Excavator Resources
**Attention Plumbers**
Trenchless Utility Construction & Blocked Sewer Lines
A blocked sewer line may be the result of another utility line which was accidentally “cross bored” through a sewer line during the trenchless construction process.
When this happens it may take the sewer line a long time to become blocked and the excavator who caused the damage may be unaware of what has happened. If a sewer blockage is then cleared with mechanical clearing tools, there is a risk of cutting through the utility line which is causing the blockage.
This in turn could result in a loss of utility service, or if it is a gas or electric line causing the blockage, may result in serious injury or property damage.
When engaged in trenchless construction operations, limit the risk of a cross bore situation from occurring and reduce the risk of serious injury or property damage.
Contact 811 and other nonmember utility members in the area. It is very important to ascertain the location of sewer mains and laterals within the work area. If underground utilities exist in the area of the proposed bore path, pothole to ensure their exact location and depth and to verify that a cross bore does not occur. Before conducting a trenchless operation to install any type of facility, first contact 811 and non-member companies.
811 Click here for more information about the national call before you dig number.
New York 811, Inc. newyork-811.com
Dig Safely New York digsafelynewyork.com
Here are some useful resources for excavators and contractors
Excavator Handbook: NY811 Excavator Manual
Spanish Excavator Handbook: Coming soon
Promotional Items
New York 811 offers several safe digging promotional items for excavator and contractor use. For more information, contact one of our damage prevention liaisons.
Utility Color Codes
When utility company representatives mark a location, they use colored flags and/or paint to identify the type of underground service:

Color Example | Color | Definition |
---|---|---|
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Red | Electric power lines, cables, conduit and lighting cables |
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Yellow | Gas, oil, steam, petroleum or gaseous materials |
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Orange | Communication, alarm or signal lines, cables or conduit |
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Blue | Potable water |
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Purple | Reclaimed water, irrigation and slurry lines |
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Green | Sewers and drain lines |
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Pink | Temporary survey markings |
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White | Proposed excavating |
How Lines Are Marked




Time Frame Matrix
Plan ahead by using this simple diagram mapping out when to call 811 BEFORE you dig:
