Hydrology Concepts Quiz

Hydrology

• Hydrology is the study of water in the environment, including its distribution, movement, and properties.

Hydraulic Conductivity

• A measure of the ease with which water can move through pore spaces or fractures in soil or rock.

Watershed

• The land area that drains rainfall and snowmelt into a common outlet like a river or reservoir.

Streamflow

• The flow of water in a natural or artificial channel, such as a river, stream, or creek.

Infiltration

• The process by which water on the ground surface enters the soil.

Runoff

• Water that flows over the surface of the ground, typically after rainfall, that does not infiltrate into the soil.

Evapotranspiration

• The combined process of water evaporation from the soil and surface, and transpiration from plants.

Precipitation

• Any form of water, liquid or solid, that falls from the atmosphere, including rain, snow, sleet, and hail.

Baseflow

• The portion of streamflow that comes from groundwater seeping into the stream, as opposed to direct runoff from rainfall.

Floodplain

• The flat or nearly flat land next to a stream or river, which is subject to periodic flooding.

Catchment Area

• Another term for watershed, referring to the area that contributes water to a specific stream, river, or reservoir.

Permeability

• The ability of a material, typically soil or rock, to transmit water through its pores or fractures.

Hydrograph

• A graph showing the flow rate (discharge) of a stream or river as a function of time.

Peak Discharge

• The maximum flow rate of water during a specific event, such as a storm.

Saturation Zone

• The part of the ground where all pores are filled with water, typically referring to groundwater.

Unsaturated Zone

• The area above the water table where the soil is not fully saturated with water, containing both air and water in the pores.

Water Table

• The upper surface of the saturated zone, where the soil is completely filled with water.

Aquifer

• A body of permeable rock or sediment that can store and transmit groundwater.

Consolidated Rock

• Hard, dense rock formations, such as granite or basalt, which are typically less permeable than unconsolidated materials.

Unconsolidated Material

• Loose material like sand, gravel, or clay that is more permeable and can store significant amounts of water.

Infiltration Rate

• The rate at which water enters the soil, typically measured in millimeters per hour (mm/h).

Hydraulic Head

• The height of the water surface in a well, which represents the potential energy of the groundwater at that point.

Transmissivity

• The ability of an aquifer to transmit water, typically measured in square meters per day (m²/day).

Stormwater

• Water that originates from precipitation events and flows over land surfaces.

Retention Basin

• A structure designed to store stormwater and release it gradually to prevent flooding.

Detention Basin

• A storage facility designed to temporarily hold water during a storm event to control runoff.

Flood Frequency

• The statistical probability that a flood of a particular size will occur in a given time period.

Floodplain Zoning

• Regulations that govern land use in flood-prone areas to reduce the risk and impact of floods.

Seepage

• The slow movement of water through the soil or rock, often into or out of groundwater bodies.

Hydraulic Radius

• The ratio of the cross-sectional area of flow in a stream or river to its wetted perimeter.

Manning's Equation

• A formula used to estimate the flow of water in an open channel, based on channel characteristics and flow conditions.

Watershed Management

• The planning and management of land and water resources within a watershed to achieve sustainable water use and environmental protection.

Stormwater Runoff Coefficient

• A dimensionless value that represents the fraction of total precipitation that becomes runoff.

Water Quality Index

• A numerical scale used to measure the quality of water based on various chemical and physical parameters.

Evaporation

• The process by which water changes from liquid to vapor, usually from the surface of water bodies or soil.

Transpiration

• The process by which water is absorbed by plant roots and released as vapor through plant leaves.

Stream Order

• A classification system for streams based on their position in the watershed hierarchy, from headwaters to larger rivers.

Channelization

• The process of altering the natural course of a stream or river, often for flood control or navigation.

Flood Control Dam

• A structure built to control the flow of a river and mitigate the impact of flooding.

Water Budget

• A method for tracking the input, storage, and output of water within a defined area, helping to understand water availability.

Surface Water

• Water that is found in rivers, lakes, streams, and reservoirs, as opposed to groundwater.

Groundwater Recharge

• The process by which water from precipitation or surface water infiltrates into the ground to replenish aquifers.

Isotopic Tracing

• A method using isotopes to study the movement and sources of water in the hydrological cycle.

Hydrologic Cycle

• The continuous movement of water through the atmosphere, surface, and subsurface, including processes like evaporation, condensation, and precipitation.

Impervious Surface

• A surface that does not allow water to pass through it, such as concrete or asphalt, contributing to increased runoff.

Siltation

• The accumulation of fine particles, like silt or clay, in water bodies due to erosion or runoff.

Water Quality Modeling

• The use of mathematical models to predict the behavior of water quality in a system under various conditions.

Critical Flow

• The flow of water in an open channel where the velocity of flow is equal to the wave velocity, often associated with the minimum energy state.

Sediment Transport

• The movement of sediment by water, wind, or ice, including erosion, deposition, and transport within rivers and streams.

Flow Duration Curve

• A graph that shows the percentage of time a specific flow rate is equaled or exceeded over a given period.

Hydrograph

• A graph showing the variation of streamflow or discharge over time in response to a rainfall or other hydrological event.

Peak Discharge

• The highest flow rate recorded during a specific event or period, often occurring shortly after a storm.

Baseflow

• The normal, steady flow of water in a stream or river, primarily coming from groundwater, typically represented by the lower, more stable portion of the hydrograph.

Rising Limb

• The portion of the hydrograph that shows the increase in streamflow as runoff begins to enter the river or stream.

Falling Limb

• The portion of the hydrograph after the peak, showing the decrease in discharge as runoff subsides and the system returns to baseflow conditions.

Lag Time

• The time between the peak of precipitation and the peak discharge on the hydrograph, indicating how long it takes for runoff to reach the river.

Time to Peak

• The time from the beginning of a rainfall event to the point when the hydrograph reaches its peak discharge.

Stormflow

• The portion of flow in a river or stream that results from direct runoff during a storm, typically characterized by rapid increases in flow.

Unit Hydrograph

• A theoretical hydrograph showing the runoff resulting from a unit depth of rainfall over a specific duration in a watershed.

Direct Runoff

• The portion of rainfall that directly contributes to runoff, excluding infiltration losses or baseflow.

Recession Limb

• The part of the hydrograph after the peak where the discharge gradually decreases as runoff slows and the river returns to normal levels.

Hydrograph Shape

• The overall pattern or form of a hydrograph, which reflects the characteristics of the watershed, storm event, and runoff behavior.

Cumulative Hydrograph

• A hydrograph where the flow is plotted as cumulative discharge over time, showing the total volume of water discharged during an event.

Flash Flood Hydrograph

• A type of hydrograph with a sharp, rapid increase in discharge, often seen in flash floods, where the rising limb is steep and the peak is quickly reached.

Flood Hydrograph

• A hydrograph specifically related to a flood event, showing the rapid increase in discharge and the prolonged recession of flow.

Baseflow Separation

• A method for separating the baseflow component from the total streamflow in a hydrograph to better understand the contributions of direct runoff versus groundwater.

Hydrological Response

• The way in which a watershed reacts to a rainfall or storm event, which can influence the timing and magnitude of the hydrograph.

Excess Rainfall

• The amount of rainfall that contributes to runoff, calculated by subtracting infiltration and losses from the total rainfall.

Recession Curve

• A curve that represents the gradual decrease in streamflow after the peak discharge, typically reflecting how long it takes for the watershed to return to baseflow conditions.

Flow Duration Curve (FDC)

• A plot derived from a hydrograph that shows the percentage of time a specific discharge is equaled or exceeded during a given period, helping to characterize flow variability.

Water Code of the Philippines

• Governs the utilization, conservation, and management of water resources in the Philippines.

Sanitary Code of the Philippines

• Establishes sanitary regulations to ensure public health through hygiene, waste disposal, and food safety.

Test your knowledge of key hydrology concepts with this quiz! Questions cover topics such as hydraulic head, stormwater runoff, groundwater recharge, and more. Perfect for students and enthusiasts looking to deepen their understanding of hydrology.