Virtually all civil engineering structures are unique. They have to be designed for some specific purpose at some specific location before they can be constructed and put to use. Consequently the completion of any civil engineering project involves five stages of activity which comprise the following:
1. Defining the location and nature of the proposed works and the quality and magnitude of the service they are to provide.
2. Obtaining any powers and permissions necessary to construct the works.
3. Designing the works and estimating their probable cost.
4. Constructing the works.
5. Testing the works as constructed and putting them into operation.
There are inherent risks arising in this process because the design, and therefore the estimated cost of the works, is based on assumptions that may later have to be altered. The cost can be affected by the weather during construction and the nature of the ground or groundwater conditions encountered. Also the promoter may need to alter the works design to include the latest technical developments, or meet the latest changes in his requirements, so that he does not get works that are already out-of-date when completed. All these risks and unforeseen requirements that may have to be met can involve additional expenditure; so the problem that arises is who is to shoulder such additional costs?
Clearly if the promoter of the project undertakes the design and construction of the works himself (or uses his own staff) he has to meet any extra cost arising and all the risks involved. But if, as in most cases, the promoter engages a civil engineering contractor to construct the works, the contract must set out which party to the contract is to bear the cost of which type of extra work required. The risks involved must also be identified and allocated to one or the other party.