OVERVIEW OF PROGRAM
• 2012: Direction and resources
from the state legislature
• June 2012: LID Training
Steering Committee
• 2012‐2013: Surveys to identify
training needs and service
providers
• Washington State LID Training
Plan (June 2013):
www.wastormwatercenter.org/
statewide‐lid‐training‐program‐
plan
PROJECT LEAD
ADDITIONAL TRAINING SUPPORT
OVERVIEW OF PROGRAM
CORE TEAM
OVERVIEW OF PROGRAM
• Implementation of first
round of trainings
(September 2014 through
May 2015)
• Three levels:
Introductory,
Intermediate, and
Advanced
• Train the Trainer program
for service providers and
LID topic experts
Hazel’s Creek City of Spokane
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
Topics: NPDES Phase
I & II Requirements
Intermediate
LID Design:
Permeable Pavement
Intermediate
LID Design:
Hydrologic Modelling
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
OVERVIEW OF PROGRAM
Advanced Topics for
LID Operations:
Bioretention
Intermediate
LID Design:
Bioretention
Advanced Topics for
LID Operations:
Permeable Pavement
Intermediate LID
Design: Site
Assessment, Planning
& Layout
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
Topics: NPDES Phase
I & II Requirements
Intermediate
LID Design:
Permeable Pavement
Intermediate
LID Design:
Hydrologic Modelling
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
TODAY’S TRAINING
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
3.2
INTRODUCTION TO LID
EASTERN WASHINGTON
Training Program
Statewide LID
INSTRUCTORS
GRETCHEN MULLER
Senior Associate
Key project experience: Facilitation,
curriculum development, education
and outreach, research and
evaluation
DUSTIN ATCHISON, PE
Water Resources Project Manager
Key project experience: LID design, stormwater
master planning, stream and wetland restoration
design, hydrologic and hydraulic modeling
introduction
AGENDA
regulatory & Eastern WA overview
purpose and principles of LID
BMP specifics
wrap up
introduction
LEARNING OBJECTIVES
1. Understand basic LID principles and practices.
2. General knowledge of on‐the‐ground LID
practices applicable to Eastern Washington,
common approaches and procedures for
design, installation, operations, maintenance,
and inspection.
3. Understand the current permit requirements
for encouraging and implementing LID.
4. Know where to find resources to help further
advance understanding of LID, as well as how
this course is nested in the larger LID training
program in Washington State.
LOGISTICS
SCHEDULE
• 4‐hour training with one
break
OTHER LOGISTICS
• Restroom location
• Food
• Turn off cell phones
• Q&A at end of each section
regulatory & Eastern WA overview
• Department of Ecology
• NPDES Municipal SW
Permit (Eastern WA)
• Flow control &
treatment performance
standards
• LID requirements
• Other Standards
• Combined Sewer
Overflow limits
• Local Jurisdictions
REGULATORY REQUIREMENTS
REGULATORY AND EASTERN WA OVERVIEW
REGULATORY REQUIREMENTS
REGULATORY AND EASTERN WA OVERVIEW
Permit
Overview
Clean Water Act (1972)
Fishable, swimmable waters, prevent
release of toxics
NPDES Permit
National Pollutant Discharge
Elimination System
Four main categories of NPDES
permits
Municipal, Construction, Industrial,
Boatyards
Permit Authority
Delegated to the Washington State
Department of Ecology by EPA
NPDES PERMIT REQUIREMENTS
REGULATORY AND EASTERN WA OVERVIEW
• Phase I*
• Populations ≥ 100,000
• Phase II
• Generally populations >
10,000
• Issuance date: August 1, 2012
• Effective date: August 1, 2014
• Permit term: 5 years (through
July 31, 2019)
*No Phase I jurisdictions in Eastern WA
NPDES PERMIT REQUIREMENTS
REGULATORY AND EASTERN WA OVERVIEW
Phase II Cities
Phase II Counties
Asotin
Clarkston
East Wenatchee
Ellensburg
Kennewick
Moses Lake
Pasco
Pullman
Richland
Selah
Spokane
Spokane Valley
Sunnyside
Union Gap
Walla Walla
Wenatchee
West Richland
Yakima
Asotin
Chelan
Douglas
Spokane
Walla Walla
Yakima
NPDES PERMIT REQUIREMENTS:
Core Elements
REGULATORY AND EASTERN WA OVERVIEW
Preparation of Stormwater Site
Plans
Construction Stormwater
Pollution Prevention
Source Control of Pollution
Preservation of Natural Drainage
Systems
Runoff Treatment
Flow Control
Operation and Maintenance
Local Requirements
NPDES PERMIT REQUIREMENTS:
Core Elements (CE)
INTRODUCTION & REGULATIONS
• CE #5 – Runoff Treatment
• Water quality treatment
for pollution‐generating
areas
• CE #6 – Flow Control
• Control of flow peaks and
flow durations
CORE ELEMENT # 5 (RUNOFF TREATMENT)
REGULATORY AND EASTERN WA OVERVIEW
• New development with
≥ 5,000 sf of pollution‐
generating impervious
surfaces (PGIS)
• Redevelopment with ≥
5,000 sf of PGIS for
specific industrial,
commercial, high‐use,
and high traffic sites
CORE ELEMENT # 5 (RUNOFF TREATMENT)
REGULATORY AND EASTERN WA OVERVIEW
• Standards
• Treat 90% of annual
runoff
• Specific treatment
required depending
on site type and/or
location:
• Basic (TSS)
• Metals (dissolved
Cu and Zn)
• Phosphorus
• Oil
CORE ELEMENT # 5 (RUNOFF TREATMENT)
REGULATORY AND EASTERN WA OVERVIEW
• Basic Treatment Exemptions
• Satisfies full dispersion
• Discharges to a qualified UIC
facility
• Metals Treatment Exemptions
• Discharges to non‐fish‐bearing
streams
• Direct discharges to the main
channels of certain rivers and lakes
• Subsurface discharges
• Restricted residential and
employee‐only parking areas
CORE ELEMENT # 6 (FLOW CONTROL)
REGULATORY AND EASTERN WA OVERVIEW
• New development with
≥ 10,000 sf of new
impervious surfaces
• Not required for
redevelopment unless
required under a basin plan
or other federal, state, or
local requirement
CORE ELEMENT # 6 (FLOW CONTROL)
REGULATORY AND EASTERN WA OVERVIEW
• Standard
• Based on a pre‐developed
condition (prior to
settlement) or existing
condition
CORE ELEMENT # 6 (FLOW CONTROL)
REGULATORY AND EASTERN WA OVERVIEW
• Exemptions
• Disperse total 25‐year
runoff volume without
discharge
• Discharge to irrigation
return flow stream reaches
• Direct discharge to flow
control “exempt surface
waters” (Large rivers &
streams, lakes & reservoirs
with > 100 sq. mi. drainage
area, reservoirs with outlet
controls)
Tom Campbell
CORE ELEMENT # 6 (FLOW CONTROL)
REGULATORY AND EASTERN WA OVERVIEW
• Exemptions
• Discharge to a
wetland with no
surface water outlet
• Discharge to a
stream that flows
only during runoff
producing event
Tom Campbell
NPDES PERMIT REQUIREMENTS: LID
REGULATORY AND EASTERN WA OVERVIEW
New development and redevelopment
Permittees shall allow nonstructural
preventive actions and source
reduction approaches such as:
• LID techniques
• Measures to minimize the
creation of impervious surfaces
• Measures to minimize the
disturbance of native soils and
vegetation
NPDES PERMIT REQUIREMENTS: LID
REGULATORY AND EASTERN WA OVERVIEW
• Some Eastern WA jurisdictions already
require stormwater to be retained onsite
• A majority of Eastern WA permittees
have adopted ordinances that meet or
closely approximate the EPA LID
standard
• LID projects funded by Ecology grants
have heightened interest in advancing
LID for Eastern WA
OTHER STANDARDS
REGULATORY AND EASTERN WA OVERVIEW
• Combined Sewer Overflow
Limits
• Local Jurisdictions
• CSO reduction efforts
• Conveyance capacity
City of Spokane
HYDROLOGY AND CLIMATE: Regions
REGULATORY AND EASTERN WA OVERVIEW
HYDROLOGY AND CLIMATE: Precipitation
REGULATORY AND EASTERN WA OVERVIEW
• 6 ‐ >60 in/year
• Most regions semi‐arid
or arid
HYDROLOGY AND CLIMATE: Snowfall
REGULATORY AND EASTERN WA OVERVIEW
Location
Average Annual Snowfall (inches)
Asotin
14.5
Ellensburg
27.7
Kennewick
6.9
Pullman
28.1
Richland
8.5
Spokane
41.4
Walla Walla
17.4
Wenatchee
27.6
Yakima
24.1
NATIVE VEGETATION
REGULATORY AND EASTERN WA OVERVIEW
• Prairie
• Pine forests
• Shrub‐Steppe
• Channeled scabland
• Dry & irrigated agricultural land
SOILS
REGULATORY AND EASTERN WA OVERVIEW
SIMILAR CLIMATES: Snowfall
REGULATORY AND EASTERN WA OVERVIEW
Source: CWP BMP Design Supplement for Cold Climates
SIMILAR CLIMATES: Temperature
REGULATORY AND EASTERN WA OVERVIEW
Source: CWP BMP Design Supplement for Cold Climates
SIMILAR CLIMATES: Growing Season
REGULATORY AND EASTERN WA OVERVIEW
Source: CWP BMP Design Supplement for Cold Climates
purpose and principles
WHAT IS LOW IMPACT DEVELOPMENT?
PURPOSE AND PRINCIPLES
• A land use development
strategy that emphasizes
protection and use of on‐site
natural features to manage
stormwater
• Integrates engineered, small
scale stormwater controls into
the site design
WHAT IS LOW IMPACT DEVELOPMENT?
PURPOSE AND PRINCIPLES
• Used at the parcel and
subdivision scale. Site scale
necessary but not sufficient.
Regional land use planning
critical for effective
stormwater management
• Primary goal: no measurable
impacts to receiving waters
by maintaining or
approximating pre‐
development surface flow
volumes and durations
PREDEVELOPED CONDITION
PURPOSE AND PRINCIPLES
Yakima Regional LID Stormwater Design Manual (April 2011)
DEVELOPED CONDITION
Yakima Regional LID Stormwater Design Manual (April 2011)
PURPOSE AND PRINCIPLES
PRINCIPLES: LID Objectives
PURPOSE AND PRINCIPLES
• Reduce the development
envelope
• Reduce impervious surfaces
• Protect and restore native
soils/vegetation
• Manage stormwater as close to
its origin as possible
• Reduce concentrated surface
flow, minimize stormwater
contact with impervious surfaces,
and increase stormwater contact
with soils and vegetation
PURPOSE: LID BMPs
PURPOSE AND PRINCIPLES
BMP
Flow Control
Treatment
Soil Amendment
Dispersion
Retaining & Planting Trees
Bioretention
Bioretention (underdrain)
X *
Permeable Pavement
X *
Green Roofs
Rainwater Harvesting
PRINCIPLES: LID BMPs
PURPOSE AND PRINCIPLES
• Infiltration
• Filtration
• Storage
• Evaporation
• Transpiration
Replace pre‐developed
hydrologic functions
City of Spokane
PRINCIPLES: Conventional vs. LID
PURPOSE AND PRINCIPLES
Convey runoff quickly to:
• End‐of‐pipe large‐scale
infiltration (e.g., infiltration
basins)
• Small‐scale subsurface
infiltration (e.g., dry wells)
LID BMPs
Aimee Navickis-Brasch
Conventional
Aimee Navickis-Brasch
Small‐scale surface infiltration
(e.g., bioretention swales)
Dispersion & vegetated filter
strips
Q&A
BMP specifics
AMENDED SOILS: Definition
BMP SPECIFICS
• Soil/landscape system with adequate
depth, permeability, and organic
matter
• Retains native soil functionality in a
post‐development landscape
• Builds soil structure,
moisture‐holding capacity
• Increases surface porosity
• Biofiltration of urban
pollutants
• Reuses “wastes” (yard waste,
manure, biosolids,
construction, land clearing
waste)
• Reduces summer irrigation
needs
AMENDED SOILS: Benefits
BMP SPECIFICS
Soils for Salmon
• Improves fertility & plant
vigor:
• Reduces need for
fertilizers and pesticides
• Reduces maintenance
costs
• Increases regrowth of
protective canopy
AMENDED SOILS: Benefits
BMP SPECIFICS
Soils for Salmon
UW Stormwater Trials
Glacial till soil typical in developing areas. High
runoff, and poor turf quality.
Same soil with 30% compost added. Up to 50% less
runoff, and turf is still healthier 4 years later.
• All pervious areas
• Incorporated into designs for
dispersion BMPs
AMENDED SOILS: Applications
BMP SPECIFICS
Parameter
Design Goal
Organic matter content (non‐turf)
6 to 8%
Organic matter content (turf)
3 to 5%
6.0 to 8.0
www.specmeters.com
• Not applicable to till soils
with slopes greater than 33%
• Imported topsoils should not
have an excessive percent of
clay fines
AMENDED SOILS: Limitations
BMP SPECIFICS
Option 1: Leave native vegetation and soil undisturbed, and protect
from compaction during construction.
AMENDED SOILS: Design Considerations
BMP SPECIFICS
Option 2: Amend existing site
topsoil or subsoil with
compost to meet the soil
organic matter requirements:
• Till 3” of compost in to
an 8” depth for
planting beds
• Till 1.75” of compost in
to an 8” depth for turf
• Scarify subsoil to a 12”
depth
AMENDED SOILS: Design Considerations
BMP SPECIFICS
www.buildingsoil.org
Option 3: Stockpile existing topsoil during grading, and replace 8” of
topsoil before planting:
• Amend if needed to meet the organic matter requirement
• Scarify subsoil to a 12” depth
AMENDED SOILS: Design Considerations
BMP SPECIFICS
Option 4: Import a topsoil
mix that meets the organic
content and depth
requirements:
• Scarify subsoil to a
12” depth or till in
some of the topsoil
AMENDED SOILS: Design Considerations
BMP SPECIFICS
Q&A
www.agriscapesoils.com
DISPERSION: Definition and Types
BMP SPECIFICS
• Vegetated areas that collect runoff
from impervious surfaces
• Restores the natural drainage patterns
of sheet flow and infiltration
• Types:
• Concentrated flow dispersion
• Sheet flow dispersion
• Full dispersion
• Steep impervious surfaces
• Driveways, sport courts, patios,
and roofs without gutters
• Single‐family residential and
rural development applications
• Spreads flows through a
vegetated pervious area
• Reduces peak flows
• Some water quality benefits
DISPERSION: Concentrated Flow
BMP SPECIFICS
Meadow at the Hylebos
• Flat or moderately sloping (<15%
slope) impervious surfaces
• Flows are already dispersed
• Vegetated flow path < 8% slope*
• Narrow band of vegetation for
attenuation and treatment
• Driveways, sport courts,
patios, and roofs without
gutters
DISPERSION: Sheet Flow
BMP SPECIFICS
Eastern WA LID Manual
SR 231 – Aimee S. Navickis-Brasch
• Up to 10% of impervious area can
be treated
• Can avoid triggering a flow control
facility by leaving natural
vegetation onsite
• Primarily for new development
• Commercial and residential
applications
DISPERSION: Full
BMP SPECIFICS
• Restores natural drainage
patterns of sheet flow and
infiltration
• Cost‐effective when sufficient
space is available (e.g., large
lots, rural short plats)
• Limited…