In the Trenchless construction bidding, Many time, cost and execution problems do not arise from failures in the work itself, but much earlier: in the way the layout, geotechnics, scope, technical criteria and starting assumptions are defined. A specification may appear correct from an administrative point of view and yet generate unreliable comparisons between bids, awards with hidden risks or solutions that are difficult to implement once the work has begun.
The most frequent errors are often repeated: insufficient documentation, award criteria too focused on price, poor definition of scope, incomplete geotechnical engineering, lack of consistency between layout and construction method, and little attention to actual constructability. In projects of pipe ramming and microtunneling, these errors can then be passed on to cost overruns, method changes, underperformance and contractual tensions during execution.
Most common bidding errors in trenchless projects
Bidding with insufficient or unrepresentative geotechnics
One of the most common mistakes is to put out to tender a crossing with scarce geotechnical information, poorly distributed or poorly connected to the actual layout. When the terrain is not well characterized, bids are built on different assumptions and are no longer comparable under equal conditions. In addition, there is an increased risk that the awarded solution is not the most suitable for the actual subsurface conditions.
Defining the layout without validating its constructability
Another common mistake is to tender a solution that fits the plan, but which has not been checked from the execution point of view. Coverage, radii, depth, attack and reception points, construction site implementation or coexistence with affected services can turn an apparently viable route into a highly complex alternative. When this review is not done before bidding, the contractor ends up inheriting uncertainties that should have been resolved in the engineering phase.
Failure to differentiate between the technically feasible method and the truly optimal method
In trenchless construction, it is not enough to know if a method can be executed. It is also necessary to assess whether it is the most robust in terms of risk, control, time and overall cost. A poorly refined specification may lead to a simplified comparison of solutions of horizontal directional drilling, microtunneling or Direct Pipe without clearly defining the criteria for compatibility between terrain, layout, pipeline and environment.
Mistakes that distort the comparison between offers
Value almost solely on price
When the price weighs too much and the technical criteria are not well structured, the bidding process stops rewarding the best solution and begins to favor the most aggressive or least risk-explicit proposal. This can lead to apparently competitive awards, but weak from the point of view of actual execution.
Failure to properly close the scope of each offer
Many differences between bids are not in the method, but in what each bidder understands to be included. If the specifications do not clarify which items are part of the scope - detailed engineering, ancillary civil works, sludge management, topography, testing, final documentation, site treatment or technical support - the comparison between proposals becomes unreliable from the outset.
Failure to require sufficient technical justification
Another common mistake is to allow bids that are technically very brief, without a clear explanation of the excavation system, expected yields, thrusts, risk treatment or sequence of work. Without this level of definition, the contracting authority can compare amounts, but not solutions.
Civil works and implementation errors that are often late in arriving
Underestimate the attack, reception and auxiliary work points.
In many tenders, the focus is on the crossing and not on the civil works that make it possible. However, the feasibility of the method depends to a large extent on the execution of shafts, platforms, containment, access, staging areas and implementation logistics. When these elements are not well defined, the work may force to revise the planned method or to assume costs not contemplated. This is especially relevant when vertical wells or complex auxiliary configurations.
Failure to properly assess the affected environment
A very common mistake is to treat a crossing in an open area in the same way as a crossing under a railroad, main road, urban area or corridor with many services affected. Safety restrictions, permits, schedules, occupation and control significantly change the execution strategy. In infrastructure crossings, This point should be clearly integrated into the bidding documents.
How can these errors be avoided before issuing the solicitation document?
With more technical definition and fewer implicit assumptions
The best way to avoid bidding errors is to arrive at the bidding documents with a more solid technical basis: validated ground plan and profile, sufficient geotechnical data, coherent hydrogeological information, revised affected services, identified environmental conditions and a first real constructability check.
With award criteria that compare solutions, not just amounts.
The evaluation should also be structured to assess the consistency between method, terrain, route, time, means and scope. This makes it easier to distinguish between a cheap bid and a technically sound bid.
With a better prepared RFQ or bidding documentation
When the initial documentation is well prepared, the bidding process becomes more transparent, bids are more comparable and the risk of subsequent changes is reduced. In trenchless works, a good bidding process not only seeks to award the contract, but also to do so with a solution that can be executed with safety, precision and control.
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