Sediment+Notes

Sediments are non-living particles carried by the Great Water Cycle.

They can be (from smallest to largest)
 * silt
 * sand
 * gravel
 * dead decaying animals

When the water stops moving the sediments falls and kills the organisms underneath them

If the water is flowing faster it can carry bigger particles.

Water slowly erodes the land, but it keeps up our sandy beaches, salt marshes, and mud flats.

Forestry and agriculture destroy the protective plant cover and may allow heavy rains to wash the soil into the rivers.

The buildings and structures around the rivers make the earth bare and the soil gets carried into storm drains, rivers, and streams.

When you wash off your driveway and all the debris washes into the storm drain add a little bit of sediment into rivers.

Water flowing down rivers can carry away soil on the river banks.

Untreated sewage that is dumped into rivers or estuaries adds huge amounts of organic matter (produced by organisms) into the water.

Salmon farms can cause a lot of fish feces that stay in the cages or can be carried downstream with the current.

Dams or bridges can stop the flow of water and when the water stops the sediments drop to the river bottom instead of flowing into the sea.

Murky water doesn’t let the sunshine break through. Underwater plants can’t get enough sunlight to perform photosynthesis.

When it settles on the bottom it also prevents salmon from laying eggs on the gravel.

Sometimes the water gets to shallow for ships. The mud then has to be scooped from the bottom this process is called dredging. Dredging is a costly job.

The beaches are always losing sediments because of the current washing it away, but the sediment from the river comes and replaces it this is called the "dynamic balance". If there are dams the sediment from the rivers can't get to the beaches. The beaches start to disappear slowly along with all the organisms that live on them.