NV5 developed the Municipal Separate Storm Sewer System (MS4) Flow SystemTM to specifically help municipalities identify, assess, and eliminate non-stormwater flows in their storm drains. The web-enabled flow data system relies on ultra-sonic sensors, wireless data loggers, and a customizable web portal. The near real-time data is sent to a customizable web portal, where it is organized and displayed to create a hub of data interaction, interpretation, and collaboration among those involved in the project.
As part of an on-going project, NV5 has been deploying this flow data system in more than 100 deployments since 2016 throughout the City of San Diego’s MS4 network to collect accurate measurements of real-time flow rates and trends to establish baseline flow conditions, measure the effectiveness of strategies implemented toward reducing or eliminating dry weather flows and estimate pollutant load reductions. The City continued to expand the project and deploys meters at nearly all 30 of the highest-priority major MS4 outfalls twice each year. Project staff are provided access to near real-time flow conditions via the web portal to evaluate flow patterns utilizing site-specific graphs and reports of the daily, weekly, and monthly flow patterns. The City’s staff use the data and statistics to determine when significant flows were occurring and to schedule dry weather flow observations for a higher probability of success at finding a meaningful source of the flow pattern. Once sites were sufficiently characterized or flows were eliminated, the equipment was easily removed and installed in a new location, providing scalability and coverage with relatively fewer instruments.
