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King County Department of Assessments

Setting values, serving the community, and promoting fairness and equity.

Department of Assessments

201 South Jackson Street,
Seattle, WA 98104

Office Hours:
Mon - Fri
8:30 a.m. to 4:30 p.m.

TEL: 206-296-7300
TTY relay: 711 or 800-833-4388

Send us mail

 
PARCEL DATA
Parcel242304-9006
NameKING COUNTY-WASTE WATER
Site Address1200 MONSTER RD SW
Geo Area 70-10
Spec Area
Property NameMETRO TREATMENT PLANT
JurisdictionRENTON
Levy Code2100
Property Type C
Plat Block / Building Number
Plat Lot / Unit Number
Quarter-Section-Township-Range NW-24-23-4
Legal Description
PER RENTON DECLARATION OF LOT COMBINATION #18-000597 REC# 20190228900013 SD LOT COMBO BEING POR NW 1/4 & POR W 1/2 OF NE 1/4 STR 24-23-4
PLat Block:
Plat Lot:


LAND DATA
 
Highest & Best Use As If VacantMANUFACTURING
Highest & Best Use As Improved(unknown)
Present UseUtility, Public
Land SqFt3,151,155
Acres72.34
Percentage Unusable 
UnbuildableNO
Restrictive Size ShapeNO
ZoningIH
WaterWATER DISTRICT
Sewer/SepticPUBLIC
Road AccessPUBLIC
ParkingADEQUATE
Street SurfacePAVED
Views Waterfront
Rainier
Territorial
Olympics
Cascades
Seattle Skyline
Puget Sound
Lake Washington
Lake Sammamish
Lake/River/Creek
Other View
Waterfront Location
Waterfront Footage0
Lot Depth Factor0
Waterfront Bank
Tide/Shore
Waterfront Restricted Access
Waterfront Access RightsNO
Poor QualityNO
Proximity InfluenceNO
Designations Nuisances
Historic Site
Current Use(none)
Nbr Bldg Sites 
Adjacent to Golf FairwayNO
Adjacent to GreenbeltNO
Other DesignationNO
Deed RestrictionsNO
Development Rights PurchasedNO
EasementsNO
Native Growth Protection EasementNO
DNR LeaseNO
 
Topography
Traffic Noise
Airport Noise 
Power LinesNO
Other NuisancesNO
Problems
Water ProblemsNO
Transportation ConcurrencyNO
Other ProblemsNO
Environmental
EnvironmentalNO

BUILDING
Building Number1
Building DescriptionPUMP HOUSE
Number Of Buildings Aggregated1
Predominant UseLIGHT COMMERCIAL UTILITY BUILDING (471)
ShapeRect or Slight Irreg
Construction ClassMASONRY
Building QualityAVERAGE
Stories1
Building Gross Sq Ft10,662
Building Net Sq Ft10,662
Year Built1998
Eff. Year2010
Percentage Complete100
Heating SystemNO HEAT
Sprinklers 
Elevators 
1234
Click the camera to see more pictures.
Picture of Building 1
Current Picture
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Floor plan of Building 1
Current Picture
Section(s) Of Building Number: 1
Section NumberSection UseDescriptionStoriesHeightFloor NumberGross Sq FtNet Sq Ft
1 LIGHT COMMERCIAL UTILITY BUILDING (471) 1100 10,66210,662

Accessory
Accessory TypePictureDescriptionQtyUnit Of MeasureSizeGradeEff Yr%ValueDate Valued
Miscellaneous All Imps except bldgs.   (unknown)  904080012/7/1998
Miscellaneous Treatment below ground imps.   (unknown)  309781003/16/2009
 





TAX ROLL HISTORY

This is a government owned parcel.
Change to state law (RCW 84. 40.045 and 84.40.175) by the 2013 Legislature eliminated revaluation of government owned parcels.

SALES HISTORY


REVIEW HISTORY


PERMIT HISTORY

Permit NumberPermit DescriptionTypeIssue DatePermit ValueIssuing JurisdictionReviewed Date
M26002389 Remove the failing lining in the plant´┐¢s influent division channel conduct surface repairs and surface preparation as needed install new coatings and replace approx. 50 LF of 8" HDPE DR 17 pipe and fittings. In addition the project will involve, Other5/11/2026$2,165,122RENTON7/28/2026
M26002166 Installation and replacement of key components of the Biogas system at the South Treatment Plant (STP) in Renton WA. The work of the contract includes but is not limited to replacement of the gas dehydration system waste gas burners scrubbing w, Other4/28/2026$2,500,000RENTON7/28/2026
B25006207 KING COUNTY WASTEWATER TREATMENT PLANT DAFT REHAB PROJECT- REPLACEMENT OF WASTEWATER TREATMENT EQUIPMENT, Remodel4/27/2026$1,283,190RENTON7/28/2026
B25006427 KING COUNTY WASTEWATER DIVISION- SOUTH WASTEWATER TREATMENT PLANT DIVISION CHANNEL RECOATING PROJECT., Remodel2/26/2026$1,290,168RENTON7/28/2026
E26000766 Remove and replace 6 large UPS systems ranging from 30KVA to 80KVA.,  2/12/2026$275,000RENTON7/28/2026
E26000731 Install 2 post rack and ladder trap is server room install tie cabling from new 2 post rack to server cabinet 1 & 2,  2/11/2026$26,000RENTON7/28/2026
M26000048 The purpose of the project is to replace an aging 400kW essential service standby generator generator replacement panel and associated accessories and circuiting. The project also includes the replacement of existing non-functional underground fue, Other1/6/2026$1,395,761RENTON7/28/2026
E25006437 King County South Treatment Plant Essential Services Standby Generator Replacement. Replace existing Generator Fuel Detection and MCC.,  12/30/2025$355,888RENTON7/28/2026
E25004672 King County Metro South Treatment Plant EV Charging Stations. Installation of 5 electrical vehicle chargers. Includes installing transformers and panelboard. NOTE: Attachment was not reviewed for approval and is for reference only. SEPARATE BUIDING,  12/18/2025$108,258RENTON7/28/2026
E25005811 Building fire alarm system tenant improvement.,  12/11/2025$2,710RENTON7/28/2026
M25004015 KING COUNTY WASTEWATER TRUCK BAY VENTILATION SYSTEM. Install roof top air Handling Unit and ductwork. Not heating or cooling., Other12/9/2025$122,500RENTON7/28/2026
B24006475 KING COUNTY TREATMENT PLANT GAS BURNER EQUIPMENT PADS. NEW EQUIPMENT PADS IN EXISTING WASTE GAS BURNER ENCLOSURE, Remodel11/7/2025$109,318RENTON7/28/2026
B24006473 KING COUNTY SOUTH TREATMENT PLANT GAS DRYER CANOPY. NEW PREFABRICATED METAL CANOPY OVER GAS DRYERS, Remodel11/7/2025$64,305RENTON7/28/2026
B24006469 KING COUNTY SOUTH TREATMENT PLANT THERMAL OXIDIZER PAD. NEW EQUIPMENT SLAB FOR NEW FLASH VESSEL AND THERMAL OXIDIZER., Remodel11/7/2025$214,779RENTON7/28/2026
B24005505 KING COUNTY WASTE WATER TREATMNT SOUTH PLANT. REPLACEMENT OF ESSENTIAL SERVICES GENERATOR AT THE SOUTH TREATMENT PLANT., Remodel10/10/2025$1,960,000RENTON7/28/2026
E25004672 South Treatment Plant EV Charging Stations. Installation of 5 electrical vehicle chargers. Includes installing transformers and panelboard. NOTE: Attachment was not reviewed for approval and is for reference only.,  9/15/2025$108,258RENTON7/28/2026
E25004478 Installation of pathway and wire for two VFD/AHU units,  9/4/2025$15,000RENTON7/28/2026
B25001571 KING COUNTY WASTEWATER TREATMENT PLANT - INSTALL 5 ELECTRICAL VEHICLE PEDESTAL CHARGERS, Remodel5/15/2025$93,000RENTON7/9/2025
B25001076 KING COUNTY WASTEWATER TREATMENT PLANT- GATE FRAME/SAFETY STAIR INSTALL (DIVISION CHANNEL), Remodel4/14/2025$20,000RENTON7/9/2025
B25001122 KING COUNTY SOUTH TREATMENT PLANT SAFETY GATE SYSTEM, Remodel4/11/2025$50,000RENTON7/9/2025
E25000444 Replace 2 pumps,  1/28/2025$16,000RENTON5/14/2025
B24004966 PATCHING OF CORRODED CONCRETE UNDER FOUL AIR DUCTS MODIFICATION AND REAPLCEMENT OF EXISTING FLOOR-LEVEL COVER PANELS REPLACING 2 TON MONORAIL TROLLEY HOIST SYSTEM REPLACING AGED STOP-LOG GATES., Remodel12/4/2024$365,000RENTON7/9/2025
E24004944 King County South Treatment Plant EPA BRRR Compliance. Install 3 flow meters and the associated instrumentation and control wiring.,  10/31/2024$90,000RENTON5/14/2025
B24003157 King County Loop Compost Project 60'x39' fabric canopy structure, Remodel9/25/2024$95,520RENTON5/14/2025
E24004163 Add ammonium and nitrate probes to the secondary aeration tanks at King County's South Treatment Plant Note: No plan review required based on description of work and/or fixtures selected. Attachment was not reviewed for approval and is for reference  8/23/2024$262,900RENTON5/1/2025
E23006085 King County South Treatment Plant Siloxane Removal System. Add controls and instrumentation to new siloxane removal system. Integration of new controls into existing PLC.,  1/11/2024$52,220RENTON7/2/2024
B23001945 MAKE IMPROVEMENTS TO TRUCK LOADING BAY AREA VENTILATION SYSTEM. OWNER ACTING AS CONTRACTOR., Remodel12/21/2023$869,575RENTON7/9/2025
E23005667 King County Wastewater Treatment Plant. Install an interim alkalinity feed system consisting of a new alkalinity tank pump skid system and associated components. NOTE: No plan review required based on description of work. Attachment was not reviewed  11/16/2023$300,000RENTON7/2/2024
B22006463 K.C. WASTE WATER TREATMENT PLANT- MODIFY THE HVAC SYSTEM IN COMPUTER ROOM REPLACE EXISTING HALON FIRE SUPPRESSION SYTEMS WITH A HALO CARBON GAS (TOTAL FLOODING SYSTEM) ADD NEW SMOKE DETECTORS INCLUDING EARLY WARNING SMOKE DETECTION ALARMS MODIFY COMPRemodel9/29/2023$151,728RENTON7/9/2025
B23003539 DEMOLITION AND INSTALLATION OF NEW CONCRETE PADS FOR MECHANICAL EQUIPMENT, Remodel9/14/2023$8,700RENTON5/1/2025
B23003956 REMOVE SELECT EXISTING GATE FRAMES AND INSTALL FOUR NEW BOLT-IN GATE FRAMES. SOUTH PLANT DIVISION CHANNEL., Remodel8/18/2023$758,105RENTON5/1/2025
E23003957 KING COUNTY SOUTH TREATMENT PLANT T.I. - LOW VOLTAGE ELECTRICAL FOR FIRE ALARM SYSTEM UPDATES. NOTE: No work shall be started without issuance of the required associated fire permit.,  8/1/2023$309,802RENTON7/2/2024
B23003044 REHABILITATE AN EXISTING LIQUID CHEMICAL FEED SYSTEM BY INSTALLING A NEW ABOVE GRADE STORAGE TANK & ANCHORAGE CHEMICAL FEED PUMPS AND ASSOCIATED PIPING., Remodel6/27/2023$270,000RENTON5/1/2025
E23002767 Remove existing electrical and controls for odor control pumps. Install new electrical and controls for new odor control pump skid,  5/25/2023$40,000RENTON7/26/2023
B22005232 REPLACEMENT OF EQUIPMENT WEIGHING 32400 LBS ON EXISTING STRUCTURAL CONCRETE PAD., Remodel11/14/2022$550,000RENTON7/2/2024
E22004668 South Treatment Plant Heating Systems Improvements. Upgrades to the existing plant's hot water system. Demo of existing system and install of new circ pumps heat exchangers heat extractors and all associated controls. No plan review required based on 9/12/2022$2,000,000RENTON5/1/2025
M22004651 Tenant improvement involves the installation of siloxane scrubbers., Other8/31/2022$665,562RENTON7/2/2024
P22003957 This measure provides a siloxane polisher at the end of the bio-methane cleaning process pipeline to remove siloxane. NOTE: No plan review required based on description of work. Attachment was not reviewed for approval and is for reference only.,  7/27/2022$225,000RENTON7/2/2024
B22001349 KING COUNTY WASTEWATER TREATMENT DIVISION CONCRETE PAD. DEMOLITION OF EXISTING CONCRETE PAD AND CONSTRUCTION OF NEW CONCRETE PAD., Remodel7/26/2022$45,000RENTON5/11/2023
E22002692 Install new water softener system,  5/23/2022$8,000RENTON7/8/2022
M22001181 INSTALL GAS PIPING FOR THE Upgrade size of existing 500 gallon propane tank to 1000 gallon tank to meet business needs. Requires installation of temporary 500 gallon propane tank removal of existing 500 gallon tank demo of existing concrete pad and cOther3/10/2022$450,000RENTON5/11/2023
P22000830 Connect P Trap and faucet on (1) sink,  2/18/2022$800RENTON7/8/2022
E22000556 low voltage for fire suppression release panel and controls replacement. NOTE: No plan review required based on description of work. Attachment was not reviewed for approval and is for reference only.,  2/3/2022$2,100RENTON7/8/2022
B21006171 The King County Wastewater Treatment Division proposes to replace the roof of the existing South Treatment Plant Electrical Substation Secondary Facility located within King County Parcel 2423049006 at 1200 Monster Road SW Renton 98057. The new roof Remodel1/12/2022$18,000RENTON7/26/2023
E22000045 relocate duplex receptacle move power for projector and motor screen.,  1/4/2022$2,000RENTON7/8/2022
B19006697 DEMOLISH FUEL CELL, Demolition11/15/2021$320,000RENTON5/11/2023
B19006693 KC SOUTH TREATMENT PLANT FUEL CELL DEMO, Demolition11/15/2021$320,000RENTON7/8/2022
M21004584 Anchor Bolts, Other9/27/2021$500RENTON5/11/2023
E21004416 Low Voltage permit Installation of Cat 6 and fiber optic cables,  9/13/2021$12,000RENTON7/8/2022
B21002996 INTERIOR REMODEL OF TRAINING ROOM IN ADMINISTRATION BUILDING. REMOVE NON-LOAD BEARING PARTITION WALL. REPLACE SINK COUNTERTOP AND BACK SPLASH. RELOCATE ELECTRICAL AND DATA., Remodel9/8/2021$50,000RENTON7/8/2022
E21002009 Add new heat trace and GFCI circuit,  5/5/2021$17,065RENTON7/7/2021
E20005235 KING COUNTY WASTE SOUTH FIRE ALARM- ADD 50 DEVICES TO EXISTING,  11/24/2020$1,000RENTON7/7/2021
E20004834 R&R 1 ea. fuel dispenser using existing conduit and wire,  10/20/2020$1,600RENTON7/7/2021
E20001726 Replacing the Cathodic Protection System on 2 underground Storage Tanks located at South Plant Treatment,  4/24/2020$70,000RENTON7/1/2020
B19003810 REPAIR/RETROFIT EXISTING SKYBRIDGE AND PIPE CHASE THAT CONNECTS TO DIGESTER 2 ROOF TO THE BLENDED STORAGE TANK ROOF. PLATES AND ANCHORS BOLTS WILL BE ATTACHED TO THE EXISTING BRIDGE GIRDERS TO PROVIDE RE-ENFORCEMENT AND RESTORE BEARING CAPACITY. SHORRemodel10/9/2019$48,833RENTON7/1/2020
B18005622 MODIFY RAILING AROUND AERATION POND AND INSTALL PLATFORM AND LADDER SUPPORT STRUCTURE TO PROVIDE SAFER MAINTENANCE ACCESS TO THE AERATION POND., Remodel11/14/2018$737,000RENTON6/19/2019
P17005277 KING COUNTY- PLUMBING FOR NEW WATER RECLAIM STRUCTURE- 4 FIX AND (2) EYE WASH STATIONS,  11/8/2017$250,000RENTON5/16/2019
B16006588 DEMOLISH EXISTING 168 SQUARE FOOT WATER RECLAIM STRUCTURE AND BUILD NEW 363 SQUARE FOOT WATER RECLAIM STRUCTURE. REPLACES B16006041. DEMOLITION TO BE COMPLETED BEFORE FRAMING INSPECTION., Remodel1/23/2017$250,000RENTON5/16/2019
M120262 KC WASTEWATER PLANT-NEW ROOFTOP AHU, Remodel7/9/2012$66,750RENTON5/16/2019
B120214 CONCRETE PADS FOR STORAGE TANK FOR KING COUNTY WASTEWATER TREATMENT PLANT, Remodel6/26/2012$55,000RENTON5/16/2019
B120109 SOUTH POINT TREATMENT PLANT-INSTALL TWO (2) CONCRETE MOUNTING PADS ON EXISTING CONCRETE SLAB TO MOUNT REPLACEMENT BLOWERS, Remodel4/6/2012$11,000RENTON5/16/2019
B090197 Demo (7) attached modular buildings.Demolition5/27/2009$0RENTON5/16/2019
B080483 K.C. S treatment - sodium Hypoclorite disinfection system.Other10/17/2008$2,750,000RENTON5/16/2019
B070465 Install temporary trailer during construction of A.Accessory, New9/27/2007$400,000RENTON5/16/2019
B060459 Construct new admin bldg. for Metro.Building, New12/29/2006$1,829,452RENTON5/16/2019
B050632 Other1/25/2006$2,300,000RENTON5/16/2019
B030606 Building, New6/9/2004$2,200,000RENTON5/16/2019
B030176 Other9/4/2003$550,000RENTON5/16/2019
B020640 Building, New3/14/2003$5,030,000RENTON5/16/2019
B990441 NoneBuilding, New10/5/1999$17,000RENTON5/16/2019

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