Quagga mussels are a problem at lakes across California, including Lake Piru Reservoir. The invasive species are extremely destructive, clogging pipes used for drinking water, irrigation and hydropower, and necessitating extensive containment efforts. They also block boat motors and harm native fish by altering the habitat and the food web. After quagga mussels were discovered in Lake Piru in 2013, United Water Conservation District (UWCD) developed a Monitoring and Control Plan to contain the infestation. As part of that plan, a strict inspection policy is in effect for all watercraft entering and leaving Lake Piru.
Personnel from United Water Conservation District, which owns the lake, inspect all boats entering and exiting Lake Piru to limit the spread of quagga mussels. Failure to undergo an inspection prior to launch may result in a citation. Boaters should download and print the Lake Piru Vessel Inspection Permit Application.