Combined Sewer System Permit and Long Term Control Plan Update CSS - - PowerPoint PPT Presentation

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Combined Sewer System Permit and Long Term Control Plan Update CSS - - PowerPoint PPT Presentation

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Combined Sewer System Permit and Long Term Control Plan Update CSS Stakeholder Group Meeting #1 October 12, 2017 City of Alexandria - Department of Transportation and Environmental Services Alexandria Renew Enterprises 1 PRESENTATION

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Combined Sewer System Permit and Long Term Control Plan Update CSS Stakeholder Group Meeting #1 October 12, 2017

City of Alexandria - Department of Transportation and 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 stakeholder awareness of the City’s combined sewer system and the Long Term Control Plan Update program. Develop basic understanding of the Long Term Control Plan Update recommended strategies. Awareness, consideration and responsiveness on the Long Term Control Plan. Solicit feedback on the combined sewer control strategy recommendations.

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How the Long Term Control Plan Update Might Affect the Community

  • Improved water quality in Hunting Creek, Oronoco Bay and

the Potomac River

  • Potential for ancillary benefits
  • Noise, road closures, construction traffic, right-of-way

acquisition, dust, other community impacts

  • The Long Term Control Plan projects will be part of the City’s

and AlexRenew’s capital improvement budgeting process

  • Sewer rate impacts
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 Provide recommendations on how a primary strategy can accomplish the City’s goals and permit requirements while minimizing impacts to the community  Review and monitor the preparation of the Long Term Control Plan

 Permit and regulatory issues  Engineering and analysis of infrastructure alternatives  Implementation plan schedule and funding strategy

 Serve as a central information receiving/dissemination body related 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 Address Local 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 wet weather studies 1999: Wet Weather Flow Reduction Strategy 2007: Wet Weather Flow Model Update 2013: Our Permit Requires Wet Weather Remediation 2010: Joint Wet Weather Solution Presented 1990s: National CSO Policy and First CSS Permit 1999: Approved Long Term Control Plan 2010: Hunting Creek TMDL 2016: Long Term Control Plan Update 2017: CSO Legislation

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CSO 003 CSO 004 CSO 001 CSO 002

Jones Point

Cameron Run Hunting Creek Potomac River

Hooffs Run

Hooffs Run Junction Chamber Commonwealth Interceptor Potomac Yards Trunk Sewer Potomac Interceptor AlexRenew VPDES Permitted Outfall Holmes Run Trunk Sewer Relocated CSO 004 Tunnel

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 sewer communities are concentrated in older communities in the North East and the Great Lakes regions.  Currently, 772 authorized discharges from 9,348 combined sewer outfalls in 32 states and DC  Nearby combined sewer communities include Washington, DC, Richmond, and Lynchburg.

Location of Combined Sewer System (CSS) Communities

Photo/Graphics Source: www.theodorelim.gov

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Combined Sewer System

16 Total Area = 540 acres (6% of City) Four permitted

  • utfalls:
  • CSO-001 to

Oronoco Bay

  • CSO-002 to

Hunting Creek

  • CSO-003 to

Hooffs Run

  • CSO-004 to

Hooffs Run

  • Outfalls permitted

by the Virginia Department of Environmental Quality (VDEQ)

Combined Sewer Service Area

Duke St. CSO-003 & CSO-004 Pendleton St. CSO-001 Royal St. CSO-002 Hunting Creek Hooffs Run

Potomac River

Alexandria Renew Enterprises Water Resources Recovery Facility

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Combined Sewer Overflow (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 wet weather studies 1999: Wet Weather Flow Reduction Strategy 2007: Wet Weather Flow Model Update 2013: Our Permit Requires Wet Weather Remediation 2010: Joint Wet Weather Solution Presented 1990s: National CSO Policy and First CSS Permit 1999: Approved Long Term Control Plan 2010: Hunting Creek TMDL 2016: Long Term Control Plan Update 2017: CSO Legislation

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Regulatory Paradigm Shift

  • City’s existing Long Term Control Plan based on best practices for
  • peration 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 an impaired water for E. coli bacteria

Clean Water Act Goals Total Maximum Daily Load (TMDL)

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Sources of Bacteria in Hunting Creek 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 discharges

  • f 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 to address TMDL through an update to its Long Term Control Plan

Hunting Creek Bacteria Total Maximum Daily Load

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2016 CSS Long Term Control Plan Update

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Other Potential Opportunities

Targeted Sewer Separation

Complementary Strategy

Green Infrastructure

Complementary Strategy

Store and Treat

Primary Strategy

2016 Long Term Control Plan Update Framework

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 Store and treat: build CSO storage and send to the wastewater treatment facility after CSO event for high level of treatment

 Storage tanks (underground)  Deep tunnels

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2016 LTCPU: Store and Treat

Primary Strategy

DC Water: Tunnel Boring Machine Toronto: Keelesdal-Hyde Ave Underground CSO Storage Tank

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 10-foot diameter tunnel from Duke Street to AlexRenew WRRF

  • 1.6 million gallons storage
  • Less than 4 overflows in a typical

year

 Shafts range in diameter from 20-ft to 30-ft  Shafts and tunnel range in depth from 60-ft to 100-ft  Benefits

  • Substantial reduction in CSO
  • ccurrences and volume
  • Reduces basement backups
  • Maximizes pollution reduction

2016 LTCPU: CSO-003/004 Project

Dropshaft Existing CSOs Existing CSOs

Alexandria Renew Enterprises Water Resources Recovery Facility

Relocated CSO-004

Alexandria National Cemetery

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2016 LTCPU: CSO-002 Storage Tank Alternatives

CSO-002 Project:

  • 3 million gallons
  • f storage
  • Less than 4
  • verflows in a

typical year

  • All tank location

alternatives under consideration

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 Green Infrastructure  Reduce the amount of stormwater  Provide ancillary environmental and community 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 LTCPU

Complementary Strategies

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2017 State Legislation

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 Requires VDEQ by July 1, 2018 to determine what actions by the City are necessary to bring all combined sewer outfalls into compliance  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 of meeting state legislation

Recent State Legislation

Signed into law April 26, 2017

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 Significantly accelerates the Long Term Control Plan Update schedule for outfalls impacted by the Hunting Creek TMDL  Requires CSO-001 project based on EPA CSO Presumption Approach  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 VDEQ by June 1, 2018

Looking Forward

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Combined Sewer Overflow Strategies

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

 Underground storage tanks  Deep tunnels

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

 Convey additional flows to AlexRenew through deep storage tunnels and pumping  Allows for smaller sized tunnels  May require building a separate wet weather treatment facility (i.e. UV disinfection) when flows exceed plant capacity

Combined Sewer Strategies

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Storage and Conveyance Tunnels

DC Water: Tunnel Boring Machine

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Storage Tanks

Toronto: Keelesdal-Hyde Ave Underground 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 Stakeholder Meeting Schedule

OCTOBER 2017 NOV/DEC 2017 NOV/DEC 2017 JAN/FEB 2018 FEBRUARY 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

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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 Public Comment

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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