Urban Water Management - Autumn 2026 Quiz 1 Review Flashcards

Vocabulary review flashcards generated from the Autumn 2026 Urban Water Management Quiz 1 review sheet by P.F. Hudson.

Aquiclude

An impermeable body of rock or sediment that acts as a barrier to groundwater flow.

Aquifer

An underground layer of permeable rock, sediment, or soil that holds and transmits groundwater.

Artesian aquifer

A confined aquifer containing groundwater under positive pressure, bounded above and below by aquicludes or aquitards.

Artesian well

A well drilled into an artesian aquifer where subterranean pressure causes water to rise naturally without pumping.

Baseflow

The portion of streamflow sustained between precipitation events, primarily supplied by groundwater discharge into the channel.

Capillary flow

The movement of water through narrow soil pore spaces against gravity due to surface tension and adhesive forces.

Clastic sediment

Accumulations of solid rock and mineral fragments produced by the physical weathering and erosion of pre-existing rocks.

Confined aquifer

An aquifer trapped beneath an impermeable layer (aquiclude), placing its groundwater under pressure higher than atmospheric pressure.

Discharge (streamflow)

The volume rate of water flow passing through a river or stream cross-section per unit of time.

Drought

A prolonged period of deficiency in precipitation leading to a significant water shortage in hydrologic or soil systems.

Evaporation

The physical process by which liquid water is converted into water vapor and transferred to the atmosphere.

Evapotranspiration (ET)

The total amount of water transferred from the Earth's surface to the atmosphere via surface evaporation and plant transpiration.

Grey and green infrastructure

Built, conventional engineering structures (grey) contrasted with natural, vegetated, or engineered ecosystems (green) used for urban stormwater and water management.

Groundwater

Water residing beneath the Earth's surface within soil pore spaces and rock fractures.

Hydraulic infrastructure

Civil engineering structures designed to control, direct, store, divert, or treat water resources.

Hydrograph

A graph illustrating streamflow discharge over time past a specific point, featuring components such as lag time, peak/crest, rising limb, and falling limb.

Flashy vs. smooth hydrograph

A flashy hydrograph exhibits a rapid rising limb and a sharp peak discharge (typical of urban catchment systems), whereas a smooth hydrograph shows a gradual rise and lower peak over a longer time (typical of natural catchments).

Impervious cover

Artificial surface materials such as pavement, concrete, and rooftops that prevent the infiltration of water into the ground.

Infiltration

The downward entry and movement of surface water into the soil matrix.

Infiltration curve: natural vs. urban

A plot of infiltration rate over time; natural curves sustain higher infiltration rates, whereas urban curves drop rapidly due to high impervious surface cover.

Interbasin water transfers

The engineered diversion of water from one drainage basin to another to alleviate regional water scarcity, raising ecological and management concerns.

Nature-based-solutions (NbS)

Actions defined by the UN to protect, sustainably manage, and restore natural or modified ecosystems to address environmental and societal challenges effectively.

Percolation

The downward movement of water through soil profile layers and subsurface geologic strata toward the groundwater table.

Permeability

The property or capacity of soil or rock to transmit fluid through interconnected pore spaces.

Phreatic zone

The subterranean zone below the water table where all soil pores and rock fractures are completely saturated with water.

Piezometric (potentiometric) surface

An imaginary plane representing the hydrostatic pressure head of groundwater in a confined aquifer, equal to the elevation water would reach in a well.

Porosity

The measure of void spaces in soil or rock, expressed as a fraction or percentage of total volume.

Recharge zone

A geographical area where surface water infiltrates downwards to replenish an underlying aquifer.

Rhine streamflow and severity of 2026 drought

The specific streamflow reduction metrics and severe hydrological impacts evaluated on the Rhine River during the 2026 drought.

Runoff

Precipitation or snowmelt that flows overland across the ground surface instead of infiltrating into the soil.

Soil moisture

Water stored in the unsaturated soil pore space above the phreatic zone.

Stoma

A microscopic opening on the outer surface of plant leaves and stems that allows gas exchange and releases water vapor during transpiration.

Subsidence

The gradual settling or sudden sinking of the land surface caused by subsurface compaction, often triggered by excessive groundwater extraction.

The Hague water supply, dunes and Afgedamde Maas River project

An integrated Dutch urban water management system utilizing dune filtration and water from the Afgedamde Maas River to provide clean public drinking water.

Transpiration

The physiological process by which plants absorb water through roots, transport it, and release it as water vapor through leaf stomata into the atmosphere.

Unconfined aquifer

An aquifer whose upper boundary is the water table, open to direct atmospheric pressure through permeable overlying materials.

Urban heat island effect

The phenomenon where urban areas experience significantly elevated temperatures compared to surrounding rural areas due to human activity, dense infrastructure, and reduced vegetation.

Urban sponge

An urban planning concept and set of nature-based measures designed to absorb, store, filter, and release rainwater within cities to reduce flooding and increase climate resilience.

Vadose zone

The unsaturated subsurface zone situated between the ground surface and the water table.

Water stress

A condition occurring when human and ecological demand for clean water exceeds the available volume during a given period.

Water table

The upper boundary surface of the phreatic zone where fluid pore pressure equals atmospheric pressure.

Watershed

An area of land (catchment or drainage basin) that drains all surface runoff to a common outlet, delineated by drainage divides and interfluves, and fed by headwater tributaries, tributaries, and distributaries.