sediments transportation hydrology
TRANSCRIPT
Why are sediment transport and deposition?
By: Laiba Sarwar
Why are sediment transport and deposition important?
Many ecosystems benefit from sediment transport and deposition.
Sediment builds aquatic habitats for spawning and benthic organisms .
It is also responsible for providing nutrients to aquatic plants, as well vegetation in near shore
ecosystems.
Sediment and aquatic life:
Sediment deposition creates habitats for aquatic life
While too much sediment can be
detrimental.
Too little sediment can also diminish
ecosystem quality.
Where Does Sediment Come From?
Sediment comes from geologic, geomorphic, and organic factors.
The amount, material and size of the
transported sediment.
Sum of these influences in any particular
waterway.
A body of water surrounded by swampland will be inundated with decomposing organic material.
Factors that influence sediment transport:
Water flow
Water flow also called water discharge, is the single most important element of sediment transport.
The flow of water is responsible for picking up, moving and depositing sediment in a waterway.
Water discharge can be simplified as area (a cross-section of the waterway) multiplied by velocity, or as a volume of water moved over time.
Weather Events
Precipitation causes water levels to initially rise, and then return to previous levels (base flow) over the course of hours or days.
Heavy rainfall over an area of loose soil and minimal vegetation will create runoff, carrying loose particles into the waterway.
Anthropogenic factors, such as dams and altered land use
Dams affect the water flow through complete detention or
restricted channels.
The restricted flow can cause the channel downstream of the
dam to become “sediment-starved”.
Human influence
Sediments in drinking water
Sediments as contaminants
Sediment is one of the most common drinking
water contaminants. Sediment normally occurs due to organic or inorganic
matter being carried by wind or runoff into open
water sources.
Type of sediments in water
• Organic sediments
• Inorganic sediment
Brown or orange colored sediment particles in water are usually rust
particles that stem from corroded
water pipes and plumbing
• Dissolved minerals, such as iron and manganese,
may also precipitate, leaving traces of
sediment• Black sediment can
indicate a high level of manganese in the water, or it could stem from a more local source, such as corroded steel piping
• White or tan sediment in drinking water is usually a result of calcium carbonate and magnesium carbonate, commonly known as pipe scale.
• This determine hardness and softness of water
Other metals in water
• Arsenic is a semi-metal
element • . It is odorless
and tasteless
It enters drinking water supplies from
natural deposits in the earth or
from agricultural and industrial
practices.
Arsenic
Asbestos
• Asbestos is a naturally occurring mineral
• from corroded asbestos-cement pipes
in the distribution system.
Uses of asbestos inproduction of cements,
floor tiles, paper products, paint,
This inorganic metal occurs naturally in the ground and
is often used in electrical equipment and electrical components. It generally
gets into water from run-off from mining operations,
discharge from processing plants and improper waste
disposal.
Beryllium