A Watershed Approach to Decentralized Wastewater Management

A Watershed Approach to Decentralized Wastewater Management

Need for a watershed approach

• Single-focus approaches limit the range of possibilities

• Many current water quality problems are from non-point sources (includes onsites)

• Land use/cover/management and wastewater/stormwater management are key issues

• Lack of integrated planning = poor results + wasted $$

Context for planning & management

• We have problems– Polluted waters– Organizational disconnects– Diffused authority– Few resources

• We have solutions– Interested people– Improving science & technology– Better assessment & other tools

Statutory and regulatory context

• Clean Water Act– Water quality standards– NPDES discharge permits– Stream & wetland “filling”

• Safe Drinking Water Act– Class V (large capacity systems)– Source water protection

• Public health codes– Residential wastewater

• Local Codes– Planning/zoning, subdivision, etc.

Source Water Protection Map for Slate Creek (Montgomery County

KY)

Clean Water Act Part I: Technology Based

NPDES Highlights• Point Source: Any discernable, confined,

discrete conveyance, including pipes and ditches

• Pollutant: Chemical wastes, biological materials, sewage, etc.

• Waters of the US: Interstate waters & wetlands, waters used in interstate & foreign commerce, and their tributaries & adjacent wetlands; the seas at high tide

Clean Water Act Part II:Water Quality Standards

•What are you using it for?

•What criteria support that use?

•How will you keep it from degrading?

WQS: development and implementation process

• WQS established by states and tribes; USEPA must review/approve prior to becoming effective

• If USEPA disapproves a state or tribe WQS and state or tribe doesn't revise it, USEPA promulgates a WQS

• Public review and comment at state, tribe, and federal levels

Recreational Uses– Primary contact (swimming)– Secondary contact (boating, etc.

Drinking water supply uses

– Filtered/unfiltered

Warmwater/coldwater aquatic life uses

WQS: Water Quality Criteria (WQC)

• Consistent scientifically with protecting all designated uses (DUs)

• Basic types of criteria– Narrative/numeric– Water column/sediment/ fish tissue

• Categories of criteria– Aquatic life

• Pollutant-specific/aquatic community indices– Human health (drinking/fish consumption)– Wildlife (semiaquatic/food chain effects)

Parameter Value Units

Dissolved Oxygen >5.0 milligrams/liter

pH 6-9 Standard Units

Un-ionized Amonia-N

<0.05 mg/l

Fecal Coliform <400 Colonies/100ml

Temp <25 Degrees C

Example: Numeric criteria for warmwater aquatic habitat

WQS: antidegradation provisions

• Purpose: Prevent deterioration of existing levels of good water quality

• States must have antideg policy & an implementation procedure

• Three tiers of protection– Tier 1: must maintain water quality criteria– Tier 2: must justify lowering WQ – Tier 3: outstanding waters cannot be

degraded

Identifying water quality problems

• Ongoing state monitoring to determine if WQSs are being met (Sec. 305b)

• Waters that are impaired or threatened are placed on the 303(d) list

• TMDLs must be developed for problem parameters

• TMDLs ID sources & propose needed pollutant reductions

Leading causes & sources of impairment

• Causes– Siltation (sediment)– Nutrients– Pathogens (bacteria)– Oxygen-depleting

substances– Pesticides

• Sources– Agriculture– Municipal point sources– Hydromodification– Habitat modification– Resource extraction– Urban runoff / storm

sewers

Addressing Water Quality

Issues via a Watershed Approach

EPA’s New Watershed Planning Handbook

http://www.epa.gov/owow/nps/watershed_handbook/

WatershedsWatersheds Subwatershed(14-digit HUC

or small urban

drainage)

Watershed(11-digit HUC; may

vary)

River Basin

07 07

01010202

0303

0404

05050606

A watershed approach helps to...A watershed approach helps to...

2. Facilitate Communication

and Partnerships3. Provide Means of

Cost-Effective Management

1. Encourage Sound Science

4. Focus on Environmental

Results

Watershed Mgmt. Plans

Point Source IssuesNonpoint Source Issues

TMDLs & Implementation PlansSource Water Protection PlansWater Resource Dev./Supply

PlansAnimal Feeding OperationsErosion & Sediment Control

Channel & Lake Restoration PlansCoastal Mgmt / Nat’l Estuary

ProgramDecentralized Wastewater Mgmt

Plans

Ag/Range Management PlansForest/Fisheries Management

PlansFloodplain, Parks, Planning &

Zoning

POTW 208 & CSO/SSO PlansStormwater Permit Activities

Watershed Planning Steps

STEP 1BUILD PARTNERSHIPS–ID stakeholders–ID issues of concern–Set preliminary goals–Develop indicators–Conduct outreach

Watershed Planning Steps

STEP 1BUILD PARTNERSHIPS

–ID stakeholders–ID issues of concern–Set preliminary goals–Develop indicators–Conduct outreach

STEP 2CHARACTERIZE WATERSHED

–Gather existing data–Create data inventory–ID data gaps–Collect additional data, if needed–Analyze data–ID causes and sources–Estimate pollutant loads

Watershed Planning Steps

STEP 1BUILD PARTNERSHIPS

–ID stakeholders–ID issues of concern–Set preliminary goals–Develop indicators–Conduct outreach

STEP 2CHARACTERIZE WATERSHED

–Gather existing data–Create data inventory–ID data gaps–Collect additional data, if needed–Analyze data–ID causes and sources–Estimate pollutant loads

STEP 3FINALIZE GOALS AND IDENTIFY SOLUTIONS

–Set goals and management objectives–Develop indicators/targets–Determine load reductions needed–ID critical areas–ID management measures needed

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Watershed Planning Steps

STEP 1BUILD PARTNERSHIPS

–ID stakeholders–ID issues of concern–Set preliminary goals–Develop indicators–Conduct outreach

STEP 2CHARACTERIZE WATERSHED

–Gather existing data–Create data inventory–ID data gaps–Collect additional data, if needed–Analyze data–ID causes and sources–Estimate pollutant loads

STEP 3FINALIZE GOALS AND ID SOLUTIONS

–Set goals and management objectives–Develop indicators/targets–Determine load reductions needed–ID critical areas–ID management measures needed

STEP 4DESIGN IMPLEMENTATION PROGRAM

–Develop Implementation schedule–Set Interim milestones–Determine how you will measure success–Develop monitoring component–Develop evaluation process–ID technical and financial assistance needed–Assign responsibility

k

Watershed Planning Steps

STEP 1BUILD PARTNERSHIPS

–ID stakeholders–ID issues of concern–Set preliminary goals–Develop indicators–Conduct outreach

STEP 2CHARACTERIZE WATERSHED

–Gather existing data–Create data inventory–ID data gaps–Collect additional data, if needed–Analyze data–ID causes and sources–Estimate pollutant loads

STEP 3FINALIZE GOALS AND ID SOLUTIONS

–Set goals and management objectives–Develop indicators/targets–Determine load reductions needed–ID critical areas–ID management measures needed

STEP 4DESIGN IMPLEMENTATION PROGRAM

–Develop Implementation schedule–Set Interim milestones–Determine how you will measure success–Develop monitoring component–Develop evaluation process–ID technical and financial assistance needed–Assign responsibility

STEP 5IMPLEMENT WATERSHED PLAN

–Implement management strategies–Conduct monitoring –Conduct outreach activities

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Watershed Planning Steps

STEP 1BUILD PARTNERSHIPS–ID stakeholders–ID issues of concern–Set preliminary goals–Develop indicators–Conduct outreach

STEP 2CHARACTERIZE WATERSHED

–Gather existing data–Create data inventory–ID data gaps–Collect additional data, if needed–Analyze data–ID causes and sources–Estimate pollutant loads

STEP 3FINALIZE GOALS AND ID SOLUTIONS

–Set goals and management objectives–Develop indicators/targets–Determine load reductions needed–ID critical areas–ID management measures needed

STEP 4DESIGN IMPLEMENTATION PROGRAM

–Develop Implementation schedule–Set Interim milestones–Determine how you will measure success–Develop monitoring component–Develop evaluation process–ID technical and financial assistance needed–Assign responsibility

STEP 5IMPLEMENT WATERSHED PLAN

–Implement management strategies–Conduct monitoring –Conduct outreach activities

STEP 6MEASURE PROGRESS AND MAKE ADJUSTMENTS

–Review and evaluate –Share results–Prepare annual plans–Make adjustments

Steps in the Watershed

Planning and Implementati

on Process

EPA’s Nine Elements for Plans

a. Identify causes & sources of pollutionb. Estimate load reductions expected c. Describe mgmt measures & targeted critical areasd. Estimate technical and financial assistance needed e. Develop education component f. Develop schedule g. Describe interim, measurable milestonesh. Identify indicators to measure progressi. Develop a monitoring component

Source: US EPA, 2004 319 Supplemental Guidelines

Incorporation of the nine minimum elements

Contents of the Watershed Plan

• Introduction– Plan area & description, partners, background

• Water quality information & analysis– WQ goals, monitoring/assessment results– Key pollutants / stressors, sources, current loads

• Proposed management measures– Load reductions needed, BMP types proposed– Reductions expected from BMPs, installation sites

• Implementation plan– Public info/education & outreach/involvement plan– BMP/$$/TA support sources, project schedule & costs

• Monitoring and adaptive management approach– Interim measurable milestones, load reduction criteria– Evaluation framework, monitoring plan & partners

Existing loads come from:• Point-source discharges (NPDES

facilities)– Info is available on the discharges (DMRs, etc.)– Some are steady-flow, others are precip-driven

• Nonpoint sources (polluted runoff)– All are (mostly) precip-driven– Calculating the “wash-off, runoff” load is tough– Literature values can be used to estimate– Modeling gets you closer . . . . do you need it?

• Air / atmospheric deposition– Can be significant in some locations

What is a “load?”

• Maybe measured by weight . . . – Kilograms of N per day– Pounds of P per week

• Maybe not . . . – Concentration-based expression of the “load”

(e.g., milligrams per liter)• mg/L x L/day = mg/day [C = m/v]

– # of treatment systems needing inspections, service/pumping, repairs, or replacement

– of miles of streambank needing stabilization or vegetation

– # of AFOs requiring nutrient plans

Combining data sources and modeling watershed “behavior”

Source: STATSGO Database, USDA-

NRCS

NRCS ratings based on soils,

slopes, and groundwater

Many assessment

tools are out there,

e.g., DRASTIC,

MANAGE, & others

Relating endpoints to models

Who will implement the plan?

Structure can vary widely– Public agencies

• Cities, counties• Water or wastewater utility• State agency or river authority• Basin planning teams

– Private entities• Watershed association• Ag producer council

Any well-organized single or multiple entity approach

can coordinate and document the effort

The good, the bad, and the unknown

Watershed assessment and management has the potential to change the way people look at wastewater treatment infrastructure

Rocky Mountain Institute

Cost/Benefit Analysis of Centralized

and Decentralized Wastewater

Options

www.rmi.org

The Good• Onsite & decentralized systems are not a big

problem in most places– Agriculture, “big pipe” treatment system CSOs & SSOs,

construction/development, urban runoff, & etc. are more significant– Notable exceptions exist in some localities, with high public

attention & interest in solutions (e.g., homes around a recreational lake)

• Decentralized wastewater treatment technologies are dependable & performing well, for the most part– Greater acceptance of new technologies in more places

• New focus on perpetual management can address poor public perceptions and improve acceptance– Management is also creating new business opportunities

• Combined sewer overflow and sanitary sewer overflow problems increase interest in decentralized approaches

CSOs locations in the US

CSOs and SSOs

• 850 billion gallons discharged annually from 43,000 combined sewer overflow events

• 9,348 CSO outfalls located in 32 states and DC

• $88 billion needed to address CSOs

• ~50,000 sanitary sewer overflows annually discharge 3-10 billion gallons

• $50.6 billion needed for SSOs

The Bad

• Approvals for new technologies still difficult in some jurisdictions

• Wastewater codes being used as de facto zoning in many locales

• System selection/design driven by site – rather than watershed – considerations

• Integration of wastewater and stormwater planning is moving slowly

• More technical expertise is needed in local regulatory and planning agencies

Folly Beach, SC Survey

The Unknown• How much $$ will be available (or not) for

wastewater treatment infrastructure?• Will public & private entities become more

willing to function as RMEs?• Will system users be willing to pay fees?• Will CSO & SSO enforcement drive more

cities to consider decentralized solutions?• Will planning & zoning ‘grow up’ during this

millennium?• Will ‘decentralized’ or ‘modular’ treatment

approaches gain widespread acceptance?• Are planners and builders making the

connection between low impact development & decentralized wastewater management?

Lot Yield Plan – Used to determine # of lots allowed by zoning, using a conventional subdivision layout

Source: Arendt, Conservation Design for Subdivisions

Source: Arendt, Conservation Design for Subdivisions

Site plan using conservation design principles