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Washington · Tri-Cities · Columbia River · Hanford Nuclear Site
Benton County, Washington
The Tri-Cities and Hanford's nuclear legacy — from the Hanford Site's massive nuclear cleanup project (the most contaminated nuclear site in the Western Hemisphere, where plutonium for the Trinity test and the Nagasaki bomb was produced) to the Columbia River's wine country corridor, Richland's atomic heritage, and a southeastern Washington community whose entire mid-20th century identity was built around the secret city of nuclear production.
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Benton County's assessment ratio means effective tax rates are low — but incorrect appraisals still cost money. Ownwell manages the appeal with no upfront cost.
Notes: Coordinates with Hanford Site planning given the county’s decades-long role protecting and overseeing use of the Hanford Reach and surrounding National Monument lands.
Roads & Utilities
ROADS & TRANSPORTATION
Roads: I-82 and US-395/US-12 are primary corridors; the county spans the Tri-Cities metro area
Transit: Ben Franklin Transit provides regional bus service across Benton and Franklin counties
Business & Permits
BUILDING & PERMITS
Office: Benton County Building Division – Benton County Public Services Building, 102206 E. Wiser Parkway, Kennewick, WA 99338 | Kennewick: (509) 735-3500 | Prosser: (509) 786-5622 | Hours: Monday–Friday 8 AM–12 PM and 1 PM–5 PM
Services: Administers the State Building Code Act and Benton County Code for unincorporated county areas only; permit electronic submittal via [email protected]
Notes: Effective September 3, 2024, Benton County now requires 3rd-party plan review and inspections for Energy Code compliance on all new commercial/industrial projects. Inspection requests go to a dedicated 24/7 line, (509) 736-2763, with a minimum 24-hour advance notice required; requests called in Friday after 4 PM are performed within 2 working days. Road approach permits are required from Benton County Public Works – (509) 786-5611 (Prosser) or (509) 736-3084 (Tri-Cities) – or WSDOT for state road approaches. Access roads/private driveways over 150 feet long and over 12% grade must be paved; grades over 15% are not permitted under Benton County Code 3.18.045. Note the incorporated Cities of Kennewick, Richland, and Prosser each maintain their own separate building departments – confirm jurisdiction before applying to the county.
Veterans Services
VETERANS SERVICES
State VSO: Washington State Department of Veterans Affairs – dva.wa.gov (statewide office locator for the nearest County Veterans Service Officer)
Notes: Confirm current local point of contact directly with dva.wa.gov.
Libraries
LIBRARIES
System: Mid-Columbia Libraries – founded 1948, serves the Tri-Cities metro area (except Richland, which retains its own separate city library) plus surrounding Benton, Franklin, and parts of Adams counties, covering roughly 270,000 residents; Kennewick, Benton City, Connell, Mesa, and Kahlotus have annexed into the district, while Pasco, West Richland, and Prosser hold service contracts with the district
Notes: This is a genuinely broad, multi-jurisdiction regional library district – confirm which specific branch and hours apply to your location, as the annexation/contract structure varies by city.
Parks & Recreation
PARKS & RECREATION
Key Assets: Benton County holds genuinely momentous 20th-century American history – the Hanford Site, established in 1943 as part of the Manhattan Project, was home to the world’s first full-scale plutonium production reactor (B Reactor); plutonium manufactured at Hanford was used in the Trinity nuclear test and in the “Fat Man” bomb dropped on Nagasaki, Japan, on August 9, 1945; during the Cold War the site expanded to 9 nuclear reactors and 5 plutonium processing complexes, producing material for the majority of the more than 60,000 weapons in the U.S. nuclear arsenal; the B Reactor is now part of the Manhattan Project National Historical Park (established November 2015, spanning Hanford WA, Los Alamos NM, and Oak Ridge TN) and is open for public tours; the surrounding Hanford Reach National Monument preserves the land and river along the site; separately, Benton County is a major Washington wine region, home to the Red Mountain AVA (entirely within the county) and portions of the Horse Heaven Hills and Yakima Valley AVAs (the latter being the first American Viticultural Area established in Washington State, in 1983); the county was originally formed March 8, 1905, centered on agriculture due to superior irrigation systems before the Manhattan Project’s arrival shifted the regional economy toward technology and nuclear industry
Notes: This is genuinely one of the most historically consequential sites in modern American history – not incidental local color – directly connected to the end of World War II and the subsequent nuclear arms race.
GIS & Maps
GIS & MAPS
GIS Portal: Benton County GIS – accessible via bentoncountywa.gov
Parcel Search: Benton County Assessor’s records
Addressing/911: Coordinated through Benton County Emergency Management
Animal Services
ANIMAL SERVICES
Facility: Benton County Canine Shelter – 1116 N. Grant Place, Kennewick, WA 99336 | (509) 460-4923 | Email: [email protected]
Hours: Monday–Saturday 10:00 AM–5:00 PM, closed Sunday; arrive between 11 AM–4 PM to allow adequate time to visit dogs
Services: Shelter, safety, and adoption placement for stray, abandoned, and neglected dogs within unincorporated Benton County
Notes: IMPORTANT – this shelter serves DOGS ONLY and covers UNINCORPORATED county areas only. Strays found within unincorporated Benton County must be reported to the shelter within 3 business days if you choose to temporarily care for them yourself. Dogs found within incorporated cities (Kennewick, Richland, etc.) must be reported to that specific city’s own animal control program instead – do NOT bring city-found strays to the county shelter. The separate, independent nonprofit Benton-Franklin Humane Society, established 1966, 1736 E 7th Ave, Kennewick, WA 99337, (509) 374-4235, is the Tri-Cities’ only no-kill shelter, caring for owner-surrendered pets (including cats) and receiving no government funding – a genuinely important distinction since the county shelter is dogs-only and government-run.
Environmental & Waste
ENVIRONMENTAL / WASTE MANAGEMENT
Environmental Complaints: Washington State Department of Ecology – ecology.wa.gov
Notes: Contact Benton County Public Works directly for current refuse collection and recycling program details.
NOTES
Benton County holds genuinely momentous 20th-century American history at the Hanford Site – the birthplace of the world’s first full-scale plutonium production reactor, directly tied to the end of World War II and now preserved as part of the Manhattan Project National Historical Park. The county’s animal welfare system splits cleanly between a dogs-only, government-run county shelter for unincorporated areas and the independent, no-kill Benton-Franklin Humane Society, which also accepts cats – know which one applies to your situation before assuming coverage. All contact information above was sourced from official county and National Park Service pages as of this writing; phone numbers and hours should be reconfirmed directly with the relevant office before a visit.
About Benton County
Benton County is southeast Washington’s Hanford nuclear legacy and Columbia Valley wine country county – the massive federal nuclear cleanup site that defines Richland’s identity and the world-class wine vineyards of the Horse Heaven Hills together create one of Washington’s most economically distinctive counties at the heart of the fast-growing Tri-Cities metro.
Prosser (the county seat, population ~6,200) is Benton County’s governmental hub and wine country center while Richland, Kennewick, and the broader Tri-Cities metro drive the county’s population and economic growth along the Columbia River.
All Services
Browse every category and topic available for this county.
Washington assesses at 100% of true and fair market value. The Benton County Assessor at 620 Market Street, Prosser, WA 99350, phone 509-786-5600, conducts assessments. Appeal to the Benton County Board of Equalization by July 1. WA estate tax applies over $2.193M. No WA inheritance tax.
Recommended
Benton County Board of Equalization appeal: July 1. Tri-Cities has seen consistent appreciation from Hanford cleanup employment and regional growth. No WA inheritance tax. Ownwell manages the appeal with no upfront cost.
Courts & Legal
Benton County Superior Court (Probate) at 7122 W. Okanogan Place, Building A, Kennewick, WA 99336, phone 509-736-3071, handles probate. Auditor’s Office at 620 Market Street, Prosser, maintains deed records.
Marriage & Vital Records
Marriage licenses, divorce records, and birth & death certificates are handled by the following office(s):
COUNTY CLERK
7122 West Okanogan Pl, Kennewick, WA 99336
(509) 735-8476
Genealogy
County-level record sources
Benton County Superior Court Clerk’s Office, Kennewick (probate/estate case files – see Probate section above).
Southeast Regional Branch of the Washington State Archives, at Washington State University Tri-Cities, serves counties in this region.
Local societies
No dedicated Benton County genealogical society was confirmed in available directories.
Probate & Estate
Losing someone and having to deal with courts and paperwork at the same time is hard. This section won’t make that easier, but it should tell you what to expect, what it costs, and where to go – so at least you’re not walking in blind.
Where to go
Benton County Superior Court 7122 West Okanogan Place, Building A, Kennewick, WA 99336 (509) 736-3071
Benton County is in South Central Washington’s Tri-Cities region, county seat Prosecutor’s office in Kennewick. Washington has NO separate probate court and has NOT adopted the Uniform Probate Code – probate is handled through the Superior Court in each county, under Title 11 RCW.
Step 1: figure out which path applies
Washington probate is entirely discretionary – the law does not require a probate proceeding to be filed after a death, regardless of whether there was a will. Probate is typically pursued only when the decedent owned real property titled solely in their name, or personal property exceeding the small estate threshold.
Small Estate Affidavit (RCW 11.62.010) – available when the decedent’s entire probate estate does not exceed $100,000 (personal property only, not counting the surviving spouse’s community property interest), and at least 40 days have passed since death. No court filing is required – the successor presents the sworn affidavit directly to whoever holds the asset. All debts must be paid or provided for first.
Nonintervention Powers (RCW 11.68) – Washington’s signature alternative to full court-supervised probate. If the estate is solvent, the Superior Court MUST grant the personal representative nonintervention powers upon request (unless the will specifically forbids it). Once granted, the representative can sell, mortgage, and distribute estate property, and ultimately close the estate by filing a Declaration of Completion – all without further court orders, notice to beneficiaries, or hearings.
Full/Supervised Administration – required only when nonintervention powers are denied or not sought, typically in contested or insolvent estates.
TEDRA (Trust and Estate Dispute Resolution Act, RCW 11.96A) – Washington’s framework for resolving probate, trust, and estate disputes.
Step 2: filing for administration
The person seeking to serve as personal representative files a petition with the Benton County Superior Court Clerk’s Office, along with the original will (if any) and a certified death certificate.
The court appoints the personal representative and issues Letters Testamentary (with a will) or Letters of Administration (without one).
The personal representative petitions for nonintervention powers, which the court must grant if the estate is solvent (unless the will forbids it).
Once granted, the representative pays debts, manages and distributes property, and notifies creditors, without further court supervision.
The estate is closed by filing a Declaration of Completion.
What it costs
Filing fees and probate costs vary by estate complexity; confirm current Benton County Superior Court fees directly.
Washington HAS a state estate tax, separate from any small estate affidavit or nonintervention process. For deaths on or after July 1, 2026, the applicable exclusion amount is $3,000,000 (RCW 83.100.020), with rates from 10% to 20%. There is NO portability between spouses.
The federal estate tax exemption is far higher, at $15,000,000 for a 2026 death.
Probate filings, estate administration, and guardianship matters are handled by the following office(s):
Public Safety & Arrests
Arrest records, inmate search, and law enforcement services are handled by the following office(s):
SHERIFF
7122 West Okanogan Pl, Kennewick, WA 99336
(509) 735-6555
Elections & Voting
Voter registration, polling locations, and elections information are handled by the following office(s):
ELECTIONS
620 Market St, Prosser, WA 99350
(509) 786-2019
Health & Human Services
Offices & Contacts
Health services, social services, and assistance programs are handled by the following office(s):
Health District
Benton-Franklin Health District, 7102 West Okanogan Pl, Kennewick, WA 99336
(509) 460-4200
DSHS Community Services Office
825 Jadwin Ave, Richland, WA 99352
(509) 372-2500
Public Health Information
PUBLIC HEALTH
Office: Benton-Franklin Health District – serves both Benton and Franklin counties jointly
Services: Immunizations, WIC, environmental health, vital records
Notes: Confirm current hours and services directly.
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Recommended for Washington
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