Commercial Real Estate in Kelseyville: Main Street, Highway 29, Lampson Field and County Zoning

By Matthew Martinez, Founder, CEO & Managing Broker, Diamond Real Estate Group. California DRE #01869679.

Kelseyville is an unincorporated farm town in Big Valley, between Clear Lake and Mount Konocti, south of Lakeport. Its commercial property centers on Main Street. Service and industrial uses sit along Kelsey Creek, Live Oak Drive and Renfro Drive and near Lampson Field, and highway-oriented sites line Highway 29. Vineyards and orchards surround the town. Lake County controls zoning here, and each parcel’s district and sewer status must be confirmed with Community Development.

Who controls the parcel

Land use: Lake County, under the zoning ordinance and the Kelseyville Area Plan. The plan covers Kelseyville, Finley, Big Valley and surrounding rural land. Its citizens’ advisory committee was appointed in October 1989, so check with the county for any later amendments.
Water and sewer: The plan identifies Kelseyville County Waterworks District No. 3 as the town’s water provider (about 854 connections) and sewer provider (about 1,050 connections in town plus 68 at Corinthian Bay and the state park). Its treatment plant capacity is listed at 260,000 gallons per day. Finley water comes from County Service Area 6. Sewage from Finley and Land’s End/Holiday Cove goes through a county sanitation assessment district to the City of Lakeport’s plant. Other areas use septic systems.
Fire: Lake LAFCo’s 2025 fire review lists the Kelseyville Fire Protection District headquarters as Station 55 at 4020 Main Street, with Station 56 on Soda Bay Road. The district covers about 90 to 100 square miles, including Soda Bay and the Rivieras. It sits in high and very high fire hazard severity zones, has an ISO rating of 4/4Y, and the review found its water system inadequate for fire protection.
Airport: Lampson Field, about three miles south of Lakeport off Highland Springs Road, falls under the county’s 2007 Airport Land Use Compatibility Plan.

Kelseyville zoning for commercial, industrial and agricultural business

District	Intended uses	Notes
C2 Community Commercial	Main Street retail, restaurants, offices; upper-floor housing	By right: enclosed, up to 5,000 sq ft per use, 6 a.m. to midnight, no drive-thru. Retail cannabis by minor permit
C1 Local Commercial	Small neighborhood retail	By right up to 2,000 sq ft, 6 a.m. to 10 p.m.
CH Highway Commercial	Traveler services at highway intersections	Restaurants including drive-thru by right up to 3,000 sq ft
C3 Service Commercial	Service and heavier commercial	Kelsey Creek, Live Oak Drive, Lampson Field area
M1 Commercial/Manufacturing	Heavy commercial and light manufacturing	South of Lampson Field, Renfro Drive, Kelsey Creek north of Merritt Road
AI Agricultural Industry combining	Ag processing and support on farmland	The area plan recommends it for prime soils

On public water and sewer, C1, C2 and CH lots can be as small as 8,000 square feet. On a well and septic, they need 40,000 square feet.

Main Street, Highway 29 and Lampson Field

The area plan sets a clear hierarchy:

Main Street stays the business core. The plan names protecting Main Street as an economic development issue. It discourages strip commercial development outside the Kelseyville Community Development Area and new commercial elsewhere that would weaken downtown. Offices, restaurants and wholesale uses are considered appropriate in other commercial areas. Streetscape policies call for undergrounding Main Street utilities, curbs, gutters and sidewalks on both sides, street trees and sign-size limits.
Highway 29 for highway uses. Vehicle sales, factory outlets and restaurants are encouraged in commercial areas next to Highway 29. Industrial and service commercial uses near roads need screening and setbacks.
Lampson Field for aviation. Commercial uses around the airport should be limited to aircraft sales and service, flight training and commercial hangars. The plan describes a 3,443-foot runway serving general aviation and recreational flying. Commercial areas near the airport should connect to public sewer or a private community system.
Historic preservation. The plan supports designating historic sites, adopting historic preservation zoning and seeking Certified Local Government status. Ask whether any Main Street building is in a county HP combining district.

Farm, winery and home business uses

Big Valley’s farmland supports orchards and wine grapes, and the area plan says vineyards can use poorer soils under a Rural Lands designation. County Article 27 allows:

Produce stands up to 400 square feet, accessory to crops grown on the lot.
Farmers’ markets one day a week. A zoning permit is enough on commercial sites or agricultural sites with a permitted winery.
Cottage industries with a minor use permit: resident-run, up to two outside employees, inside a building of 1,200 square feet or less.
Home occupations, with employee limits that scale with acreage outside small residential lots.

Check winery and tasting room rules in the county’s agricultural district articles before you buy a vineyard parcel for hospitality.

Transfer tax, business tax and property tax

Kelseyville is unincorporated, so only the county documentary transfer tax of $1.10 per $1,000 applies, per the Assessor-Recorder fee schedule. Lodging pays the county’s 9% transient occupancy tax. The 2025 fire review shows no Kelseyville fire special tax. A sale generally triggers Proposition 13 reassessment. Ag land under a Williamson Act contract carries its own valuation rules. We did not verify a county business license tax.

Due diligence that matters in Kelseyville

Start with our commercial due diligence checklist, then add:

Confirm the district and whether the parcel is inside the Kelseyville community area or in rural Big Valley.
Get KCWD No. 3 water and sewer availability, or CSA 6 for Finley. Otherwise plan for well and septic lot sizes.
Near Lampson Field, check the Airport Land Use Compatibility Plan for use and height limits.
On Main Street, ask about historic status and frontage improvement requirements.
For ag-commercial uses, check Williamson Act contracts and the AI combining district.
Review fire flow, since the LAFCo review flagged water system limits.

Questions people ask

Who handles zoning in Kelseyville?

Lake County Community Development, under the county ordinance and the Kelseyville Area Plan.

Does the county allow new commercial outside Main Street?

The plan discourages strip and competing commercial outside the community area but supports highway uses near Highway 29.

What can go near Lampson Field?

The plan limits nearby commercial uses to aviation businesses such as aircraft sales and service, flight training and hangars.

Who provides sewer in Kelseyville?

Kelseyville County Waterworks District No. 3 serves the town. Outlying areas use septic or other districts.

Can I sell produce from my orchard?

Yes. A produce stand up to 400 square feet is allowed as an accessory to crops grown on the lot.

Is there a local transfer tax?

No city tax. Only the county’s $1.10 per $1,000 applies.

Does Diamond handle commercial property in Kelseyville?

Contact Matthew Martinez to discuss buying, selling or leasing commercial property in Kelseyville.

Sources & notes

Note: The area plan’s water and sewer counts date from its preparation around 1990, and its adoption date was not shown. Winery rules, C3 details and parcel zoning were not verified.

This page is general information, not legal or tax advice. Last reviewed October 2026 by Matthew Martinez.

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