If pollution in the river is not cleaned up, it is left to settle at the bottom of the water and if something happens it might be stirred up and raise the bacteria levels again. There are many groups, like the San Diego River Park Foundation, that aim to clean up the river. Over the past four years, they have cleaned up almost one million pounds of trash from the river. However, there is still a lot of life being affected by the trash present at the river and in the ocean. "According to San Diego Coastkeeper, 80% of plastic litter in the oceans finds its way there through storm drains and urban runoff. Once there, the plastic is consumed by marine life or left to float. Approximately 100,000 marine animals are killed each year by plastics in the ocean in addition to one million birds." Said the 2008 Water Quality Report from the Surfrider Foundation.