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Western Dam Engineering 10 Keep Specifications Tight and Relevant Technical specifications should be written and tailored specifically to the conditions expected to be encountered on the project, and should avoid the inclusion of unnecessary sections that are not pertinent to the project at hand. It may seem that the inclusion of every possible specification from 40 years of design practice would help cover any potential situation encountered during construction, but this would create a specification package so voluminous as to virtually guarantee that none of it would be comprehended or even read. Including unnecessary specification sections that are not relevant to the particular project just because they are part of a standard specification package, can make the project requirements confusing to the contractor. This results in higher bid prices to account for the uncertainty created. Worse yet, the requirements stated in unnecessary specification sections may actually contradict those of relevant sections, thus creating the potential for claims during construction. Similarly, vague specifications create uncertainty in the mind of the contractor, leading to high bid prices and/or construction claims. For dam projects, engineers should be careful to ensure that the requirements of the specifications, specifically regarding earthwork provisions, are consistent with locally available natural materials. It makes little sense to carefully describe the use of a particular type of material if it is not available in sufficient quantities nearby. Material specifications should be kept flexible enough to allow for some variability in the types of materials suitable for construction. In general, it will prove to be less expensive to use materials available on site that are suitable for construction than to import materials from off site. Use of Standard Specifications While the use of standard, prewritten specifications not specifically tailored to the particular dam project is generally discouraged, it may be useful at times to utilize minor extractions from standard specifications where applicable. Any standard specifications so used should be included within the published specifications for the project and not merely attached by reference. This allows both the contractor and construction inspector to readily refer to the specification in the field, and reduces the risk of unintentional noncompliance with the requirements of the specification. Care should be taken that any standard specifications included in the bid package are relevant to the work at hand and do not conflict with the requirements of proper dam construction practices. For example, the use of department of transportation or public utility type specifications for earthwork construction on dams may not be applicable, appropriate, or acceptable to regulatory agencies. The major federal agencies who maintain a role in the design, construction and operation of dams in the United States, such as the Bureau of Reclamation, U.S. Army Corps of Engineers, and the Natural Resources Conservation Service, have all developed what might be referred to as standard specifications for dam construction, and these should be consulted first among standard specifications for use in a specifications package. A listing of references on standard specifications available from these entities is included at the end of this article. These may provide a useful starting point for the design engineer to modify for the project-specific requirements. Each of the federal agencies listed above employs a somewhat different approach to specification writing, so, if one of those standards is used, it is important to be consistent with the way that standard was developed, or extract the information into the format being used for your project. The NRCS standard specifications, for example, are based on “parent” specifications which cover a wide range of general requirements and possible materials and processes for each technical specification section that are written as general requirements applicable for all projects. Each specification section then requires a project-specific “Items of Work and Construction Details” or a “Special Provisions” subsection to be included at the end to narrow down from the standard spec to specifically what materials and processes are required or allowed for the particular project. This format of incorporating a concise listing of project specific requirements in one section at the end of the standard specification is important when using this “parent spec format”. The more common approach in private practice is to develop a specification package written tailored to the given project in its entirety.