Innovations in SUI (Subsurface Utility Information), SUM (Subsurface Utility Mapping) and SUE (Subsurface Utility Engineering) are growing every year, These innovations can cost a lot but can have significant reduction is risk and costs associated with utility service locating, mapping and construction projects.
We are going to share some of the latest utility locating technologies that have proven to be useful and accurate.
In Australia, after analyzing the Sydney Light Rail project, ACIL Allen Consulting stated that if error-free 3-D subsurface utility maps were provided in the planning and design stage, the project’s completion could have been preponed by 1.5 years, with lesser cost and reduced amount of risk.
ACIL Allen Consulting
Subsurface Utility Infrastructure: Increasing Costs
Development in subsurface utility infrastructure is crucial for any city to work efficiently. The U.S. has a total of around 35 million miles of underground pipelines and utilities, and a major chunk of this infrastructure is over sixty years old. In particular, the water pipelines have been in-place for more than ten decades. In this context, as per Common Ground Alliance, the country witnessed 316,422 subsurface infrastructure incidents in the year 2017.
The direct expenditure associated with such strikes was approximately $4021 (USD).
As per University of Birmingham research (What Do Utility Strikes Really Cost, 2016), on cumulative indirect and social expenditure caused due to a utility strike, the total expenditure was found to be twenty-nine times of the direct expenditure per strike.
So, What are some of the latest SUI Innovations in Technology?
The government and the AEC industry stakeholders do understand the importance to invest in SUM technologies especially in developed economies and to felicitate their requirements, a number of private companies offer innovative hardware, software, and services solutions.
The following are some key technology innovations in the subsurface utility infrastructure industry:
Integration of RTK GNSS with EM wand and digital capturing has been a key development in order to accurately detect, locate and hold a digital record of the locate. One example is of Terraflow Geomatics Utility Mapper which has contributed significantly in enabling digital capture of the location of subsurface pipes and in integrating the output of CAD and GIS for efficient user accessibility.
Use of LiDAR technology and camera to get the as built X, Y and Z coordinates of a new pipeline (Truck mounted LiDAR and camera). This technology has been developed by Lux Modus (Headquartered in Canada).
Combination of LiDAR and GPR; GPR to map the subsurface infrastructure and LiDAR to map the above surface infrastructure. DGT Associates partnered with Siteco Informatica Srl and Sensors & Software Inc, to develop this technology to map surface and subsurface infrastructure simultaneously.
Simplified interpretation of GPR data: The technology is capable of combining scans and creating a tomographic display, making it easier for all stakeholders to interpret and not just geotechnical experts. Leica Geosystems is a leading provider of such solutions.
Statistical averaging to improve GPR’s depth penetration: It is through stacking, that the signal to noise ratio is increased. pulseEKKO® GPR system developed by Sensors and Software, Inc works on this principle.
Truck mounted GPR systems with speed up to 130 Km/h. A number of companies including IDS GeoRadar (Subsidiary of Hexagon AB), ImpulseRadar and Earth Radar (A VAC Group Company) have developed such products.
Inertial mapping is used to map pipeline networks of distances up to 2 km of length. The orientation measurement unit (OMU) contains inertial sensors & on-board memory enabling a possibility to have 15 cm precision. The data produced can be integrated on platforms such as AutoCAD.
Acoustic surveying: These devices use audible sound waves to map underground utilities and can operate to a depth of 30 ft. The process is not affected by soil type or moisture content.
Augmented reality viewing of underground infrastructure: Companies including vGIS and AVUS offers such technology. The use of AR is helpful in validating the accuracy of the SUM operation and to give a better look & feel of the utilities and pipelines installed in the subsurface to various stakeholders.
A number of studies have been done to analyze the cost benefits of investing in SUM. For instance, as per the research conducted by Pennsylvania Dept. of transportation in 2012, ratio of expenditure on SUM to saving on entire Highway project was 1: 11.39, i.e. for every dollar spent on SUM, the entire project saved 11.39 USD while the SUM accounted for 1.65% of the entire project cost. The scope of this study includes evaluation of twenty-two SUE and eight non-SUE highway projects.
It was found that the maximum cost saving was in project relocation cost as SUM data at earlier stage led to better designing of highways. SUM data not only enabled efficient designing, it also led to reduced time wastage caused by unnecessary construction.
In Australia, after analyzing the Sydney Light Rail project, ACIL Allen Consulting stated that if error-free 3-D subsurface utility maps were provided in the planning and design stage, the project’s completion could have been preponed by 1.5 years, with lesser cost and reduced amount of risk. Although the project was finished as per the signed contract, but it was only because risk of delays and additional costs caused because of unidentified underground utilities was already included in the project scope.
In conclusion, innovations in technology to map the existing and the new subsurface utility infrastructure is going to be of crucial importance to reduce the number of utility strikes that take place on a daily basis. Such strikes not only hurt monetarily, but also cause loss of human lives. The reason behind investing in subsurface utility mapping doesn’t just restrain to reducing the incidents today but is also to be future ready. The world is progressing towards developing digital cities and for them to work efficiently, accurate underground utility maps are a must.