Street Sweeping Program

Overview 🌊

The City of Sammamish’s Street Sweeping Program helps protect water quality, reduce urban flooding, and maintain the integrity of our stormwater infrastructure. Street sweeping is a key requirement under the NPDES Phase II Municipal Stormwater Permit and is included in the City’s annually updated Stormwater Management Program Plan.

By regularly removing leaves, sediment, and debris from streets, the program prevents pollutants from washing into storm drains and local waterways—supporting both public safety and environmental health.

View the Current Street Sweeping Schedule here.

Current Operations 🚛

• Coverage: ~60 miles of arterial roadways and ~220 miles of local access roads.

• Priority Areas: Arterials are swept more often due to higher traffic and pollutant levels; neighborhood streets are swept less frequently due to lower traffic and physical obstructions such as parked cars and vegetation.

• Seasonal Schedule: More frequent sweeping in fall and winter to manage leaf drop and storm debris.

• Equipment: Rear broom and air vacuum sweepers. Collected material is taken to a designated yard before disposal at a landfill.

• Monitoring: Pollutant load reductions (e.g., phosphorus, nitrogen) are estimated using established calculation tools.

Department of Ecology Grant & New Sweeper 💰

In 2023, the City was awarded a Stormwater Financial Assistance Program (SFAP) grant to support the purchase of a high-efficiency regenerative air sweeper.

• Grant Number: WQC-2023-Sammam-00171

• Award: $276,195 (75% of eligible costs)

• City Match: ~$92,065 (25% of eligible costs)

• Equipment: Tymco Model 600 regenerative air sweeper — highly effective at removing fine particles and pollutants before they enter stormwater systems.

• Total Cost: $360,000–$400,000 (depending on chassis)

Benefits of the New Sweeper 🌟

• Enhanced Cleaning Power: More efficient pollutant removal, helping protect streams, lakes, and salmon habitat.

• Faster Spill Response: Owning a sweeper allows the City to respond quickly to emergency spills and resident requests.

• More Frequent Sweeping: Increased coverage of arterials and neighborhood streets.

• Cost Savings: Reduced reliance on contracted services and better control over scheduling.

• Measurable Impact: Ability to track volume and type of debris collected for water quality benefit reporting.

Future Program Enhancements 🚦

The City’s Enhanced Maintenance Plan will expand sweeping efforts in:

• High-traffic corridors

• Leaf-heavy canopy areas

• Industrial and high-pollution zones

This proactive approach will help:

• Meet and exceed NPDES permit requirements

• Protect water quality and wildlife habitat

• Improve the cleanliness and appearance of City streets