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Combined Sewer System Permit and Long TermControl Plan Update

CSS Stakeholder GroupMeeting #1

October 12, 2017

City of Alexandria - Department of Transportationand Environmental Services

Alexandria Renew Enterprises

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PRESENTATION OUTLINE

Purpose and Goals

City – AlexRenew Partnership

Combined Sewer System (CSS)

Overview 2016 Long Term Control Plan Update 2017 State Legislation

Combined Sewer Overflow Strategies

CSS Stakeholder Group Meeting Schedule

Questions and Public Comment

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Purpose and Goals

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Public Participation Goals

Increase stakeholderawareness of the City’s

combined sewersystem and the Long Term

Control Plan Update program.

Develop basicunderstanding of theLong Term ControlPlan Updaterecommendedstrategies.

Awareness,consideration andresponsiveness on theLong Term Control Plan.

Solicit feedback onthe combined sewer

control strategyrecommendations.

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How the Long Term Control PlanUpdate Might Affect the Community

• Improved water quality in Hunting Creek, Oronoco Bay andthe Potomac River

• Potential for ancillary benefits

• Noise, road closures, construction traffic, right-of-wayacquisition, dust, other community impacts

• The Long Term Control Plan projects will be part of the City’sand AlexRenew’s capital improvement budgeting process

• Sewer rate impacts

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Provide recommendations on how a primary strategy canaccomplish the City’s goals and permit requirements whileminimizing impacts to the community

Review and monitor the preparation of the Long Term ControlPlan

Permit and regulatory issues

Engineering and analysis of infrastructure alternatives

Implementation plan schedule and funding strategy

Serve as a central information receiving/dissemination bodyrelated to the Long Term Control Plan

Stakeholder Group Charge(Resolution No. 2781)

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City – AlexRenew Partnership

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History of Working with the City for Clean Water

Overview of AlexRenew

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Major Upgrades to Improve Chesapeake and AddressLocal Water Quality Actions

Overview of AlexRenew

1970s – 1980s$100 Million

1999 – 2006$350 Million

2011 – 2016$160 Million

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AlexRenew Wet Weather Timeline

CLEAN WATERWAYS

1995:Initiated wetweather studies

1999:Wet WeatherFlow ReductionStrategy

2007:Wet WeatherFlow ModelUpdate

2013:Our PermitRequires WetWeatherRemediation

2010:Joint WetWeatherSolutionPresented

1990s:National CSOPolicy and FirstCSS Permit 1999:

ApprovedLong TermControl Plan

2010:HuntingCreekTMDL

2016:Long TermControl PlanUpdate

2017:CSOLegislation

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CSO003

CSO004

CSO 001

CSO 002

Jon

esP

oin

t

Cameron RunHunting Creek

Po

tom

ac

Riv

er

Ho

off

sR

unHooffs Run

JunctionChamber

CommonwealthInterceptor

Potomac YardsTrunk Sewer

PotomacInterceptor

AlexRenew VPDESPermitted Outfall

Holmes RunTrunk Sewer

RelocatedCSO 004

Tu

nn

el

AlexRenew Wet Weather Program

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City’s Combined Sewer System(CSS) Overview

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Separate Sewer System

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Combined Sewer System

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Combined sewercommunities areconcentrated in oldercommunities in the NorthEast and the Great Lakesregions.

Currently, 772 authorizeddischarges from 9,348combined sewer outfalls in32 states and DC

Nearby combined sewercommunities includeWashington, DC,Richmond, and Lynchburg.

Location of Combined SewerSystem (CSS) Communities

Photo/Graphics Source: www.theodorelim.gov

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Combined Sewer System

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Total Area = 540acres (6% of City)

Four permittedoutfalls:

• CSO-001 toOronoco Bay

• CSO-002 toHunting Creek

• CSO-003 toHooffs Run

• CSO-004 toHooffs Run

• Outfalls permittedby the VirginiaDepartment ofEnvironmentalQuality (VDEQ)

Combined SewerService Area

Duke St.CSO-003 & CSO-004

Pendleton St.CSO-001

Royal St.CSO-002

Hunting Creek

Hooffs Run

Poto

mac

Riv

er

Alexandria RenewEnterprises Water Resources

Recovery Facility

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Combined SewerOverflow (CSO)

Locations

Hunting Creek: CSO-002

Hooffs Run:CSO-003 & 004

Oronoco Bay: CSO-001

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City’s CSS Timeline

CLEAN WATERWAYS

1995:Initiated wetweather studies

1999:Wet WeatherFlow ReductionStrategy

2007:Wet WeatherFlow ModelUpdate

2013:Our Permit RequiresWet WeatherRemediation

2010:Joint WetWeatherSolutionPresented

1990s:National CSOPolicy and FirstCSS Permit 1999:

ApprovedLong TermControl Plan

2010:HuntingCreekTMDL

2016:Long TermControl PlanUpdate

2017:CSOLegislation

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Regulatory Paradigm Shift

• City’s existing Long Term Control Plan based on best practices foroperation and maintenance of combined systems.

• Proactive separation as part of Area Reduction Plan.• Monitoring and modeling of combined sewer overflows.

• Must address the Hunting Creek Total Maximum Daily Load.• Must address the 2017 state legislation.

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Clean Water Act goal that all waters of the United States be“fishable” and “swimmable”

State develops impaired waters list and total maximum daily loads

Hunting Creek listed as animpaired water for E. colibacteria

Clean Water Act GoalsTotal Maximum Daily Load (TMDL)

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Sources of Bacteria in HuntingCreek TMDL

Virginia Bacteria Water Quality Criteria 126 E.coli counts per 100mL

Sources of Bacteria: Stormwater Wildlife Pets

Combined Sewer System Sanitary Sewer Overflows AlexRenew Water Resource Recovery

Facility (WRRF) Septic Systems

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Hunting Creek Bacteria TMDL and CSOs:

Total overall bacteria reduction from CSO dischargesof 86%:

99% reduction from Outfalls 003 and 004 (Hooffs Run)

80% reduction from Outfall 002 (Hunting Creek)

Applicable to Outfalls 002, 003, and 004 only

CSS Permit issued in August 2013 requires City toaddress TMDL through an update to its Long TermControl Plan

Hunting Creek BacteriaTotal Maximum Daily Load

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2016 CSS Long Term ControlPlan Update

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OtherPotential

Opportunities

Targeted Sewer SeparationComplementary Strategy

Green InfrastructureComplementary Strategy

Store and TreatPrimary Strategy

2016 Long Term Control PlanUpdate Framework

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Store and treat: build CSO storage and send to thewastewater treatment facility after CSO event for highlevel of treatment Storage tanks (underground)

Deep tunnels

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2016 LTCPU: Store and TreatPrimary Strategy

DC Water: TunnelBoring Machine

Toronto: Keelesdal-Hyde AveUnderground CSO Storage Tank

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10-foot diameter tunnel fromDuke Street to AlexRenewWRRF 1.6 million gallons storage

Less than 4 overflows in a typicalyear

Shafts range in diameter from20-ft to 30-ft

Shafts and tunnel range indepth from 60-ft to 100-ft

Benefits Substantial reduction in CSO

occurrences and volume

Reduces basement backups

Maximizes pollution reduction

2016 LTCPU:CSO-003/004 Project

Dropshaft Existing CSOsExisting CSOs

Alexandria Renew EnterprisesWater Resources Recovery Facility

RelocatedCSO-004

Alexandria NationalCemetery

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2016 LTCPU:CSO-002 Storage Tank Alternatives

CSO-002 Project:• 3 million gallons

of storage• Less than 4

overflows in atypical year

• All tank locationalternativesunderconsideration

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Green Infrastructure

Reduce the amount of stormwater

Provide ancillary environmental andcommunity benefits

City-led and developer-led projects

Targeted Sewer Separation

Condition of redevelopment

Began to implement in early 2000s

Focus in CSO-001 Area(North Old Town Small Area Plan)

2016 LTCPUComplementary Strategies

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2017 State Legislation

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Requires VDEQ by July 1, 2018 to determine what actions bythe City are necessary to bring all combined sewer outfalls intocompliance

Requires initiation of construction activities by July 1, 2023

Requires completion of construction by July 1, 2025

Requires City to submit to VDEQ annual report on progress ofmeeting state legislation

Recent State LegislationSigned into law April 26, 2017

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Significantly accelerates the Long Term Control Plan Updateschedule for outfalls impacted by the Hunting Creek TMDL

Requires CSO-001 project based on EPA CSO PresumptionApproach

Planning Process

Potential to address CSO-001 and 002 together

Additional strategies to be considered working with AlexRenew

Refinement of CSO-003/004 project

Focus will be on meeting mandated schedule

Additional community and stakeholder engagement

Revision to Long Term Control Plan Update

What does this mean for the LTCPU?

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Reevaluate combined sewer strategies

Reengage the community

Revise the Long Term Control Plan Update and send to VDEQby June 1, 2018

Looking Forward

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Combined Sewer OverflowStrategies

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Store and treat: build CSO storage and send to AlexRenew afterCSO event for high level of treatment (basis of 2016 LTCPU)

Underground storage tanks

Deep tunnels

Convey and treat: leverage the current capacity at AlexRenew totreat the flow during a CSO event

Convey additional flows to AlexRenew through deep storage tunnelsand pumping

Allows for smaller sized tunnels

May require building a separate wet weather treatment facility (i.e. UVdisinfection) when flows exceed plant capacity

Combined Sewer Strategies

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Storage and ConveyanceTunnels

DC Water: Tunnel Boring Machine

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Storage Tanks

Toronto: Keelesdal-Hyde AveUnderground CSO Storage Tank

AlexRenew:Nutrient Management Facility Tank

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Ultraviolet Disinfection

AlexRenew:UV Disinfection Facility

AlexRenew:UV Reactor

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CSS StakeholderMeeting Schedule

OCTOBER

2017

NOV/DEC

2017

NOV/DEC

2017

JAN/FEB

2018FEBRUARY

2018

MARCH

2018

Introduction/

Background

Evaluation

Criteria and

Shortlist of

Alternatives

(all four outfalls)

Water Quality

Benefits/

Level of

Control

Preferred

Alternative Implementation Wrap-Up

Discuss the

CSS/WW Plan

history, the 2016

LTCPU

submission, and

the new

legislation.

Introduce the

technologies

under

consideration.

.

Introduce the

shortlist of

alternatives and

discuss the

advantages and

disadvantages.

Review and

discuss the

evaluation criteria

and process

Discuss

benefits and

challenges

of the

alternatives.

Present and

discuss the

preferred

alternative.

Discuss the

potential

impacts to the

community.

Discussion

implementation,

costs, rate

impacts and

schedules.

Wrap and

present draft

plan.

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Questions and PublicComment

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For more information, contact:

William.Skrabak@alexandriava.gov

703.746.4065

Erin.BevisCarver@alexandriava.gov

703.746.4154

www.alexandriava.gov/CleanWaterways

Questions/Suggestions/Comments

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Thank You