Brightwater Project, Membrane Bioreactor (MBR), King County, WA, USA
Key Data:
Plant type
Municipal WWTP
Capacity
Initial capacity (2010)
136,000m³/d (average), 495,000m³/d (peak flow)
Capacity by 2040
205,000m³/d (average), 645,000m³/d (peak flow)
Secondary treatment type
Membrane bioreactor
Effluent BOD
<5mg/L
Effluent TSS
<2mg/L
Effluent NH3-N
<1mg/L
Effluent TN
<5mg/L
Effluent TP
<0.1mg/L
Effluent turbidity
<0.5 NTU
Effluent faecal coliform
<10 CFU/100mL
Effluent SDI
<2
Effluent mixed liquor solids concentration
8,000mg/L to 10,000mg/L
Product
Class A reclaimed water
Total site area
114 acres
Treatment and support facilities footprint
43 acres
Membrane bioreactor costs
$30m
Odour control costs
$50m
Mitigation costs
$88m
Construction costs
$280m
Project Timeline:
Regional Wastewater Services Plan approved
November 1999
Identification and evaluation of sites, marine outfall zones and construction methods
2000–2001
Siting process Phase II began
June 2001
Environmental review systems identified
December 2001
Pipeline corridors evaluation
Spring 2002
Environmental review process begins
May 2002
Public meetings
June 2002
Draft EIS issued
November 2002
Public consultation on EIS
December 2002
Final EIS issued
November 2003
Site and system selected
December 2003
Supplemental EIS issued
July 2005
Site selection formally reaffirmed
July 2005
Demolition and clearing work began
November 2005
Subcontractor bidding and selection
Early 2006
Construction began on the north mitigation area of the treatment plant site; preparation work began on the rest of the site; work began on the Bothell and Kenmore tunnels
2006
Site excavation begins; work begins on the Point Wells and Ballinger Way tunnels; treatment plant construction begins
2007
Main pipe installation / construct site portal; marine outfall construction begins, construction of the Bothell influent pumping station begins
2008
Building work completed; M&E installation; conveyance tunnel construction completed
2009
Testing, site restoration and start up
2010/11
Key Players:
Client
King County Wastewater Treatment Division
General contractor / construction manager
Hoffman Construction
Membrane systems
Zenon
