New Methods for Sewer Pipe Inspection- Pole Camera Screening to Reduce Costs For CCTV and Condition Assessment

PURPOSE AND BENEFITS OF PRESENTATION This presentation will show how use of a pole camera can reduce costs for sewer pipe inspection work. The presentation will show 3-5 completed case studies executing field inspection projects on storm, sanitary and combined sewers with great success throughout the country. INTRODUCTION The inspection of storm and sanitary sewer pipes have been in existence for decades. Newer cameras and now drones have improved the quality and details of information that can be provided during an inspection. However, not all pipes need to be fully inspected using traditional CCTV methods. Technology has provided high-definition pole cameras that can be used to inspect structures, screen pipes and identify which ones may not require full inspection providing a cost savings. Additionally, data provided by the pole camera can be used or condition assessment, connectivity between structures and show limits of cleaning. This presentation will show several case studies from Ohio and throughout the country. STRUCTURE INSPECTION AND PIPE SCREENING WITH POLE CAMERAS AECOM has been using pole cameras on projects throughout the country to provide structure and pipe inspections. The pole cameras were used to perform manhole condition assessments based on the National Association of Sewer Service Companies (NASSCO) approach. Inspectors to score each manhole from 1-5, with 5 being the worst. While in the manhole, inspectors performed NASSCO based condition assessments on the sewers, and assigned condition scores, 1-5. Manhole inspections used a collector program to capture existing construction materials, conditions, pipe measurements and inverts. The high quality of the digital cameras allowed inspectors to evaluate approximately 300 feet of each pipe (150 feet in the upstream manhole and 150 feet from the downstream manhole). In many cases, this was just enough information needed to use for condition assessment or recommend additional inspection. Prior to traditional CCTV inspection, pole camera inspections identified sewers with significant debris, severe structural damage, and other issues. Inspections were performed using handheld tablets and data captured included material of construction, condition, score/rating, and photographs. Data was uploaded immediately to the client's GIS database. All data was organized in the ESRI ArcGIS On-Line (AGOL) Collector program which allowed quality control from both the field and office. CCTV INSPECTION Engineers reviewed the pole camera inspections and recommended traditional CCTV inspections for pipes with a score of 4 or higher. Furthermore, the GIS based approach enabled engineers to determine if adjacent pipes should be considered in inspections, or for capital improvements that might include multiple segments or an entire street. Traditional CCTV work was conducted and inspections utilized NASSCO's Pipeline Assessment Certification Program (PACP) standards for pipe investigation. CONDITION ASSESSMENT For projects requiring condition assessments, assets with scores 3 and above received detailed evaluation and inclusion in a table summarizing the defects and determining the overall condition of the asset. Detailed condition assessments included the following: - Evaluation of three distinct condition scores, i.e. operations and maintenance (O&M); structural; combined. - Complete detailed review for structural grades 3-5 - Examination of surface issues - Determination of recommended rehabilitation CONCLUSION AND COST SAVINGS The use of a pole camera to perform condition assessments resulted in significant savings on inspection projects by several reasons: 1.Using the pole camera to perform both manhole and pipe inspections allowed for cost-effective identification of those assets that obviously needed investment and those that obviously didn't. Assets in those categories would not benefit from the more costly traditional CCTV investigation. 2.The program provided accurate condition information to contractors who were performing traditional CCTV work, identified segments that would need cleaning prior to inspection and the level of effort needed. 3.Pipe connectivity enabled engineers to verify existing sewer mapping or identification of errors and omissions in paper or GIS datasets. 4.The screening method was used on both storm and sanitary sewer systems with great success for condition assessment and providing data for modeling efforts. CASE STUDIES This presentation will showcase several projects where the pole camera was used to screen pipes, identify if cleaning was required or additional inspection. The projects shown are: City of Cleveland, OH Water Pollution Control- Inspection of over 18,000 manholes and 3 million linear feet of combined sewer pipes that were designated as being over 100 years in age. City of Overland Park, KS- Inspection of 15,000 linear feet of storm sewer that identified emergency sewer rehabilitation projects. City of Vermilion, OH- Sanitary sewer screening of over 900 manholes to reduce CCTV inspection costs. State of New Mexico Department of Transportation- Inspection of storm culverts throughout the state, including areas that had wildfire damage and soot/gravel blocking storm sewers. U.S. Army Garrison Kwajalein, Marshall Islands- Inspection of storm sewer pipes and culverts on the Kwajalein Atoll located in the South Pacific in which data was used for condition assessment and hydraulic modeling components.