Tracking the Impact of Street Sweeping

How 2NFORM quantifies the water quality benefits of street sweeping

• Why Street Sweeping Matters
• What Inputs Are Needed
• How TELR Estimates Pollution Reduction
• How Results Are Displayed in 2NFORM
• Why It’s Useful

Why Street Sweeping Matters

Street sweeping is one of the most cost-effective non-structural best management practices (BMPs) available to stormwater programs. 2NFORM uses your sweeping program details and local rainfall patterns to quantify the pollutant reductions achieved, providing clear evidence of how day-to-day operations translate into measurable water quality benefits.

• Proven effectiveness. Modern sweepers remove large amounts of fine sediment and associated pollutants and trash before they can wash into storm drains making it a valuable pollutant source control strategy.
  
  
• High return on investment. Compared to the cost to design and construct structural BMPs, sweeping offers substantial pollutant reductions at lower cost.
  
  
• Scalable. Adjusting sweeping frequency, maximizing the curb access and targeting key routes can quickly increase pollutant load reductions.
  
  

What Inputs Are Needed

2NFORM’s Municipal Maintenance Module and O&M Calculator let you specify your current sweeping practices for each route:

• Route details (catchments or MS4-wide)
• Sweeper type (e.g., regenerative air, vacuum-assisted, mechanical broom)
• Frequency of sweeping
• Road type and traffic volume
• Curb accessibility to sweepers
• Pavement condition

See the Street Sweeping Starter Pack for more information on setting up your street sweeping data to allow 2NFORM to estimate the pollution reductions.

How TELR Estimates Pollution Reduction

TELR applies a two-part calculation:

1. Sweeping efficiency — how effective each pass is at picking up material. Factors include sweeper type, curb access, and pavement condition.
2. Material buildup — how much pollutant material accumulates between sweeping events. Factors include road type, sweeping frequency, and rainfall patterns.

By combining efficiency × buildup, TELR estimates how much material sweeping programs remove annually. These reductions are calculated on the 30m grid across your MS4 to reflect location-specific conditions.

How Results Are Displayed in 2NFORM

Results are reported as:

• Pollutant load reductions - tons/year of sediment and associated pollutants.
• Breakdown reductions by scale — gain insights on the annual pollutant reductions by route, catchment, or city-wide totals.
• Visual outputs — maps, charts, and tables that show where sweeping is making the biggest difference.
  
  

Why It’s Useful

• Optimize operations. Test how changes in sweeper type/frequency affect pollutant and trash reductions.
• Prioritize routes. Focus resources where buildup is greatest.
• Justify budgets. Demonstrate measurable water-quality improvements.
• Communicate impact. Translate O&M work into outcomes stakeholders understand.

Many TMDLs target particle-associated pollutants (sediment, metals, nutrients) and, increasingly, trash. Sweeping directly reduces these by removing debris and sediment before runoff transports them to outfalls. In 2NFORM, reductions are:

• Accounted against baseline to show progress toward WLAs,
• Reported by drainage and MS4-wide, supporting annual reports and audits, and
• Defensible, grounded in nationally validated science and local conditions.

If you have any additional questions or want to talk science with our team, please contact support and we will be happy to connect.