Improper waste disposal and handling
When trash or recyclables are transported from residential trashcans and/or commercial dumpsters to landfills or recycling facilities, some items often fall off the vehicle or get blown away because they are lightweight. Often times people place trash and recyclables into overflowing bins, attracting unwanted birds or other wildlife scavengers, causing the excess debris to be carried or blow away and scattered onto the streets, beaches, waterways, etc.
Litter thrown on the streets is carried by wind and rainwater into storm drains. The polluted runoff flows into our streams and rivers, and eventually into the ocean. In California, storm drains are not connected to wastewater treatment plants, which means litter which enters the storm drains goes straight into the ocean. Litter on the beach or beach goers who neglect to properly dispose of their trash, is also a large source of trash that gets washed in the ocean by the wind.