Climate Change and Sustainable Water Infrastructure: King County

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Climate Change and Sustainable Water
Infrastructure King County

• David Monthie
• King County DNRP
• January 2008
• 2008 Symposium on Innovating for Sustainable
  Results

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Presentation Objectives

• Adaptation Basics Guidebook, King County Climate
  Plan
• Recent successes in Water Supply, Flood
  Management
• Developing Wastewater Strategy
• Final thoughts and suggestions

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King County looks like this.
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And this.
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And this.
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Some Facts about King County

• 2,134 Square Miles
• 1.8 Million residents (14th largest county in
  U.S.)
• 39 Cities
• Farmland and the Cascade Mountains on the east
  side, Puget Sound and urban coastline on the west
  side
• Three listed fish species under ESA (chinook
  salmon, bull trout, steelhead)
• County govt provides local services and regional
  services include regional transit, sewage
  treatment, solid waste disposal, flood control,
  regional parks, public health

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Major Water Utilities

• Water supplied by three major utilitiesSeattle
  (70), Tacoma, Everettall with surface supply
  sources from Cascades
• Regional wastewater system operated by King
  County 30 local collection systems
• Countywide flood management district operated by
  King County (as of 2007)
• Stormwater utilities operated by local govts,
  incl King County in unincorporated

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Insight from a Notable American Philosopher

• The future ain't what it used to be.
• -- Yogi Berra

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Local Evidence of Climate Change on Water (UW CIG)

• Declining snowpack
• Shifts in timing of runoff
• Declining trend on overall runoff volume

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What We Forecast

• Higher temps by 2100 PNW temp increases more
  than global avg now, up roughly 1.8 degrees F
  every 25 years
• Total precip may go up more rain than snow
  storm intensity likely to increase
• PNW snowpack will decline runoff earlier
• Increased risk of floods and drought
• Rises in sea level levels speculative
• Unclear impacts to groundwater

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King County Actions

• Creation of formal Global Warming Team w/in
  Executives office
• Executive orders lower carbon emissions, greater
  use of advanced technology, new energy policies
  and the increased use of biodiesel
• Comprehensive strategy addressing both mitgation
  and adaptation(2007 Climate Plan)
• Take home leadership at the top makes a big
  difference

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2007 King County Climate Plan

• Includes both Mitigation and Adaptation
• 170 ppacross all sectors of County activities
• Includes goals, activities, milestones, measures
• Includes KC work and collaborations
• Annual report/update

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Climate Change Guidebook

• Preparing for Climate Change A Guidebook for
  Local, Regional and State Governments
• Developed with UW and ICLEI
• Builds on KC experiences

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Climate Change Guidebook--Approach

• ID relevant areas
• Vulnerability Assessment
• Risk Assessment
• Adaptation Strategy
• Implement
• Measure

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Relevant AreasWater (identified in 2007 Climate
Plan)

• Water supplies threats from declining snowpack,
  reduced flows, higher temps, increasing demands
• Flooding threats from higher flows, more intense
  events, aging infrastructure, development
• Wastewater threats from rising sea levels,
  intense storms, existing capacity issues

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Water supplies Vulnerability and Risk Assessment

• Convened regional water planning process in 2005
• Includes major water utilities, local govts,
  enviros, tribes, others
• Work revolving around 7 technical committees by
  substantive topic geographic scope varied
• Climate Change Committee w/UW CIG as tech lead,
  three-county geographic scope

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Climate Change Building Blocks

• Peer-reviewed literature
• What is known and widely accepted about climate
  change

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Downscaled Global Models

• 3 GCMs w/2 GHG scenarios
• Downscaled to apply to King County watersheds
• Meteorology entered into hydro models
• Streamflow forecasts to 2075

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• 2000 2026

2050 2075
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• 2000 2026

2050 2075
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Projected Changes in Spring Flows 2000 to 2075
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Projected Changes in Summer Flows 2000 to 2075
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Projected Changes in Winter Flows 2000 to 2075
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Water Utility Risk Assessment and Adaptation

• Water utilities (Seattle, Tacoma, Everett) used
  streamflow data as input to system models (vs.
  historic meteorology/hydrology)
• Key impacts are changes in timing of flows
• Utility forecasted impacts on firm yield by 2075
  of -3 to -18 annually, possibly more
• Allows for planning mitigation steps already
  being identified by utilities
• Unaddressed issues, e.g.,multiyear drought,
  storms

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Flood and Stormwater Management

• KC has six major rivers, and more than 115 miles
  of riverbank
• Floods are controlled to some extent by an aging
  system of 500 levees/revetments
• FEMA-driven flood plain management is based on
  old maps (remember Yogi!)
• New mapping underway in WAproposed floodplain
  boundaries creating concerns for residents

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Vulnerability and Risk Assessment for Flood and
Stormwater Systems

• Low-lying developed areas could be floodedcould
  include Boeing Renton plant, Southcenter major
  shopping area
• Econ study one event could generate 42 million
  harm
• Physical risk many levees built of soft
  sandsusceptible to repeat events
• Scour in streambeds and stormwater channelsloss
  of functions and habitat, impact on ESA recovery
  plans
• Warming could result in changes to vegetation
  that helps in managing high precipitation events
• Management issues multiple flood districts,
  competing interests with water suppliers

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Adaptation and Planning Response

• New Countywide Flood Hazard Management Plan
• 179 million in projects over 10 yearsincluding
  levee fixes, acquisition of flooding properties,
  expanded Warning Center, restrictions on
  development in floodplains
• Creation of countywide flood control district
  (consolidate existing districts)
• Approval of regional funding source (property
  tax)
• New stormwater manualemphasizes processes to
  mimic natural hydrology
• Active efforts to preserve forest and natural
  lands
• Low impact development emphasis in land use, esp
  critical and vulnerable areasnew Shoreline plan

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King Countys Wastewater Service Area

• 34 Local Agencies
• Two Regional Treatment Plants
• Serves 1.4 million
• Service Area 414 square miles
• Combined 70 square miles
• King County Sewers 335 miles
• Local Agency Separated Sewer 3,300 miles

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Regional Wastewater System Basics

• System designed and constructed based on historic
  data (including rainfall)capacity based on
  historic peak flows (remember Yogi!)
• Effects on planning/operation related to both
  combined and separated sewers
• Location of combined sewer outfalls (CSOs)
  determined by highest observed tides
• II drives capital costs75 peak flows in
  separated system, 90 in combined
• Recl water not built into planninguntil now

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Wastewater System Vulnerability and Risks

• Increased rainfall/intense events raise questions
  of cost to construct capacity, and whether the
  system will be overwhelmed
• New high tides could back up CSOs, cause
  saltwater damage to system
• Major investment decisions 2006 capital budget
  for combined system is 780 million through 2050
  400 million for separated budget is rising
  (adopted 2008 five-year capital budget is 1.938
  billion)

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Risk CSOs Influenced by Tide
Combined Sewer Outfalls (CSOs) Influenced By Tide

• Elevation of CSO Outfalls Determined by Highest
  Observed Tide

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King County 2007 Climate Plan

• WTD Action Items
• To promote regional water supply resilience, by
  maximizing development and use of reclaimed water
  from the wastewater treatment system and explore
  additional reuse approaches and applications
• To support operational resilience of wastewater
  treatment in the most cost effective way possible

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King County 2007 Climate Plan

• To promote regional water resource resilience, by
  maximizing development and use of reclaimed water
  Inventory all non-potable uses in region
• Develop reclaimed water feasibility
  studycompleted December 2007
• Promote industrial and irrigation applications of
  reclaimed water to offset impacts to water supply
  and stream flows
• Work with state, regional, local governments to
  expand use of reclaimed watertask forces

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King County 2007 Climate Plan

• 2. To support operational resilience of
  wastewater treatment facilities
• Collaborate with climate science experts to
  develop reasonable regional assumptions for
  long-range planning purposes
• Develop a reclaimed water comprehensive plan for
  regional production, distribution and application
  to support natural water systems
• Develop strategies to manage wet weather impacts
  of climate change to the sewer system

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Wastewater King County 2007 Climate Plan

• Collaborate with climate science experts to
  develop reasonable regional assumptions for
  long-range planning purposes
• Obtain more detailed local and regional climate
  information upon which to base planning
  assumptions
• Provide consistency between multiple agencies and
  departments
• Further understanding of future impacts and costs
  across agencies and departments

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Wastewater Adaptation Identify Vulnerable
Facilities

• Goal - Identify WTD facilities impacted by storm
  surge/sea level rise (above extreme high water),
  and intense storm/urban flows, and the impact on
  each facility
• GIS based analysis to be completed in 2008
• Identify the impact threshold (consultant)
• Identify the level of impact (consultant)

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Wastewater Adaptation ID Potential Strategies

• Develop response strategies
• Identify adaptive strategies for each facility
  (i.e., berm, armoring, relocation, etc.)
• Identify operational strategies (facility
  specific and system-wide)
• Develop cost estimates and schedules

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Wastewater Develop Adaptation Plan

• Update and integrate capital and asset management
  plans accordingly
• Select strategies
• Revise capital and asset management plans (e.g.,
  capital investment thresholds asset replacement
  schedules)
• Revise operational protocols
• Complete asap2009 (?)

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Wastewater Adaptation Strategy

• Develop a reclaimed water comprehensive plan for
  regional production, distribution and application
  to support natural water systems
• Utilize reclaimed water as a drought-resistant
  source of supply for multiple purposes
• Model integration of wastewater planning and
  water resource planning, in collaboration with
  stakeholders

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Wastewater Adaptation Plan

• Develop strategies to manage wet weather impacts
  of climate change to the sewer system
• Combined Sewer Overflow strategies
• Inflow and Infiltration strategies
• Separated conveyance system strategies
• --Could be similar to strategies for CSOs (e.g.,
  armoring, berms, etc)

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Storm Intensity

• Difficult to predict w/climate models
  area-specific
• Significant issues for urban stormwater
• November 2006 5 precip in 24 hours-gtone death,
  millions in claims in Seattle
• November 2007 4 precip in 24 hours (second
  highest in 50 years)-gtdifferent areas of Seattle
  flooding
• I-5 shutdown 4 days below Olympia

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WTD System Performance and Vulnerability

• System performed well given size of the storm and
  the amount of urban flooding
• Treatment plants ran at or over capacity during
  the entire storm, did not have any major failures
  or damage
• Problems w/pumps handling volume of treated water
• Urban flooding/II overwhelmed some
  facilitiesflows to streams, beaches

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Carkeek CSO Treatment Plant Grit Tank
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Carkeek CSO Treatment Plant Sedimentation Tank
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December 2007 storm Summary

• Plants and whole system ran at or over its
  capacity
• Need to work with local jurisdictions on urban
  flooding impacting our system
• Need to work on infiltration/inflow (I/I)
• Need additional capacity (third treatment
  plantBrightwater)
• Need long-term climate strategy

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Water Resource and Management Challenges

• Evolving science will require dynamic planning
  and decision making
• Investment risks what are appropriate
  thresholds, who bears the risk
• New approaches e.g., decentralization and
  flexibility in order to increase resilience
  integration (reclaimed water as resource)
• Inadequate management structures and
  institutions competing interests (flood
  management vs. water supply), regional approaches
• Costs will likely be high

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Suggestions for national support

• Encourage or require states to incorporate
  climate change into appropriate planning
• Condition financial assistance funding (e.g.,
  SRF) on accounting for climate change in utility
  infrastructure planning
• Provide direct technical assistance or financial
  support (e.g., downscaling)
• Provide a one-stop clearinghouse for all
  categories of climate change information

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More resources

• Climate Change Tech Comm report (UW CIG)
  www.cses.washington.edu/cig/fpt/planning
• KC global warming http//www.metrokc.gov/global
  warming
• KC flood hazard management plan
  http//www.metrokc.gov/wlr/flood/FHMP
• International Council for Local Environmental
  Initiatives (Guidebook) http//www.iclei.org/
  and UW CIG (see above)
• KC regional water planning www.govlink.org/region
  al-water-planning