Excessive watering of eyes can be caused by:
1. Dry eye syndrome. Dry eyes are not only caused by poor quantity of tears, but also by the low quality. When there is a lack of a certain substance in your tears, low quality will be compensated by quantity.
2. Conjunctivitis or pink eye. When you suffer from conjunctivitis which is caused by bacterial, viral, and fugal infections, more tears will be produced to rinse and soothe the irritation.
3. Allergies. Excessive tears can result from allergies to certain items. Or some people just have allergic eyes.
4. Tear duct blockage. When the normal passage of tears, tear duct, is blocked, the tears can only flow out.
5. Photophobia. If your eyes have been exposed to bright light, they may water a lot.