Street Sweeping Manual
1-1
Chapter 1. Manual Introduction
1.1
Introduction
Street sweeping implemented by municipalities across the state of Washington aims to reduce
the impacts of pollutants deposited on roadways due to traffic, roadway maintenance activities,
construction, littering landscaping, trees, and runoff from adjacent land uses. The U.S.
Environmental Protection Agency (EPA) considers street sweeping a stormwater pollution
prevention best management practice (BMP) under its National Pollutant Discharge Elimination
System (NPDES) Permit program [1]. Growing concerns over stormwater pollution impacts on the
environment drive regulatory agencies to include more stringent requirements for municipality-
driven, source-reduction activities. The Washington State Department of Ecology (Ecology)
reissued the Phase I, Western Washington (WWA) Phase II, and Eastern Washington (EWA) Phase II
Municipal Stormwater General Permits for discharges from Municipal Separate Storm Sewer
Systems (MS4 Permits) for the 2024–2029 Permit cycle effective August 1, 2024. The three 2024–
2029 MS4 Permits require Permittees to develop and implement a street sweeping program.
Although many jurisdictions currently run street sweeping operations, those that do not may face
challenges initiating a municipal street sweeping program. Additionally, existing programs may
need program modifications to meet the 2024–2029 MS4 Permit requirements, or Permittees may
desire to expand or improve their existing programs. This manual serves as an informational
resource to guide municipalities in establishing, implementing, and improving effective street
sweeping programs in compliance with the regulatory requirements of the 2024–2029 MS4 Permit
cycle in both eastern and western Washington.
1.2
Manual Background and Purpose
Currently, there is no comprehensive information or practice guide on the topic of street sweeping
directed toward municipalities in the state of Washington. While considerable research on street
sweeping exists, this project aims to compile the breadth of knowledge to specifically support
compliance with the MS4 Permit’s street sweeping requirements, as well as additional
considerations to develop and enhance street sweeping programs. Permittees statewide requested
additional guidance to support compliance with the 2024–2029 MS4 Permits. In response, the
Washington Stormwater Center (WSC) – Washington State University (WSU), in partnership with
Evergreen StormH2O, submitted a Stormwater Action Monitoring (SAM) Round 4 proposal to
develop a guidance manual, aimed at providing Permittees with information and tools to develop
and improve street sweeping programs that comply with the 2024–2029 MS4 Permits. Ecology
decided to remove the proposal from the submission list and fund the project using funds from
the Washington State 6PPD Proviso.
This manual builds on a literature review and policy discussions initiated by the Street Sweeping
Technical Sub-Group, a sub-group of the Puget Sound Ecosystem Monitoring Program’s
Effectiveness Evaluation Team. It was further developed using information collected by an
expanded literature search of journal articles and municipal documents, interviews with Permittees
Chapter 1
Manual Introduction
Street Sweeping Manual
1-2
statewide, and guidance from a technical advisory committee (TAC). The intended audience
includes municipal staff involved with the development, management, and implementation
of street sweeping programs.
1.3
MS4 Permit Requirements
The MS4 Permits, effective August 1, 2024, require Permittees to develop and implement a
municipal street sweeping program no later than July 1, 2027. Street sweeping requirements are
provided in Section S5.C.10.f of the Phase I MS4 Permit, Section S5.C.9.e of the WWA Phase II MS4
Permit, and Section S5.B.6.b of the EWA Phase II MS4 Permit [2, 3, 4]. The following sections
provide an overview of the street sweeping requirements and highlight the differences between the
Phase I and Phase II MS4 Permit. Appendix 1-A provides a comparison of the Phase I and Phase II
street sweeping requirements.
Note: MS4 Permit language included in this document provides the reader with context for the
purpose of this manual’s development. Slight variations in street sweeping requirements exist
between the 2024–2029 MS4 Phase I and Phase II Permits. Since Permit language can change with
future Permit reissuances, refer to the current version of the MS4 Permit that applies to your
jurisdiction. The 2024–2029 MS4 Permits require inclusion of the elements described in this section.
1.3.1 Priority Areas
All Permittees must apply their street sweeping program to curbed municipal streets in the MS4
drainage area that discharge to outfalls and meet any of the following criteria:
High-traffic streets, such as arterials or collectors
Streets that serve commercial or industrial land use areas
Chapter 3 provides more detail on selecting priority areas for street sweeping and Chapter 5
describes methods for designing street sweeping routes.
Note that the Phase I MS4 Permit refers to “high priority areas” and the Phase II MS4 Permits refer
to “priority areas.” “Priority areas” is used throughout this document and is intended to also mean
“high priority areas.”
1.3.2 Program Timing
All Permittees must sweep priority areas at least once between the months of July and September.
Phase I Permittees must also sweep at least three additional times per year (as they determine) to
provide additional water quality benefits, while Phase II Permittees must only sweep at least two
additional times per year. However, for the 2027 calendar year, the MS4 Permits only require one
sweeping event between July and December.
To achieve compliance, Permittees must document that sweeping occurred in at least 90 percent
of their identified priority areas for each sweeping event.
Based on actual maintenance experience, Permittees may document the reasoning for an
alternative sweeping timing and frequency based on local conditions and estimated pollutant
deposition quantities. Note that the Permits do not explicitly state that the existence of such
Chapter 1
Manual Introduction
Street Sweeping Manual
1-3
documentation, which must be certified in accordance with G19 – Certification of Signature, allows
the Permittee to adopt this alternative sweeping program schedule (unlike the existence of G19-
certified documentation to justify adopting an alternative inspection schedule for catch basins and
stormwater facilities). However, per conversations with Ecology representatives, Ecology confirmed
that the intent of this permit language is to provide Permittees with an option for implementing an
alternative sweeping schedule.
1.3.3 Operational Procedures
Permittees must properly operate and maintain street sweeping equipment in adherence to
the equipment’s design performance specifications. Chapter 4 provides further guidance on
equipment operation and maintenance.
1.3.4 Street Waste Disposal
All Permittees must dispose of sweeper waste material in accordance with Appendix 6 – Street
Waste Disposal of the Phase I and Phase II MS4 Permits. Appendix 6 includes general procedures
for handling street waste liquids and solids. Chapter 7 provides more detail on street waste
disposal.
1.3.5 Reporting
All Permittees must document and submit the following information for the sweeping program’s
priority areas with the Annual Report by March 31, 2028:
A map identifying areas swept
Sweeping dates
Sweeping frequency
Type of sweeper
Total curb miles of priority areas and curb miles swept
Approximation of street waste solids removed for each sweeping event
Chapter 6 provides guidance on establishing compliant documentation and reporting protocols.
1.3.6 Training
Permittees must train all staff involved in operations and maintenance, including street sweeping.
The training shall address the importance of protecting water quality; operations and maintenance;
performing job activities to prevent or minimize water quality impacts; and procedures for reporting
water quality concerns. Permittees must provide follow-up training to address changes in
procedures, techniques, requirements, and/or staffing. Required documentation includes
maintaining records of training dates, course descriptions, and names and positions of attending
staff. Chapter 4 provides additional guidance on street sweeping training.
1.4
Manual Organization
This manual consists of eight chapters, each covering different topics for ease of use. The following
describes each chapter’s purpose:
Chapter 1
Manual Introduction
Street Sweeping Manual
1-4
Chapter 1 – Manual Introduction
o Introduces the manual’s background and purpose, as well as describes the
intended audience, relevant MS4 Permit requirements, and manual organization.
The chapter’s appendix includes a comparison table of the Phase I and Phase II MS4
Permit requirements.
Chapter 2 – Street Sweeping Benefits
o Summarizes the impacts street waste can have on water quality and the benefits
street sweeping can provide to reduce those impacts. This chapter also describes
ancillary benefits of street sweeping, such as benefits to public health and safety.
Chapter 3 – Identifying Priority Street Sweeping Areas
o Provides guidance to assist Permittees in identifying specific priority areas for their
street sweeping program using information from Chapter 2 and available
jurisdictional information.
Chapter 4 – Establishing Street Sweeping Programs
o Provides guidance for developing new street sweeping programs, including
introducing street sweeping program elements, defining program goals, selecting
equipment, and other program considerations. This chapter also provides guidance
on establishing and organizing multi-department collaborations to support street
sweeping programs. The chapter’s appendices include example contracts for hiring
out street sweeping services and street sweeping interlocal agreements.
Chapter 5 – Optimizing Street Sweeping Practices
o Provides guidance for improving street sweeping programs such as designing
sweeping routes, improving efficiency and efficacy of existing programs, and
identifying variables that may influence efficiency and efficacy. This chapter also
includes guidance for measuring performance for street sweeping activities.
Chapter 6 – Documenting, Tracking, and Collecting Data for Street Sweeping Activities
o Provides guidance for documenting, tracking, and collecting data for street
sweeping activities to assist Permittees with MS4 Permit compliance, tracking
program costs, and improving program activities. The chapter’s appendices include
a manual tracking template and example tracking and reporting documentation.
Chapter 7 – Disposing of Street Sweeping Waste
o Summarizes options for disposing of street sweeping waste, both liquids and solids.
This chapter also describes estimating the quantity and size of decant facilities
needed for disposal and planning the design, construction, and operation of a
decant facility. The chapter’s appendices include spreadsheet tools for estimating
generated waste and sizing decant facilities.
Chapter 8 – Street Sweeping Cost Considerations
o Provides guidance on estimating costs involved with creating or improving a
municipal street sweeping program, including how to collect or use jurisdictional
data for lifecycle cost evaluation and growth projections. This chapter also
describes potential funding sources. The chapter’s appendix includes a tool
for Permittees to estimate program costs.
Chapter 1
Manual Introduction
Street Sweeping Manual
1-5
1.5
References
[1] U.S. EPA Office of Water, "Stormwater Best Management Practice: Parking Lot and Street
Sweeping," 13 December 2023. [Online]. Available: https://www.epa.gov/npdes/national-
menu-best-management-practices-bmps-stormwater-pollution-prevention-and-good.
[2] Washington State Department of Ecology, "Eastern Washington Phase II Municipal Stormwater
Permit," Washington State Department of Ecology, Olympia, 2024a.
[3] Washington State Department of Ecology, "Western Washington Phase II Municipal Stormwater
Permit," Washington State Department of Ecology, Olympia, 2024b.
[4] Washington State Department of Ecology, "Phase I Municipal Stormwater Permit," Washington
State Department of Ecology, Olympia, 2024c.
Street Sweeping Manual
1-6
Appendix 1-A
Permit Section
Eastern WA Phase II
Western WA Phase II
Phase I
EWA: S5.B.6.b
WWA: S5.C.9.e
Phase I: S5.C.10.f
No later than July 1, 2027, develop and implement a municipal
street sweeping program to focus on priority areas and times
during the year that would reasonably be expected to result in
the maximum water quality benefits to receiving waters. The
following program elements shall be included:
No later than July 1, 2027, develop and implement a municipal
street sweeping program to focus on priority areas and times
during the year that would reasonably be expected to result in
the maximum water quality benefits to receiving waters. The
following program elements shall be included:
No later than July 1, 2027, develop and implement a municipal
street sweeping program to focus on priority areas and times
during the year that would reasonably be expected to result in
the maximum water quality benefits to receiving waters. The
following program elements shall be included:
EWA: S5.B.6.b.i
WWA: S5.C.9.e.i.
Phase I: S5.C.10.f.i
Priority Areas: Apply street sweeping program to curbed
municipal streets that discharge to outfalls and meet any of the
following criteria:
(a) High traffic streets, such as arterials or collectors.
(b) Streets that serve commercial or industrial land use areas.
Priority Areas: Apply street sweeping program to curbed
municipal streets that discharge to outfalls and meet any of the
following criteria:
(a) High traffic streets, such as arterials or collectors.
(b) Streets that serve commercial or industrial land use areas.
Priority areas: Apply street sweeping program to curbed
municipal streets in MS4 drainage areas that discharge to
outfalls and meet any of the following criteria:
(a.) High traffic streets, such as arterials or collectors.
(b.) Streets that serve commercial or industrial land use areas.
EWA: S5.B.6.b.ii
WWA: S5.C.9.e.ii
Phase I: S5.C.10.f.ii
Program timing: Sweep priority areas at least once between July
and September each year and at least two additional times a
year as determined by the Permittee to provide additional water
quality benefits. For calendar year 2027, only one sweeping
event is required between July and December.
(a) Compliance during this Permit term shall be determined by
records of a sweeping program designed to sweep all priority
areas identified and sweeping at least 90% of priority areas each
sweeping event.
(b) Permittee may document reasoning for alternative sweeping
timing and frequency based on local conditions (e.g., climate)
and estimated pollutant deposition quantities.…