It’s All About the Data
June 29, 2011After the CCTV inspection on the pipe, lateral or manhole is completed, what happens to the movie and collected condition information?
It used to sit in boxes or shelves in a closet somewhere. Even with the advent of computers. it often never made it from the truck to the office. Now everyone realizes that survey data is too valuable not to share it between departments. And the NASSCO coding standard makes it easier than ever to share that data with other software programs.
Some utilities still store the survey data on DVDs or removable hard drives, but most are backing this data up to their servers so that all departments will have access to the information. The movie is usually stored in one location and shared between GIS and IMS programs with each of them storing the location and file name so it can be accessed and viewed. With a published list of codes and a data dictionary outlining field requirements, the NASSCO transfer file can be easily imported into a variety of other software programs.
Most have added a standard import process for bringing the survey data into their management software so that costs can be easily tracked and additional work orders created for repair work or other scheduled maintenance. The survey data can also be shared between data collection software products since import/export functions are required for PACP/LACP/MACP certification by NASSCO.
Many of the data collection software vendors have incorporated an interface with GIS to access survey detail within the GIS program by the engineering staff in the office. The user can select the pipe on the map and link to the movie to open it for playback.
Some interfaces include the survey history of the pipe allowing the user to track the conditions and their changes over time. Usually the collection database can be “searched” and pipes highlighted in the GIS program that contain specific conditions or pipe grades making it much easier to plan additional work like repairs or jetting.
Many engineering firms have built analysis modules to search these databases and make recommendations based on built-in risk assessments. It is not enough to know there is a fracture or a hole in the pipe, it is also important to consider the risk of failure of that particular pipe. Factors like public impact, environmental impact, age and cost of repair versus replacement are all considered and built into their analysis. This makes it more important that the collected data is consistent. Since a fracture in a pipe will have more serious consequences than a crack it is important that the inspector has identified the condition correctly.
“The use of standardized programs, like NASSCO-PACP, can significantly assist with the consistency of data collection. In addition, every SOP should include a defined process for quality assurance/quality control (QA/QC) process, ” said Mike Fisher, Water Works Engineers, Roseville, Calif.
When NASSCO introduced the PACP standard in 2002, training the inspector to understand the different conditions was a major component of the program. NASSCO is currently working on a Re-Certification program that each inspector will take every three years to bring them up to date on the new codes added for different survey types like grouting and storm inspections, as well how to handle new technology like scanning cameras and laser inspections.
It is also important that a quality control program is in place to verify that the data is accurate. This is as simple as determining a percentage of inspections to review for an inspector. A list of random numbers is created and used to pick surveys for review. An accuracy score is then created for the inspector and will identify inspectors that may need more assistance in understanding the coding requirements. An effective method of quality control is found on the NASSCO.org website.
With the newer collection technologies, more accurate measurements are now possible. The scanning camera systems allow the engineer in the office to use their mouse as the tractor as they look through the pipe and pan and tilt to view conditions. The pipe is shown in the normal view or as a “flat” pipe.
Measurements can be taken for conditions like tap size or crack width. These camera systems are even changing the way the pipes are assessed, with the visual collected in the field and the engineering staff doing the condition assessment later in the office instead of on the truck. Laser systems used on the cameras allow the inspector to measure the distance between the two points of light in the picture and then with this known reference distance, cracks or laterals can be measured. The NASSCO measurement fields have been modified to accept measurements accurate to three decimal places.
The data is also used by the GIS departments to verify that the map data is correct. Many maps have been created from old, historic mapping data and may not relate to actual in ground conditions. GPS coordinates can be collected in the field during an inspection and saved in the NASSCO inspection format. Other asset detail like location, diameter, material, lining, and pipe lengths are also collected. This information can be exported so the GIS department can update their maps. Buried manholes that are found are added to the map creating new assets, both manhole and pipes.
A large metropolitan sewer district in Kentucky has been using this method to review about 3 million lf of inspection data provided by both contractors and their own sewer crews. District officials select the random number from the survey list using the NASSCO field “sheet.” A copy of the movie and survey report is sent to a QA/QC team to review for accuracy. Once the surveys have been accepted they are then imported into the Infor Hansen program and used for creating follow-on work orders for immediate repairs and scheduling of preventative maintenance activities. The use of a NASSCO certified software collection program, Pipelogix, improved the sewer crews scores by requiring entries that had been missed using the old field collection program. Their scores went from an accuracy range around 60 to 95 percent because of the built-in fail safes, which assist the operators in correct coding methods.
Joan Stone is president of Pipelogix Inc. and NASSCO Software Vendor Committee Chair.