Hydrology Flashcards
What is a Alluvial fan and what regions are they most common in
A fan shaped deposit of sediment lay down by a stream at the foot of a slope such as a mountain, canyon, or hill.
Common in dry regions
Define aquifer
Any sub surface material that holds a relatively large quantity of ground water and is able to transmit that water readily
Define backshore
The zone behind the shore between the beach berm in the back shore slope
Define backshore slope
The bank or bluff landward of the shore that is comprised of in-situ material
River condition prior to flooding
Bankfull discharge
The portion of streamflow contributed by ground water.
Baseflow
A ribbon of sand deposited crossed the mouth of a bay
Bay-mouth bar
What is a coastal Dune and how is it formed?
A sand dune that forms in coastal areas and is fed by sand from the beach
The central route of drainage, usually channel and valley in a drainage basin
Conveyance zone
A rain storm of a given intensity and frequency of reoccurrence used as the basis for sizing stormwater facilities such a storm sewers
Design storm
A strategy used in Stormwater management in which runoff is detained on site to be released later at some prescribed rate
Detention
Drainage basin
The area that contributes runoff to a stream river or lake
The number of kilometres of stream channels per square kilometre of land
Drainage density
Ephemeral stream
A stream without base flow i.e. one that flows only during and after rainstorms or snowmelt events
Eutrophication
Increase of biomass within a water body leading to infilling and the eventual disappearance of open water. Can be caused by an increase of nutrients in the water body
Evapotranspiration
The loss of water from the soil through in evaporation and transpiration
Floodway Fringe
The portion of the flood plain between the floodway and the outer limit of the flood risk area
Leachate
Water that is percolated through a solid and leached out some of the constituents. Problematic if emanating from decomposing waste or chemical landfill.
How does a Natural Levee form?
Buildup from sediment, silt, and other materials pushed aside by flowing water along side a stream or river for example
Littoral zone
Also known as nearshore, is the area of a sea lake or river that is close to the shore. Is the area where sunlight penetrates all the way to the sediment and allows aquatic plants (macrophytes) to grow
Littoral drift
Long shore transportation of sediments along the upper shore due to the action of breaking and longshore currents
Peak discharge
Flow which occurs when the maximum flood stage or depth is reached in a stream as a result of a storm event
Perennial stream
Characterized by consistent baseflow
Intermittent streams
Characterized by a base flow present in the channel at least once per year
What type of wetlands are typically characterized by herbaceous vegetation no taller than 6 feet
Marshes
What types of wetlands are typically characterized by having acidic soils
Bogs
Time of concentration definition
Amount of time it takes for water to flow from the most remote point in a watershed to the watershed outlet
Water circulates using five methods, what are those methods?
Precipitation, overland flow, infiltration, storage, and evapotranspiration
Groundwater flows using what action
Capillary action
Three general categories of wetlands, classified by soil and plant conditions
1) Areas with Hydrophytes and Hydric soils
2) areas without soils but with hydrophytes
3) areas without soils or hydrophytes that are periodically flooded
What types of wetlands would be classified as having both hydric soil and Hydrophytes
Marshes, bogs, swamps
What wetlands will be classified as having no soils but contain Hydrophytes
Seaweed covered rocky shores and aquatic beds
What wetlands have neither Hydrophytes nor hydric soils and experience periodic flooding
Gravel beaches and tidal flats
Five classifications of wetlands under the US federal fish and wildlife service?
Marine, Estuarine, Riverine, lacustrine, palustrine
Open oceans and the associated coast lines fall under what category of wetlands
Marine
Tidal waters of coastal rivers, and embayments, mangrove swamps and title flats Fall under what category of wetlands
Estuarine
Rivers and streams fall under what category of wetlands
Riverine
Lakes, Reservoir’s, and large ponds fall under what category of wetlands
Lacustrine
Marshes, wet meadows, fens, playas, pocosins, bogs, swamps, and small shallow ponds fall under what catagory of wetlands
Palustrine
What are two criticisms of constructed wetlands
Lacks the biodiversity of a naturally occurring system and may alter local hydrological regimes
A wetland fed by ground water, dominated by Pete Moss, rich and mineral salts and is alkaline is called…
A fen
Characteristics of a Lacustrine Wetland
Shallow depth, growth of aquatic vegetation, 20 acres or more, less than 30% vegetation cover
What are common characteristics of an estuarine wetland
Brackish waters, semi-enclosed where riverine water meets sea water, highly productive ecosystems, along shoreline, varies in size
Characteristics of a riverine wetland
Contain flowing water
Characteristics of palustrine wetlands
Non tidal, dominated by trees, shrubs, mosses or lichens
