Using GIS to support natural gas leak detection
Brett Johnson, Dan Heselton, Nancy Pehrson
Reliant Energy Minnegasco
700 West Linden Avenue
Minneapolis, MN 55403
Introduction
Reliant Energy Minnegasco is a natural gas utility serving over 685,000 customers in
over 240 communities in Minnesota. REM, like other gas utilities, incurs significant
costs in surveying its distribution system for leaks and maintaining leak records.
Technicians conduct leak surveys by driving leak-detection-equipped vehicles over
underground gas lines. Paper documents are used to track and maintain 19 types of
surveys that can be performed on over 800 leak survey areas. Thousands of different
survey records are produced.
In 1997 REM was involved in the testing of a new leak-sensing technology. During this
effort, automation of REM's leak detection system was identified as an area that could
provide cost savings and other benefits and eliminate the intensive manual effort involved
in the leak detection survey process. Early in the analysis phase, it was determined that
the Automated Leak Detection System (ALDS): (1) needed to work with multiple leak
detection technologies and (2) provide technicians with the capability of downloading on
demand digital map data exported from the company GIS for scheduled or uniquely
defined surveys.
Our vision of the ALDS was to enable leak detection technicians to utilize GIS on a daily
basis in their mobile survey work. The system would provide each technician with a list
of scheduled surveys that added route tracking, leak location and completion date data as
the survey work was executed. At day's end, data would be uploaded and imported into
the company GIS. When a leak was encountered, the technician would be able to enter
leak report information on a computer screen. Leak data would be uploaded to a
construction work management mainframe system application. The ALDS would
completely eliminate the paper map and leak report process in place at the time.
We designed the ALDS vehicle systems to include on-board computers, GPS, and dead
reckoning hardware integrated with leak-detection equipment. Xplore's GeneSys P133
hardened tablet PC was selected for this vehicle application. The computer's design met
the functional requirements for the application and the screen visibility was evaluated as
best for outdoor/vehicle use.
We selected a vendor to customize a vehicle-mapping software package, write interfaces
to the leak detection equipment and provide GPS and dead reckoning hardware required
to obtain system accuracy.
Software designed for the ALDS needed to interface with existing REM legacy systems
and the vehicle mapping software while being user-friendly for field applications.
Integration of the various systems needed to provide users with an application that
appeared to be a single, easy-to-use system. Acceptance of the ALDS system was key to
seeing efficiency and productivity results.
