Bradley International Airport Sewer Study

windsor locks, RI

AI provided an in-depth sewer study at Bradley International Airport. The airport’s sanitary sewer system is comprised of approximately 78,000 lf. of sewer lines, 250 sewer manhole structures, and four pump stations that collect convey and pump the site waste to the Metropolitan District Commission's (MDC) larger collection system. The sewer study consists of several components, including field survey, field inspections of the sewer infrastructure, flow monitoring and computer modeling of the system, reporting on findings and recommendations, and a multi-year capital improvement plan. AI is providing surveying services to locate all manholes and pump station structures, and is referencing the survey to the Connecticut State Plane Coordinates System and the NAVD88 vertical datum. The survey is being done to update incomplete and/or incorrect mapping of the site system. The locations of the system structures are being done with Real Time Kinematic (RTK) GP, which is connected to a statewide survey network via cellular phone system. AI personnel are also providing field inspections of the system structures and sewer lines.

AI has retained a video inspection company to inspect all 78,000 lf. of sewer line. AI is coordinating and observing the video inspections, and will also inspect the 250 manhole structures and four pump stations at the airport. Flows in the system will be monitored over a four-week period to establish base flows in the system, and to record spikes if pipe flow due to inflow and/or infiltration. The flow, survey, and inspection data will be compiled to build a hydraulic model of the sewer system in Autodesk Storm and Sanitary Analysis. Once built, the collected flow data will be used to calibrate the hydraulic model, and infiltration/inflow will also be modeled based on a selected design storm. After the survey, inspection, and modeling tasks are completed, AI will prepare a comprehensive sewer study report detailing the findings of the study, and make recommendations for improvements. System improvements will include options for repair, replacement, and rehabilitation of system components to help reduce inflow and infiltration into the system, reestablish system integrity, and plan for long term maintenance of the system. The report will also include cost estimates for the proposed improvements. Those estimates will be the basis for the final portion of the project, which is a five-year capital improvement plan. The cost of system improvements will be forecasted over the five-year period, based on projected available funding, with all figures for future years tied to an average Consumer Price Index (CPI) over the last five years.


  • Duration: 2013 - 2016
  • Project Scope:
    • Topographic survey
    • Construction survey
    • Bathymetric survey