1921 Argonne Dr, Walnut Creek, CA 94598 Property Records

Contra Costa County property record for 1921 Argonne Dr, Walnut Creek, CA 94598

Property Summary

Property Type	Single Family Home
Details	3 bd · 2.5 ba · 2,030 sqft · built 1969
Lot Size	0.251 acres (10,925 sqft)
Owner	Individual Name on Record
Last Sale	$939,000 (Oct 2020)
Tax Bill	$12,027 (2025)
Deeds & Mortgages	Oct 2020 Sale & Mortgage
Flood Zone	Zone X (minimal risk)
APN	`145-045-009-1`

Property Details

APN / Parcel Number

Primary APN	`145-045-009-1`
Alternative APN	`145-045-009`

Interior

Bedrooms	3 Beds
Full Baths	2.5 Baths
Half Baths	1 Half Bath
Total Rooms	9 Rooms
Stories	1 Story
Building Area	2,030 sqft Living Area
1st Floor Area	1,608 sqft
Basement Area	422 sqft

Exterior

Year Built	Built 1969
Effective Year Built	Effective 1985
Lot Area	10,925 sqft (0.251 acres)
Garage Type	Attached
Garage Area	457 sqft
Parking Spaces	2 Parking Spaces

Utilities, Heating & Cooling

Cooling System	Central

Location & Zoning

Street Address	1921 ARGONNE DR
City	WALNUT CREEK
State	CA
Zip	94598-1204
Property Category	Residential
Property Type	Residential > Single Family > Home
Local Zoning Code	R10
Legal Description	TRACT 3740 LOT 55 EX MR
Legal Subdivision	SUBDIVISION 3740
Legal Tract	3740
Legal Lot Number	55
Jurisdiction	CONTRA COSTA CA
Township / Civil Division	CENTRAL CONTRA COSTA
Census Block Group	1
Census Block	1014
Census Tract	338201

Owner

Source: Contra Costa County records, as of July 14, 2026

Owner names and exact recorded amounts shown locked on this page are available instantly with a free trial.

Owner of Record	Individual Name on Record
Mailing Address	1921 ARGONNE DR, WALNUT CREEK, CA 94598-1204
Occupancy	Owner Occupied
Owner Type	Individual

Deeds, Mortgages & Sale History

Assessor's Deed Record

Deed Names	Name on Deed
Last Sale	Oct 6, 2020 · Amount on Record
Deed Sale	Oct 6, 2020 · Amount on Record
Prior Sale	Mar 31, 2016 · Amount on Record
Deed Document Number	2020228161
Record Updated	Oct 29, 2026

October 2020: Grant Deed, Transfer

Document Type	Grant Deed
Jurisdiction	CONTRA COSTA CA
Recording Date	Oct 6, 2020
Property Address	1921 ARGONNE DR, WALNUT CREEK, CA 94598-1204
Document Number	0000228161
Map Reference	MB 121 PG 19
Instrument Date	Oct 2, 2020
Instrument	2020-228161
Transaction Type	Transfer
Record Updated	Nov 3, 2022
Title Company	FIDELITY NATIONAL TITLE CO

Transaction

Amount	Amount Recorded
Downpayment	Downpayment on Record
Loan-to-Value (LTV)	LTV on Record
Tax	$0.00
Amount Accuracy	Rounded by County
Additional	Arm's Length

Transferred From (Grantor/Seller)

Name	Verified Name

Transferred To (Grantee/Buyer)

Name	Verified Name
Address	1921 ARGONNE DR, WALNUT CREEK, CA 94598-1204

Mortgage

Document Number	0000228162
Date	Oct 6, 2020
Instrument	2020-228162

Lender

Name	UNITED WHOLESALE MORTGAGE
Type	Mortgage Company

Agreement

Type	Conventional Mortgage
Amount	Amount Recorded
Term	361 Months
Due	Nov 1, 2050

Tax Assessment & Valuation

Source: Contra Costa County assessment roll, as of July 14, 2026

Property Jurisdictions

Type	Name
State	California
County	Contra Costa County
Municipality	Walnut Creek City
Unified School District	Mount Diablo Unified School District (KG - 12)

Tax Bill & Assessment History

Year	Tax Bill	Assessed Value
2026		$1,036,729 (+2%) Land $705,506 Building $331,223
2025	$12,027.00 (+4.05%) Homeowner's exemption	$1,016,402 (+4.04%) Land $691,673 Building $324,729
2023	$11,559.00 (+0.88%) Homeowner's exemption	$976,935 Land $664,815 Building $312,120
2022	$11,458.00

Assessed value is set for property tax purposes and is not a market price estimate.

Flood

Source: FEMA National Flood Hazard Layer, effective October 12, 2026 · OpenFEMA NFIP redacted claims and policies, as of September 2026

FEMA Flood Zone	Zone X minimal risk
Nearest Special Flood Hazard Area	Zone AE, within 500 ft
Flood Insurance Requirement	Not required lenders may require it
Community Rating System	Class 7 (15% premium discount)
Nearby Flood Policies	9 in force
Nearby Flood Claims	1 (1982)
Most Recent Claim	Jan 1982 · Severe Storms, Flood, Mudslides & High Tide

Values are read at the parcel center point; flood claims are located to the census block group, not this parcel; lenders make the official flood determination.

Wildfire

Source: USDA Forest Service Wildfire Risk to Communities (2nd edition), as of 2024

Wildfire Risk	Low lower than 99.1% of the US · lower than 99.2% of California
Wildfire Likelihood	Under 0.01% annual chance
Exposure	None beyond ember reach

Values cover an area roughly 900 ft across, not the parcel itself; insurers use their own ratings.

Drinking Water

Source: EPA Safe Drinking Water Information System, as of September 2026

Water System	CONTRA COSTA WATER DISTRICT serves 210,500 people · EPA ID CA0710003
Water Source	Surface water
Last State Inspection	Jan 2022
Lead	Under 1 ppb (2026–2028) action level 15 ppb

Violations Reported to EPA

Water Quality	None last 10 years
Treatment and Procedure	None last 10 years
Monitoring and Reporting	None last 3 years

Results are for the whole water system, not water tested at this address; lead at the tap also depends on the building's own pipes.

Internet Providers

Source: FCC Broadband Data Collection, based on 406 locations within half a mile, as of December 31, 2025

Provider	Max Down / Up (Mbps)
Xfinity Cable	2,000 / 250
Astound Broadband Cable	1,500 / 50
Unwired Fixed Wireless	300 / 25
Verizon Fixed Wireless	300 / 20
AT&T Fixed Wireless · DSL	100 / 20