Sediment (A Hidden Problem)

Sediment

Sediment is the build up of sand, rock, and debris from natural occurrences and from residential and commercial construction sites.  Site development is probably one of the biggest concerns that we face with sediment build -up.  Different control measures are in place in various states to regulate sediment run-off.  Unfortunately it still occurs.

The natural geologic process for sediment comes down from the mountains and ends in the ocean.  The creation and process of sediment is long term. This is called the rock cycle.  This cycle began five billion years ago when the earth was young and still forming.


The rock cycle begins when volcanoes erupt and send lava and rocks spewing from the earth.  This forms mountain chains.  As the mountains erode from the elements, sediment begins to form.  This sediment begins its’ long journey back to the ocean. Making its’ way down the mountain through streams, into the rivers, and finally back into the ocean. As it settles it into the ocean, time and pressure form it into rock.  As the continental plates move, rock bedding is swallowed into the crust where continental plates meet (subduction zone).  This in turn pushes the bedding into the mantle and melts back into magma.  The process starts over again.  This doe not happen at the blink of an eye.  Millions and millions of years pass for this process to come full circle.  This is a description of the natural process which has occurred many time in the past however; due to site developments, humans have altered the process and causes problems with the natural flow.

Over time, the development of residential and commercial sites in every country has contributed to our streams and rivers to become altered and blocked by sediment.  Most sites have safety inspectors to make sure compliance is met on site, but occurrence still happens.  Areas of the sites that are not protected by control barriers allow run-off to settle into the water ways adjoining the site.  This in turn allows exceeding amounts [of sediment] into our water ways.  As this continues, build up of sediment begin to divert the natural flow and erodes the banks and causes more sediment to erode into the stream. As you read this, it doesn’t seem too big of a deal, but if this would continue, the build up can destroy properties and can possibly take homes.  For a good example, we can look at the Mississippi River.  This river has a long history of site development and high traffic. As this is a main artery in the United States, it is important to maintain the sediment build up.  Many state and federal organizations have implemented mechanical means to fight the build up of sediment into the river.  This is an ongoing process and takes many people and a lot of money to keep the sediment build-up at satisfactory levels.  So it all comes down to the sites being developed up stream to maintain and abide by the regulations put in place by our state and local governments.