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provide the region with the best best the with region the provide biosolids, reclaiming water, recovering energy, energy, recovering water, reclaiming biosolids,
Alternative formats available formats Alternative
operate effectively. Our goal is to to is goal Our effectively. operate wastewater and stormwater, producing producing stormwater, and wastewater
that supply it with wastewater wastewater with it supply that
Plant workers operate facilities for treating treating for facilities operate workers Plant
www.kingcounty.gov/wtd
and the pipelines and pump stations stations pump and pipelines the and to Puget Sound and Seattle’s Discovery Park. Park. Discovery Seattle’s and Sound Puget to
site Web our see or 68286, ext.
staff — ensure the West Point plant plant Point West the ensure — staff north of downtown Seattle on 32 acres next next acres 32 on Seattle downtown of north
206-296-8286 or 1-800-325-6165, 1-800-325-6165, or 206-296-8286
control personnel and administrative administrative and personnel control West Point Treatment Plant Treatment Point West is four miles miles four is The
please call please information further
maintenance employees, process process employees, maintenance
Treatment Plant Tours Plant Treatment or or For PIERCE COUNTY PIERCE
— operators, lab technicians, technicians, lab operators, —
4 Miles 4 2 0
Tacoma KING COUNTY KING
days a week. Trained professionals professionals Trained week. a days
Auburn
Seattle, WA 98199 206-263-3800 98199 WA Seattle,
Way system runs 24 hours a day, seven seven day, a hours 24 runs system
Investment
1400 West Utah Street Utah West 1400 Federal
employees, the West Point treatment treatment Point West the employees, A Sound Sound A
West Point Treatment Plant Treatment Point West
Water – – Water Thanks to about 150 dedicated dedicated 150 about to Thanks
Contact Us: Contact
Clean
THE PEOPLE OF WEST POINT — ‘24/7’ — POINT WEST OF PEOPLE THE Plant
Kent Treatment good neighbor. good
South
Island
a is Point West sure make to work we County, and some areas east of Lake Washington. Lake of east areas some and County,
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Water reclamation, community improvement improvement community reclamation, Water offices, schools, agencies, businesses and industries industries and businesses agencies, schools, offices,
Renton
Plant
We also created a publicly accessible wetland. wetland. accessible publicly a created also We
treats wastewater and stormwater from homes, homes, from stormwater and wastewater treats
Treatment
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Vashon Island Vashon
surrounding community and Discovery Park. Park. Discovery and community surrounding covers 420 square miles. West Point cost-effectively cost-effectively Point West miles. square 420 covers N O I T C E S T S A E N O I T C E S T S A E
to minimize the impact of the plant on the the on plant the of impact the minimize to
million people and and people million 1.4 than Issaquah
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West Point West
Shoreline
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Woodinville KING COUNTY KING
reclaiming wastewater and and wastewater reclaiming
TREATMENT TREATMENT
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SNOHOMISH COUNTY SNOHOMISH Bothell region and the health health the and region
transporting, treating and and treating transporting, Terrace
Mountlake
the of resources
and the environment by by environment the and WEST POINT POINT WEST Edmonds
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Wastewater Treatment Treatment Wastewater N
NEIGHBOR
SERVICE AREA MAP AREA SERVICE
people of King County’s County’s King of people
For more than 40 years, the the years, 40 than more For A GOOD GOOD A
WEST POINT 100 YEARS AGO… MANAGING COMBINED SEWER SYSTEMS King County provides real time notification of CSO CONTROLLING WASTES AT THE discharges at http://www.kingcounty.gov/wtd. In 1911, the City of Seattle built what is called the Fort A combined system is one in which stormwater and SOURCE West Point continues to develop ways to improve Lawton Tunnel to discharge untreated wastewater from sewage are conveyed in the same pipeline to the treatment Responsibilities of the operations and meet or exceed regulatory standards for the city into Puget Sound at West Point. This wastewater plant. The West Point service area is largely a combined Wastewater Treatment effluent quality. included sewage from homes and businesses, stormwater system. As a result, West Point treats a lot of stormwater Division begin even from city streets, and litter and horse manure that washed that would otherwise flow untreated into Puget Sound. before wastewater into the pipes. Increased population and public concerns During heavy rains, the volume of REGULATION AND PERMITTING enters pipes and about water pollution resulted in the creation of a regional treatment plants. flows to West Point can exceed the Like most other treatment plants throughout the United wastewater treatment system. King Couny regulates capacity of the conveyance system. States, West Point discharges treated wastewater every business and industry Under these conditions, excessive day into a local water body, Puget Sound. The 1972 federal to monitor and restrict combined flows may be released Clean Water Act regulates “point” discharges of pollutants. HISTORY through permitted outfalls to protect the type and amount King County voters created Voters decided to public and private property and the A National Pollution Discharge Elimination System of waste that enters the Municipality of merge Metro with WARNING county’s facilities. These events are Permit (available on our Web site) sets effluent the system. We also Metropolitan Seattle King County, and Possible Sewage Overflows During and Following Heavy Rain called combined sewer overflows, or standards and specifications for monitoring, work with the public (Metro) to provide King County Questions? Call: 206-205-1151 wastewater treatment and assumed Regarding CSO # 21 CSOs. King County provides public treating and discharging treated wastewater to provide information through the West Point outfall in Puget Sound. about safe practices and clean the waters of Lake responsibility for notification when CSOs occur. Students touring the treatment plant Washington and Elliott Bay. West Point. alternatives. Preventing King County’s CSO Control Program reports CSO events West Point has consistently been recognized by the learn about wastewater treatment and contaminants from 1958 1966 1991 1993 1996 and develops plans and priorities to reduce the number of National Association of Clean Water Agencies for what they can do to keep harmful entering the sewer CSO events in the county’s system. CSO events have been excellence in wastewater treatment for our continued substances out of the waste stream. Construction Metro began Upgrade to system is the easiest reduced significantly by control strategies including on-site compliance with the NPDES permit. of the West an expansion secondary and least expensive way to protect people and primary treatment and storage facilities that retain flows Point primary of West Point treatment was the environment. Extensive information is available treatment to provide completed. until storms have passed. King County continues to work on our Web site or by calling our division. plant was secondary with state agencies to minimize the number of untreated completed. treatment. discharges each year. DON’T FLUSH TROUBLE! Put used cleaning wipes, cloths and RESOURCES FRO pads in the trash, NOT the toilet! TING M WAS EA TEWA The label might say “flushable”, CR TE Composted biosolids make a but disposable wipes are clogging West Point Treatment R wonderful soil amendment our sewer lines and damaging Plant’s wastewater treatment facilities for gardens and commercial pumps and other equipment. produce many valuable resources that can be ENERGY RECOVERY landscapes. used within the plant and throughout the region. Digester gas is a byproduct Not only are these problems of the biosolids digestion process. It expensive to fix, they can also cause WATER REUSE AND RECLAIMED WATER is a gas composed of methane and carbon BIOSOLIDS Biosolids are the nutrient-rich organic raw sewage overflows into homes, Wastewater treated to secondary standards is dioxide produced by active anaerobic product of treating wastewater. Biosolids provide businesses and local waterways. reused on-site for cleaning and as a water source for bacteria. West Point uses digester gas to power its organic matter that improves soil properties and So, think trash, not toilets! the treatment process. Some of the treated water raw sewage pump engines which require lots of power. enhances plant growth. undergoes further treatment for use where potable In addition, the heat generated from the engines is Some of West Point Treatment Plant’s biosolids are sold
water would otherwise be required saving hundreds of recovered to heat the plant. Digester gas is also used to as a soil amendment for agriculture in Eastern Washington. Department of Natural Resources and Parks thousands of dollars in city water. fire boilers which supply most of the plant’s heat needs. The rest is composted for use in landscaping and gardening. Wastewater Treatment Division www.kingcounty.gov/wtd 206-684-1280
0903westpointBRO.indd
www.kingcounty.gov/wtd www.kingcounty.gov/wtd
l t a h e
h
a
n
c i
Wastewater Treatment Division Treatment Wastewater d l
206-263-6028 or 1-800-325-6165, ext. 36028 ext. 1-800-325-6165, or 206-263-6028
b
t
h u
Natural Resources and Parks and Resources Natural
e p
Seattle, WA 98104-3855 WA Seattle,
t
e
Department of Department
c
n
e
01 S. Jackson Street, Suite 500 Suite Street, Jackson S. 01 2
v
i
r r
d
o
o o h p Wastewater Treatment Division Treatment Wastewater
n
r
and effectively as possible. possible. as effectively and m
o . e t
o n b t
h
g i Department of Natural Resources and Parks and Resources Natural of Department
e
n
operating as efficiently efficiently as operating
r
u
o
K
y
i
n
n
service available while while available service
i g
C g
o n
i u
k n r t o y , w
206-684-1280 or TTY Relay: 711 Relay: TTY or 206-684-1280
wastewater treatment treatment wastewater and testing new treatment technologies. treatment new testing and
provide the region with the best best the with region the provide biosolids, reclaiming water, recovering energy, energy, recovering water, reclaiming biosolids,
Alternative formats available formats Alternative
operate effectively. Our goal is to to is goal Our effectively. operate wastewater and stormwater, producing producing stormwater, and wastewater
that supply it with wastewater wastewater with it supply that
Plant workers operate facilities for treating treating for facilities operate workers Plant
www.kingcounty.gov/wtd
and the pipelines and pump stations stations pump and pipelines the and to Puget Sound and Seattle’s Discovery Park. Park. Discovery Seattle’s and Sound Puget to
site Web our see or 68286, ext.
staff — ensure the West Point plant plant Point West the ensure — staff north of downtown Seattle on 32 acres next next acres 32 on Seattle downtown of north
1-800-325-6165, or 206-296-8286
control personnel and administrative administrative and personnel control West Point Treatment Plant Treatment Point West is four miles miles four is The
please call please information further
maintenance employees, process process employees, maintenance
Treatment Plant Tours Plant Treatment or or For PIERCE COUNTY PIERCE
— operators, lab technicians, technicians, lab operators, —
4 Miles 4 2 0
Tacoma KING COUNTY KING
days a week. Trained professionals professionals Trained week. a days
Auburn
Seattle, WA 98199 206-263-3800 98199 WA Seattle,
Way system runs 24 hours a day, seven seven day, a hours 24 runs system
Investment
1400 West Utah Street Utah West 1400 Federal
employees, the West Point treatment treatment Point West the employees, A Sound Sound A
West Point Treatment Plant Treatment Point West
Water – – Water Thanks to about 150 dedicated dedicated 150 about to Thanks
Contact Us: Contact
Clean
THE PEOPLE OF WEST POINT — ‘24/7’ — POINT WEST OF PEOPLE THE Plant
Kent Treatment good neighbor. good
South
Island
a is Point West sure make to work we County, and some areas east of Lake Washington. Lake of east areas some and County,
Vashon
and active public involvement are other ways ways other are involvement public active and in Seattle, north King County, south Snohomish Snohomish south County, King north Seattle, in
Water reclamation, community improvement improvement community reclamation, Water offices, schools, agencies, businesses and industries industries and businesses agencies, schools, offices,
Renton
Plant
We also created a publicly accessible wetland. wetland. accessible publicly a created also We
treats wastewater and stormwater from homes, homes, from stormwater and wastewater treats
Treatment
A E R A E C I V R E S
A E R A E C I V R E S
Vashon Island Vashon
surrounding community and Discovery Park. Park. Discovery and community surrounding covers 420 square miles. West Point cost-effectively cost-effectively Point West miles. square 420 covers N O I T C E S T S A E N O I T C E S T S A E
to minimize the impact of the plant on the the on plant the of impact the minimize to
million people and and people million 1.4 than Issaquah
and swimmable today swimmable and
d n u o S to odor and noise control and native landscaping landscaping native and control noise and odor to sewer rates and serves more more serves and rates sewer
Seattle
t e g u P
L fishable — Washington Lake
a
At West Point, we have devoted extensive effort effort extensive devoted have we Point, West At k monthly by funded is that
Sammamish e
S
a
A E R A E C I V R E S m
A E R A E C I V R E S
m L system treatment wastewater
a a
m N O I T C E S T S E W
k N O I T C E S T S E W
neighbors and our employees. employees. our and neighbors
Bellevue e
i s
Plant h W regional the of part is
a Environment the and
s facility wastewater environment, natural
h
West Point Treatment Treatment Point West The The i
n
Plant
g
Redmond
t
the affecting projects all of impacts Treatment o
n Health Public Protecting
Carnation Seattle
ensure safety and minimize minimize and safety ensure
protect regional water quality. water regional protect
Plant
generations. We work to to work We generations.
A E R A E C I V R E S A E R A E C I V R E S continually to improve and and improve to continually
PLANT
Treatment
customers and future future and customers A R E WAT T H G I R B A R E WAT T H G I R B
its byproducts. We work work We byproducts. its
West Point West
Shoreline
our of well-being and
Woodinville KING COUNTY KING
reclaiming wastewater and and wastewater reclaiming
TREATMENT TREATMENT
Lake Washington — the ’50s the — Washington Lake
SNOHOMISH COUNTY SNOHOMISH Bothell region and the health health the and region
transporting, treating and and treating transporting, Terrace
Mountlake
the of resources
and the environment by by environment the and WEST POINT POINT WEST Edmonds
protecting the water water the protecting (On-line 2011) (On-line
to protecting public health health public protecting to
Plant
committed to to committed
Division have been committed committed been have Division Treatment
King County is is County King Brightwater
Wastewater Treatment Treatment Wastewater N
NEIGHBOR
SERVICE AREA MAP AREA SERVICE
people of King County’s County’s King of people
For more than 40 years, the the years, 40 than more For A GOOD GOOD A
WEST POINT 100 YEARS AGO… MANAGING COMBINED SEWER SYSTEMS King County provides real time notification of CSO CONTROLLING WASTES AT THE discharges at http://www.kingcounty.gov/wtd. In 1911, the City of Seattle built what is called the Fort A combined system is one in which stormwater and SOURCE West Point continues to develop ways to improve Lawton Tunnel to discharge untreated wastewater from sewage are conveyed in the same pipeline to the treatment Responsibilities of the operations and meet or exceed regulatory standards for the city into Puget Sound at West Point. This wastewater plant. The West Point service area is largely a combined Wastewater Treatment effluent quality. included sewage from homes and businesses, stormwater system. As a result, West Point treats a lot of stormwater Division begin even from city streets, and litter and horse manure that washed that would otherwise flow untreated into Puget Sound. before wastewater into the pipes. Increased population and public concerns During heavy rains, the volume of REGULATION AND PERMITTING enters pipes and about water pollution resulted in the creation of a regional treatment plants. flows to West Point can exceed the Like most other treatment plants throughout the United wastewater treatment system. King Couny regulates capacity of the conveyance system. States, West Point discharges treated wastewater every business and industry Under these conditions, excessive day into a local water body, Puget Sound. The 1972 federal to monitor and restrict combined flows may be released Clean Water Act regulates “point” discharges of pollutants. HISTORY through permitted outfalls to protect the type and amount King County voters created Voters decided to public and private property and the A National Pollution Discharge Elimination System of waste that enters the Municipality of merge Metro with WARNING county’s facilities. These events are Permit (available on our Web site) sets effluent the system. We also Metropolitan Seattle King County, and Possible Sewage Overflows During and Following Heavy Rain called combined sewer overflows, or standards and specifications for monitoring, work with the public (Metro) to provide King County Questions? Call: 206-205-1151 wastewater treatment and assumed Regarding CSO # 21 CSOs. King County provides public treating and discharging treated wastewater to provide information through the West Point outfall in Puget Sound. about safe practices and clean the waters of Lake responsibility for notification when CSOs occur. Students touring the treatment plant Washington and Elliott Bay. West Point. alternatives. Preventing King County’s CSO Control Program reports CSO events West Point has consistently been recognized by the learn about wastewater treatment and contaminants from 1958 1966 1991 1993 1996 and develops plans and priorities to reduce the number of National Association of Clean Water Agencies for what they can do to keep harmful entering the sewer CSO events in the county’s system. CSO events have been excellence in wastewater treatment for our continued substances out of the waste stream. Construction Metro began Upgrade to system is the easiest reduced significantly by control strategies including on-site compliance with the NPDES permit. of the West an expansion secondary and least expensive way to protect people and primary treatment and storage facilities that retain flows Point primary of West Point treatment was the environment. Extensive information is available treatment to provide completed. until storms have passed. King County continues to work on our Web site or by calling our division. plant was secondary with state agencies to minimize the number of untreated completed. treatment. discharges each year. DON’T FLUSH TROUBLE! Put used cleaning wipes, cloths and RESOURCES FRO pads in the trash, NOT the toilet! TING M WAS EA TEWA The label might say “flushable”, CR TE Composted biosolids make a but disposable wipes are clogging West Point Treatment R wonderful soil amendment our sewer lines and damaging Plant’s wastewater treatment facilities for gardens and commercial pumps and other equipment. produce many valuable resources that can be ENERGY RECOVERY landscapes. used within the plant and throughout the region. Digester gas is a byproduct Not only are these problems of the biosolids digestion process. It expensive to fix, they can also cause WATER REUSE AND RECLAIMED WATER is a gas composed of methane and carbon BIOSOLIDS Biosolids are the nutrient-rich organic raw sewage overflows into homes, Wastewater treated to secondary standards is dioxide produced by active anaerobic product of treating wastewater. Biosolids provide businesses and local waterways. reused on-site for cleaning and as a water source for bacteria. West Point uses digester gas to power its organic matter that improves soil properties and So, think trash, not toilets! the treatment process. Some of the treated water raw sewage pump engines which require lots of power. enhances plant growth. undergoes further treatment for use where potable In addition, the heat generated from the engines is Some of West Point Treatment Plant’s biosolids are sold
water would otherwise be required saving hundreds of recovered to heat the plant. Digester gas is also used to as a soil amendment for agriculture in Eastern Washington. Department of Natural Resources and Parks thousands of dollars in city water. fire boilers which supply most of the plant’s heat needs. The rest is composted for use in landscaping and gardening. Wastewater Treatment Division www.kingcounty.gov/wtd 206-684-1280 WASTEWATER TREATMENT PROCESS How is wastewater treated at King County’s West Point Treatment Plant? HAT’S COMI W NG IN Stormwater Inflow, T Groundwater Infiltration O and Street Runoff Commercial Typical Flows by Source T Residential H Industrial During the Winter Months E
Processes P
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Inflow & Residential N 29% T
53% Groundwater ? Infiltration 17% Commercial LOCAL SEWER DISTRICTS LOCAL SEWER DISTRICTS 1% Industrial
Influent Processes KING COUNTY SEWER SYSTEM
Regulator Stations
Pump Stations Combined Sewer Overflow (CSO) during heavy Bar rains PRELIMINARY PROCESSES WITHIN Screens TREATMENT Ri WEST POINT TREATMENT PLANT ver La , ke o r S ou ODOR CONTROL – ‘the Sniff Test’ nd In order to minimize odors, we cover or PRIMARY SECONDARY contain the potentially smelly processes Influent TREATMENT and collect the air for treatment. Pumps TREATMENT
Grit Sedimentation Clarifier Removal Aeration PRELIMINARY TREATMENT Tanks Tanks Tanks ‘Taking out the trash’ Flow Primary Sludge Primary Intermediate • Bar screens remove large debris like Diversion Pumps Structure rags, paper, and leaves from wastewater To Return Activated Sludge Chlorination (influent) as it enters West Point. Landfill Waste Activated Sludge DISINFECTION • After screening, wastewater is pumped into aerated grit chambers Contact Tank that remove sand and gravel. SOLIDS Blend HANDLING Tank • The trash and grit collected during this process are trucked to a landfill. WEST POINT TREATMENT PLANT FACTS Reclaimed PRIMARY TREATMENT a physical Gravity Belt Water Thickeners Design average wet weather flow: process ‘Scum floats; sludge settles’ Advanced • Wastewater settles in long tanks called primary Energy 133 million gallons per day Treatment sedimentation tanks. Heavy organic material sinks Recovery Design peak secondary capacity: Dechlorination to the bottom (as sludge), and light material (fats, Heat, 98º Digester 300 million gallons per day oils and greases) floats to the top (as scum). Powers Internal plant Pump Engines Digester Gas Tanks Design maximum capacity: reuse; other • Skimmers remove scum from the surface 440 million gallons per day during nondrinking uses Effluent of the water and conveyor belts remove peak storms Pumps sludge from the tank bottom. Both are then Outfall pipe: 3,600 feet long, sent onto the solids handling process. Centrifuges 240 feet deep, 600-foot diffuser Outfall Pipe • The treated water, now called primary effluent, Reclaimed water produced: flows to the secondary treatment process. Biosolids Recycling Soil Improvement/ up to 220 million gallons per year Primary treatment removes approximately Landscaping/ Land Reclamation 60 percent of the organic solids. Gardening Biosolids produced: about 50,000 wet tons per year • West Point’s primary treatment system is Puget Sound designed to handle a peak combined flow Digester gas generated: of 440 million gallons a day (mgd). 550 million cubic feet per year 3,600 ft. long 600 ft. Diffuser Effluent Forestry Agriculture SECONDARY TREATMENT a biological process ‘Friendly bugs eating contaminants’ • Primary effluent is pumped to aeration tanks where oxygen is added to encourage growth of useful bacteria naturally present in the wastewater. DISINFECTION ‘Zapping pathogens’ SOLIDS HANDLING • The digested solids are then pumped from • Bacteria eat suspended and dissolved organic • Secondary effluent is chlorinated, destroying most Creating biosolids and energy, ‘Blend, thicken, digesters to equipment that uses centrifuges material in the water. In the process, they produce remaining pathogens, or disease-causing bacteria. digest, dewater’ to remove excess water from the solids. more bacteria. • To protect the receiving water environment, the • Organic solids — primary and secondary scum and • The resulting dewatered solid material is nutrient- • The wastewater then goes to secondary clarifiers, final effluent is dechlorinated before it is released sludge from the sedimentation and clarifier tanks — rich biosolids, safe for use as a soil amendment. large round sedimentation tanks where bacteria are blended and thickened in a gravity-belt thickening through an outfall pipe and diffuser into Puget Sound. • West Point Treatment Plant has been nationally settle to the bottom of the tank as secondary sludge. process. The solids are then pumped to digester tanks recognized for its environmental management system RECLAIMED WATER ‘Saving H 0’ where anaerobic bacteria at 98 degrees Fahrenheit • Most (90 percent) of secondary sludge 2 break down organic material and kill pathogens. and commitment to continual improvement. goes back to the aeration tanks to keep a • After disinfection, some secondary effluent undergoes advanced treatment (coagulation, filtration, The activity of the bacteria creates digester gas healthy bacteria population going; the rest and reduces the solids mass by 50 percent. goes to the solids handling process. disinfection) to reduce use of water for irrigation and some plant processes. • The remaining water — secondary effluent — leaves Department of Natural Resources and Parks Wastewater Treatment Division the clarifiers at least 85 percent cleaner, typically www.kingcounty.gov/wtd close to 95 percent, than when it entered West Point. 206-684-1280