FREQUENTLY ASKED QUESTIONS

GPR scanning is exceptionally effective at locating all types of subsurface materials. There are times when PVC pipes do not provide an adequate signal to ground penetrating radar equipment and can’t be properly located by traditional methods. However, GPRS Project Managers are expertly trained at multiple methods of utility locating.

In most circumstances, we can have a Project Manager on your site within 24 hours of contact. Click here for an online quote form.

GPRS robotic crawler cameras have a reel length of 1,000 linear feet. We typically inspect miles of the pipeline but can check 1,000 linear feet from any point continuously.

Yes, ground penetrating radar can be used to determine the location of unmarked graves for site planning purposes. We are able to locate most grave sites, even those that have experienced material decomposition.

GPR is used to identify the location of subsurface materials. GPRS uses this radar for utility locating and concrete scanning applications. Varying antenna strengths are used for different applications, depending on the type of material being scanned and how deep objects are buried.

Our nationwide team of Project Managers can meet your scheduling needs. We are willing to work nights and weekends, in addition to regular working hours, to help you accomplish the goals of your project. Contact your local GPRS representative to learn more about our rates and availability.

We regularly use GPR equipment to scan for the location of rebar in concrete columns and walls. GPR can also examine the underside of a floor to mark out the reinforcing steel and any embedded conduits.

The Green Box Guarantee is simple: when a GPRS Project Manager places a Green Box within a layout prior to anchoring or coring concrete, we guarantee the area will be free of obstructions. If we’re wrong, we’ll pay the material cost of the damage.

GPR is extremely effective at locating subsurface utilities and other materials, however it does have certain limitations. Ground and soil conditions, weather, and the type of material being located are just a few of the potential limiting factors. In the event that conditions are not suitable for GPR scanning, an alternative recommendation can be made.

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GPR on its own does not tell you what type of object has been located, which is why it is inadvisable to attempt to complete this type of work yourself. Fortunately, GPRS Project Managers are uniquely equipped to interpret the data collected by a GPR scanner to identify the type of embedded material present. Every GPRS Project Manager is required to complete the Subsurface Investigation Methodology (SIM) training program, which involves 320 hours of field training and 80 hours of classroom training. Through this regimen, our Project Managers tackle real-world scenarios in a safe and structured environment where they can learn to tackle these challenges with the highest level of accuracy and professionalism.

Yes, our professional Project Managers can respond rapidly to emergency same-day private utility locating service calls on your job site.

GPRS uses paint, flags, markers, and other methods to mark locations depending on the surface. We can also use specified methods upon request.

The GPRS Green Box Guarantee emphasizes four critical project factors: safety, efficiency, cost savings, and clear communication. Each benefit comes together to enhance our 99.8%+ accuracy rating and allows clients to join in our fight to eliminate subsurface damage.

When you break ground on a new project before doing a private utility locate, you’re playing Russian Roulette. You may be lucky the first time, but what about the next time?

According to a report published by the Common Ground Alliance (CGA), the direct and indirect costs of damage caused by strikes totaled around $40 billion in 2021 alone, with the privately funded Infrastructure Protection Coalition putting the figure closer to $61 billion.

Over 60% of all buried utility lines are private, meaning they’re owned by individuals or businesses. If you don’t hire a private underground utility locator to identify these lines in your project area prior to digging, you run the risk of knocking out power to an entire neighborhood, creating a water emergency for a municipality, or causing serious injury or death with a gas line explosion or electrical line strike.

GPR is exceptionally accurate! While accuracy depends on various external factors such as ground and soil conditions, the GPRS standard ensures that we can obtain the best results possible in each situation. Through experience, we've found that when using a concrete antenna for scanning, the accuracy is typically +/- ¼" to the center of the object and +/- ½" to the actual depth. When locating an object using a utility locating antenna for scanning, the accuracy is +/- 6" to the center and +/- 10% to the actual depth.

The results of the concrete antenna are generally higher resolution and therefore considered to produce better quality results. However, the concrete antenna cannot penetrate the ground as deeply as the utility locating antenna. It is critical to understand the benefits and limitations of both when performing scanning work.

We are able to use GPR to cross-check the measured depth and location of a located utility with existing as-built plans in order to verify the accuracy of plans.

In post-tensioned structures, we typically find one mat of support rebar near the base of the slab. This mat is generally consistently spaced and remains at a constant elevation. Post-tension cables are generally found above this support mat and “draped” throughout the rest of the structure. The elevation of the cable is usually high near the beams and column lines and drapes lower through the span between beams and column lines. Knowledge of these structural differences allows us to accurately differentiate between components. Our Project Managers will leave you feeling confident in our findings and in your ability to drill or cut without issue.

In most situations, we can identify the utility in question without any problems, although it is not always possible to determine what type of utility is present. When this happens, we attempt to trace the utility to a valve, meter, control box, or other signifying markers to determine the type of utility buried.

Subsurface Utility Engineering (SUE) reduces the risk and improves the accuracy of subsurface utility readings. It is broken down into four levels of quality, governed by ASCE Standard 38-02. GPRS provides private utility locating services but does not currently provide a fully comprehensive in-house SUE service. GPRS does not provide engineering services. If you need professional engineering services, please contact a professional engineer.

GPRS Project Mangers undergo a rigorous training program to ensure you have the most reliable and accurate infrastructure visualization services at your disposal. This includes the Subsurface Investigation Methodology (SIM), which consists of 320 hours of field training and 80 hours of classroom training during which Project Managers tackle real-world scenarios in a safe and structured environment.

The 811 service is a public service invented to locate public utility lines. However, 811 does not perform locates on private utilities meaning that private owners will typically need to call in a private locator such as GPRS. GPRS locates both public and private utilities.

Ground penetrating radar (GPR) is a safe, non-invasive tool used to identify subsurface objects. GPR does not emit any harmful radiation or other byproducts. The scanning process does not create any noise, and the area can remain undisturbed during the scan. Contact us with any questions regarding the safety of GPR usage. We are happy to provide you with additional documentation.

Each of Project Managers completes a three-month training process which includes two weeks at our Training Center in Sylvania, Ohio. The highlight of the state-of-the-art GPRS Training Center is its roughly 6,000-square-feet of dedicated test slab created to simulate most conditions encountered in the field. This test slab is riddled with buried utilities designed to provide an immersive test experience for our Project Managers-in-training. As part of the GPRS training regimen, each Project Manager is trained per the Subsurface Investigation Methodology (SIM), which consists of 320 hours of field training and 80 hours of classroom training.

When you’re excavating for a new structure or renovating an old building, there are countless subsurface hazards that need to be accounted for prior to excavation, core drilling or saw cutting.

If you choose not to schedule Concrete Scanning Services, the result could be detrimental to your job site or company. There are compounding effects that could impact safety performance, project schedules, and job site financials that could delay or cancel the entire project.

We are the best at what we do because it is all we do. When you are faced with the need to know what lies below the surface, contact the nation’s best utility and concrete scanning company. Your project’s success could depend on it.

GPRS uses a variety of ground penetrating radar and scanning tools according to a project's needs. Our two most used pieces of equipment are the concrete scanning antenna and the utility locating antenna. Read more about the different types of equipment we use here.

No, GPRS will locate and mark all utilities for you. We have a variety of tools and markers we can use to highlight the locations of utilities, underground storage tanks and whatever else may be hiding.

There are many benefits to utilizing concrete scanning services in your next project. Taking precautions like concrete scanning or utility locating can help keep your project on time, on budget, and safe.

If you fail to schedule a concrete scan and damage an unknown utility during an excavation, this is often costly to fix. The expense of these unnecessary repairs results in a loss of time and budget.

After analyzing thousands of previous leaks detected, we asked clients to send us pictures of the remediation. This information has helped us compare our final leak signal detected with the results of the actual leak. We determine the size of the leak by how far the leak signal travels between contact points and the pitch of the tone received. However, we do not produce formal leak estimations.

No. GPR equipment can identify the area where a void is occurring and the boundaries of that void. It cannot measure the void’s depth.

Our Project Managers flag and paint our findings directly on the surface. This method of communication is the most accurate form of marking when excavation is expected to commence within a few days of service. GPRS also uses a global positioning system (GPS) to collect data points of findings. We use this data to generate a plan, KMZ file, satellite overlay, or CAD file to permanently preserve results for future use. GPRS does not provide land surveying services.  Here are the deliverables offered by GPRS:

• PHYSICAL FLAGS OR MARKINGS: Clients often receive field markings in the form of paint, pin flags, stakes, or any other method they request. GPRS trains our Project Managers to ensure that all the field markings they apply are clear and easy to understand.
• KMZ AND PDF MAPS: PDF files are images that visually communicate what utilities are located where. Think of a PDF file as a physical paper map that you can view on a computer or mobile device. KMZ files, on the other hand, are tagged with geolocated points that indicate specific utilities, pipes, lines, and other features. GPRS offers a complimentary PDF and KMZ map with every utility locating project.
• CAD RENDERINGS/3D MODELS: CAD files can be 2D or 3D renderings of a space. CAD drawings allow contractors, engineers, and owners to develop or update as-built drawings. Clients use these files for pre-planning, to avoid utilities, or to document the history of their site on various CAD and GIS systems.
• SITEMAP GIS SOFTWARE: Utility maps are stored in GPRS SiteMap by uploading field-verified data, including detailed, layered utility maps, into the platform's secure cloud-based digital storage. GPRS collects this data through various methods, including GPS, to create digital files like KMZ or CAD files, which are then uploaded to SiteMap for clients to access, store, and share.

GPR is highly effective at locating subsurface utilities and other materials. However, it does have certain limitations. Performing locating services on suboptimal ground and soil conditions, inclement weather, and the material of the object being located are just a few potential limiting factors. We can provide alternative recommendations if conditions are unsuitable for GPR scanning.

Please visit our sales page to request a quote.

We can use ground penetrating radar equipment on concrete masonry unit (CMU) walls and structures. GPR can also determine the presence or absence of grout, bond beams, vertical rebar, horizontal rebar, and joint reinforcing within the CMU structure.

GPRS's leak detection service is used to help municipalities and facilities maintain safe, efficient water distribution within a pressurized domestic supply network and fire protection systems. Often, water can leak from aging or broken infrastructure, creating unnecessary costs for clients. GPRS locates these water leaks, allowing our clients to reduce the number of costly excavations required for remediation.

This answer depends on the type of application. The antenna can typically penetrate 18”-24” into the ground for concrete scanning. For private utility locating needs on grass, asphalt, or concrete, the antenna can generally penetrate up to 8' but this can vary greatly depending on site conditions.

In certain situations, a larger antenna can be used for greater penetration. Please contact your local GPRS representative for more information on selecting the right GPR service for your project.

GPRS provides two specific but different scanning services: elevated concrete slab scanning and concrete slab-on-grade locating. Elevated concrete slab scanning involves detecting embedded electrical conduits, rebar, post-tension cables, and more before core drilling a hole through the slab. Performing a concrete slab-on-grade locating service typically involves scanning a trench line for conduits before conducting saw cutting and trenching to install a sanitary pipe, water line, or something similar.

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GPRS uses various methods and equipment to locate utilities due to soil composition, geographical location, and other factors. These methods include EM Locators, Electromagnetic Induction, Push Cameras, Robotic CCTV Crawlers, Magnetometers, Acoustic Leak Detectors, Sondes, and more.

Our acoustic listening equipment is highly sensitive and amplifies leaks and other noises which mask leak signals during the day. If we work in city environments, there is often a significant amount of ambient noise. This noise includes airplanes, traffic, mowers, machinery, and most importantly, people using water. It is up to the Leak Detector to determine if night work should be utilized to minimize all other noise to focus on the leak signal.

The Green Box Guarantee is designed explicitly for elevated concrete slabs, indicating areas free of obstructions such as rebar, post-tension cables, and electrical conduits. While the Green Box Guarantee does not apply to all concrete, utility, and video pipe inspection jobs – we stand by our work. We have a 99.8%+ accuracy rate on over 400,000 projects completed, and we continue to pursue 100% subsurface damage prevention.

The GPRS difference goes much deeper than a simple FAQ. Please, read our Statement of Qualifications document to learn about all the attributes that make GPRS the industry leader.

GPR is used to identify the location of subsurface materials. GPRS uses this technology for utility locating and precision concrete scanning applications. We utilize varying antenna strengths for different applications, depending on the scanned material and how deep objects are buried.

Locates is a term used in the utility locating industry meant to describe a locating service. Utility locates are services where a utility locating company will use ground penetrating radar and other methodologies to reveal subsurface hazards and obstructions.

GPRS is an industry leading private utility locator. Please contact us to schedule a service.

No. Our green boxes communicate to our clients that all critical targets such as rebar reinforcement, electrical conduits, and post tension cables are absent, and no obstruction is present. We place green boxes on elevated concrete slab locations that we’re confident are clear to core, cut, or drill through. If we aren’t confident that you won’t hit anything, we won’t place a green box on the slab.

We can typically differentiate between tendons versus rebar in post-tension slabs due to the expertise of our Project Managers. Their rigorous training helps them recognize the differences in patterns, depth, spacing, and GPR reflections. Because all of our Project Managers are SIM-certified, they’re experts with their equipment, professionally trained, and up-to-date on the most effective GPR methodologies.

GPRS strongly believes that our team members are the key to our sustained success over our 20+ years in business. We look for certain qualities that set us apart from the competition when hiring new team members, because we only want the best representing our brand and helping you keep your projects on time, on budget, and safe. Our strong sense of integrity, proven competency in our field, and commitment to our customers are just a few of the qualities that make GPRS a cut above the rest.

Our nationwide team of Project Managers is strategically placed in every major market in the country, so you always have precision concrete scanning, utility locating, 3D laser scanning, video pipe inspection, leak detection, and mapping & modeling services near you.

No, the Green Box Guarantee is an industry-leading, proprietary program GPRS created to help prevent injuries and damages. We want to provide you with the peace of mind that comes with knowing you and your team can safely core and drill into concrete without worrying about subsurface damage. GPRS offers this program as part of our pursuit of 100% subsurface damage prevention. We are the only company that can provide the Green Box Guarantee, because we’re the only company that can lean on our industry-leading 99.8%+ accuracy rate for concrete scanning projects.

We have developed a rigorous leak detection methodology. We are confident in our leak location markings if all criteria are met using our available technologies.

Ground penetrating radar is a detection method that uses radio waves to identify buried or hidden objects within a structure or beneath the surface. This non-destructive method uses antennas of varying strengths to transmit a signal into a surface. As the signal encounters different components within that surface, it is bounced back to a receiver at the surface. This action helps determine the location of buried utilities and other subsurface features.

Yes, we buy used equipment from other GPR companies. Please call our corporate office at 419-843-9804, and we would be happy to discuss equipment sales. We routinely service and calibrate equipment to ensure the most accurate results for your project.

Contact GPRS by phone or through our website, and a local GPRS representative will be in touch with you as soon as possible. Our representatives and local Project Managers are skilled in assessing local conditions and can help you figure out how GPR services can meet your needs.

The amount of pipe we can test often depends on the experience of the Leak Detector. Team members with many years of experience can test up to 10 miles of pipe a day on a metallic system (Cast Iron/Ductile). Experienced Leak Detectors can test a contact point (Hydrant/Valve) within a minute before moving on to the next one. Leak Detectors can work efficiently because they are trained to hear the specific tone that a leak produces compared to any other number of noises a general environment makes.

Water finds the path of least resistance. Water can run through cracks in subsurface rock or make its way into storm, sanitary, and conduit piping. If the subsurface contains a high volume of sand, it will naturally flow farther down. There is no water visible on the surface in more than 99% of the leaks we locate.

No company can match GPRS’ comprehensive suite of infrastructure visualization services, which include utility locating, precision concrete scanning and imaging, 3D laser scanning, video pipe inspection, leak detection, drone photogrammetry, and mapping & modeling.

And no company can match our nationwide network of highly-trained Project Managers who are able to respond to your job site, no matter where it’s located, usually within 24 hours of contact.

Most importantly, nobody can match our dedication to the safety of you and your team. Contact us today to experience the GPRS difference yourself.

To locate underground utilities safely and effectively, the locator must be adequately trained on GPR methodologies and equipment. If handled incorrectly, accidentally striking a utility can be costly, damaging, or even fatal. Our Project Managers are SIM-certified meaning they are experts on GPR equipment and up-to-date on the latest GPR methodologies.

We can deliver 3D laser scan data in many formats, including:

• Point Cloud Data (Raw Data)
• 2D CAD Drawings
• 3D Non-Intelligent Models
• 3D BIM Models
• JetStream Viewer

Customizable Deliverables Upon Request

• Aerial Photogrammetry
• Comparative Analysis
• Deformation Analysis
• Digital Drawings of GPR Markings
• Floor Flatness Analysis/Contour Mapping
• New Construction Accuracy Analysis/Comparative Analysis
• Point Cloud Modeling Training Webinars
• Reconciliation of Clients 2D Design Drawings
• Reconciliation of Clients 3D Design Model
• Structural Steel Shape Probability Analysis
• Template Modeling
• Volume Calculations
• Wall Plumb Analysis

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Almost any project that requires as-built information can benefit from a laser scanning survey. Talk with our experts and start your 3D laser scanning survey project today.

A utility locate identifies and marks the position of underground utilities on-site using flags or paint. A utility map, by contrast, is a digital or physical record that documents the location and depth of these utilities for future reference. Mapping often follows a locate and provides a permanent, georeferenced record. GPRS does all three: We do a surface mark-out, provide you with a free PDF and KMZ file of your utility map overlaid on a satellite image, and deliver an interactive, layered utility map via SiteMap, so you have your findings available from anywhere, 24/7, in a secure shareable platform.

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811 services only mark public utilities, i.e., those owned and maintained by utility companies. They do not identify private or unregistered utilities, which include all lines beyond the meter or on private property. To avoid costly damage or safety risks, private utility locating services like GPRS are essential for a complete picture.

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Striking a utility line can result in serious injury, service disruptions, environmental hazards, and legal liability. Damaging a gas or electric line, for example, can lead to explosions or electrocution. And hitting a water main can cause an entire community to lose access to fresh water. Any utility strike puts your workers, the project, and your reputation at risk. Prevention through accurate locating is critical to project success

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Real-Time Kinematic (RTK) positioning is a high-precision geo-positioning method that uses satellite correction data to achieve centimeter-level accuracy in the right conditions. In utility locating, RTK ensures that mapped utility data is geospatially accurate, enabling precise excavation and long-term asset management.

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Utility locating is the detection of underground utilities and other subsurface findings using ground penetrating radar (GPR) and other tools. Utilities and other findings can be located and marked out in a safe, non-destructive manner.

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Electric, steam, telecommunications, water pipes, gas & oil pipes, sewer pipes & storm sewer lines, and many other primary and secondary utility services can be located.

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The cost of a private utility locate varies depending on the size and specifics of the site being scanned, as well as other factors. Utility locates are a vital service and significantly less expensive than the cost – both financial and otherwise – of striking a utility line.

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The American Public Works Association (APWA) has established a universal color code to differentiate various utilities:

• Red – Electric power lines, cables, and lighting cables
• Orange – Communication, alarm, signal lines, and fiber optic cables
• Yellow – Gas, oil, steam, petroleum, and other flammable materials
• Green – Sewer and drain lines
• Blue – Potable (drinking) water
• Purple – Reclaimed water, irrigation, and slurry lines
• Pink – Temporary survey markings
• White – Proposed excavation area

Utility locating is a critical step in construction planning that helps prevent costly damage to underground infrastructure, enhances worker safety by avoiding hazardous utility strikes, and ensures compliance with regulatory standards. By accurately identifying the location of buried utilities, GPRS enables project teams to reduce legal liabilities, minimize delays caused by unexpected obstructions, and maintain efficient workflows. A thorough utility locating process supports safer, smarter, and more cost-effective construction execution.

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Yes, it can. Unlike with X-ray, where both sides of a concrete slab must be accessible to obtain a picture of the subsurface structure, GPR only requires access to one side of a slab to obtain a comprehensive view of what’s inside the slab. This makes it an ideal technology for evaluating concrete slab-on-grade.

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When operated by our highly trained Project Managers, GPR’s typical accuracy is +/- ¼” to the center of the object in concrete we locate: conduit, post tension cables, and rebar. We can also pinpoint the depth of every object we locate in concrete with an accuracy of +/- 10-15%. Because our accuracy while scanning with GPR is so high, we can offer you our professional opinion to help you know where you are able to drill without the risk of hitting any objects marked on the slab. For safety concerns, we always tell our contractors to move one-to-two inches from any marked line as they prepare to cut or drill to be sure they safely miss any embedded objects. We are so confident in the accuracy of our Project Managers that we introduced the Green Box Guarantee, which states that when we place a Green Box within a layout prior to you anchoring or coring concrete, we guarantee that area will be free of obstructions. If we’re wrong, we will pay the material cost of the damage.

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Ground penetrating radar is an extremely efficient and rapid technology. Large areas can be easily and quickly scanned with the state-of-the-art GPR units utilized by GPRS Project Managers. Our standard layout for a typical core drilling location is 2’x2’. It usually takes about 10 minutes to scan and mark an area this size.

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In post-tensioned structures, we typically find one mat of support rebar near the base of the slab. This mat is generally consistently spaced and remains at a constant elevation. Post-tension cables are generally found above this support mat and “draped” throughout the rest of the structure. The elevation of the cable is usually high near the beams and column lines and drapes lower through the span between beams and column lines. Knowledge of these structural differences allows us to accurately differentiate between components. Our Project Managers will leave you feeling confident in our findings and in your ability to drill or cut without issue.

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Concrete scanning is critical for ensuring safety on construction sites. Damaging rebar or post-tension cables during drilling or cutting can compromise structural integrity, potentially leading to immediate failure and serious injury or death. Additionally, severing hidden electrical conduits poses a risk of electrocution, which can also be fatal. Proper scanning helps prevent these hazards, protecting both workers and the structure.

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Yes, GPR is a non-destructive tool for penetrating concrete to determine what is inside of it. GPR can be used to detect any non-concrete material or voids within the concrete.

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Yes, GPR can scan for the location of rebar in concrete columns and walls. It can also scan the underside of a floor to mark out the reinforced steel and any embedded conduits.

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Reality capture is the process of digitally documenting physical environments using technologies like 3D laser scanning and photogrammetry. It produces accurate spatial data that can be used to create models, maps, and visualizations for design, construction, and facility management.

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GPRS uses LiDAR-based 3D laser scanning and photogrammetry to collect millions of data points on any site to document its existing conditions. The data is processed into point clouds and can be converted into 2D CAD drawings or 3D BIM models, enabling precise planning and coordination across disciplines.

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No. Reality capture is the process of collecting spatial data from the physical world. A digital twin is a dynamic, data-rich virtual replica of a physical asset that integrates real-time data and analytics. Reality capture provides the foundational geometry for a digital twin, and GPRS can provide both, tailored to your needs.

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GPRS delivers construction-grade accuracy using high-resolution LiDAR scanners and survey-grade controls and registration. Accuracy depends on site conditions and equipment, but typically achieves tolerances within 2 to 6 millimeters, suitable for clash detection, prefabrication, and as-built documentation.

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3D photogrammetry is a technique that uses overlapping photographs taken from multiple angles to reconstruct three-dimensional models. It relies on computer vision algorithms to triangulate spatial coordinates (also known as orthomosaic imaging and registration), to produce textured 3D meshes, walkthrough virtual tours or point clouds for visualization and measurement. GPRS can integrate subsurface feature markings via photogrammetry and integrate them into a full above and below-ground CAD drawing or BIM model, as required.

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Point clouds provide powerful and dynamic information for a project. By representing spatial data as a collection of coordinates, point clouds deliver large datasets that can be mined for information. The visualization and analysis from this data is invaluable for decision making. CAD technicians transform point clouds into customized deliverables used for visualization, analysis, design, construction, renovation, prefabrication and facility modifications.

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With Project Managers all over the US, we work quickly to provide detailed quotes for clients. For most jobs, large areas can be laser scanned in as little as a couple of hours or larger sites in as little as a few days. Entire facilities or campuses can take several weeks to capture the entire site, but most projects are measured in hours or days.

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After 3D laser scanning a project site, the next step is to process the raw point cloud data by registering the individual scans together, cleaning up any noise, and then converting it into a usable format like a 3D model or 2D drawing. The processing of point cloud data can be for tasks ranging from simple visualization to detailed 3D modeling, depending on the project's requirements.

The GPRS processing workflow was developed with an understanding of the importance of precision, collaboration, and planning in architecture, engineering, and construction projects. By leveraging 3D laser scanning equipment and software and a well-structured team approach, GPRS ensures efficient project execution and high-quality deliverables tailored to each client’s needs.

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Black and white targets on fixed-height tripods are often placed at control points, benchmarks, or magnails so that they can be easily identified and scanned by the laser scanner. The scanner records the locations of these targets, and software later uses this data to correct and align the scans.

Silbaugh outlined that GPRS Project Managers primarily use targetless scanners, though they deploy targets in specific scenarios:

• Survey Control: Targets are used when tying into survey control provided by the client.
• Integration of Multiple Equipment: For instance, when integrating data from the NavVis VLX with other laser scanners, targets help align multiple datasets.

Targets allow laser scan data to be aligned with survey control points or a global coordinate system and aid in registering (aligning) data from multiple 3D laser scanners accurately.

The registration process is a collaborative effort. Registering a 3D laser scan point cloud involves aligning multiple scans of the same area taken from different positions into a single, coherent point cloud. This typically involves using specialized software like Autodesk Recap to import the data and align the scans. The Mapping & Modeling Team uses the software to find overlapping areas between different scans where the same physical features are captured from slightly different angles, allowing the software to identify corresponding points.

Silbaugh says unwanted “noise” can be cleaned or deleted from the point cloud. Autodesk Recap software can isolate and delete extraneous data or noise, such as reflections, moving objects, or background clutter, leaving behind a refined point cloud representing the desired project area. Proper registration ensures that measurements taken from the 3D laser scans are accurate and the data can be exported for use in CAD or BIM applications like Revit or AutoCAD.

GPRS does not clear blockages or offer hydro jetting services. We do, however, identify blockages and defects using advanced inspection tools. Our role is to locate and document obstructions so that appropriate remediation can be planned.

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GPRS uses robotic crawler cameras, lateral launch systems, and push cameras to capture high-resolution video and spatial data. These tools are supported by WinCan reporting software and the NASSCO-certified reports are delivered via SiteMap® (patent pending).

We can help find Illicit sewer access points by inspecting for unauthorized connections, structural anomalies, or flow irregularities. This is most often accomplished via smoke testing or dye tracing in concert with a video inspection, to pinpoint illicit tie-ins with visual confirmation and geospatial data.

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NASSCO stands for the National Association of Sewer Service Companies, the leading authority setting standards for the assessment, maintenance, and repair of sewer systems. There are three key NASSCO certifications and GPRS’ VPI Project Managers are certified in all three:

• PACP (Pipeline Assessment Certification Program): Standardizes how pipeline defects are identified and graded using CCTV inspections.
• MACP (Manhole Assessment Certification Program): Focuses on evaluating manhole conditions.
• LACP (Lateral Assessment Certification Program): Covers inspection of lateral sewer lines.

GPRS’ NASSCO-certified VPI reports ensure consistent defect grading, terminology, and documentation to support regulatory compliance and informed decision-making.

A cross bore is an unintended intersection of a utility line with a sewer or drain line, often caused by trenchless directional drilling. According to the Cross Bore Safety Association, there are more than one million undiscovered cross bores intersecting other sewer utility lines throughout the U.S. They present serious safety risk, and are often found through video inspection. That’s why GPRS strongly recommends pre and post-cross bore inspections whenever trenchless technology is being deployed.

A sewer inspection camera is a tool used to assess the condition of underground sewer lines without excavation. It consists of a high-resolution camera mounted on a flexible, durable cable that is fed through the pipeline. As the camera travels through the sewer system, it transmits real-time video footage to a monitor, allowing technicians to visually identify blockages, structural damage, root intrusion, and other issues.

Many systems are equipped with sonde transmitters or locating technology, enabling precise surface marking of problem areas. This facilitates targeted repairs, reduces unnecessary digging, and significantly improves efficiency and cost-effectiveness in both residential and commercial plumbing operations.

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Sewer camera inspections are a critical diagnostic tool for identifying underlying issues in sewer systems that may not be visible through standard methods. These inspections help detect chronic clogs, aging or deteriorated piping, tree root intrusions, foreign object blockages, leaks, and misaligned or poorly installed sewer lines. Common indicators that warrant a video pipe inspection include recurring backups in toilets or drains, slow drainage in sinks and showers, unexplained soggy patches or puddles in grass, and foul odors emanating from drains or outdoor areas. By providing precise visual data, sewer camera inspections enable faster, more accurate repairs and reduce costly guesswork.

Sewer line video inspection is a non-invasive, highly effective solution for diagnosing underground utility issues without disrupting operations or damaging property. GPRS utilizes advanced high-resolution camera technology to perform real-time visual assessments of sewer infrastructure, identifying problems such as leaks, blockages, corrosion, root intrusion, and misaligned piping. This precision-driven approach eliminates the need for costly excavation and manual inspections, accelerating project timelines and reducing repair expenses. By delivering accurate, actionable data, GPRS empowers facility managers, contractors, and engineers to make informed decisions and implement targeted solutions with confidence.

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GPRS identifies and pinpoints leaks using a combination of complementary technologies and processes: acoustic leak detection, leak correlators, sondes and other methods. Acoustic sensors detect sound frequencies emitted by pressurized leaks in water or gas lines. Correlators analyze time delays between grounded sensors to help pinpoint leak locations. These methods are non-invasive and highly accurate for both pressurized and non-pressurized systems.

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Leak surveys can be conducted with specialized acoustic microphones, ground sensors, digital leak correlators, and tracer gas detectors. Acoustic tools identify leak-generated noise, while correlators calculate leak positions based on signal timing. Tracer gas systems can detect escaping gas through pavement or soil. GPRS may also integrate GPS and GIS mapping to document findings with spatial accuracy, supporting long-term asset management and repair planning.

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How long it takes to find your leak depends on the system size, complexity, and access conditions. A standard survey of a small facility or municipal segment may take several hours, while larger networks can require multiple days. GPRS optimizes efficiency through pre-survey planning and site walks, real-time data collection, and advanced equipment, minimizing disruption and ensuring timely reporting.

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An annual leak survey is a scheduled inspection of water infrastructure to identify and document leaks. These surveys are critical for regulatory compliance, environmental protection, and cost control. Regular assessments reduce water loss, prevent hazardous conditions, and extend asset life. For municipalities and facilities, annual surveys support proactive maintenance and budget forecasting.

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Acoustic leak detectors help locate hidden water leaks by listening for the distinct sounds they produce, such as hissing or whooshing. Technicians use specialized equipment—including headphones, microphones, and listening sticks to detect these sounds above buried pipes. By analyzing sound intensity and patterns, they can pinpoint the exact location of a leak. However, not all leaks make detectable noise, especially when water pools around the site. That’s why it’s essential to rely on highly trained specialists, like GPRS water loss experts, who combine advanced technology with industry-leading expertise to find leaks, even when they’re silent.

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The most important advantage of acoustic leak detection is it’s a non-invasive technique, which means it eliminates the need to dig out the ground or remove any structures just to check the physical characteristics of the pipeline system. Potholing and other invasive techniques not only require tremendous effort but calls for repairs and replacements to be made afterwards. Trial and error method proves to be costly and time-consuming, where acoustic leak detection removes those unwanted hassles, and saves you time and money in the process. Other benefits of acoustic leak detectors include allowing homeowners and facility owners to have the problem fixed immediately, does not cause any damage to owner’s property, and acoustic listening devices are very accurate and precise.

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Video Pipe Inspection or VPI is a sewer inspection service using CCTV video cameras to mitigate or prevent infrastructure damage by inspecting underground water, sewer lines, and lateral pipelines. GPRS's NASSCO certified technicians can locate clogs, investigate cross bores, find structural faults and damages, and conduct lateral sewer line inspections.

3D laser scanners use LiDAR (light detection and ranging) to measure and record precise locations and distances, ultimately producing a point cloud file. The technology enables you to produce highly accurate digital measurements and images quickly and easily for use in construction and engineering projects. 3d laser scanning is a revolutionary tool to document existing conditions. It is invaluable in design, prefabrication, asset management, and facility modifications.