Tiny flies emerging from bathroom drains are a surprisingly common issue in California homes. Many residents notice them hovering near sinks, showers, bathtubs, or toilet areas, often appearing suddenly and in increasing numbers. These insects are typically called drain flies, moth flies, or sewer gnats. While they are usually harmless, their persistent presence can signal hidden moisture, organic buildup, or plumbing conditions that allow them to breed.
California’s climate, water usage patterns, and home construction styles can create ideal environments for these insects. Understanding why they appear, how they survive in plumbing systems, and what their presence means helps homeowners address the issue effectively without unnecessary worry.
These flies are rarely random invaders. They usually indicate specific environmental conditions.
What Those Tiny Bathroom Flies Usually Are
Most tiny flies emerging from bathroom drains are commonly known as drain flies, sometimes called moth flies or sewer gnats. Scientifically, they belong to the family Psychodidae. These insects are small, fuzzy, and often appear moth-like because their wings are covered with fine hairs. They typically move slowly, resting on bathroom walls, tiles, or near sinks and showers, which makes them easier to notice than some other small flying insects…