How To Find A Sewer Line Underground

3 Steps For Accurately Locating Your Underground Sewer Lines

How To Find A Sewer Line Underground

3 Steps For Accurately Locating Your Underground Sewer Lines

Sewer lines are everywhere.

From the sewer laterals in your yard, to the main sanitary sewer and storm sewer throughout your neighborhood, city, or jobsite, over 800,000 miles of underground sewers throughout the U.S. are located on public property. Another 500,000 sewer laterals are located on private property, so it’s no wonder why there’s such a great need to locate these underground utilities before digging. It’s important to know how to find a sewer line underground because if you don’t, and decide to dig, you’ll find yourself having to deal with leaking sewage [infiltration], a flooded property, and a large bill from the city with the cost of repairs once damages have occurred.

To avoid all that here are the three steps you need to get sewer lines on your jobsite marked, mapped, and inspected, so that you can dig, design, and build with confidence while avoiding the unwanted consequences of a damaged sewer system.

Three Steps for How to Find a Sewer Line Underground

Step 1: Check the As Builts

While this step is often a bottleneck for most contractors and design teams, checking as builts can give a rough idea about where a sewer line may be located. Unfortunately, many of these drawings are known to be outdated and inaccurate, but can give you a base point to start which can go a long way. The route, potential depth, and other property utility layouts can be included in these initial drawings. As-builts, however, should be taken with a grain of salt, as most of them could be called “as-intendeds” due to their consistent inaccuracy as shown in the image below.

As Intended vs. Accurate GPRS As Builts

Step 2: Call 811

By contacting your state’s 811 One Call hotline, you will be provided a free underground utility locate of all public utilities in the vicinity where work is being done. This is required by law anytime you dig or excavate. However, 811 does not provide depths of sewer lines, and, in some states, sewer lines are left unmarked and excluded from 811 dig requirements all together.

Step 3: Call A Private Sewer Line Locator

According to Forbes, 65% of all underground utility lines are located on private property throughout the United States. That means that on average, almost two out of every three underground utility lines (including sewer) will be deemed as private in your area of work.

And, since a public utility locator will not locate and mark these lines out for you, a private sewer line locator company such as GPRS can be called to help solve how to find sewer lines underground on your jobsite.

Good News For You

Sewers can be located at various depths depending on city code and what area of the country you live. Some are as deep as 3-6 inches for private lateral lines, while others can reach depths of 12-18 feet for public city sewer lines. The good news is, the majority of these lines can not only be located, they can also be visually inspected with video feedback utilizing CCTV robotic crawlers as shown in the image below.

CCTV Lateral Launch Camera provides live video feedback during inspection of unknown lateral line

How It Works

In the process of a CCTV sewer inspection, the private sewer line locator identifies any cleanouts, manhole covers, street storm inlets or other above ground visual indicators that would lead to access points to the sewer. Once identified, the locator can open the desired access point and select the proper piece of equipment to inspect the line.

Inspecting The Line

After the robotic crawler or push camera has been placed into the access point, the sewer line inspection can begin. Throughout the inspection, the CCTV camera head can provide live video feedback of the interior of the pipe while displaying any structural damages caused by clogs, blockages, breakage, corrosion, punctures due to cross bores, joint misalignments, seal cracks or leaks as shown in the video below.

Map & Mark the Location of Lines

Throughout the sewer line inspection, the Project Manager on hand can utilize the traceable sonde located on the top of the crawler’s camera head to accurately map and mark the sewer line from the surface with the approximate depth of the line being provided as well. This is completed with paint or other material on the ground, and the data is collected and uploaded into our accurate utility mapping software, SiteMap®, for your use once the locate and inspection are complete.

View Findings Within SiteMap®

Once the data has been collected and uploaded within the software, all it will take is a few minutes before you can view your findings within SiteMap®. This includes, but is not limited to, 99.8% data with displays of your geolocated manhole coverings, lateral lines, storm sewers, sanitary sewers, line depth, and video inspection reports attached to each line inspected as shown in the video below.

Our Equipment

Some of the different types of equipment utilized by GPRS Project Managers to accurately find and collect this underground data displayed within SiteMap® are as follows:

1. CCTV robotic crawlers: CCTV crawlers are robust and durable, enabling them to operate in extreme scenarios. Sewer line locator Project Managers at GPRS can provide accurate and reliable views of sewer pipelines and conditions because CCTV cameras can inspect pipes ranging from 6 inches to 96 inches in diameter.

2. Push Cameras: GPRS Project Managers are equipped with push cameras for smaller diameter pipe inspections. These cameras can be manually fed into a pipe and provide real-time video feedback. Push cameras have a locatable sonde for mapping purposes and are an ideal tool for scenarios where the pipe is too small for CCTV sewer inspections.

3. Lateral Launch Cameras: The lateral launch crawler allows GPRS Project Managers to inspect laterals from the mainline. This tool is capable of cross bore investigations and mapping the interior condition of hard-to-reach pipes, so that the 500,000 miles of private sewer lines in the U.S. can still be inspected.

4. EM Utility Locators: Electromagnetic pipe and cable locators use a rodder or sonde to emit a specific frequency, which the receiver then detects to precisely locate the underground utility above ground (in the case of sewer inspection, the frequency of the sonde is located on the head of the crawler or push camera).

While there are a few methods typically used to locate underground sewer lines, not everyone has access to these resources. At GPRS, we have an industry-leading nationwide network of SIM and NASSCO certified Video Pipe Inspection Project Managers who are dedicated to locating, inspecting, and mapping underground sewer systems to keep projects on budget, on time, and most importantly safe, any time sewer systems are involved. Our team utilizes all of the best-known practices and cutting-edge equipment to accurately locate, inspect, mark, and map sewer utilities.

We do this because we know that sewer line repairs and fixes caused by breaks and other damages can cause major issues for a project resulting in budget overruns, project stoppages, and even damaged reputation for the contractor at hand.

Trust the Industry Leader in Underground Sewer Inspections

GPRS is the industry leader in all 50 states for accurately locating sewer lines underground so that you can dig, design, and build with confidence.

If you need to map your municipality’s entire underground sewer system, or just locate a single lateral line before conducting directional drilling, GPRS is the underground sewer inspection company for you.

Mitigate the risk of sewer line damages when digging, drilling, or excavating by contacting a GPRS sewer inspection Project Manager, today.

Frequently Asked Questions

What size pipes can GPRS inspect?

We have the capabilities to inspect pipes from 2” in diameter and up.

Does GPRS Offer Lateral Launch Services?

Yes, we offer lateral launch capabilities for accurately locating your underground sewer lines.