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					  Presentation on Wastewater
            Systems


November 30, 2007
 ENVH 440/545- Group I
     Maricris Eleno
     Erica D. Finsness
     Dana Devin-Clarke
     Sarah Bruce
     Edwin T. Long
               Introduction
• What is LOTT Alliance & why it is unique
• Components of LOTT Alliance
  – Martin Way Reclaimed Water Plant
  – Hawks’ Prairie Ponds
  – Budd Inlet
  – Future Projects
• Conclusion
                        LOTT
  A partnership for wastewater management between:
                        • Lacey
                       • Olympia
                      • Tumwater
                   • Thurston County

Came about in the second half of the twentieth century
Noteworthy because it significantly shifted the
  wastewater treatment paradigm in the Pacific
  Northwest
              Paradigm Shift
• FROM predominantly marine discharge
• TO substantial water recycling

(Note: water recycling is well-established in
  more arid regions, but is a new idea in the
  Pacific Northwest)
          Motivation for the shift
                 Inflow and Infiltration Study
• Conducted 1992-1994
• Found that the LOTT treatment plant could reach capacity in
  wet weather as early as 2001

                  Long range planning process
• Conducted 1995-1999
• Result = Wastewater Resource Management Plan
• First upgrade under the Plan occurred in 2004
Martin Way Reclaimed Water Plant
• First of three satellite reclaimed water plants
• 2-MGD (expandable to 5-MGD)
• Generates reclaimed water meeting Class A
  reclaimed water standards
• Discharged into Hawks Prairie Ponds/Recharge
  Basins
                       MBR Process
• Membrane bioreactors (MBR) provide tertiary treatment
• Aeration tank  Membrane tank
   – Low Vacuums inside of hollow fibers
   – Mixed liquor and air pumped into membrane module
• Benefits
   –   Long sludge retention
   –   Increased MLSS
   –   Reduced biosolids production
   –   Eliminates sludge setteability issues
              Hawks Prairie Ponds/
                Recharge Basins
Class A Reclaimed Water
   – from the Martin Way Reclaimed Water Plant
   – travels 3 miles through a 14-inch purple pipeline to the
     Hawks Prairie Ponds/Recharge Basins site
   – Some water will ultimately be drawn-off along the way
      • for irrigation or other beneficial uses.
• Hawks Prairie Ponds/Recharge Basins site
   – 41 acre
   – reclaimed water circulates through five constructed
     wetland ponds
   – containing about 225,000 wetland plants.
            Purposes of Ponds
• Receiving / Discharging the Class A Reclaimed
  Water
• Public visibility and education
  – public education, recognition, and acceptance of
    reclaimed water
• A community benefit
  – park-like setting, walking trails and benches
  – visitors can view and enjoy a wide variety of
    animals, birds, and aquatic life.
                 Recharge Basins
• Reclaimed water not drawn from the ponds for
  irrigation or other uses will flow to the rectangular
  groundwater Recharge Basins
• Eight on-site recharge cells
   – one acre each
   – allow some cells to be rested and rehabilitated while
     others are in operation
   – no more than four cells are in use at any time
• From there, the water infiltrates through the soils to
  a shallow underground aquifer.
          Recharge basins cont.
• Ponds and basin site will infiltrate water downward
  through the unsaturated zone to the shallow aquifer
  approximately 90-feet below the surface
• Water will then move laterally away from the basins
• Groundwater mounding is expected to occur
• Height of groundwater mounding may be of concern
  because of the potential impacts to the infiltration
  capacity of the basins and the potential problems a
  high water table might create in the surrounding
  area.
Budd Inlet Treatment Plant
    Purpose of Reclaiming the water:
    1) Reduce discharge to Budd Inlet
    2) Make reclaimed water available for use in
       downtown Olympia
    3) Promote public education and public
       acceptance of water reuse


    • Treats 10 – 12 million gallons per
    day

    • Initially 1.5 mgd of will receive
    additional treatment to achieve Class
    A standards
Budd Inlet Treatment Flow Scheme
             Reclaimed Water Usage
• Irrigation of: State’s Heritage Park, Marathon Park, and eventually the
  State Capitol Campus

• Commercial/Industrial use: Port of Olympia equipment and boat
  washdown, dust suppression, and a constructed pond

• Internal Plant use: irrigation, flushing toilets, pump seals and cleaning of
  pump housing
               Future Projects
• Improved capacity including opening up bottlenecks,
  purchasing land and developing additional treatment
  capacity
• Repair and improvement projects that include
  scrubber improvements, digester sludge
  improvements, thickening equipment replacement
  etc.
• Community outreach projects including wetland
  accessibility, educational kiosks and an
  administrative learning facility
             Future Projects
• LEED Co-generation/Reverse Osmosis – a
  project with PSE (Puget Sound Energy) that
  will make use of the digester gas for
  generating heat and electricity, and includes
  evaluating the effective use of a reverse
  osmosis unit
• Habitat improvement in conjunction with the
  Squaxin Island Tribe
                Conclusion
• Unique management techniques
• Effectively manages available resources while
  planning for strategic growth
• Steady, growth strategy looking at ‘triple
  bottom line’
• Could they be doing more to implement more
  environmentally conservative practices?

				
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