Small Aircraft; High Wing; 1 Eng; Fixed Gear
Flight Crew Commercial; Flight Crew Instrument
Flight Crew Total 860
ATC Issue All Types; Airspace Violation All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Flight Crew Took Evasive Action
Environment - Non Weather Related
I was in a small fixed wing aircraft at 3;500 feet traversing to Vacaville via over Lake Berryessa. As we were at cruise; [we] spotted a boat on the lake that had a line going up towards the sky. We then both observed a paraglider; connected to that boat at approximately 3;000 feet and around a mile to our 11 o'clock position. I then maneuvered to the right to gain distance from the paraglider. We then observed the paraglider continued to be towed up to at least 3;500 feet; where he was then released. As the paraglider descended; they were doing multiple aerobatics. I made numerous calls on the multi-lake frequency 122.9; but had no response from the boat or ground crews. There were also no NOTAMs listed for this activity nor is there anything denoted on sectional charts. Lake Berryessa is a highly traveled air route for numerous VFR and IFR traffic. These paragliders present a serious risk; being towed over 3;000 feet with a tow line that is impossible for a pilot to see. A weekend flyer; traversing this area; would never expect to see this kind of paragliding activity.
During routine flight over Lake Barryessa; a pilot reported observing a paraglider in excess of 3;000 feet while under tow from watercraft causing pilot to take evasive action.