US DOT Class Location and HCA Studies
GDS provides image interpretation analysis services to produce GIS databases of structures for use in US DOT Class Location and HCA analysis. GDS interpreters have provided structure digitization services for over 100,000 miles of pipelines in the US. With this vast experience and a wealth of analysis of historical data, GDS provides very aggressive pricing per mile by analyzing the landscapes through which the pipeline right-of-way passes and the current population densities. The result of the survey is a GIS database of every structure that falls within the DOT regulated buffers that are attributed with a structure code which identifies its use. GDS uses numerous web-based databases to extract structure uses and business types and names which are captured in the GIS database.
GDS also provides a service to search for the most current digital, aerial imagery for studies if our clients do not have existing imagery. Upon completion of the study, all imagery and GIS databases are delivered to the client along with documentation suitable for inclusion in corporate Integrity Management Plans.
GDS’s methods for structure digitization have been evaluated by US DOT and have consistently been praised for their accuracy and completeness.
GDS also provides a service to search for the most current digital, aerial imagery for studies if our clients do not have existing imagery. Upon completion of the study, all imagery and GIS databases are delivered to the client along with documentation suitable for inclusion in corporate Integrity Management Plans.
GDS’s methods for structure digitization have been evaluated by US DOT and have consistently been praised for their accuracy and completeness.
DOT Classes shown in Green (Class 1), Yellow (Class2), and Red (Class3). US DOT buffers shown in Red
GDS clients are provided a White Paper defining the procedures used to develop the DOT classes. The White Paper is suitable for inclusion in the client's Integrity Management Plan (IMP).
The deliverables from both Class Location analysis and HCA analysis include: pipeline segments, digitized structures coded with structure code designating building use, buffers (300' and 660' for Class Location and CFER buffers for HCA analysis).
The deliverables from both Class Location analysis and HCA analysis include: pipeline segments, digitized structures coded with structure code designating building use, buffers (300' and 660' for Class Location and CFER buffers for HCA analysis).
High Consequence Area (HCA) Analysis
HCA analysis uses the same structure files as those used for Class Location analysis. The rule base for HCA analysis was developed from the guidelines established by US DOT PHMSA and produces a GIS data set that contains pipeline segments designated as HCAs and segments designated as non-HCA segments. Additionally, pipeline segment begins and ends are also computed as well as the cause of the HCA segment (Houses, Churches, Schools, Prisons, Outdoor Defined, etc.). All segments are fully georeferenced to the projection of the GIS data sets used for analysis.
HCA segments defined using CFER circle extents.
- GDS has conducted structure digitization projects whereby the client uses their own software for analysis while GDS supplies its expertise for image interpretation and digitization.
- GDS can provide aggressive pricing on Class Locaiton and HCA analysis where a previous study exists and the objective is to conduct an update.
Texas Railroad Commission (RRC) T4 Filings
Filing RRC T4 permits, whether new or amended, is a service GDS has performed for numerous pipeline clients. GDS can assist clients with T4 Filings by creating and submitting digital, GIS data sets and hardcopy maps.
Field Data Capture Forms
Intelligent Field Data Capture Forms are used to capture inventory and maintenance data that is formatted directly to the GIS database. Keyword and database attribute values are incorporated into all forms to enhance the speed of data capture as well as to assure data compatibility.
Database Development from Historical Cathodic Protection (CP) Readings
Historical analysis of Cathodic Protection readings is invaluable to the production of CP trends. Considerable CP data exists in hardcopy form and is not georeferenced to existing CP stations. Geoprocessing facilitates the development of historical CP data as time-stamped CP readings that are stored in GIS databases.