Lake guide
Clear Lake
Lakeport, Lake County, CA
Overview
Clear Lake is the largest natural freshwater lake entirely within California, covering about 68 square miles in Lake County. It runs about 19 miles long and 8 miles wide, with roughly 100 miles of shoreline, and sediment cores show it is at least 480,000 years old. Mount Konocti rises from the middle of the south shore. Lakeport, Clearlake, Kelseyville, Lucerne, Upper Lake and Lower Lake all sit on or near the water.
Layout and who boats here
The lake splits into three parts: the large Upper Arm, the Oaks Arm and the Lower Arm. It is shallow for its size, averaging about 27 feet deep with a maximum near 60 feet, at about 1,329 feet elevation. Bass anglers are the core crowd, and tournaments run much of the year, but ski boats, pontoons, wakeboard boats and sailboats share the water. Public ramps are spread around the shore, including Clear Lake State Park near Kelseyville and Redbud Park in the city of Clearlake, plus many resort launches.
What makes it different
Lake County runs its own invasive mussel program on top of state rules. Every boat and its trailer needs a Lake County mussel sticker before launching, and visitor stickers expire at the end of each calendar month. Boats returning from out-of-county water must be re-screened. The lake is naturally nutrient-rich and sees cyanobacteria (harmful algal) blooms, mostly from spring through fall, so check current water-quality data before swimming or letting dogs in the water.
Getting there & access
Before you launch: Lake County screening
Every boat and its trailer must carry a Lake County mussel sticker before launching. Visitors get screened before their first launch in every calendar month. You fill out a Mussel Screening Application, answer screening questions, show DMV registration and pay a $20 fee. Stickers are sold at screening locations around the lake; the County posts the current list and map online and at public ramps. Some locations open early or late, so call ahead.
Coming back from another lake
A boat that has launched in an out-of-county lake or river must be re-screened when it returns to Lake County. The County doesn't charge for these re-screenings. Boats that aren't clean, drained and dry, or that look like a risk, get a physical inspection by an Authorized Inspector.
Public ramps
Clear Lake State Park, 5300 Soda Bay Road in Kelseyville, has a ramp with two boarding floats and about 106 car-and-trailer spaces. Redbud Park on Ballpark Avenue in the City of Clearlake also has a public launch on the Lower Arm. Many resorts around the shore also launch boats.
Getting around the lake
The Upper Arm is the big open water off Lakeport and Lucerne. The narrower Oaks and Lower Arms run southeast past Mount Konocti toward Clearlake and Lower Lake. The lake is shallow, so afternoon wind builds a short, steep chop quickly on the Upper Arm.
Amenities
- State Park ramp — Clear Lake State Park, Kelseyville: two boarding floats, about 106 trailer spaces, transient tie-ups
- City ramp — Redbud Park launch, Ballpark Avenue, City of Clearlake
- Mussel screening locations — Network of screeners around the lake; mobile screeners available on request
- Camping — Campsites, showers and a swim area at Clear Lake State Park
- Fish cleaning — Fish cleaning station at the State Park ramp
- Resort launches and marinas — Many lakeside resorts with docks and launches in Clearlake, Lakeport and Kelseyville
Rules & official resources
- Every visitor boat and its trailer must have Lake County Visitor Mussel Stickers before launching; visitor stickers expire at the end of each calendar month and screening is required before the first launch in every calendar month
- Resident boats and trailers need Resident Mussel Stickers before launching; they expire at the end of each calendar year. The screening fee is $20
- Boats must be re-screened when returning to Lake County after launching in an out-of-county body of water; there is no charge for this re-screening
- Boats that aren't clean, drained and dry, or appear to pose a risk, must pass a physical inspection; if suspected larvae are found the boat can't launch until decontaminated and re-inspected, and boats with adult mussels are quarantined by the state
- Motorized vessels used in fresh water must display the California Mussel Fee sticker, one on each side of the hull next to the registration sticker; paying the fee doesn't exempt a boat from local inspections or inspection fees
- California Boater Card required for all operators of motorized vessels, regardless of age, since January 1, 2025
Common boat service needs here
Hull cleaning after algae season
Clear Lake's nutrient-rich water leaves a green-brown scum line and staining on hulls kept in the water through summer and fall. Owners with boats in resort slips often book hull cleaning or a haul-and-scrub at season's end.
Find Bottom Cleaning, Hull Cleaning & Dive Services providers →Engine service for tournament boats
Bass boats here run hard, often in tournaments most of the year. Lower-unit service, impeller changes and pre-season tune-ups are steady local demand.
Find Marine Mechanics & Engine Service providers →Washdowns and detailing
Algae, hard-water spotting and bird droppings build up fast, and boats trailered between lakes also need to be clean and dry to pass screening. Regular wash-and-wax service helps both.
Find Boat Detailing & Washing providers →Covers and upholstery
Hot, dry Lake County summers bake vinyl seats, carpet and canvas. Fitted covers and seat repairs are common needs.
Find Canvas, Covers & Upholstery providers →Guides & FAQs
Nearby providers
No providers listed near this location yet — check back soon.
Sources
Last verified October 6, 2026