To identify system deficiencies related to inflow and infiltration (I/I) issues throughout several neighborhoods, Liberty Utilities (Liberty) engaged B&N in conducting smoke testing in eight different developments within Smith County, Texas. B&N worked closely with Liberty to help identify I/I issues and build their system map for additional value.
Enhancing the System
Within the eight communities, the team encountered challenges locating existing records and accurate geographic information system (GIS) mapping. Only static PDF maps with rough estimates of linear footage and asset locations were available, requiring detailed field investigations to verify asset locations. A system that was initially estimated to contain 55,000 linear feet (LF) of sanitary sewer mains was nearly doubled by project close.
Using the updates to the existing information, B&N staff designed a simple GIS map as a repository for collected GPS coordinates and a Microsoft Access database to store located asset attributes.
Additionally, B&N:
- Used GPS units in the field to record locations and verify the location of 57 manholes and 40 private and public cleanout
- Smoke tested and gathered asset attributes to a total of 109,173 LF of sanitary sewer mains and its fixtures, nearly doubling from the estimated 55,000 LF
- Identified 99 system deficiencies contributing to I/I
The team worked with the available PDF maps and prepared a simple GIS map for location overview. B&N also successfully adjusted resources to changing factors, such as linear footage increases and coming across unexpected lift stations. This helped to regulate progress and performance and ensure progress towards still timely completion. A final report was made available to Liberty along with GIS files and a Microsoft database to view, update or add to the current data.
Ongoing Benefits
The information collected and presented by B&N can now be used towards system mapping and planning for future operations and maintenance programs. As a result, B&N has been approached for additional I/I field services and assistance with Liberty’s Capacity, Management, Operations & Maintenance (CMOM) program.