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Document Author: Ecology

2019 – 2024 Ecology WW Phase II Municipal Stormwater Permit

Summary: External link to Ecology Phase II permit site

We develop and administer Clean Water Act National Pollutant Discharge Elimination System (NPDES) municipal stormwater permits in Washington. The Western Washington Phase II permit requires local governments to manage and control stormwater runoff so that it does not pollute downstream waters.
The current permit is effective Aug. 1, 2024, and expires on July 31, 2029.
Overview of permit timelines
View
permit timelines
for continuing permittees. These timelines provide an overview of major deadlines for implementing permit requirements.
Annual reports for the calendar year are due by
March 31 the following year.
Municipal stormwater permit guidance
For guidance about applying, changing, or implementing and complying with your municipal stormwater permit see
municipal stormwater guidance
Stormwater manuals
provide stormwater permit implementation and management guidance. For more general stormwater permit guidance, see the
stormwater guidance
page.
Frequently asked questions
Have a question? Check out our
frequently asked questions page
Permit history
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to receive updates about this permit.

Street Sweeping Program Guidance Manual Final Manual Outline

Summary: street sweeping manual final outline

Street Sweeping Manual
Detailed Manual Outline
July 2024
Street Sweeping Manual | Detailed Manual Outline
Table of Contents
Table of Contents …………………………………………………………………………………………………………………………. i
Chapter 1.
MANUAL INTRODUCTION …………………………………………………………………………………………. 1
1.1
Introduc#on ………………………………………………………………………………………………………………… 1
1.2
Manual Background and Purpose ………………………………………………………………………………….. 1
1.3
MS4 Permit Requirements …………………………………………………………………………………………….. 1
1.4
Manual Organiza#on ……………………………………………………………………………………………………. 1
Chapter 2.
STREET SWEEPING BENEFITS……………………………………………………………………………………… 2
2.1
Chapter Introduc#on ……………………………………………………………………………………………………. 2
2.2
Literature Synthesis ……………………………………………………………………………………………………… 2
2.2.1
Sources of Street Waste ……………………………………………………………………………………………. 2
2.2.2
Physiochemical Characteris#cs ………………………………………………………………………………….. 2
2.2.3
Removal Efficiency ……………………………………………………………………………………………………. 2
2.2.4
Street Pollutant Transport …………………………………………………………………………………………. 2
2.2.5
Water Quality Benefits ……………………………………………………………………………………………… 2
2.3
Co-Benefits …………………………………………………………………………………………………………………. 2
Chapter 3.
IDENTIFYING PRIORITY STREET SWEEPING AREAS ………………………………………………………… 5
3.1
Chapter Introduc#on ……………………………………………………………………………………………………. 5
3.2
Literature Synthesis ……………………………………………………………………………………………………… 5
3.3
Applicable Permit Requirements ……………………………………………………………………………………. 5
3.4
Iden#fying and Selec#ng Priority Street Sweeping Areas ………………………………………………….. 5
3.4.1
Using Collected Data to Iden#fy Priority Street Sweeping Areas …………………………………….. 5
3.4.2
Using Literature Findings to Iden#fy Priority Street Sweeping Areas ………………………………. 5
3.5
Other Jurisdic#onal Priority Areas for Street Sweeping …………………………………………………….. 5
Chapter 4.
ESTABLISHING STREET SWEEPING PROGRAMS …………………………………………………………….. 7
4.1
Chapter Introduc#on ……………………………………………………………………………………………………. 7
4.2
Street Sweeping Overview …………………………………………………………………………………………….. 7
4.3
Program Elements ……………………………………………………………………………………………………….. 7
4.3.1
Administra#on …………………………………………………………………………………………………………. 7
4.3.2
Staffing……………………………………………………………………………………………………………………. 7
4.3.3
Scheduling ………………………………………………………………………………………………………………. 7
4.3.4
Opera#ons and Maintenance …………………………………………………………………………………….. 7
Table of Contents
Street Sweeping Manual | Detailed Manual Outline
4.3.5
Street Waste Disposal ………………………………………………………………………………………………. 7
4.3.6
Documenta#on & Repor#ng ……………………………………………………………………………………… 7
4.3.7
Training …………………………………………………………………………………………………………………… 7
4.4
Program Sizing …………………………………………………………………………………………………………….. 7
4.5
Program Organiza#on …………………………………………………………………………………………………… 8
4.6
Street Sweeping Equipment ………………………………………………………………………………………….. 8
4.6.1
Equipment Selec#on ………………………………………………………………………………………………… 8
4.6.2
Equipment Maintenance …………………………………………………………………………………………… 8
4.6.3
Equipment Replacement …………………………………………………………………………………………… 8
4.7
Contrac#ng vs. In-House Street Sweeping ………………………………………………………………………. 8
4.8
Other Program Considera#ons ………………………………………………………………………………………. 8
4.8.1
Sweeping Nonstandard Curb Lines……………………………………………………………………………… 8
4.8.2
Wet Weather Prac#ces ……………………………………………………………………………………………… 8
4.8.3
Tree Impacts ……………………………………………………………………………………………………………. 8
4.8.4
Parking Restric#ons and Enforcement ………………………………………………………………………… 8
4.8.5
Interlocal Agreements and Partnerships ……………………………………………………………………… 9
Chapter 5.
OPTIMIZING STREET SWEEPING PRACTICES ………………………………………………………………. 11
5.1
Chapter Introduc#on ………………………………………………………………………………………………….. 11
5.2
Literature Synthesis: Variables that Impact Sweeping Efficiency and Efficacy …………………….. 11
5.3
Performance Measures for Street Sweeping Ac#vi#es ……………………………………………………. 11
5.4
Improving Efficiency and Efficacy of Street Sweeping Prac#ces ………………………………………… 11
5.5
Designing Street Sweeping Routes ……………………………………………………………………………….. 11
5.5.1
Considera#ons when Designing Street Sweeping Routes …………………………………………….. 11
5.5.2
Grids …………………………………………………………………………………………………………………….. 11
5.5.3
Areas …………………………………………………………………………………………………………………….. 11
5.6
Addressing Common Street Sweeping Challenges ………………………………………………………….. 11
Chapter 6.
DOCUMENTING, TRACKING, AND COLLECTING DATA FOR STREET SWEEPING ACTIVITIES .. 13
6.1
Chapter Introduc#on ………………………………………………………………………………………………….. 13
6.2
Data Collec#on ………………………………………………………………………………………………………….. 13
6.2.1
Data to be Collected ……………………………………………………………………………………………….. 13
6.2.2
Supplemen#ng Missing Data ……………………………………………………………………………………. 13
6.3
Tracking …………………………………………………………………………………………………………………….. 13
6.3.1
Informa#on to Track ……………………………………………………………………………………………….. 13
Table of Contents
Street Sweeping Manual | Detailed Manual Outline
iii
6.3.2
Manual Tracking Methods ……………………………………………………………………………………….. 13
6.3.3
Automated Tracking Methods ………………………………………………………………………………….. 13
6.4
Documenta#on and Repor#ng …………………………………………………………………………………….. 13
6.4.1
Permit Documenta#on and Repor#ng Requirements ………………………………………………….. 13
6.4.2
Addi#onal Documenta#on ………………………………………………………………………………………. 14
Chapter 7.
DISPOSING OF STREET SWEEPING WASTE …………………………………………………………………. 15
7.1
Chapter Introduc#on ………………………………………………………………………………………………….. 15
7.2
Applicable Permit Requirements ………………………………………………………………………………….. 15
7.3
Street Sweeping Waste Treatment and Disposal …………………………………………………………….. 15
7.3.1
Wastewater Treatment and Disposal ………………………………………………………………………… 15
7.3.2
Solids Disposal ……………………………………………………………………………………………………….. 15
7.4
Es#ma#ng Generated Waste and Decant Facility Size ……………………………………………………… 15
7.4.1
Es#ma#ng Generated Waste ……………………………………………………………………………………. 15
7.4.2
Decant Facility Sizing ………………………………………………………………………………………………. 15
7.5
Planning, Designing, and Opera#ng Decant Facili#es ……………………………………………………… 15
7.5.1
Decant Facility Planning ………………………………………………………………………………………….. 16
7.5.2
Decant Facility Design …………………………………………………………………………………………….. 16
7.5.3
Decant Facility Opera#ons and Maintenance …………………………………………………………….. 16
Chapter 8.
STREET SWEEPING COST CONSIDERATIONS ……………………………………………………………….. 17
8.1
Chapter Introduc#on ………………………………………………………………………………………………….. 17
8.2
Street Sweeping Staff and Resources ……………………………………………………………………………. 17
8.2.1
Workforce Development Program ……………………………………………………………………………. 17
8.3
Lifecycle Cost Es#ma#ng……………………………………………………………………………………………… 17
8.4
Funding …………………………………………………………………………………………………………………….. 17
8.5
Contrac#ng vs. In-House Street Sweeping …………………………………………………………………….. 17
Chapter 9.
OTHER CONSIDERATIONS ………………………………………………………………………………………… 19
9.1
Chapter Introduc#on ………………………………………………………………………………………………….. 19
9.2
Emerging Contaminants ……………………………………………………………………………………………… 19
9.3
Impacts of Sand and Deicers ……………………………………………………………………………………….. 19
Table of Contents
Street Sweeping Manual | Detailed Manual Outline
Chapter 1. MANUAL INTRODUCTION
Purpose: Describe the manual’s intended use and audience, relevant permit requirements, background
on why the manual was developed, and an overview of the manual organiza#on and content.
1.1
Introduc#on
Introduces manual content and background.
1.2
Manual Background and Purpose
Explains manual purpose, background, intended audience, and how the manual can be used.
1.3
MS4 Permit Requirements
Describes 2024–2029 MS4 Stormwater Permit requirements regarding street sweeping, including
Appendix 6 – Street Waste Disposal; compares Phase I, Phase II Eastern Washington, and Phase II
Western Washington requirements.
1.4
Manual Organiza#on
Lists the manual chapters and a brief descrip#on of their content, including appendices.
Figures
Figure of a street sweeper
Tables
Table comparing the Phase I, Phase II Eastern Washington, and Phase II Western Washington
street sweeping requirements
Appendices
None
Sources
Synthesis of Street Sweeping Research & Pracces Guiding Program Development &
Implementaon, Stormwater Ac#on Monitoring Round 4 Proposal
State of Pracce: Assessing Water Quality Benefits from Street Sweeping by Hixon & Dymond
(2018)
O&M Ad Hoc CommiMee White Paper by Trohimovich, et al. (2022)
Structural Stormwater Controls (SSC) Science Synthesis Project Presenta#on by Ecology (2019)
Street Sweeping Technical Sub-group Scope (2022)
City of Ellensburg Street Sweeping vs Catch Basin Cleaning Effecveness Studies Technical
Evaluaon Report (TER) by Navickis-Brasch, et. al. (2020)
Street Sweeping Manual | Detailed Manual Outline
Chapter 2. STREET SWEEPING BENEFITS
Purpose: Summarize the impacts that street waste can have on water quality and the benefits street
sweeping can provide to reduce those impacts. This chapter will also describe addi#onal benefits of
street sweeping, such as benefits to public health and safety.
2.1
Chapter Introduc#on
Introduces the chapter and summarizes its contents.
2.2
Literature Synthesis
Summarizes the compila#on of research findings regarding characteris#cs of street waste and the
impacts of street sweeping on water quality and public health.
2.2.1…

Draft Outline Comment Log/Responses- Street Sweeping Program Guidance Manual

Summary: Street sweeping manual, comments street sweeping manual, street sweeping manual outline

Commenter, Jurisdiction
Chapter
Section
Comment and Suggested Revision
Comment Response
Jackie Caldwell, City of Vancouver
Overall
N/A
The draft outline looks good, inclusive of all of the topic
information. I don’t have any comments at this time. Great
work!
Thank you!
Abbey Stockwell, Ecology
Purpose
This outline looks good and covers a lot! Couple thoughts:
-Could climate considerations be included for scheduling
and routing
-Add EJ considerations re: scheduling/routing/parking
enforcement
– wet weather practices
Climate considerations will be described in
Section 4.3.3 Scheduling and Section 5.1.1
Considerations When Designing Street Sweeping
Routes. No change proposed to the Final Manual
Outline.
EJ considerations will be described in Sections
4.3.3 Scheduling, 4.8.3 Parking Restrictions and
Enforcement, and 5.1.1 Considerations When
Designing Street Sweeping Routes. No change
proposed to the Final Manual Outline.
A new subsection was added to Section 4.8 Other
Program Considerations to describe best
practices during wet weather.
Foroozan Labib, Ecology
Purpose
Sweeping effectiveness in removing smaller particles
would likely be impacted by wet weather. Rain/runoff can
wash a lot of smaller particles off the street, and these
smaller particles could be temporarily attached to larger
wet particles accumulating in catch basins downstream.
This in turn could influence the decanting operations and
their pollutant removal efficacy.
Noted. This will be considered when describing
impacts of wet weather in Section 4.8.2.
Larry Schaffner, Thurston County
1.3
Be sure to also include a description of Appendix 6 –
Street Waste Disposal
Added, “….including Appendix 6 – Street Waste
Disposal,” to the Section 1.3 description.
Abbey Stockwell, Ecology
1.3
This might be just be MS4 Permit requirements
Revised to MS4 Permit Requirements.
Commenter, Jurisdiction
Chapter
Section
Comment and Suggested Revision
Comment Response
Larry Schaffner, Thurston County
1.4
Include a list and brief description of any appendices’
content.
Added, “….including appendices,” to the Section 1.4
description.
Larry Schaffner, Thurston County
2.2.2
To the extent possible, it would also be informative to
describe how the characteristics differ based on factors
such as roads serving different land use types, AADT levels
and/or road classifications (e.g., local, collector, arterial,
etc.), areas with significant tire wear, and geographical
and seasonal differences.
Added, “This section also describes how street
waste characteristics differ based on factors such
as road classifications, AADT levels, land use
types, areas with significant tire wear,
geographical area, and season,” to section
description.
Larry Schaffner, Thurston County
2.2.3
Should also include the removal efficiency differences of
the various street sweeping technologies.
This topic will be described either in Section 2.2.3
Removal Efficiency or Section 4.6.1 Equipment
Selection. No proposed change to Final Manual
Outline.
Douglas Howie, Ecology
2.2.3
Cite existing studies
A list of existing studies that will be used to
develop Chapter 2 content was added to the Final
Manual Outline.
Sue Barclift, City of Olympia
2.2.4
Title is not clear – Perhaps “Street Pollutant Transport”
Revised title to “Street Pollutant Transport.”
Larry Schaffner, Thurston County
Tables
To the extent that data exists, include table(s)
summarizing the characterizations should also depict
comparative differences on factors such as roads serving
different land use types, AADT levels and/or road
classifications (e.g., local, collector, arterial, etc.), areas
with significant tire wear, and geographical and seasonal
Added, “Tables summarizing differences of street
waste characteristics based on factors such as
road classifications, AADT levels, land use types,
areas with significant tire wear, geographical
area, and season.”
Larry Schaffner, Thurston County
3.3
Suggest folding this in as a subsection to 3.4 since it will be
one of the considerations for identifying and selecting
high-priority street sweeping areas.
Folding Section 3.3 into a subsection of Section 3.4
will be considered when developing Chapter 3.
Abbey Stockwell, Ecology
3.3
The permit refers to priority areas
Revised all instances of “high-priority” to “priority.”
Commenter, Jurisdiction
Chapter
Section
Comment and Suggested Revision
Comment Response
Larry Schaffner, Thurston County
3.5
Suggest folding this in as a subsection to 3.4.
Folding Section 3.5 into a subsection of Section 3.4
will be considered with developing Chapter 3.
Douglas Howie, Ecology
3.5
Industrial areas, areas with significant construction
activity.
Added, “…roads that serve commercial or
industrial land use, areas with significant
construction activity,…” to the Section 3.5
description.
Larry Schaffner, Thurston County
Tables
Table should focus on summarizing applicable MS4 Permit
requirements related to identify high-priority street
sweeping areas.
Revised table description to, “Table summarizing
applicable MS4 Permit requirements related to
identifying priority street sweeping areas. ”
Larry Schaffner, Thurston County
4.2
Also suggest including street sweeping waste disposal.
Added, “…and street waste disposal,” to the Section
4.2 description.
Douglas Howie, Ecology
4.2
Including publicly owned parking areas
Added publicly owned parking areas to the
Section 3.5 description.
Larry Schaffner, Thurston County
4.3
Suggest including a subsection on street sweeping waste
disposal.
Added new Section 4.3.4 Street Waste Disposal.
This section will provide a high-level overview of
street waste disposal and reference Chapter 7.
Sue Barclift, City of Olympia
4.3.2
Consider differences in program size for staffing needs
Differences in program size for staffing needs will
be described in Section 4.3.2. No change proposed
to the Final Manual Outline.
Douglas Howie, Ecology
4.3.2
Include both operation and maintenance staffing, include
need for parts storage
Added a new subsection to Section 4.3 Program
Elements, titled “Operations and Maintenance,”
which describes operations and maintenance
practices for street sweeping programs, including
sufficient storage for street sweepers and
associated equipment. Operations and
maintenance staffing will be described in Section
4.3.2 Staffing.
Commenter, Jurisdiction
Chapter
Section
Comment and Suggested Revision
Comment Response
Sue Barclift, City of Olympia
4.3.5
Suggest training opportunities. I don’t know of any training
courses except by the dealer or manufacturer. Some of
them aren’t feasible to attend. I’ve been considering
developing operator training aimed at water quality
sweeping. Current training focuses on how to operate the
sweeper.
Training opportunities will be suggested based on
findings from literature in Section 4.3.7. No change
proposed to the Final Manual Outline.
Douglas Howie, Ecology
4.6
There is a correlation between sweeping and vactoring
catch basins that should be discussed in this document. I
don’t know if this is the best place to insert the vactor
issue, but it needs to be included here somewhere.
Section 2.2 will include a brief paragraph
describing the correlation between street
sweeping and vactoring catch basins. Analysis
and discussion beyond this it outside of our scope
of work.
Sue Barclift, City of Olympia
4.6.2
Be sure to include cold weather sweeper storage to keep
the water in the water tank and hoses from freezing.
Cold weather sweeper storage will be included in
Section 4.6.2. No change proposed to Final Manual
Outline.
Larry Schaffner, Thurston County
4.7
Recognize that this doesn’t’ necessarily need to be a
binary choice. Rather it could be a hybrid where
contracting supplements the in-house program. Hence,
discussing supplemental contracting would be useful
here.
Revised the first sentence of the section
description to, “Compares the jurisdictional
workload between performing in-house street
sweeping and contracting out a portion of or all
street sweeping services.”
Sue Barclift, City of Olympia
5.5
I started with our policies – we sweep our bike paths every
2 weeks which is most of our arterials.
Considering policies when designing street
sweeping routes was added to Section 5.5.1.
Larry Schaffner, Thurston County
5.5.3
In what context in “basin” used in this subsection (or
perhaps it would be best not to refer to “basin” and gust
leave it as “area”)?
Revised subsection title to, “Areas.”
Commenter, Jurisdiction
Chapter
Section
Comment and Suggested Revision
Comment Response
Douglas Howie, Ecology
5.5
This may be a good place to describe the issues with
decant water collecting in the sweeper and how to
dispose of it as efficiently as possible while still meeting
the permit discharge requirements.
Challenges with decant water collecting in the
sweeper and how to efficiently dispose of it while
still meeting the MS4 Permit discharge
requirements will be described in Sections 5.5.1,
5.6, and 7.3.1.
Sue Barclift, City of Olympia
5.6
Mention the issue of sweeping during rain events & wet
roads in general. Water fills the hopper quickly & it’s not
feasible to decant often (can fill after sweeping 10 blocks).
Also, the hose attached to the hopper releases water and
releases fines that were collected.
Challenges of sweeping during rain events will be
included in Section 5.6. The section description
includes, “…sweeping during leaf season,
inclement weather, and minimizing trips to the
dewater/decant facility.”
Sue Barclift, City of Olympia
5.6
Need to consider scheduling conflicts such as
garbage/recycle pickup days and special events – school
schedules, construction, paving, street painting. Work with
other depts for seasonal scheduling.
Scheduling conflicts will be described in Section
4.3.3. No change proposed to the Final Manual
Outline.
Larry Schaffner, Thurston County
5.6
Another challenges involve minimizing traffic disruptions
and strategies for dealing with alternative parking options
during sweeping operations.
The section description was revised to include
minimizing traffic disruptions. Strategies for
dealing with alternative parking options will be
described in Section 4.8.3.
Douglas Howie, Ecology
5.6
Include parked vehicles along curb line
The section description was revised to include
parked vehicles along the curb line.
Mark Melton, Ecology
5.6
Consider including snow and inclement weather
The section description was revised to include
inclement weather.
Don McQuilliams, Bellevue WA
5.6
Add pavement deficiencies to the problems list (i.e. roots
lifting pavement or settling uneven pavement).
The section description was revised to include
pavement deficiencies.
Commenter, Jurisdiction
Chapter
Section
Comment and Suggested Revision
Comment Response
Larry Schaffner, Thurston County
6.2
Please elaborate on the relevance/purpose regarding
“who may potentially collect data.”
Who may potentially collect data and its
importance will be described in Section 6.2. No
change proposed to the Final Manual Outline.
Larry Schaffner, Thurston County
6.3
Beyond MS4 Permit-driven documentation and reporting,
suggest including considerations related to business-
related drivers (e.g., improving program efficiency and
efficacy).
Beyond MS4 Permit-driven documentation and
reporting, such as metrics related to business-
related drivers will be included in Section 6.4.2. No
change proposed to Final Manual Outline.
Douglas Howie, Ecology
6.4
Note that documentation for meeting permit requirements
for sweeping and obtaining SMED points are related but
different.
Noted. Additional documentation will be
described in Section 6.4.2. No change proposed to
Final Manual Outline.
Jim Crawford/King County Roads
6.4.1
Include Health Dept Tracking and Reporting Requirements
under Solid Waste Handling Standards. (Storage &
inspection requirements & annual tracking of amounts
generated and disposed). Source: WAC Title 173 Chapter
173-350
The section description was revised to include
WAC Title 173 Chapter 173-350 Solid Waste
Handling Standards.
Jim Crawford/King County Roads
7.2
Appendix 6 AND WAC Title 173 Chapter 173-350-320
The section description was revised to include
WAC Title 173 Chapter 173-350-320.
Don McQuilliams, Bellevue WA
7.2
Add permitting requirements around operation of a
decant facility beyond the NPDES requirements (i.e.
wastewater discharge permit, industrial landfill permit).
Added, “This section also describes potentially
applicable wastewater discharge and industrial
landfill permits,” to the Section 7.2 description.
Larry Schaffner, Thurston County
7.3
Information could also be useful in calculating street
waste disposal costs.
Using information in Section 7.3 to calculate street
waste disposal cost will be described and
reference Chapter 8. No change proposed to Final
Manual Outline.
Commenter, Jurisdiction
Chapter
Section
Comment and Suggested Revision
Comment Response
Sue Barclift, City of Olympia
7.3.1
Be sure to add a disclaimer for your spreadsheet. This is so
hard to predict due to weather (snow/no snow, rain/storm
frequency and operator availability (vacations, sick leave,
operator retention).
A disclaimer will be added to all
tools/spreadsheets developed as part of this
manual.
Douglas Howie, Ecology
Purpose
Not just a decant facility. What happens when sweeping
during rain events and need to unload water from the
sweeper without going to the decant facility? This is a
serious issue that needs to be discussed.
The Purpose of the chapter was revised to include,
“Provide guidance for disposing of street sweeping
waste, both liquids and solids.” A new section titled
Street Sweeping Waste Treatment and Disposal
was added to Chapter 7 that describes the
treatment and disposal of street sweeping liquid
and solid waste.
Larry Schaffner, Thurston County
8.3
If not covered in Chapter 7, suggest touching upon costs
related to decant and street waste disposal.
Decant and street waste disposal costs will be
included in Chapter 7. No change proposed to
Final Manual Outline.
Sue Barclift, City of Olympia
8.4
Encourage funding for the planning stage – decant facility
design and enhanced street sweeping plan before
applying for a street sweeper grant.
Encouraging funding for the planning stage will be
included in Section 8.4. No change proposed to
Final Manual Outline.
Larry Schaffner, Thurston County
8.4
Will this cover funding associated with operations, capital,
both?
Funding described in Section 8.4 will include
funding associated with operations and capital.
This topic will be added to the list of potential case
studies. No change proposed to Final Manual
Outline.

Street Sweeping Manual Draft Concept Chapter Survey Results

Summary: street sweeping manual survey, street sweeping survey results

Street Sweeping Research & Practices Synthesis:
Guiding Program Development & Implementation
Statewide Survey Questions & Results
May 29, 2024
Street Sweeping Research & Practices Synthesis: Guiding Program Development & Implementation |
Statewide Survey Questions & Results
Table of Contents
Table of Contents …………………………………………………………………………………………………………………………. i
Survey Background ……………………………………………………………………………………………………………………… 1
Survey Questions & Results ………………………………………………………………………………………………………….. 2
Street Sweeping Research & Practices Synthesis: Guiding Program Development & Implementation |
Statewide Survey Questions & Results 1
Survey Background
A statewide survey was developed to support the development of the Synthesis of Street Sweeping
Research & Practices: Guiding Program Development & Implementation project. This project aims to
develop a guidance manual that will provide information and tools Permittees can use to assist with
developing and/or improving their street sweeping program to support compliance with the anticipated
2024–2029 Municipal Separate Storm Sewer (MS4) Permit requirements. The intention of this survey
was to gain a better understanding of Permittees’ priorities to inform manual content development. Both
administrative and field staff were encouraged to respond. The statewide survey consisted of 14
questions with different response options, including multiple choice, fill in the blank, and selecting
prioritized options. A total of 46 respondents completed the survey. Each survey question and the
corresponding results are presented below. Results are shown as (number of responses, percent of total
responses). The following section is a summary of the survey questions and results.
Street Sweeping Research & Practices Synthesis: Guiding Program Development & Implementation |
Statewide Survey Questions & Results 2
Survey Questions & Results
1. What MS4 Permit was your jurisdiction issued or will be issued? (Select one)
2. What is the population residing within your jurisdiction's MS4 permit regulated area? (Select one)
6; 13.0%
3; 6.5%
33; 71.7%
2; 4.3%
10%
20%
30%
40%
50%
60%
70%
80%
a. Phase I Permit
b. EWA Phase II Permit
c. WWA Phase II Permit
d. WSDOT
e. Other (Unknown)
MS4 Permit Jurisdiction
0; 0.0%
18; 39.1%
14; 30.4%
4; 8.7%
10; 21.7%
10%
15%
20%
25%
30%
35%
40%
45%
a. less than 10,000
b. 10,000-50,000
c. 50,000-150,000
d. 150,000-250,000
e. greater than 250,000
Population within MS4
Street Sweeping Research & Practices Synthesis: Guiding Program Development & Implementation |
Statewide Survey Questions & Results
3. What best describes your role at your jurisdiction? (Select one)
4. The project team developed the following conceptual chapter outline before submitting the
proposal. The outline was developed based on discussions with regional stormwater work groups,
consideration for the tools needed to meet anticipated MS4 Permit requirements, and professional
judgment. On a scale of 3 being high importance and 1 being low importance, indicate the level of
importance of the following chapter concepts. If a chapter does not appear on the list that you believe
is important, please add it to the text box below.
Topic
Average Score
(1–3)
Standard
Deviation
Water quality benefits of street sweeping
2.57
0.61
Identifying high priority street sweeping areas
2.65
0.63
Establishing new street sweeping programs
1.91
0.75
Optimizing existing street sweeping programs
2.61
0.61
Documenting and Tracking Street Sweeping Activities
2.46
0.65
Street sweeping waste disposal
2.41
0.77
Street sweeping program cost considerations
2.50
0.54
24; 50.0%
14; 29.2%
6; 12.5%
1; 2.1%
20%
40%
60%
a. Stormwater Program Coordinator/Manager
b. Responsible for overseeing the street sweeping
program
c. Responsible for implementing the street sweeping
program
d. Street sweeping Operator
e. Other (Source Control Inspector, former Street
Sweeper Operator)
e. Other (Assists with Health Department Permits
for pile storage compliance)
e. Other
Responder Role in Jurisdiction
Street Sweeping Research & Practices Synthesis: Guiding Program Development & Implementation |
Statewide Survey Questions & Results
1. Water Quality Benefits of Street Sweeping
2. Identifying High Priority Street Sweeping Areas
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
3; 6.5%
14; 30.4%
29; 63.0%
Water Quality Benefits of Street Sweeping
1 – Low Importance
2 – Medum Importance
3 – High Importance
4; 8.7%
8; 17.4%
34; 73.9%
Identifying High Priority Sweeping Areas
1 – Low Importance
2 – Medum Importance
3 – High Importance
Street Sweeping Research & Practices Synthesis: Guiding Program Development & Implementation |
Statewide Survey Questions & Results
3. Establishing New Street Sweeping Programs
4. Optimizing Existing Street Sweeping Programs
15; 32.6%
20; 43.5%
11; 23.9%
Establishing New Street Sweeping Programs
1 – Low Importance
2 – Medum Importance
3 – High Importance
3; 6.5%
12; 26.1%
31; 67.4%
Optimizing Existing Street Sweeping
Programs
1 – Low Importance
2 – Medum Importance
3 – High Importance
Street Sweeping Research & Practices Synthesis: Guiding Program Development & Implementation |
Statewide Survey Questions & Results
5. Documenting and Tracking Street Sweeping Activities
6. Street Sweeping Waste Disposal
4; 8.7%
17; 37.0%
25; 54.3%
Documenting & Tracking Street Sweeping
Activities
1 – Low Importance
2 – Medum Importance
3 – High Importance
8; 17.4%
11; 23.9%
27; 58.7%
Street Sweeping Waste Disposal
1 – Low Importance
2 – Medum Importance
3 – High Importance
Street Sweeping Research & Practices Synthesis: Guiding Program Development & Implementation |
Statewide Survey Questions & Results
7. Street Sweeping Program Cost Considerations
If an area of importance does not appear above, please add it here.
Theme
Survey Response
Post Survey Notes
Addressed in Current Manual
Concept?
Rules and Regulations
• “Knowing and understanding the
rules or regulations”
Permit requirements will be addressed
in Chapter 1 Manual Introduction
Equipment/Machinery
• “Overview of sweeping machines
and sweeping methods/efficiencies
(such as sweeping on a damp day is
more effective to capture materials)”
• “Would like to get better
understanding about allowing water
to run off of sweeper in our heavy
rain season that happens to fall in
our heaviest leaf season. We are told
we can't but not one sweeper
company has a filter system built to
allow this.”
• Planned to include Chapter 4
Establishing New Street Sweeping
Programs.
• Could be addressed in Chapter 4
Establishing New Street Sweeping
Programs.
Sweeping Methods,
Planning, and
Improving Efficiency
• “Route development and sweeping
schedule optimization”
Planned to include Chapter 5
Optimizing Existing Street Sweeping
Programs.
Water Quality
Benefits/Impacts
• “Adaptive management: We need
more 6PPD fate & transport research
to know if street sweeping is
effective. Allowing the particles to sit
in the sun during dry periods may
ozonate the 6PPD out, sweeping may
consolidate 6PPD, fine vs. course
sweepers.”
• Addressed in Chapter 2 Water
Quality Benefits literature search
(status of current research), Could
also be included in Research Gaps
and Recommendations document.
• Could be included in Chapter 2
Water Quality Benefits.
1; 2.2%
21; 45.7%
24; 52.2%
Street Sweeping Program Cost
Considerations
1 – Low Importance
2 – Medum Importance
3 – High Importance
Street Sweeping Research & Practices Synthesis: Guiding Program Development & Implementation |
Statewide Survey Questions & Results
Theme
Survey Response
Post Survey Notes
Addressed in Current Manual
Concept?
• “The pollution generated by
increased street sweeping offsets is
at odds with the water quality
benefits of increased street
sweeping”
Testing
• “List what contaminants in sweep
waste should be tested.”
Could be included in Chapter 7 Street
Sweeping Waste Disposal.
Funding
• “Funding for additional equipment
and labor/disposal due to the
increased sweeping requirements.”
Addressed in Chapter 8 Street
Sweeping Program Cost
Considerations.
Additional Cost
Considerations
• “Cost of permit compliance for
temporary disposal of sweepings as
a sub-category of Program cost
considerations.”
Could be included in Chapter 8 Street
Sweeping Program Cost
Considerations.
Additional Comments
• “For the two areas I didn't score
high, I believe we'll get this
information in a separate report (but
maybe not other than 6PPD-q) and
Ecology is identifying the high
priority areas for us in the permit so I
scored that lower.”
Street Sweeping Research & Practices Synthesis: Guiding Program Development & Implementation | Statewide Survey Questions & Results
5. During the regional stormwater work group meetings, Permittees identified the following additional topics they would like included
in the street sweeping program manual. Please select the top 10 topics you feel are most important to include in the manual.
Topic
Selections
Percentage
Using street sweeper tracking data to improve program efficiency
8.2%
Methods to assess and prioritize roads (beyond what is required in the Permit) based on variables (weight,
bus/truck route, velocity, traffic density, start/stops)
6.4%
Methods for identifying when decant materials need to be sampled
6.2%
Addressing challenges such as protruding tree limbs, non-standard curbs, and street sweeping during leaf season
5.9%
Sweeping different types of surfaces, including permeable pavements
5.7%
Addressing labor and equipment issues, such as hiring enough staff and purchasing street sweepers
5.7%
Methods to minimize trips to the dewater/decant facility
5.5%
Effectiveness of sweeping curb vs non-curb roads
5.5%
Information or data a jurisdiction might collect to refine a program
5.5%
Program funding options
5.3%
Street sweeping program staff training
5.3%
Cost considerations for testing street waste to determine if it is hazardous waste
4.8%
Cost summary of implementing street sweeping requirements in the
Draft 2024-2029 Phase II Permits
4.8%
Parking policies and enforcement options
4.8%
Comparison of cost between street sweeping and vactoring catch basins
4.6%
Methods to effectively sweep areas that are too narrow for a full-size sweeper (e.g., protected bike lanes)
3.7%
Street sweeper size/type vs cost tradeoff (i.e., a larger sweeper will make less dewatering/decant trips but will
cost more to purchase and operate)
3.7%
Ongoing maintenance and staffing requirements required to operate a decant facility
3.4%
Sweeping non-street locations (e.g., parking lots, pathways)
3.0%
Interlocal agreements and community-based public/private partnerships
2.3%
Street Sweeping Research & Practices Synthesis: Guiding Program Development & Implementation |
Statewide Survey Questions & Results 10
6. Does your jurisdiction have access to a decant facility? (Select one)
7. If yes, does the decant facility reside within your jurisdiction? (Select one)
8. How far must the operators travel to access the decant facility? (Fill in the blank)
41; 89.1%
4; 8.7%
1; 2.2%
20%
40%
60%
80%
100%
a. Yes
b. No
c. Unsure
Decant Facility Access
38; 82.6%
2; 4.3%
6; 13.0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
a. Yes
b. No
c. N/A
Decant Facility Within Jurisdiction
17; 37.0%
4; 8.7%
8; 17.4%
5; 10.9%
12; 26.1%
10%
15%
20%
25%
30%
35%
40%
5-10
10-20
20+
N/A or No Information
Distance in Miles to Decant Facility
Appendix Y
Appendix Name
Street Sweeping Research & Practices Synthesis: Guiding Program Development & Implementation |
Statewide Survey Questions & Results
9. If decant facility access requires traveling to another jurisdiction, does the travel distance pose an
acceptable burden, or does it greatly hinder your sweeping program's efficiency? (Select one)
10. For jurisdictions with access to a decant facility, is the decant facility at or near capacity? (Select one)
11. How prepared is your jurisdiction to implement a street sweeping program for water quality
purposes? (Select one)
1; 2.2%
12; 26.1%
33; 71.7%
10%
20%
30%
40%
50%
60%
70%
80%
a. Acceptable
b. Impacts sweeping efficiency
c. N/A
Decant Facility Travel Distance Impact
15; 32.6%
13; 28.3%
14; 30.4%
4; 8.7%
10%
15%
20%
25%
30%
35%
40%
a. Yes, near capacity
b. No, there is additional capacity available
c. Unsure
d. N/A
Decant Facility Capacity
11; 23.9%
9; 19.6%
17; 37.0%
9; 19.6%
10%
15%
20%
25%
30%
35%
40%
a. Our program requires a lot of work
b. Only minor improvements are needed
c. Our program is ready now
d. Not sure
Jurisdiction Preparedness
Appendix Y
Appendix Name
Street Sweeping Research & Practices Synthesis: Guiding Program Development & Implementation |
Statewide Survey Questions & Results
What do you need to be ready that could be included in the manual that has not already been
mentioned? (Fill in the blank)
Theme
Survey Response
Post Survey Notes
Addressed in Current
Manual Concept?
Equipment
• “Type of sweeper needed. We only have a
mechanical sweeper, and contract out
regenerative air vac sweepers.”
• “Addressing moving from an internal
combustion engine sweeper to an electric
or potentially a hydrogen sweeper. What
are the impacts(environmentally, cost,
availability etc.), what grant funding is
available, how to propose for a grant etc.”
• Addressed in Chapter 4
Establishing New Street
Sweeping Programs.
• Could be included in
Chapter 4 Establishing New
Street Sweeping Programs.
Measuring, Assessing,
and Tracking Program
Performance
• “How to practically or simply measure
sweeping effectiveness for program
modification”
• “Methods to develop a street sweeping
schedule, developing the schedule,
delineation of routes or areas (for tracking
purposes) called out in the schedule, and
anticipating budget and staffing to run the
street sweeping program.”
Addressed in Chapter 5
Optimizing Existing Street
Sweeping Practices
Staff and Training
• “Priority for an expanded sweepings
program is sufficient, Trained Staff
(significant issue due to large amount of
turnover since COVID), equipment & plans
for dealing with equipment maintenance.
These items are issues for existing
programs.”
• “I feel many municipalities will need
additional staffing as well as equipment. I
think we do a good job but when it is wet
or during leaf season we slow way down
when I think it is most important and the
only thing that would help is additional
staff”
Addressed in Chapter 4
Establishing New Street
Sweeping Programs.
Decant Facilities
• “Establishing a decant facility”
• “Additional sweeper, staff and an
additional decant facility/potentially a new
solid waste handling permit if waste is
deemed hazardous.”
Addressed in Chapter 7
Disposing of Street Sweeping
Waste.
Sweeping Schedule and
Establishing Routes
• “Adding new routes to meet the permit
requirements; how to optimize the…

Draft Street Sweeping Manual Concept Chapters Outline

Summary: Concept chapters street sweeping, road maintenance

Ecology | Synthesis of Street Sweeping Research & Practices
ATTACHMENT A-1
Table 4. Street Sweeping Guidance Manual Concept Outline
CHAPTER 1. MANUAL INTRODUCTION
Purpose: Describe the manual’s intended use and audience, relevant permit requirements,
background on why the manual was developed, and an overview of the manual
organization and content.
CHAPTER 2. STREET SWEEPING WATER QUALITY BENEFITS
Purpose: Summarize the impacts that street waste can have on water quality and the
benefits street sweeping can provide to reduce those impacts.
CHAPTER 3. IDENTIFYING HIGH PRIORITY AREAS
Purpose: Provide guidance to assist Permittees in identifying their specific high priority
areas for their street sweeping program using information from Chapter 2 and available
jurisdictional information.
CHAPTER 4. ESTABLISHING AND IMPROVING STREET SWEEPING PROGRAMS
Purpose: Introduce street sweeping program elements; guidance for defining program
goals, starting new programs, and right sizing street sweeping programs; selecting
equipment; and developing/selecting a defendable way to assess and measure program
benefits. Guidance for how to establish and organize multi-department collaborations
that support street sweeping programs.
CHAPTER 5. OPTIMIZING STREET SWEEPING PRACTICES
Purpose: Provide guidance for designing sweeping routes, improving efficiency/efficacy of
existing programs including instructions for collecting data, and variables that may
influence efficiency/efficacy. This chapter will also include guidance for developing
performance measures for street sweeping activities.
CHAPTER 6. DOCUMENTING AND TRACKING STREET SWEEPING ACTIVITIES
Purpose: Provide guidance for documenting and tracking sweeping activities to assist
Permittees with MS4 Permit compliance and tracking program costs.
CHAPTER 7. DISPOSING OF STREET SWEEPING WASTE
Purpose: Provide guidance for estimating the quantity of waste generated from street
sweeping based on specific jurisdictional conditions (i.e., road-miles, sweeping frequency,
land use, traffic volumes, climate, tree-cover, etc.). The guidance will be used to develop a
spreadsheet that Permittees can use to input jurisdictional conditions to estimate the
amount of waste generated and another that estimates the number and size of decant
facilities needed. Considerations will be provided for waste water treatment and disposal
locations and planning for designing/constructing/operating a decant facility.
CHAPTER 8. COST CONSIDERATIONS FOR ESTABLISHING AND MAINTAINING PROGRAMS
Purpose: Provide guidance for estimating street sweeping program costs using
information collected by the jurisdiction or information collected from literature/surveys
(for jurisdictions without data). This will include developing a spreadsheet for conducting a
lifecycle cost estimate and projecting costs based on growth. Information about potential
funding sources will also be provided.
CHAPTER 9. OTHER CONSIDERATIONS
Purpose: Discuss topics that do not fit in other chapters, but Permittees may need to know
when implementing a street sweeping program (e.g., emerging contaminants, when/why
to test waste, etc.)

EWA Phase II Permit Compliance Table 2019 Permit Cycle

Summary: EW Compliance Table, Ecology timelines by permit condition 2019 permit

EWA Phase II Compliance Table
Page 1
Disclaimer: The Compliance Table for the Eastern Washington MS4 Permit lists specific tasks and due
dates as guidance only. Any inadvertent discrepancies provided in this Table do not change the
requirements established by the 2019 Eastern Washington Phase II Municipal Stormwater NPDES
Permit.
Compliance with Standards
Permit Section
Deliverable
Due Date
S4.F.1
Notify Ecology in writing when becoming aware
that a discharge from the MS4 is causing or
contributing to a known or likely violation of
Water Quality Standards.
Within 30 days of becoming
aware of discharge.
S4.F.3
Review and revise Stormwater Management
Program to meet AKART, and submit a report to
Ecology.
Within 60 days of receiving
Ecology notice, or date
established by Ecology.
Stormwater Management Program
Permit Section
Deliverable
Due Date
S5.A.1
New Permittees – Develop and implement a
Stormwater Management Program, including the
SWMP Plan.
New Permittees – February 2,
2024. Annually, thereafter.
S5.A.4
Update Stormwater Management Program Plan
of required activities and actions for the
upcoming year.
Submit with Annual Report
by March 31.
S5.A.5.a.i
Track number of activities implemented for each
SWMP component.
Ongoing
New Permittees – August 1,
2021
S5.A.5.a.ii
Track estimated cost of development and
implementation of each SWMP component.
Provide to Ecology upon
request.
S5.A.6.b
Written description of internal coordination
process among departments.
Submit with Annual Report
by March 31, 2021.
Page 2
Public Education and Outreach
Permit Section
Deliverable
Due Date
S5.B.1
Implement Education and Outreach Program.
Ongoing
New Permittees – August 1,
2021
S5.B.1.b
Footnote 4
Measure understanding and adoption of targeted
behaviors for at least 1 target audience in at least
1 subject area. Use results of education and
outreach measurements to direct resources.
December 31, 2021
New Permittees – August 1,
2023
Public Involvement and Participation
Permit Section
Deliverable
Due Date
S5.B.2.a
Implement Program or policy for public input.
Document in SWMP.
Ongoing
New Permittees – August 1,
2020
S5.B.2.b
Post on website and make the latest version of
Annual Report and SWMP available to public.
Annually – May 31
Illicit Discharge Detection and Elimination (IDDE)
Permit Section
Deliverable
Due Date
S5.B.3
Footnote 6
Implement and enforce an IDDE Program to
prevent, detect, characterize, trace, and
eliminate illicit discharges into MS4.
Ongoing
New Permittees – August 1,
2021
S5.B.3.a
Footnote 7
Update map of MS4.
August 1, 2023
New Permittees – February 2,
2024
S5.B.3.a.v
Document connections to the MS4 authorized or
approved after August 1, 2019.
August 1, 2023
S5.B.3.a.ix
Electronic mapping format required with fully
described mapping standards.
August 1, 2021
S5.B.3.b.i,
Footnote 6
New Permittees – Implement ordinance or
regulatory mechanism to prohibit illicit
discharges and authorize enforcement actions.
New Permittees – August 1,
2021
Page 3
Permit Section
Deliverable
Due Date
S5.B.3.b.vii
Revise regulatory mechanism to meet
requirements of conditionally allowable and
prohibited non-stormwater discharges.
February 2, 2023
S5.B.3.c.iv
Footnote 9
Field assess at least 12%, on average, of MS4
within coverage area each year. Track total
cumulative percentage of MS4 assessed.
Ongoing. Beginning August 1,
2019.
New Permittees – December
31, 2023. Ongoing,
thereafter.
S5.B.3.c.vii
Footnote 10
Inform public employees, businesses, and
general public of hazards of illicit discharges and
improper disposal of waste.
August 1, 2019
New Permittees – August 1,
2022
S5.B.3.d
Footnote 11
Implement program, including procedures, to
address illicit discharges, illicit connections, and
spills into the MS4.
Ongoing
New Permittees – August 1,
2023. Ongoing, thereafter.
S.5.B.3.d.iv.(a)
S5.B.3.d.iv.(b)
S5.B.3.d.iv.(c)
S5.B.3.d.iv.(d)
Respond to all illicit discharges into the MS4,
determined to constitute a threat to human
health, welfare, or the environment, consistent
with G3.
Investigate or refer complaints, reports, or
monitoring information that indicates a potential
illicit discharge.
Investigate or report complaints, reports, or
monitoring information that indicates a potential
illicit connection. Initiate investigation to
determine source, ownership and volume of
discharge
Use compliance strategy to eliminate confirmed
illicit connection.
Immediately
Within 7 days.
Within 21 days.
Within 6 months.
S5.B.3.e
Train staff responsible for illicit discharge
response. Document and maintain records of
training provided and staff trained.
Ongoing. Follow-up, as
needed.
New Permittees – August 1,
2021. As needed, thereafter.
Page 4
Permit Section
Deliverable
Due Date
S5.B.3.f,
Appendix 7
Track and maintain records of IDDE activities.
Summarize all data for illicit discharges, illicit
connections, and spills found, reported, or
investigated during previous calendar year.
Document IDDE incidents in WQWebIDDE or
compatible spreadsheet according to Appendix 7.
Document IDDE incidents in WQWebIDDE or
submit data tracking system schema in a zipped
.xml according to Appendix 7.
Submit with Annual Report
by March 31.
March 31, 2021
March 31, 2022
Construction Site Stormwater Runoff Control
Permit Section
Deliverable
Due Date
S5.B.4
Implement and enforce a Construction Site
Stormwater Runoff Control Program to reduce
pollutants in stormwater from construction
activities that disturb one acre or more, or are
part of a common plan of development.
Ongoing
New Permittees – December
31, 2022
S5.B.4.a
Adopt and have an effective ordinance or
enforceable mechanism to ensure compliance
with construction site stormwater controls.
December 31, 2022
New Permittees – December
31, 2022
S5.B.4.b
Implement procedures for site plan review, which
incorporates consideration of water quality
impacts.
Ongoing
New Permittees – December
31, 2022
S5.B.4.b.i
Review SWPPPs prior to clearing and
construction.
Ongoing
S5.B.4.c
Implement procedures for construction site
inspection and enforcement on >80% of sites.
Qualified personnel to inspect:
(a) Prior to clearing and grading on sites with
high potential for sediment transport.
(b) During construction to verify proper ESC
BMP installation and maintenance. Follow
up, as necessary.
Ongoing
New Permittees – December
31, 2022
Page 5
Permit Section
Deliverable
Due Date
5.B.4.d
Train all staff involved with permitting, plan
review, construction site inspections, and
enforcement.
Ongoing. Follow-up, as
needed.
New Permittees – December
31, 2022. Follow-up, as
needed.
S5.B.4.e
Provide information on construction stormwater
training to construction site operators, staff, and
design professionals.
Ongoing
New Permittees – December
31, 2022
S5.B.4.f
Keep records of all training, site plan reviews,
inspections, and enforcement actions on
construction projects >1 acre or part of a
common plan of development.
Keep copies of information provided to
construction site operators.
Keep records of construction sites that apply for
the Erosivity Waiver.
For 5 years or until project is
complete, whichever is
longer.
Ongoing
Post-Construction Stormwater Management
Permit Section
Deliverable
Due Date
S5.B.5
Implement and enforce a Post-Construction
Stormwater Management Program to address
post-construction runoff to the MS4.
Ongoing
New Permittees – December
31, 2022
S5.B.5.a
Implement a regulatory mechanism that requires
post-construction stormwater controls at new
and redevelopment projects.
(See Permit for applicable submittal dates of
applications.)
December 31, 2022
S5.B.5.b.ii.(b)(3)
New Permittees – Develop criteria defining
infeasibility of meeting S5.B.5.b.ii.(b)(2) (retaining
10-year event runoff), if not already meeting
requirement.
New Permittees – Submit
with Annual Report by March
31, 2022.
Page 6
Permit Section
Deliverable
Due Date
S5.B.5.d.i-ii
Implement procedures for site inspection and
enforcement of post-construction structural
BMPs. Qualified personnel to inspect BMPs:
ï‚· At least once during installation.
ï‚· Upon final installation or project completion.
ï‚· At least once every 5 years.
Ongoing
New Permittees – December
31, 2022
S5.B.5.e
Provide training to all staff involved with
permitting, planning, review, inspection, and
enforcement.
Ongoing. Follow up, as
needed.
New Permittees – December
31, 2022. Follow-up, as
needed.
S5.B.5.g
Keep records of all projects >1 acre or part of a
common plan of development.
For 5 years or until project is
complete, whichever is
longer.
Municipal Operations and Maintenance
Permit Section
Deliverable
Due Date
S5.B.6
Footnote 15
Implement an Operations and Maintenance
Program to prevent or reduce pollutant runoff
from municipal operations.
Ongoing
New Permittees – December
31, 2023
S5.B.6.a
Implement a schedule of municipal Operation
and Maintenance activities (an O&M Plan).
Review and, if needed, update the Operations
and Maintenance Plan.
Ongoing. December 31, 2022.
New Permittees – December
31, 2023
S5.B.6.a.i.(h)
Implement site-specific SWPPPs for all material
storage areas, heavy equipment storage areas,
and maintenance areas.
December 31, 2022
New Permittees – December
31, 2023
S5.B.6.a.ii.(a)-(b) Inspect 95% of all stormwater treatment and flow
control facilities every 2 years. Inspect all catch
basins and inlets every 2 years.
Ongoing
New Permittees – December
31, 2023. Every 2 years
thereafter.
S5.B.6.a.ii.(c)
Spot check treatment and flow control facilities
for potential damage, and repair as soon as
practicable.
After 10-year/24-hour storm
event.
Page 7
Permit Section
Deliverable
Due Date
S5.B.6.b
Provide and document training for all employees
with primary construction, operations, or
maintenance job functions.
Ongoing. Follow-up, as
needed.
Stormwater Management Program for Secondary Permittees
Permit Section
Deliverable
Due Date
S6.A.2-4
Develop and implement a Stormwater
Management Program; or,
Secondaries with a local MOU or agreement may
implement parts in accordance with their signed
MOU or Agreement with a local jurisdiction(s).
Ongoing or alternate
implementation schedule.
New Secondary Permittees –
4.5 years from initial
coverage date.
Public Education and Outreach for Secondary Permittees
Permit Section
Deliverable
Due Date
S6.D.1
Implement stormwater education strategies.
Ongoing
New Secondary Permittees –
4.5 years from initial Permit
coverage date.
S6.D.1.a
Footnote 17
Label all inlets, “Dump no Waste – Drains to
Waterbody”. Relabel unreadable labels during
visual inspection and maintenance of drain inlets.
Ongoing. Within 90 days of
discovery.
New Secondary Permittees –
4 years from initial date of
Permit coverage. Within 90
days of discovery, thereafter.
S6.D.1.b
Distribute stormwater educational materials to
identified public.
Ongoing
New Secondary Permittees –
3 years from initial date of
Permit coverage.
Public Involvement and Participation for Secondary Permittees
Permit Section
Deliverable
Due Date
S6.D.2.a-b
Make current Annual Report and updated SWMP
Plan available on website.
Annually – May 31
Page 8
Illicit Discharge Detection and Elimination for Secondary Permittees
Permit Section
Deliverable
Due Date
S6.D.3.a
Comply with relevant ordinances, rules, and
regulations of local jurisdictions.
Upon initial date of Permit
coverage.
S6.D.3.b
Footnote 18
Implement policies prohibiting illicit discharges.
New Secondary Permittees – Develop and
implement policies prohibiting illicit discharges
and identify enforcement mechanisms.
Ongoing
New Secondary Permittees –
1 year from initial date of
Permit coverage.
S6.D.3.b
Footnote 19
Implement an enforcement plan to ensure
compliance with illicit discharge policies.
New Secondary Permittees – Develop and
implement an enforcement plan.
Ongoing
New Secondary Permittees –
18 months from initial date
of Permit coverage.
S6.D.3.c
Footnote 20
Maintain a storm sewer system map of known
storm drain outfalls and discharge points,
labeling receiving waters, and delineating
contributing areas.
Ongoing
New Secondary Permittees –
4.5 years from initial date of
Permit coverage.
S6.D.3.d
Footnote 21
Inspect at least 1/3 of known outfalls and
discharge points, and remove illicit discharges.
Keep records of field inspections.
New Secondary Permittees – Develop and
implement procedures to identify, inspect, and
remove any illicit discharges. Begin inspecting 1/3
of known outfalls and discharge points.
Ongoing
New Secondary Permittees –
2 years from initial date of
Permit coverage.
S6.D.3.e
Footnote 22
Implement a spill response plan.
Ongoing
New Secondary Permittees –
4.5 years from initial date of
Permit coverage.
S6.D.3.f
Provide staff training on BMPs for preventing
illicit discharges.
Ongoing. Follow-up, as
needed.
New Secondary Permittees –
2 years from initial date of
Permit coverage. Follow-up,
as needed.
Page 9
Construction Site Stormwater Runoff Control for Secondary Permittees
Permit Section
Deliverable
Due Date
S6.D.4.a
Comply with all relevant construction stormwater
ordinances, rules, and regulations of local
jurisdictions.
Upon initial date of Permit
coverage.
S6.D.4.b
Where necessary, obtain a Construction
Stormwater General Permit (CSWGP) for
construction projects.
Upon initial date of Permit
coverage.
S6.D.4.c
Provide staff training on erosion and sediment
control BMPs and requirements.
Upon initial date of Permit
coverage.
Post-Construction Stormwater Management for Secondary Permittees
Permit Section
Deliverable
Due Date
S6.D.5.a
Comply with all relevant post-construction
stormwater ordinances, rules, and regulations of
local jurisdictions.
Upon initial date of Permit
coverage.
S6.D.5.b
Coordinate with the local jurisdiction regarding
projects owned by other entities that discharge
into the MS4.
Upon initial date of Permit
coverage.
Pollution Prevention for Municipal Operations for Secondary Permittees
Permit Section
Deliverable
Due Date
S6.D.6.a
Footnote 23
Implement an Operation and Maintenance
(O&M) Plan for operations, activities, and/or
facilities.
New Secondary Permittees – Develop and
implement an Operation and Maintenance Plan.
Ongoing
New Secondary Permittees –
3 years from initial date of
Permit coverage.
S6.D.6.a.i
Regularly inspect and maintain all stormwater
facilities.
Ongoing
New Secondary Permittees –
3 years from initial date of
Permit coverage.
Page 10
Permit Section
Deliverable
Due Date
S6.D.6.a.i
Spot check treatment and flow control
stormwater facilities.
After 10-year/24-hour storm
event.
New Secondary Permittees –
3 years from initial date of
Permit coverage.
S6.D.6.a.vi
Prepare SWPPPs for material storage and heavy
equipment maintenance or storage yards.
Ongoing
New Secondary Permittees –
3 years from initial date of
Permit coverage.
S6.D.6.b
Obtain NPDES Permit coverage for all facilities
requiring an Industrial Stormwater General
Permit.
Upon initial date of Permit
coverage.
S6.D.6.d
Provide training for employees whose
construction, operations, or maintenance job
functions may impact…

Ditch Maintenance Matrix

Summary: Ditch Maintenance, Matrix of requirements

February 2019
Roadside Ditch Maintenance Matrix
Table 1. Routine Ditch Maintenance Strategies.
Strategy
Description
Condition
Ditch
Surface Type
Water Flow
Common Equipment and Material Needs
Considerations
References
Ditch Vegetation Management Strategies
Mowing
Cutting vegetation
to a reasonable
height to allow for
proper water flow
and aesthetics
Tall vegetation is
impeding flow of
water through the
ditch or causing line
of sight issues
 Vegetated
 No flow
• Mower
• Specialized mower for steep slopes
• Brooms, scoops, shovels, and/or
handheld blowers
Additional Equipment and Materials for
Natural Flow
• Reflective markers (“fish sticks”)
Considerations Prior to Implementation
• Set the mowing height at the highest acceptable level. For standard turf grass, mowing
only the top 1/3 of the grass blade height is recommended. Where vegetation growth is
excessive, additional mowing may be necessary.
• Avoid operating in wet areas or rough terrain to minimize scalping and rutting.
• Strategize mowing direction to minimize spreading of cut material onto adjacent paved
surfaces.
• If vegetation is providing flow control or treatment, too much removal or trimming could
reduce these functions.
• If possible, retain vegetation on the south or west sides of the ditch to provide shading of
the ditch and reduce water temperature.
• If there is an opportunity to re-seed, low growing grass seed mix is recommended to
reduce mowing frequency and cost.
Steep Slope Considerations
• Use a specialized mower when steep slopes (≥ 15 percent) are present.
Disposal Considerations
• Turf grass may be mulch mowed and left in place; however, large quantities of turf grass
clippings may lead to outlet clogging and nutrient loading in downstream water bodies.
Refer to Invasive Species
and Noxious Weed
Removal (Table 1, page 3)
for additional
recommendations
regarding mowing.
Refer to Fact Sheet F3 –
Maintaining Ditches that
Convey Natural Flow for
natural flow considerations.
Refer to local codes and
regulations for additional
requirements.
Brush Cutting
(or Brushing)
Trimming woody
vegetation to
remove overgrown
and/or excessive
vegetation to allow
for proper water
flow and to restore
sight distance
• Overgrown/
excessive
vegetation
impeding flow or
storage of water
and sediments
• Safety or
structural integrity
of the roadway is
jeopardized
 Vegetated
 No flow
• Brush cutters
• Power saws
• Axes and/or machetes
• Pruning shears, loppers, and/or clippers
• Brooms, scoops, shovels, and/or rakes
• Truck cover (for securing load during
transport)
Considerations Prior to Implementation
• If vegetation is providing flow control or treatment, too much removal or trimming could
reduce these functions.
• If possible, retain vegetation on the south or west sides of the ditch to provide shading of
the ditch and reduce water temperature.
Disposal Considerations
• Remove cut branches/other vegetative debris after brushing to reduce outlet clogging
and spreading invasive species.
• Compost or stockpile vegetative matter in a clean green stockpile at your maintenance
facility, if possible.
Refer to local codes and
regulations for additional
requirements.
February 2019
Roadside Ditch Maintenance Matrix
Table 1 (continued). Routine Ditch Maintenance Strategies.
Strategy
Description
Condition
Ditch
Surface Type
Water Flow
Common Equipment and Material Needs
Considerations
References
Ditch Vegetation Management Strategies (continued)
Minor
Reseeding/
Replanting
Adding seed and/or
plants to stabilize
exposed soils.
Applies to
conditions affecting
a small section of a
ditch that can be
addressed as part of
routine
maintenance.
• Sparse
vegetation/
eroded patches
on ditch bottom
• Poor grass growth
 Vegetated
 Bare Soil
 No flow
• Seed mix
• Hydroseeder
• Post-seeding erosion control BMPs (e.g.,
straw mulch, biodegradable nets and
blankets, coir mats)
Considerations Prior to Implementation
• Ensure that erosion control BMPs are installed properly to avoid blockages.
• Low growing grass seed mix is recommended to reduce mowing frequency and cost.
• Confirm that there are no weed seeds or invasive plant seeds in the seed mixes.
• Seed and/or plant during the following optimum windows:
o Late spring (April 1 through June 30)
o Early fall (September 1 through October 1)
• Establishment of vegetation may not be feasible in coarse grained or mineral soils.
When major reseeding/
replanting is necessary to
correct poor conditions,
refer to Major Replanting/
Reseeding(Table 2, page 9).
Refer to Fact Sheet F3 –
Maintaining Ditches that
Convey Natural Flow for
natural flow considerations.
Refer to local codes and
regulations for additional
requirements.
Weed
Control
Control of weeds
through biological,
physical,
mechanical,
chemical, or cultural
methods
Weeds present in
ditch
 Vegetated
 Bare Soil
 Rock
 No flow
 Standing
water
 Low flow
• Required permits (keep documentation
on-site during work)
• Weeding tools
• Weed burner
• Brooms, scoops, shovels, and/or rakes
Considerations Prior to Implementation
• Verify that required permits have been obtained prior to beginning work.
• Review preferred implementation strategies documented in an Integrated Pest
Management (IPM) plan.
• Ensure that herbicide applications are performed by licensed, qualified staff.
• Use physical and/or mechanical methods of vegetation removal rather than applying
herbicides, where practical.
Disposal Considerations
• Compost or stockpile vegetative matter in a clean green stockpile at your maintenance
facility, if possible, and only if invasive species and noxious weeds are not present.
Refer to Invasive Species
and Noxious Weed
Removal (Table 1, page 3)
for disposal considerations
when invasive species and
noxious weeds are present.
Refer to Fact Sheet F3 –
Maintaining Ditches that
Convey Natural Flow for
natural flow considerations.
Refer to Fact Sheet A3 –
Permit Requirements for
Ditch Maintenance for
permitting considerations.
Refer to your local IPM plan,
local codes and regulations
for additional requirements.
February 2019
Roadside Ditch Maintenance Matrix
Table 1 (continued). Routine Ditch Maintenance Strategies.
Strategy
Description
Condition
Ditch
Surface Type
Water Flow
Common Equipment and Material Needs
Considerations
References
Ditch Vegetation Management Strategies (continued)
Invasive
Species and
Noxious
Weed
Removal
Control of invasive
species and noxious
weeds through
biological, physical,
mechanical,
chemical, or cultural
methods
• Invasive species
present
• Noxious weeds
present
 Vegetated
 Bare Soil
 Rock
 No flow
 Standing
water
 Low flow
• Required permits (keep documentation
on-site during work)
• Weeding tools
• Weed wrench
• Targeted herbicide applicator (woody
painter/herbicide wand)
• Garbage bags (to prevent seed
development and dispersal)
• Protective clothing and eye protection
(for toxic, noxious weeds)
Considerations Prior to and During Implementation
• Verify that required permits have been obtained prior to beginning work.
• Invasive species may need to be removed by hand.
• Pull plants when soils are moist and before seeds are produced.
• Identify invasive species that can and should be controlled or reduced by mowing.
• Ensure that herbicide applications are performed by licensed, qualified staff.
• Prior to mowing, implement the following for small populations of invasive plants:
o Use herbicides early in the summer.
o Physically remove flower or seed heads (cut and bag).
o Physically remove rootstock (mechanically excavate).
• Implement the following for large, mature invasive plants:
o Control large purple loosestrife plant populations with biocontrol beetles (Hylobias
sp. or Galrucella sp.) prior to mowing.
o Mow plants prior to seed maturation, allow the plants to regrow to a height of 2 to
4 feet and then treat with foliar herbicide.
• If mowing occurs after seed maturation, hand clean the upper parts of the mowing
equipment with a brush or broom prior to moving to a new location.
Disposal Considerations
• Ensure proper disposal per the Washington State Noxious Weed Control Board.
• Bag cut flowers and seed heads.
Refer to Fact Sheet F3 –
Maintaining Ditches that
Convey Natural Flow for
natural flow considerations.
Refer to Fact Sheet A3 –
Permit Requirements for
Ditch Maintenance for
permitting considerations.
Refer to the Washington
State Noxious Weed
Control Board for weed
identification, removal, and
disposal considerations:
www.nwcb.wa.gov
Refer to your local IPM plan,
local codes and regulations
for additional requirements.
Other Maintenance Strategies
Inlet/Outlet
Cleaning
Clean accumulated
sediment from
inlets and outlets
Accumulated
sediment or blockage
impeding flow
(≥ 50% blockage) at
inlet/outlet pipe
 Vegetated
 Bare Soil
 Rock
 Paved
 Metal
 No flow
 Standing
water
• Rake, hoe, or shovel
• Wheelbarrow or buckets
Steep Slope Considerations
• Consider adjusting threshold to ≥ 30% blockage when steep slopes (≥ 15%) are present.
Disposal Considerations
• Use or disposal options for the sediment removed from the inlet and/or outlet will
depend on the characterization of the waste.
Refer to Fact Sheet A3 –
Permit Requirements for
Ditch Maintenance for
permitting considerations.
Refer to local codes and
regulations for additional
requirements.
February 2019
Roadside Ditch Maintenance Matrix
Table 1 (continued). Routine Ditch Maintenance Strategies.
Strategy
Description
Condition
Ditch
Surface Type
Water Flow
Common Equipment and Material Needs
Considerations
References
Other Maintenance Strategies (continued)
Nuisance
Animal/
Insect
Control
Control of nuisance
animals/insects
through mechanical,
manual, or chemical
methods. Examples
of nuisance animals
and insects include:
• Beavers: May
block ditch
capacity with
dams
• Bees: Could
pose a hazard to
crews
maintaining the
ditch
• Moles:
Contribute to
erosion by
burrowing holes
• Mosquitoes:
May result from
stagnant flow in
ditch; nuisance
and public health
hazard
• Nutria:
Contribute to
erosion by
destroying the
banks of ditches
Nuisance animals/
insects present
 Vegetated
 Bare Soil
 Rock
 Paved
 Metal
 No flow
 Standing
water
• Animal guards (e.g., rods, flap gates, and
finger-type flap gates) for outlet pipes
• Traps (if allowed)
Considerations Prior to Implementation
Preferred implementation strategies should be documented in an Integrated Pest
Management (IPM) plan.
Refer to Fact Sheet F3 –
Maintaining Ditches that
Convey Natural Flow for
natural flow considerations.
Refer to Fact Sheet A3 –
Permit Requirements for
Ditch Maintenance for
permitting considerations.
Refer to your local IPM plan,
local codes and regulations
for additional requirements.
February 2019
Roadside Ditch Maintenance Matrix
Table 2. Corrective Ditch Maintenance Strategies.
Strategy
Description
Condition
Ditch
Surface Type
Water Flow
Common Equipment and Material Needs
Considerations
References
Ditch Cleaning Strategies
Hand Ditching
Removing
sediment and
debris manually
using a rake,
hoe, or shovel
• Sediment
accumulation
near inlet and/or
outlet
• Excess sediment
impeding flow or
causing erosion
 Vegetated
 Bare Soil
 Rock
 Paved
 Metal
 No flow
 Low flow
• Rake, hoe, or shovel
• Wheelbarrow or buckets
• Erosion control BMPs (e.g., wattles, check dams, silt
fences)
Additional Equipment and Materials for Natural Flow
• Required permits (keep documentation on-site during
work)
• Containment dams (e.g., water bladders, sand bags)
• Vactor truck (for non -fish bearing waters and low -flow
scenarios)
• Fish exclusion nets (9.5 mm stretched mesh)
• Pump and bypass setup (if ditch flow is significant)
• Spill kit, including containment for the pump
• Erosion control BMPs for pump outfall, channel
stabilization, etc.
Considerations Prior to Implementation
• Verify that required permits have been obtained prior to beginning work.
• Cleaning should be performed during low flow or no flow periods if
possible.
• Install erosion control BMPs prior to conducting sediment removal.
• Consider retaining vegetation near ditch outlet(s), also known as “skip
ditching.”
• Reseed and install erosion control BMPs after sediment has been removed
if needed.
Steep Slope Considerations
• Retain additional vegetation near ditch outlet(s) when steep slopes (≥ 15
percent) are present.
Disposal Considerations
• Sweep and collect dirt and debris remaining on the pavement at the
completion of work.
• Separate screenings into soil and vegetative matter (e.g., leaves, grass,
needles, branches, etc.) categories:
o Compost or stockpile vegetative matter in a clean green stockpile at
your maintenance facility, if possible.
o Use or disposal options for the soil portion will depend on the
characterization of the waste.
Refer to Minor Reseeding/
Replanting (Table 1,
page 2).
Refer to Fact Sheet F2 –
Ditch Cleaning Strategies
for additional information
on ditch cleaning.
Refer to Fact Sheet F3 –
Maintaining Ditches that
Convey Natural Flow for
natural flow considerations.
Refer to Fact Sheet A3 –
Permit Requirements for
Ditch Maintenance for
permitting considerations.
Refer to local codes and
regulations for additional
requirements.
February 2019
Roadside Ditch Maintenance Matrix
Table 2 (continued). Corrective Ditch Maintenance Strategies.
Strategy
Description
Condition
Ditch
Surface Type
Water Flow
Common Equipment and Material Needs
Considerations
References
Ditch Cleaning Strategies (continued)
Bucket Ditching
(Mechanical
Excavation)
Removing
sediment and
debris in deep
ditches where
hand ditching is
impractical
• Sediment
accumulation
near inlet and/or
outlet
• Excess sediment
impeding flow or
causing erosion
 Vegetated
 Bare Soil
 No flow
 Low flow
• Backhoe or excavator with ditching bucket or Ditch
Master
• Erosion control BMPs (e.g., wattles, check dams, silt
fences)
Additional Equipment and Materials for Natural Flow
• Required permits (keep documentation on-site during
work)
• Containment dams (e.g., water bladders, sand bags)
• Vactor truck (for non -fish bearing waters and low -flow
scenarios)
• Fish exclusion nets (9.5 mm stretched mesh)
• Pump and bypass setup (if ditch flow is significant)
• Spill kit, including containment for the pump
• Erosion control BMPs for pump outfall, channel
stabilization, etc.
Considerations Prior to Implementation
• Verify that required permits have been obtained prior to beginning work.
• Cleaning should be performed during low flow or no flow periods if
possible.
• Cleaning should utilize low-impact equipment if feasible.
• Install erosion control BMPs prior to conducting sediment removal.
• Consider retaining vegetation near ditch outlet(s), also known as “skip
ditching.”
• Reseed and install erosion control BMPs after sediment has been removed
if needed.
• Keep excavation equipment on the roadway and off the ditch bank.
Steep Slope Considerations
• Retain additional vegetation near ditch outlet(s) when steep slopes (≥ 15
percent) are present.
Disposal Considerations

Field Guide to Roadside Ditch Maintenance

Summary: Field Guide to ditch maintenance, roadside ditches, field guide

ROADSIDE DITCH
MAINTENANCE IN
WESTERN WASHINGTON
FIELD GUIDE
February 7, 2019
Field Guide for Roadside Ditch Maintenance in Western Washington: Routine Maintenance
Ditch maintenance strategies fall into two categories: routine maintenance and corrective
maintenance. Some maintenance strategies can fall into both categories.
Different ditch types and different existing conditions require different
maintenance strategies, and appropriate maintenance strategies may
be limited by cost, space availability, and environmental regulations.
Some existing ditches may be so degraded that they require more
complicated and expensive source control or retrofit strategies.
This field guide focuses on the implementation of routine and
corrective maintenance strategies by municipal maintenance staff in
roadside ditches that convey stormwater.
Introduction
The reference bar at the bottom of most of the maintenance strategy pages refers to a set
of 8 fact sheets that were also developed as part of this project:
Fact Sheet A1 – Ditch Mapping
Recommendations
Fact Sheet A2 – Prioritizing Ditches for
Inspection and Maintenance
Fact Sheet A3 – Permit Requirements for
Ditch Maintenance
Fact Sheet A4 – Source Control Strategies
for Ditches
Fact Sheet A5 – Ditch Retrofit Strategies
Fact Sheet F1 – Considerations for Field
Evaluation of Roadside Ditches
Fact Sheet F2 – Ditch Cleaning Strategies
Fact Sheet F3 – Maintaining Ditches that
Convey Natural Flow
This guide is for reference only. All maintenance strategies must comply with local codes and regulations.
Maintenance strategies in ditches that convey natural flow require special considerations.
This field guide was developed by Herrera Environmental Consultants with input from King County and the
Regional Operations and Maintenance Program (ROADMAP). Project funding was provided by a National
Estuary Program grant from the Washington State Department of Ecology.
Fact sheets are boxed and shown in brighter text if they are directly applicable to the maintenance
strategy described on that page of the field guide.
Introduction
Field Guide for Roadside Ditch Maintenance in Western Washington: Routine Maintenance
What is ditch vegetation management?
Vegetation management includes the establishment and maintenance of healthy,
beneficial vegetation in ditches and the control of excess or unwanted vegetation.
Why is ditch vegetation management important?
Ditches are designed to transport water away from the roadway to prevent roadway
flooding. Vegetation can promote this essential ditch function, but can also inhibit
the capacity of a ditch to convey water. Vegetation can also capture pollutants from
stormwater runoff.
Routine maintenance strategies for vegetation management should ensure that vegetation
is healthy, but does not encroach on the adjacent roadway or cause ditch capacity issues.
Mowing (page 3)
Routine Maintenance
Weed Control
(page 6)
(page 8)
(page 9)
Invasive Species and
Noxious Weed Removal
(page 7)
Brush Cutting (or
Brushing)
(page 4)
Minor Reseeding/
Replanting
(page 5)
Ditch Vegetation
Management
Nuisance Animal/
Insect Control
Inlet/Outlet
Cleaning
Ditch Vegetation Management
In general, routine maintenance can be completed by municipal maintenance staff
without major analysis, engineering, or permits. Ideally, ditches that are in good
condition do not require corrective maintenance and can be maintained through
routine inspections and maintenance.
The routine maintenance strategies outlined in this field guide include:
Field Guide for Roadside Ditch Maintenance in Western Washington: Routine Maintenance
Ditch Vegetation Management Strategies
Mowing
Description
Cutting vegetation to a reasonable height to allow for proper water flow and aesthetics
Condition
Tall vegetation is impeding flow of water through the ditch or causing line of sight issues
Ditch Surface Types
Vegetated
Water Flow
No flow
Common Equipment
and Materials
Mower
Specialized mower for steep slopes
Brooms, scoops, shovels, and/or handheld blowers
Additional Equipment
and Materials for
Natural Flow
Reflective markers (“fish sticks”)
Considerations Prior to
Implementation
Set the mowing height at the highest acceptable level. For standard turf grass, mowing
only the top 1/3 of the grass blade height is recommended. Where vegetation growth is
excessive, additional mowing may be necessary.
Avoid operating mowers in wet areas or rough terrain to minimize scalping and rutting.
Strategize mowing direction to minimize spreading of cut material onto adjacent paved
surfaces.
If vegetation is providing flow control or treatment, too much removal or trimming
could reduce these functions.
If possible, retain vegetation on the south or west sides of the ditch to provide shading
of the ditch and reduce water temperature.
If there is an opportunity to re-seed, low growing grass seed mix is recommended to
reduce mowing frequency and cost.
Steep Slope
Considerations
Use a specialized mower when steep slopes (≥ 15 percent) are present.
Disposal
Considerations
Turf grass may be mulch mowed and left in place; however, large quantities of turf grass
clippings may lead to outlet clogging and nutrient loading in downstream water bodies.
Fact Sheet References
Additional References
Refer to Invasive Species and Noxious Weed
Removal (page 7) for additional recommendations
regarding mowing.
Refer to local codes and regulations for additional
requirements.
Photo source: King County
Field Guide for Roadside Ditch Maintenance in Western Washington: Routine Maintenance
Ditch Vegetation Management Strategies
Brush Cutting or “Brushing”
Description
Trimming woody vegetation to remove overgrown and/or excessive vegetation to allow for
proper water flow and to restore sight distance
Condition
Overgrown/ excessive vegetation impeding flow or storage of water and sediments
Safety or structural integrity of the roadway is jeopardized
Ditch Surface Types
Vegetated
Water Flow
No flow
Common Equipment
and Materials
Brush cutters
Power saws
Axes and/or machetes
Pruning shears, loppers, and/or clippers
Brooms, scoops, shovels, and/or rakes
Truck cover (for securing load during transport)
Considerations Prior
to Implementation
If vegetation is providing flow control or treatment, too much removal or trimming
could reduce these functions.
If possible, retain vegetation on the south or west sides of the ditch to provide
shading of the ditch and reduce water temperature.
Disposal
Considerations
Remove cut branches/other vegetative debris after brushing to reduce outlet
clogging and spreading invasive species.
Compost or stockpile vegetative matter in a clean green stockpile at your
maintenance facility, if possible.
Vegetation management demonstration
Photo source: Kitsap County
Additional References
Refer to local codes and regulations
for additional requirements.
Field Guide for Roadside Ditch Maintenance in Western Washington: Routine Maintenance
Ditch Vegetation Management Strategies
Minor Reseeding/Replanting
Description
Adding seed and/or plants to stabilize exposed soils. Applies to conditions affecting a small
section of a ditch that can be addressed as part of routine maintenance (see Additional
References below).
Condition
Sparse vegetation/ eroded patches on ditch bottom
Poor grass growth
Ditch Surface Types
Vegetated
Bare Soil
Water Flow
No flow
Common Equipment
and Materials
Seed mix
Hydroseeder
Post-seeding erosion control BMPs (e.g., straw mulch, biodegradable nets and
blankets, coir mats)
Considerations Prior
to Implementation
Ensure that erosion control BMPs are installed properly to avoid blockages.
Low growing grass seed mix is recommended to reduce mowing frequency and cost.
Confirm that there are no weed seeds or invasive plant seeds in the seed mixes.
Seed and/or plant during the following optimum windows:
Late spring (April 1 through June 30)
Early fall (September 1 through October 1)
Establishment of vegetation may not be feasible in coarse grained or mineral soils.
Fact Sheet References
Examples of sparse or absent vegetation that could be classified as poor (left),
moderate (center), and good (right) vegetation coverage.
Additional References
When major reseeding/replanting is
necessary to correct poor conditions, refer
to Major Reseeding/Replanting (page 16)
in the Corrective Maintenance section of
this field guide.
Refer to local codes and regulations for
additional requirements.
Field Guide for Roadside Ditch Maintenance in Western Washington: Routine Maintenance
Ditch Vegetation Management Strategies
Weed Control
Description
Control of weeds through biological, physical, mechanical, chemical, or cultural methods
Condition
Weeds are present in a ditch
Ditch Surface Types
Vegetated
Bare Soil
Rock
Water Flow
No flow
Standing water
Low flow
Common Equipment
and Materials
Required permits (keep documentation on-site during work)
Weeding tools
Weed burner
Brooms, scoops, shovels, and/or rakes
Considerations Prior
to Implementation
Verify that required permits have been obtained prior to beginning work.
Review preferred implementation strategies documented in an Integrated Pest
Management (IPM) plan.
Ensure that herbicide applications are performed by licensed, qualified staff.
Use physical and/or mechanical methods of vegetation removal rather than
applying herbicides, where practical.
Disposal Conditions
Compost or stockpile vegetative matter in a clean green stockpile at your maintenance
facility, if possible, and only if invasive species and noxious weeds are not present.
Fact Sheet References
Reed canarygrass, Photo source: WA State Noxious Weed
Control Board
Additional References
Refer to Invasive Species and Noxious Weed
Removal (page 7) for disposal considerations
when invasive species and noxious weeds are
present.
Refer to your local IPM plan, local codes and
regulations for additional requirements.
Field Guide for Roadside Ditch Maintenance in Western Washington: Routine Maintenance
Ditch Vegetation Management Strategies
Invasive Species and Noxious Weed Removal
Description
Control of invasive species and noxious weeds through biological, physical, mechanical,
chemical, or cultural methods
Condition
Invasive species present Noxious weeds present
Ditch Surface Types
Vegetated Bare Soil Rock
Water Flow
No flow Standing water Low flow
Common Equipment
and Materials
Required permits (keep documentation on-site during work)
Weeding tools
Weed wrench
Targeted herbicide applicator (woody painter/ herbicide wand)
Garbage bags (to prevent seed development and dispersal)
Protective clothing and eye protection (for toxic, noxious weeds)
Considerations Prior to
Implementation
Verify that required permits have been obtained prior to beginning work.
Invasive species may need to be removed by hand.
Pull plants when soils are moist and before seeds are produced.
Identify invasive species that can and should be controlled or reduced by mowing.
Ensure that herbicide applications are performed by licensed, qualified staff.
Prior to mowing, implement the following for small populations of invasive plants:
Use herbicides early in the summer.
Physically remove (cut) flower or seed heads.
Physically remove rootstock (mechanically excavate).
Implement the following for large, mature invasive plants:
Control large purple loosestrife plant populations with biocontrol beetles
(Hylobias sp. or Galrucella sp.) prior to mowing.
Mow plants prior to seed maturation, allow the plants to regrow to a height of 2 to
4 feet and then treat with foliar herbicide.
If mowing occurs after seed maturation, hand clean the upper parts of the mowing.
equipment with a brush or broom prior to moving to a new location.
Disposal Conditions
Ensure proper disposal per the Washington State Noxious Weed Control Board.
Bag cut flowers and seed heads.
Fact Sheet References
Common invasive species that thrive in ditches include reed canarygrass and
Himalayan blackberry. These species can make ditches difficult to access and
inspect and can reduce ditch flow capacity.
Additional References
Refer to the Washington State Noxious
Weed Control Board (www.nwcb.wa.gov) for
weed identification, removal, and disposal
considerations.
Refer to your local IPM plan, local codes and
regulations for additional requirements.
Field Guide for Roadside Ditch Maintenance in Western Washington: Routine Maintenance
Inlet/Outlet Cleaning
Description
Clean accumulated sediment and blockages from inlets and outlets
Condition
Accumulated sediment or blockage impeding flow (≥ 50% blockage) at inlet/outlet pipe
Ditch Surface Types
Vegetated Bare Soil Rock
Paved Metal
Water Flow
No flow Standing water
Common Equipment
and Materials
Rake, hoe, or shovel
Wheelbarrow or buckets
Steep Slope
Considerations
Consider adjusting threshold to ≥ 30% blockage when steep slopes (≥ 15 percent) are
present.
Disposal Conditions
Use or disposal options for the sediment removed from the inlet and/or outlet will depend
on the characterization of the waste (see Fact Sheet A3 – Permit Requirements for Ditch
Maintenance).
Fact Sheet References
Culvert outlet is partially buried in sediment (left). Inlet blocked by structure (right).
Additional References
Refer to local codes and regulations for
additional requirements.
Field Guide for Roadside Ditch Maintenance in Western Washington: Routine Maintenance
Nuisance Animal/Insect Control
Description
Control nuisance animals/insects through mechanical, manual, or chemical methods. Examples
of nuisance animals and insects include:
Beavers: May block ditch capacity with dams
Bees: Could pose a hazard to crews maintaining the ditch
Moles: Contribute to erosion by burrowing holes
Mosquitoes: May result from stagnant flow in ditch; nuisance and public health
hazard
Nutria: Contribute to erosion by destroying the banks of ditches
Condition
Nuisance animals/insects present
Ditch Surface Types
Vegetated
Bare Soil
Rock
Paved
Metal
Water Flow
No flow
Standing water
Common Equipment
and Materials
Animal guards (e.g., rods, flap gates, and finger-type flap gates) for outlet pipes
Traps (if allowed)
Considerations Prior
to Implementation
Preferred implementation strategies should be documented in an Integrated Pest
Management (IPM) plan.
Fact Sheet References
Evidence of moles in a roadside ditch.
Additional References
Refer to your local IPM plan, local codes and regulations
for additional requirements.
Field Guide for Roadside Ditch Maintenance in Western Washington: Corrective Maintenance
Corrective Maintenance
Corrective maintenance may require analysis, engineering, or permitting prior to implementation. The
corrective maintenance strategies outlined in this field guide include:
Trees of Concern
(page 17)
Ditch Cleaning
Minor Ditch Reshaping/
Regrading (page 15)
Ditch Stabilization
(page 14)
Major Replanting/
Reseeding (page 16)
Hand Ditching (page 11)
Bucket Ditching (page 12)
Shoulder Ditching (page 13)
Minor Inlet/Outlet Repair
(page18)
What is ditch cleaning?
Ditch cleaning is a…

Low Impact Development Training: Eastern Washington Bioretention Media

Summary: bioretention media physical and chemical characteristics,

INSTRUCTORS
Curtis Hinman
Senior Scientist
Key project experience: Research
specialist in the performance and
design of LID practices.
ADVANCED TOPICS IN LID DESIGN:
BIORETENTION MEDIA AND COMPOST
AMENDED SOILS
Training Program
Statewide LID
introduction
media primer
water quality treatment strategies
performance
AGENDA
wrap-up
LOGISTICS
SCHEDULE
8‐hour training
Lunch on your own
OTHER LOGISTICS
• Restrooms
• Food
• Turn off cell phones
• Sign in and sign out
LEARNING OBJECTIVES
1. Gain an advanced level understanding
of the physical and chemical
characteristics of bioretention media
components and blends necessary to
meet specific performance objectives.
2. Understand the flow control and water
quality treatment performance of
current bioretention media
specifications.
3. Know the options for meeting BMP
T5.13, and strategies for determining
site soil conditions and developing a soil
management plan.
PROGRAM OVERVIEW
• 2012: Public and private
partners engage state
legislature to fund program
• June 2012: LID Training
Steering Committee convened
• 2012‐2013: Washington State
LID Training Plan developed:
www.wastormwatercenter.org/
statewide‐lid‐training‐program‐
plan
• 2014: Training program built
from state LID Training Plan
PROGRAM OVERVIEW
• Implement first phase of
trainings (September 2014
through May 2015)
• 64 trainings offered in first
phase
• Three levels: Introductory,
Intermediate, and Advanced
PROJECT LEAD
ADDITIONAL TRAINING SUPPORT
TEAM
CORE TEAM
Introduction to
LID for Eastern
Washington
INTRODUCTORY
INTERMEDIATE
ADVANCED
TRAIN THE TRAINERS
Service Providers
Introduction to
LID for Inspection &
Maintenance Staff
Introduction to
LID for Developers &
Contractors: Make
Money be Green
Intermediate LID
Design: Rainwater
Collection Systems &
Vegetated Roofs
Intermediate LID –
NPDES Phase I & II
Requirements
Intermediate
LID Design:
Permeable Pavement
Intermediate
LID Design:
Hydrologic Modeling
Advanced Topics in
LID Design:
Bioretention
Advanced Topics in
LID Design:
Permeable Pavement
Advanced Topics in
LID Design:
Hydrologic Modeling
Advanced Topics in
LID Design: Site
Assessment, Planning
& Layout
LID Topic Experts
Advanced Topics in
LID Design: Rainwater
Collection Systems &
Vegetated Roofs
Advanced Topics in
LID Design:
Bioretention Media
TRAINING SEQUENCE
Advanced Topics for
LID Operations:
Bioretention
Intermediate
LID Design:
Bioretention
Advanced Topics for
LID Operations:
Permeable Pavement
Intermediate LID
Design: Site
Assessment, Planning
& Layout
Introduction to
LID for Eastern
Washington
INTRODUCTORY
INTERMEDIATE
ADVANCED
TRAIN THE TRAINERS
Service Providers
Introduction to
LID for Inspection &
Maintenance Staff
Introduction to
LID for Developers &
Contractors: Make
Money be Green
Intermediate LID
Design: Rainwater
Collection Systems &
Vegetated Roofs
Intermediate LID –
NPDES Phase I & II
Requirements
Intermediate
LID Design:
Permeable Pavement
Intermediate
LID Design:
Hydrologic Modeling
Advanced Topics in
LID Design:
Bioretention
Advanced Topics in
LID Design:
Permeable Pavement
Advanced Topics in
LID Design:
Hydrologic Modeling
Advanced Topics in
LID Design: Site
Assessment, Planning
& Layout
LID Topic Experts
Advanced Topics in
LID Design: Rainwater
Collection Systems &
Vegetated Roofs
Advanced Topics in
LID Design:
Bioretention Media
TRAINING SEQUENCE
Advanced Topics for
LID Operations:
Bioretention
Intermediate
LID Design:
Bioretention
Advanced Topics for
LID Operations:
Permeable Pavement
Intermediate LID
Design: Site
Assessment, Planning
& Layout
introduction
2002
• First bioretention applications with monitoring (Seattle SEA
Street).
• Primarily topsoil based media.
2009
• Issues with BSM consistency using topsoil emerge.
• PSAT funds small project through WSU to ID alternative and
potentially more consistent materials for BSM. Flow focused.
Sand‐ and compost‐based media guideline developed.
• Report guidelines adopted by Ecology for western WA
specification.
• Sand spec well‐tested and performs well hydraulically. OM
content spec too high.
2011
• WSU LID research facility comes online. Media blend research
focus (no funding to conduct fundamental media component
characterization).
In the beginning there wasn’t much…
2012
• Export of N, P and Cu identified at WSU facility and City of Redmond
swale monitoring.
• Individual BSM component characterization studies begin at Port of
Olympia (Herrera), City of Redmond (Herrera) and at WSU (primarily
compost).
2013
• Ecology funds approximately $1 million in media study projects through
Kitsap County (Herrera technical lead), City of Tacoma (UWT technical
lead) and City of Redmond (Herrera technical lead).
• Kitsap County project examining a broad range of individual media
components.
• City of Tacoma project focused on WTRs.
• Redmond focused on full‐scale monitoring of swales (component
characterization included).
2015
• Significant new data coming available to hopefully improve BSM
performance and consistency.
• We may be a few years from developing a reliable, affordable and non‐
proprietary BSM to treat a broad suite of pollutants.
BACKGROUND
INTRODUCTION
Today’s focus:
• Bioretention media for advanced water quality treatment
(direct release to receiving waters, over shallow drinking
water aquifers, industrial sites, remedial sites…)
• There are many applications where a conventional sand
and compost or topsoil‐based media will perform well
BACKGROUND
Context
• For advance treatment media we are opening a complex
black box…
• And attempting to reliably replicate a dynamic biological
system with complex structures and processes to treat a
broad range of contaminants to very low levels…a worthy
challenge!
INTRODUCTION
BACKGROUND
INTRODUCTION
• Flow Entrance
• Pre‐Settling
• Ponding Area
• Bioretention Soil
• Mulch/Compost
• Vegetation
• Filter Fabric (?)
• Liner (optional)
• Underdrain (optional)
• Overflow
media primer
BIORETENTION HYDRAULICS PRIMER
MEDIA BASICS
Factors influencing hydraulic conductivity
• Percent fines
• Particle size distribution
BIORETENTION HYDRAULICS PRIMER
MEDIA BASICS
Hydraulic conductivity strongly related to
percent fines (passing #200 sieve)
BIORETENTION HYDRAULICS PRIMER
MEDIA BASICS
Hydraulic conductivity strongly related to
coefficient of uniformity
BIORETENTION HYDRAULICS PRIMER
MEDIA BASICS
Factors influencing hydraulic conductivity
• Percent fines
• Particle size distribution
• Compaction
• Organic material
• Plants
BIORETENTION HYDRAULICS PRIMER
MEDIA BASICS
Control structures
BIORETENTION HYDRAULICS PRIMER
MEDIA BASICS
• ASTM D2434
Break
WATER QUALITY TREATMENT PRIMER
MEDIA BASICS
All primary pathways for removing pollutants from storm flows
are active in bioretention
• Stormwater volume reduction
• Sedimentation
• Filtration
• Phytoremediation
• Thermal attenuation
• Sorption
• Complexation
• Volatilzation
WATER QUALITY TREATMENT PRIMER
Factors influencing water quality treatment
• pH
• Temperature
• Hydraulic residence time
• Media (organic material, particle size, porosity, chemistry)
• Competing ions, ionic chemistry
• Soil water condition
• Influent concentration
MEDIA BASICS
WATER QUALITY TREATMENT PRIMER
Is the following statement correct?
• If an influent concentration of 5 µg/L into a bioretention area
results in an effluent concentration of 10 µg/L
then
• an influent concentration of 50 µg/L will result in an effluent
concentration of 100 µg/L.
MEDIA BASICS
WATER QUALITY TREATMENT PRIMER
Sorption
• Ionic charge and speciation
• Functional groups (moiety)
• Organic material (TOC and DOC)
• Competing ions and ion exchange
• Clay (particle size)
Metal Fraction
Mobility
Exchangeable Fraction
High. Changes in major cationic compositions may cause
release due to ion exchange
Fe‐Mn Oxides Bound
Carbonate Bound
Medium. Changes in redox conditions may cause release
OM Bound
Medium/high. Decomposition/oxidation with time.
Residual Fraction
Low. Available after weathering.
MEDIA BASICS
WATER QUALITY TREATMENT PRIMER
Sorption
MEDIA BASICS
water quality treatment strategies
TREATMENT STRATEGIES
• Sorption and metal complexes
• Metal atom associated with group of molecules or anions
• Organically bound Cu often dominant fraction in soils
“Cu however, has a high
affinity for soluble organic
ligands and the formation of
these complexes may greatly
increase Cu mobility in soils.”
(EPA 1992)
MEDIA BASICS
TREATMENT STRATEGIES
• Implications for copper
• To best manage Cu we will likely have to manage DOC
• Fe and Ca may be (likely), important for DOC capture
• Identify aggregate and organic materials with low Cu content
and flushing potential
MEDIA BASICS
TREATMENT STRATEGIES
• Primary mechanisms for P
management
• Plant and microbial uptake
• Sorption and precipitation.
Sorption materials include
Al and Fe hydroxides and
• Reactions are pH
dependent. Calcium likely
not a reliable material for
binding P (higher pH best
for precipitation)
MEDIA BASICS
Organic matter, fertilizers
Available P
Mineral P
Adsorbed P
inorganic
Microbial P
organic
leaching
weathering
precipitation
Plant uptake
Methods for retaining phosphate
TREATMENT STRATEGIES
MEDIA BASICS
TREATMENT STRATEGIES
• P removal efficiency v input concentration
MEDIA BASICS
‐300
‐250
‐200
‐150
‐100
‐50
100
0.1
0.2
0.3
0.4
0.5
0.6
Phosphorus Removal
Efficiency,%
Concentration, mgTP/L
BIN 34
BIN 35
BIN 36
BIN 37
During initial loadings with tap water (< 0.06mg/l) there was export of P.
Stormwater loadings commenced after 18 months.
TREATMENT STRATEGIES
Implications for phosphorus
• Design with lower organic material content and upper range
for C/N ratio (i.e. 35/1)
• Use organic material that is refractory (probably the older
the better)
• Bind P with Al or Fe hydroxides
• Identify aggregate material with little to no P flushing
• Likely will need a polishing layer/filter if using compost
• Above design considerations likely most important for at
least three years of installation
MEDIA BASICS
TREATMENT STRATEGIES
Methods for managing nitrate (biological transformations)
MEDIA BASICS
organic matter
mineralization
Ammonium (NH4
nitrification
Nitrites (NO2
Nitrates (NO3
plant consumption
Denitrification
(N2, N2O)
leaching
NO3‐ electron acceptor not O2 in
anaerobic conditions
2NO3‐ + 10e‐ + 12H+ N2 + 6H2O
Electron donor may be sugar,
hydrocarbon (simple) or complex
(mulch).
TREATMENT STRATEGIES
MEDIA BASICS
TREATMENT STRATEGIES
Methods for managing nitrate (60‐15‐15‐10 columns)
MEDIA BASICS
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
12/14/11 Test
12/21/11 Test
12/28/11 Test
1/3/12 Test
Concentration (mg/L)
Influent
Treatment 1
Treatment 2
Treatment 3
Treatment 4
TREATMENT STRATEGIES
Implications
• Design with an elevated under‐drain (multiple advantages to
this approach)
• Caution: we don’t fully understand the potential for metal
and P desorption in the anoxic zone
MEDIA BASICS
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
12/14/11 Test
12/21/11 Test
12/28/11 Test
1/3/12 Test
Concentration (mg/L)
Influent
Treatment 1
Treatment 2
Treatment 3
Treatment 4
TREATMENT STRATEGIES
PERFORMANCE
Nitrate‐nitrite (mg/L)
10/16/2014
influent
70vs/20cp/10gac
70ws/20cp/10ash
70vs/20cp/10ash
90vs/10comp/player
1.75
0.028
0.327
0.362
1.62
0.028
0.083
0.339
1.53
0.037
0.194
0.366
1.57
0.031
0.201
0.356
1.573
0.028
0.194
0.362
1.570
10/30/2014
influent
70vs/20cp/10gac
70ws/20cp/10ash
70vs/20cp/10ash
90vs/10comp/player
0.561
0.016
0.216
no sample
0.842
0.019
0.097
0.201
0.851
0.025
0.164
0.198
0.88
0.020
0.159
0.200
0.858
0.019
0.164
0.200
0.851
‐52
TREATMENT STRATEGIES
Filtration: 60/40 bioretention media provides excellent filtration
of TSS (depending on PSD and permeability)…
MEDIA BASICS
Does not appear to be concentration dependent
performance
HYDRAULIC PERFORMANCE
ASTM D2434 tests performed 2011 as part of a project to
standardize test methods across regional labs (60/40 media)
PERFORMANCE
HYDRAULIC PERFORMANCE
• Soil treatments
• 60% sand – 40% compost
• 80% sand – 20% compost
• 60% sand – 30% compost –
10% WTRs
• 60%sand – 15% compost –
15% shredded bark – 10%
WTRs
• 60% sand – 10% biosolids –
15% – shredded bark – 5%
sawdust – 10% WTRs
PERFORMANCE
HYDRAULIC PERFORMANCE
• Mesocosm Falling Head Permeability Test (May‐June 2011)
0.00
5.00
10.00
15.00
20.00
25.00
30.00
35.00
Ksat (in/hr)
Mesocosm
12″ ‐ 6″
6″ ‐ 0″
PERFORMANCE
HYDRAULIC PERFORMANCE
• Mesocosm Falling Head Permeability Test (June 2012)
0.00
5.00
10.00
15.00
20.00
25.00
30.00
35.00
Ksat (in/hr)
Mesocosm
12″ ‐ 6″
6″ ‐ 0″
PERFORMANCE
HYDRAULIC PERFORMANCE
• Mesocosm Falling Head Permeability Test (June 2013)
0.00
10.00
20.00
30.00
40.00
50.00
Ksat (in/hr)
Mesocosm
12″ ‐ 6″
6″ ‐ 0″
PERFORMANCE
HYDRAULIC PERFORMANCE
ASTM D2434 tests performed 2015 as part of a project to develop a
high performance water quality treatment media
PERFORMANCE
138
148
100
120
140
160
70vs/20fe/10de
70vs/20fe/10ash
70vs/20cp/10de
70vs/20cp/10gac
70ws/20cp/10ash
70vs/20cp/10ash
90vs/10comp/player
Ksat (in/hr)
Treatment
Mean Ksat Rates per ASTM 2434
HYDRAULIC PERFORMANCE
Implications
• Consider carefully acceptance/verification
requirements….the system may be hydraulically functional,
but not meet specific guidelines at that time
• Consider how to size and operate a system that may be
evolving over time
Side note
• The region may becoming more accepting of high flow media
with control structures
PERFORMANCE
Lunch
HYDRAULIC PERFORMANCE
Compost‐based media
PERFORMANCE
WATER QUALITY TREATMENT PERFORMANCE
PERFORMANCE
WATER QUALITY TREATMENT PERFORMANCE
PERFORMANCE
anything interesting
WATER QUALITY TREATMENT PERFORMANCE
PERFORMANCE
WATER QUALITY TREATMENT PERFORMANCE
PERFORMANCE
WATER QUALITY TREATMENT PERFORMANCE
PERFORMANCE
WATER QUALITY TREATMENT PERFORMANCE
PERFORMANCE
WATER QUALITY TREATMENT PERFORMANCE
PERFORMANCE
WATER QUALITY TREATMENT PERFORMANCE
PERFORMANCE
WATER QUALITY TREATMENT PERFORMANCE
PERFORMANCE
WATER QUALITY TREATMENT PERFORMANCE
PERFORMANCE
Analyte
Units
Median
Influent
Min
Median
Effluent
Max
Sand
Result
TSS
mg/L
4.9
5.3
22.5
Diss Zn
µg/L
20.0
Diss Cu
µg/L
1.7
8.6
15.9
14.0
PO4
mg/L
0.016
0.086
0.236
0.461
0.15
NO3‐NO2
mg/L
0.361
0.05
0.145
1.03
0.36
Fecal coliform CFU/100mL
229
22.5
• All mesocosms (Phase 1 flushing regime)
WATER QUALITY TREATMENT PERFORMANCE
PERFORMANCE
Developing a high‐performance WQ treatment media
WATER QUALITY TREATMENT PERFORMANCE
PERFORMANCE
WATER QUALITY TREATMENT PERFORMANCE
PERFORMANCE
Media treatments
• 60% sand/40% compost (control).
• 70% volcanic sand/20% iron‐fused wood chips/10% high carbon wood ash.
• 70% volcanic sand/20% iron‐fused wood chips/10% diatomaceous earth.
• 70% volcanic sand/20% coco coir/10% diatomaceous earth.
• 70% volcanic sand/20% coco coir/10% granulated activated charcoal.
• 70% washed sand/20% coco coir/10% high carbon wood ash.
• 70% volcanic sand/20% coco coir/10% high carbon wood ash.
• 90% volcanic sand/10% compost/polishing drainage layer (volcanic sand,
activated alumina and bone char).
WATER QUALITY TREATMENT PERFORMANCE
PERFORMANCE
WATER QUALITY TREATMENT…