In a project of microtunneling, The main contractual and schedule risks do not usually come only from the excavation, but also from how it is tendered and how much is defined before starting. When the project goes out to tender with relevant uncertainties about terrain, affected services, permits, implementation, acceptance criteria or division of responsibilities, the likelihood of modifications, claims, deadline extensions and cost deviations increases. The architecture of the Eurohinca site already reinforces this logic of prior preparation, with contents on technical assistance and engineering, quality control and field contingencies.
Therefore, the best way to reduce contractual risk is not to wait for the execution of the contract, but to close from the bidding process what information is considered as the basis of the contract, what assumptions each party assumes and how deviations will be dealt with if conditions different from those foreseen appear.
The most common risk: geotechnical uncertainty and actual ground conditions.
One of the most frequent sources of risk in microtunnelling is that the geotechnical information does not represent well the real terrain of the crossing. If the soundings are insufficient, poorly distributed or do not capture changes in strata, boulders, fills, rock, water or abrupt transitions, the contractor may find himself on site with conditions different from those tendered. This affects performance, method, wear and tear, resource consumption and, in many cases, the execution strategy itself.
From the bidding phase, this risk is reduced by improving the geotechnical basis of the project, clearly defining what information is considered contractual and establishing how unforeseen conditions will be assessed. It also helps to connect this review with site content on how unforeseen events or unexpected ground conditions are managed during the execution of the project. This topic is already part of Eurohinca's editorial ecosystem, according to the sitemap.
Risks due to permits, affected services and actual site availability
Another classic source of delays and controversies is that the project does not reach the bidding process with a sufficient level of definition of permits, affected services, occupancy, access or conditions imposed by owners of the infrastructure crossed. In these cases, the problem is not only technical: it is also contractual, because the deadline and price are built on assumptions that are not met.
To reduce this risk, it is advisable for the bidding process to define which permits have been obtained, which are still pending, which interferences have been verified and which operational restrictions are actually known. In trenchless works, many deadline extensions arise precisely from this difference between the assumed environment and the real environment. Eurohinca's own website already treats continuity of service and intervention in existing networks as a specific topic, which reinforces this pre-coordination dimension.
Risks due to incomplete definition of the scope and acceptance criteria
Conflicts are also common when the contract does not define precisely what is included in the scope of work and how the final result will be accepted. In microtunnelling, it is not enough to ask to “execute a crossing”: geometry, tolerances, pipe function, associated civil works, final documentation, tests and acceptance criteria must be clear. When these aspects are left open, there are different interpretations between the developer, the project management and the contractor.
Since the bidding process, this risk can be reduced by providing more detail on the deliverables, the controls required during the work and the contents of the as-built. The link to how quality control is carried out in a pile driving or microtunnelling project, because traceability of control is one of the best defenses against contractual conflict. The sitemap confirms that this content already exists on the web.
Timing risks due to implementation, logistics and execution sequence
In many projects, the lead time deteriorates not because of the machine, but because of an insufficiently studied implementation. Lack of space for attack and reception, inadequate access, incomplete civil works, logistical interferences or unrealistic sequences end up affecting performance right from the start. When these variables are not reviewed before bidding, the schedule is already stressed and any small incident becomes an accumulated delay.
The phase of technical assistance and engineering should be used precisely to check that the planned route can be executed with the means available and in the actual conditions of the site. On the Eurohinca site, this area appears as one of the value axes prior to execution.
How to reduce these risks from the bidding process
The most effective way to reduce contractual and term risks is to bid on a more closed technical basis and with clearer contractual rules. This implies improving the geotechnical information, verifying affected services, clarifying the status of permits, better defining the civil works and setting tolerances, tests, deliverables and acceptance criteria from the design stage. It is also advisable to resolve how changes in terrain, undetected interferences or external restrictions will be dealt with.
In other words, the more explicit the contract is about what is known, what is not known and how a deviation will be managed, the less room there will be for claims and conflicts. For a specialist company like Eurohinca, which has focused on microtunnels, tunnels and trenchless technologies since 1996, this prior clarity is consistent with its technical positioning and its accumulated experience in numerous executed sections.
Why good bidding protects time, cost and comparability of bids
A better defined tender not only reduces risk during the work. It also improves comparability between bids, because it limits the number of hidden assumptions that each bidder introduces in terms of price and time. This makes it possible to analyze proposals on a more homogeneous basis and reduces the likelihood that the apparently most competitive bid will end up being the most conflictive in execution.
In microtunneling, a bad bidding process tends to transfer uncertainty to the contract. A good bid, on the other hand, converts some of that uncertainty into manageable information. This is the best starting point to protect time, cost and quality before mobilizing equipment.
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