pipe and the route — crossings especially — are defined. Use per-km rates with crossing allowances early, switch to itemized crossings once surveyed, and keep contingency for the corridor's ground and permitting surprises until the route is locked and the right-of-way secured.

Nine things to remember

  1. 97R-18 applies the five-class system to pipelines — anchored to pipe spec and route.
  2. It's the second linear-infrastructure variant — cost driven by length and diameter.
  3. Two drivers: the pipe spec (diameter, wall, grade) and the route.
  4. Diameter sets the unit cost — material, welding, trenching per km.
  5. Crossings are mini-projects — rivers, roads, rail cost far more per metre.
  6. Count and characterize every crossing — they're the biggest blind spot.
  7. A crossing allowance is not a defined crossing — Class 3 needs them itemized.
  8. Soil and terrain along the route change trenching cost as much as length.
  9. One framework, many dialects — pipelines are transmission's linear cousin.

Glossary

Crossing
Where the line traverses a river, road, rail, or wetland.
Crossing allowance
Early per-km provision before crossings are itemized.
Diameter / wall / grade
Pipe spec setting per-km material and welding cost.
Estimate class
Maturity level (5 roughest to 1 most definitive).
HDD
Horizontal directional drilling — a trenchless crossing method.
Open-cut
Trenched installation for normal terrain.
Pipeline
A line transporting oil, gas, water, or slurry.
Right-of-way (ROW)
The land corridor secured for the pipeline.

Check your understanding

1Which two fronts drive a pipeline estimate's maturity?
2Why are crossings so important to a pipeline estimate?
3A per-km "crossing allowance" is acceptable for which classes?
4What sets the per-kilometre unit cost of a pipeline?
5To reach Class 3, a pipeline estimate must: