When Do I Need Tennessee 811?
Call 811 before any digging project — it is free, it is the law, and it prevents damage to underground utilities.
Tennessee 811 is the one-call service that notifies underground utility operators to mark the approximate location of their buried lines before you dig. You should call 811 (or submit a request online) before any excavation project — no matter how small. This includes digging for plumbing repairs, fence posts, tree planting, or any project that breaks the ground. The service is free. Calling before you dig is required by Tennessee law and helps prevent damage to buried utility lines, injuries, and service interruptions.
Why This Matters
Underground utility lines — water, sewer, gas, electric, and communications — are buried throughout the Knoxville area. Digging without knowing where they are can damage a line, disrupt service to your neighborhood, cause injuries, and create legal and financial liability. Calling 811 is free, simple, and required by law. It is the single most important step before any excavation project.
How It Generally Works in the Knoxville Area
When you call 811 (or submit a request through the Tennessee 811 website), the one-call center notifies the utility operators that serve your area. Each utility sends a locator to mark the approximate location of their underground lines using paint or flags — typically within a few business days. Color codes: Locators use a standard color code: • Red — Electric • Yellow — Gas, oil, petroleum • Orange — Communications (telephone, cable, fiber) • Blue — Water • Green — Sewer and drain lines • White — Proposed excavation • Pink — Temporary survey markings After the lines are marked, you can dig — but you must hand-dig carefully within a specified tolerance zone around the markings. The tolerance zone varies but is typically 24 inches on either side of the marked line. Important: 811 only marks utility-owned lines. Private lines — such as a private water service line, a private sewer lateral, irrigation systems, or electric lines installed by a previous homeowner — are not marked through the standard 811 process. If you need private lines located, you may need to hire a private locator.
What 811 Marks vs. What It Does Not
811 Typically Marks
- • Utility-owned water mains and service lines (to the meter)
- • Utility-owned sewer mains
- • Gas lines owned by the utility
- • Underground electric lines owned by the utility
- • Communications lines (telephone, cable, fiber)
811 Does NOT Mark
- • Private water service lines (meter to house)
- • Private sewer laterals (house to main)
- • Irrigation systems
- • Landscape lighting wiring
- • Private propane or fuel lines
Private lines may require a separate private locating service. A plumber can help trace private water and sewer lines.
What the Homeowner Can Check
- Whether your project involves any digging or excavation — even shallow digging
- Whether you have called 811 or submitted a request before beginning excavation
- Whether the utility markings are still visible (they fade over time)
- Whether there may be private lines on the property that 811 will not mark
Who to Contact
Tennessee 811
Call 811 or visit the Tennessee 811 website to submit a locate request before any digging project.
Visit siteA Licensed Plumber
If your excavation project involves a water line or sewer line repair, a plumber can coordinate the 811 process and handle the excavation.
Learn moreWhat Not to Do
- Do not dig without calling 811 first — it is required by Tennessee law
- Do not assume you know where underground lines are — they may not be where you expect
- Do not assume 811 marks all buried lines — private lines are not included in the standard locate
- Do not mechanically dig within the tolerance zone of a marked line — hand-dig carefully instead
Still not sure who is responsible or what to do next?
Ask our AI Plumber — describe the problem and get guidance on whether it is likely on your side or the utility side.
Ask the AI PlumberVerify current requirements directly with the applicable authority.
Requirements may differ depending on whether the property is inside the City of Knoxville, elsewhere in Knox County, or served by another utility. Homeowners should verify current requirements with the applicable permitting authority before beginning work.
Common Questions
Is calling 811 really free?
Yes. Tennessee 811 is a free service funded by the utility operators. There is no charge to the homeowner or excavator for the standard locate.
How far in advance do I need to call?
In Tennessee, you should call at least 3 business days before you plan to dig. This gives the utility operators time to send locators to your property.
What if I am only digging a few inches down?
Call 811 for any project that breaks the ground, regardless of depth. Utility lines can be buried at very shallow depths, and shallow digging can still damage them.
If the problem involves your home's plumbing, The Classic Plumber can help.
We diagnose before we recommend — and we tell you when the issue is on the utility's side.