When a river or stream enters a body of water, what happens to the sediments and what does it build? The sediments drop down to the bottom and build rocks. The sediments drop down to the bottom and build rocks. The sediments drop down to the bottom and begin building new land. The sediments drop down to the bottom and begin building new land. The sediments continue to the ocean and remain in the water. The sediments continue to the ocean and remain in the water. The sediments continue in the water and build floating islands. The sediments continue in the water and build floating islands.