Bentonville Sewer Collection Analysis and Peak Flow Management Program

Faced with a rapid rate of increased private development, the city of Bentonville selected a consultant team, which included TREKK, to build a hydraulic model of its sewer system and create a Capital Improvement Plan for four sanitary sewer basins. 

The project’s first phase included flow monitoring to determine existing flows within the four basins, including Inflow and Infiltration (I/I) and manhole inspection. We conducted flow monitoring on sewer trunk lines with diameters of 12 inches or larger and collected rainfall data to determine the baseline capacity of the basins. TREKK installed 27 flow monitors with visual data feeds and eight rain gauges to enhance model calibration and understanding of Rainfall Dependent Inflow and Infiltration. While monitoring and data collection was expected to take 12 months, the project objectives were achieved in only nine months.  

The team provided the city with a report detailing flow and hydraulic conditions; installation details; summary of service, maintenance and meter site performance; and hydrographs and scattergraphs, as well as updates to the sanitary sewer GIS database. 

The city then proceeded with Phase 2, which consisted of a sanitary sewer evaluation study of the city’s seven high-priority basins to prioritize assets for repair and/or replacement. TREKK provided field services, including the installation of six permanent flow meters, smoke testing, dyed water testing, additional manhole inspections using our TREKK360 camera, acoustic sounding and CCTV of approximately 10 percent of each basin. 

We then provided data analysis to identify I/I locations, quantify and assign I/I to the pipe and manhole defects, assign preliminary costs for repairs, and prioritize assets for rehabilitation or replacement based on cost/gallons-per-day of I/I removed.