The nationally recognized color code system for utility locating provides a universally accepted system for engineers, facility managers and construction workers to be able to understand the type of utility that may be hidden under the ground, in walls or behind concrete.
When working in a mark-out area proceed with caution. Flags and paint markings are placed with the use of sophisticated utility locating equipment. Utility Survey Corp. uses advanced Ground Penetrating Radar (GPR), Radio Frequency location equipment and other devices in an effort to determine the type and depth of hidden obstacles.
Although markings are placed based upon the best understanding of the equipment, output inaccuracies can occur due to equipment limitations and other factors. Do not make assumptions about the continuation of a mark out beyond the bounds of the survey area.
How will these colors will impact your next project? Read our blog entitled Utility Markouts - 6 Colors (And Why They Matter to You) to find out.
Communication utilities include telephone, TV, internet, etc. They can be fiber optic cables or conventional coaxial cables.
Electrical power cables/conduits buried underground, especially those high voltage ones, are great hazards for excavating, drilling and other ground intrusive activities. Sometimes they are protected in duct banks, but most times they are not. Electrical conduits embedded in concrete floors also put people at risk during concrete cutting, drilling or coring.
Explosions and fire are the potential outcomes if natural gas, oil or petroleum pipes are hit by something like an excavator or a drilling rig. Due to high temperatures and possibly high pressures, a steam pipe also contains hazards ready to strike if it’s broken. Ground intrusive activities around these underground utilities are very dangerous.
The sanitary sewer is a system of underground pipes that carries sewage from bathrooms, sinks, kitchens, and other plumbing components to a wastewater treatment plant where it is filtered, treated and discharged. The storm drain is a system designed to carry rainfall runoff and other drainage. Usually they are not mixed with each other to avoid excessive loads for wastewater treatment. This is also the reason why you should not dump unsanitary water or other wastes into a storm drain system since it will flow into the environment without being treated.
The type of a utility can be determined in a number of ways by observing where it starts/ends, characteristics of the tracing signals, ground features (valves, manholes), utility plans, etc. Despite all of these, sometimes the type of a utility cannot be determined due to limited information available. They are usually marked using a color (such as purple or pink) which is not used by known utilities.
Water pipes supply water to domestic and fire protection systems. To reduce the risk of getting damaged by extreme cold weather, usually they are buried below the frost line to prevent them from freezing. As a result, a water pipe is usually buried around or deeper than 4 feet in the great New York City area.