Watering eyes typically occur when the eyes produce excessive tears or the tears cannot drain away properly, according to the National Health Service. Blocked tear ducts cause eyes to water, and they usually result from age, inflammation, trauma or compression. Excessive tear production results from eye irritation caused by problems such as infection, allergy, chemical irritant, injury, entropion and ectropion.
Healthline explains that tears keep the eyes lubricated, and they wash away dust and foreign objects. When too much tearing occurs, the excess tears overwhelm the tear ducts, causing watery eyes. When a person’s tears do not have the right balance of water, salt and oils, it is also possible for the eyes to become overly dry, causing irritation and overproduction of tears. Healthline states that laughing, yawning and being emotional cause a temporary production of excess tears. Other common causes include eye strain, environmental factors like bright light, weather conditions like wind, allergies, cold, sinus problems, eyelid inflammation, an eyelid turned inward, an eyelid turned outward, a cut or scrape on the eye, an ingrown eyelash, medications and cancer treatments.
MedicineNet says that excessive tearing is possibly a sign of an underlying condition or disease. Tears are produced in the tear, or lacrimal, gland and drain through the tear ducts. They well up in the eyes and fall excessively when tear ducts become blocked, leading to epiphora or watery eye.