Shifting+Sediments


 * Shifting Sediments**

__**What is Sediment?**__ Sediments are non-living particles that are carried by the flow of the water to different places. Sediment can be: gravel, silt, rock, sand, dead leaves, and dead organisms. Precipitation erodes the land which maintains beaches, mud flats, and salt marshes.The way erosion works is that as the water flows along the land, it picks up sediment and drags it away. After time there is less dirt where the water was running. On the edge of a river bank, this can cause the river bank to fall into the river. When ever the currents pulls sand away from beaches, the current comes back in and deposits more sand which is a continuing cycle. This is called dynamic balance.

__**What are the environmental problems with sediment?**__ There is a problem with sediment. There can be too much sediment. Construction and runoff are two major ways that sediments are carried into the waterways. When all of the sediment gets into the water it becomes foggy and clogged up. This prevents the regular amount of sunlight from entering the water which makes it so plants and some organisms can’t live there. This is a growing environmental problem. Construction sites can deposit more sediment into a waterway than would normally be deposited in many decades. The houses that are near the water are the ones that deposit the most sediment into the water. Construction sites further inland are less of a threat unless there is some way for the sediment to find its way into the water. When there are dams in the waterways the current carries the sediment to the dam, but when the current reaches the dam the water can’t flow any further and the sediment is dropped. When this happens the sediment builds up, but can’t reach the beaches to replace lost sand. This means that the sand will not be able to get to the beaches so the beaches just keep losing more and more sand until they are gone. This will slowly cause the beaches and marshes to disappear, along with the organisms that live there.

__**What should Basgo do?**__ To keep this environmental problem from growing, the town of Basgo should consider building the housing developments further inland to prevent runoff from reaching the esuary. If the town would like to have the houses on the edge of the water they should make some kind of barrier to keep sediment from flowing into the river. Some barriers could be trees or fences.