An engineering map is a reference for engineers and contractors who may be involved with engineering projects. It can provide information about utilities, public works installations, and natural phenomena of concern. General reference maps may be maintained for an area by a government agency for the benefit of project planning. Custom maps can be produced in association with a specific proposal, and in some cases are required as part of an application to demonstrate that engineering tolerances and concerns have been considered in the planning process.
One example of an engineering map is a diagram of installations like power lines, sewer pipes, or phone lines. This type of map can be constantly updated to keep pace with developments. Utility engineers use such maps when setting up hookups, planning repairs, and addressing concerns. People who may need to work in the area can request a copy of the map so they know where it might be unsafe to dig or use chopping tools. For example, engineering maps at gas companies provide references on buried lines for construction companies.
Other maps can cover natural phenomena. These can include subjects like average wind speed, soil conditions, and rainfall. This kind of engineering map may be necessary for project planning; a structure in an area with high wind speeds, for example, needs to be designed with this in mind. Likewise, an engineering map may be used to determine if a facility can be built in a proposed location. Schools, for example, may be barred on ground that could be subject to liquefaction in an earthquake, due to safety concerns.
Preliminary engineering studies of a proposed building site may result in the generation of an engineering map to review the specifics of the location. The map provides information about observations on soil conditions and other issues that might play a role in building design. It can be part of an environmental impact statement used as part of a permit application. Engineers may need to show that it will be safe to build in a given location before they will be granted permission to move forward with construction.
Some maps are proprietary, and cannot be reviewed by members of the general public. Others are freely available and may be accessible online in some cases through county planning departments and similar agencies. The engineering map should include a key to help people decode what they see, along with notes to contextualize the data.