Vflo
Encyclopedia
Vflo is a commercially available, physic
s-based distributed hydrologic model generated by Vieux & Associates, Inc. Vflo uses radar rainfall
data for hydrologic input to simulate distributed runoff
. Vflo employs GIS maps for parameterization via a desktop interface . The model is suited for distributed hydrologic forecasting in post-analysis and in continuous operations. Vflo output is in the form of hydrograph
s at selected drainage network
grids, as well as distributed runoff maps covering the watershed. Model applications include civil infrastructure
operations and maintenance, stormwater
prediction and emergency management
, continuous and short-term surface water runoff
, recharge estimation, soil moisture monitoring, land use
planning, water quality
monitoring, and water resources management.
s and precipitation controlling hydrologic processes, and thus improves upon lumped representations previously used in hydrologic modeling
. Historical practice has been to use lumped representations because of computational limitations or because sufficient data was not available to populate a distributed model database . Advances in computation
al speed; development of high-resolution precipitation data from radar
and satellites; and availability of worldwide digital data sets and GIS technology makes distributed, physics-based modeling possible . Vflo is designed to take advantage of the spatial variability of high resolution radar rainfall
input, GIS datasets, and hydraulic channel characteristics. Because it is physics
-based, it produces hydrograph
s based on conservation equations and the hydraulics of the drainage network
, and can be employed in locations where there are no rain gauge
s or previous modeling studies. In addition, Vflo’s network approach makes models scalable from upland watersheds
to river basins using the same drainage network
.
by loading precipitation maps for historical events and comparing simulated volume/peak hydrograph
s to observed hydrographs. Elevation data are taken from a digital elevation model
. A vector channel representation is employed. Parameterization utilizes digital data sets at any resolution, including LIDAR
terrain data and other digital maps of impervious area, soils, and land use/cover. Vflo is developed to utilize multi-sensor inputs from radar
, satellites, rain gauge
s, or model forecasts. The kinematic wave analogy is used to represent hydraulic conditions in a watershed
.
Physic
Physic may also refer to:*Physics, the study of matter, motion, and energy*Medicine, the science of healing*A type of Herb garden used for remedial purposes.*A professorship at either Cambridge or Dublin...
s-based distributed hydrologic model generated by Vieux & Associates, Inc. Vflo uses radar rainfall
Weather radar
Weather radar, also called weather surveillance radar and Doppler weather radar, is a type of radar used to locate precipitation, calculate its motion, estimate its type . Modern weather radars are mostly pulse-Doppler radars, capable of detecting the motion of rain droplets in addition to the...
data for hydrologic input to simulate distributed runoff
Runoff
Run-off or runoff may refer to:* Surface runoff, the flow of water, from rain, snow melt, or other sources, over land* Runoff model , a mathematical model describing the rainfall-runoff relations of a rainfall catchment area or watershed...
. Vflo employs GIS maps for parameterization via a desktop interface . The model is suited for distributed hydrologic forecasting in post-analysis and in continuous operations. Vflo output is in the form of hydrograph
Hydrograph
A hydrograph is a graph showing the rate of flow versus time past a specific point in a river, or other channel or conduit carrying flow...
s at selected drainage network
Drainage system (Geomorphology)
In geomorphology, a drainage system is the pattern formed by the streams, rivers, and lakes in a particular drainage basin. They are governed by the topography of the land, whether a particular region is dominated by hard or soft rocks, and the gradient of the land. Geomorphologists and...
grids, as well as distributed runoff maps covering the watershed. Model applications include civil infrastructure
Infrastructure
Infrastructure is basic physical and organizational structures needed for the operation of a society or enterprise, or the services and facilities necessary for an economy to function...
operations and maintenance, stormwater
Stormwater
Stormwater is water that originates during precipitation events. It may also be used to apply to water that originates with snowmelt that enters the stormwater system...
prediction and emergency management
Emergency management
Emergency management is the generic name of an interdisciplinary field dealing with the strategic organizational management processes used to protect critical assets of an organization from hazard risks that can cause events like disasters or catastrophes and to ensure the continuance of the...
, continuous and short-term surface water runoff
Runoff
Run-off or runoff may refer to:* Surface runoff, the flow of water, from rain, snow melt, or other sources, over land* Runoff model , a mathematical model describing the rainfall-runoff relations of a rainfall catchment area or watershed...
, recharge estimation, soil moisture monitoring, land use
Land use
Land use is the human use of land. Land use involves the management and modification of natural environment or wilderness into built environment such as fields, pastures, and settlements. It has also been defined as "the arrangements, activities and inputs people undertake in a certain land cover...
planning, water quality
Water quality
Water quality is the physical, chemical and biological characteristics of water. It is a measure of the condition of water relative to the requirements of one or more biotic species and or to any human need or purpose. It is most frequently used by reference to a set of standards against which...
monitoring, and water resources management.
History
Vflo considers the spatial character of the parameterParameter
Parameter from Ancient Greek παρά also “para” meaning “beside, subsidiary” and μέτρον also “metron” meaning “measure”, can be interpreted in mathematics, logic, linguistics, environmental science and other disciplines....
s and precipitation controlling hydrologic processes, and thus improves upon lumped representations previously used in hydrologic modeling
Hydrological modelling
Hydrologic models are simplified, conceptual representations of a part of the hydrologic cycle. They are primarily used for hydrologic prediction and for understanding hydrologic processes. Two major types of hydrologic models can be distinguished:...
. Historical practice has been to use lumped representations because of computational limitations or because sufficient data was not available to populate a distributed model database . Advances in computation
Computation
Computation is defined as any type of calculation. Also defined as use of computer technology in Information processing.Computation is a process following a well-defined model understood and expressed in an algorithm, protocol, network topology, etc...
al speed; development of high-resolution precipitation data from radar
Weather radar
Weather radar, also called weather surveillance radar and Doppler weather radar, is a type of radar used to locate precipitation, calculate its motion, estimate its type . Modern weather radars are mostly pulse-Doppler radars, capable of detecting the motion of rain droplets in addition to the...
and satellites; and availability of worldwide digital data sets and GIS technology makes distributed, physics-based modeling possible . Vflo is designed to take advantage of the spatial variability of high resolution radar rainfall
Weather radar
Weather radar, also called weather surveillance radar and Doppler weather radar, is a type of radar used to locate precipitation, calculate its motion, estimate its type . Modern weather radars are mostly pulse-Doppler radars, capable of detecting the motion of rain droplets in addition to the...
input, GIS datasets, and hydraulic channel characteristics. Because it is physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
-based, it produces hydrograph
Hydrograph
A hydrograph is a graph showing the rate of flow versus time past a specific point in a river, or other channel or conduit carrying flow...
s based on conservation equations and the hydraulics of the drainage network
Drainage system (Geomorphology)
In geomorphology, a drainage system is the pattern formed by the streams, rivers, and lakes in a particular drainage basin. They are governed by the topography of the land, whether a particular region is dominated by hard or soft rocks, and the gradient of the land. Geomorphologists and...
, and can be employed in locations where there are no rain gauge
Rain gauge
A rain gauge is a type of instrument used by meteorologists and hydrologists to gather and measure the amount of liquid precipitation over a set period of time....
s or previous modeling studies. In addition, Vflo’s network approach makes models scalable from upland watersheds
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...
to river basins using the same drainage network
Drainage system (Geomorphology)
In geomorphology, a drainage system is the pattern formed by the streams, rivers, and lakes in a particular drainage basin. They are governed by the topography of the land, whether a particular region is dominated by hard or soft rocks, and the gradient of the land. Geomorphologists and...
.
Formulation
Vflo is suited for distributed hydrologic forecasting in post-analysis and continuous operations. Vflo models may be calibratedCalibration
Calibration is a comparison between measurements – one of known magnitude or correctness made or set with one device and another measurement made in as similar a way as possible with a second device....
by loading precipitation maps for historical events and comparing simulated volume/peak hydrograph
Hydrograph
A hydrograph is a graph showing the rate of flow versus time past a specific point in a river, or other channel or conduit carrying flow...
s to observed hydrographs. Elevation data are taken from a digital elevation model
Digital elevation model
A digital elevation model is a digital model or 3-D representation of a terrain's surface — commonly for a planet , moon, or asteroid — created from terrain elevation data....
. A vector channel representation is employed. Parameterization utilizes digital data sets at any resolution, including LIDAR
LIDAR
LIDAR is an optical remote sensing technology that can measure the distance to, or other properties of a target by illuminating the target with light, often using pulses from a laser...
terrain data and other digital maps of impervious area, soils, and land use/cover. Vflo is developed to utilize multi-sensor inputs from radar
Weather radar
Weather radar, also called weather surveillance radar and Doppler weather radar, is a type of radar used to locate precipitation, calculate its motion, estimate its type . Modern weather radars are mostly pulse-Doppler radars, capable of detecting the motion of rain droplets in addition to the...
, satellites, rain gauge
Rain gauge
A rain gauge is a type of instrument used by meteorologists and hydrologists to gather and measure the amount of liquid precipitation over a set period of time....
s, or model forecasts. The kinematic wave analogy is used to represent hydraulic conditions in a watershed
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...
.
Specific simulation options
- Rainfall input
- Radar-rainfallWeather radarWeather radar, also called weather surveillance radar and Doppler weather radar, is a type of radar used to locate precipitation, calculate its motion, estimate its type . Modern weather radars are mostly pulse-Doppler radars, capable of detecting the motion of rain droplets in addition to the...
: UF, ASCIIESRI gridAn Esri grid is a raster GIS file format developed by Esri, which has two formats:#A proprietary binary format, also known as an ARC/INFO GRID, ARC GRID and many other variations...
, NEXRADNEXRADNEXRAD or Nexrad is a network of 159 high-resolution Doppler weather radars operated by the National Weather Service, an agency of the National Oceanic and Atmospheric Administration within the United States Department of Commerce...
Level II, CSVComma-separated valuesA comma-separated values file stores tabular data in plain-text form. As a result, such a file is easily human-readable .... - Satellite data
- Rain gaugeRain gaugeA rain gauge is a type of instrument used by meteorologists and hydrologists to gather and measure the amount of liquid precipitation over a set period of time....
s, Barnes objective analysisBarnes interpolationBarnes interpolation, named after Stanley L. Barnes, is the interpolation of unstructured data points from a set of measurements of an unknown function in two dimensions into an analytic function of two variables... - Quantitative precipitation estimates from model forecasts
- Multi-sensor precipitation estimates
- Radar-rainfall
- EvapotranspirationEvapotranspirationEvapotranspiration is a term used to describe the sum of evaporation and plant transpiration from the Earth's land surface to atmosphere. Evaporation accounts for the movement of water to the air from sources such as the soil, canopy interception, and waterbodies...
- SnowmeltSnowmeltIn hydrology, snowmelt is surface runoff produced from melting snow. It can also be used to describe the period or season during which such runoff is produced. Water produced by snowmelt is an important part of the annual water cycle in many parts of the world, in some cases contributing high...
- Sensitivity analysisSensitivity analysisSensitivity analysis is the study of how the variation in the output of a statistical model can be attributed to different variations in the inputs of the model. Put another way, it is a technique for systematically changing variables in a model to determine the effects of such changes.In any...
- Inundation mapping
- InfiltrationInfiltration (hydrology)Infiltration is the process by which water on the ground surface enters the soil. Infiltration rate in soil science is a measure of the rate at which soil is able to absorb rainfall or irrigation. It is measured in inches per hour or millimeters per hour. The rate decreases as the soil becomes...
- Enhanced Green-Ampt infiltration module with initial saturation calibration factor (slider), saturated hydraulic conductivity, wetting front suction, effective porosity, and soil depth
- Abstraction and impervious area parameters with ASCIIESRI gridAn Esri grid is a raster GIS file format developed by Esri, which has two formats:#A proprietary binary format, also known as an ARC/INFO GRID, ARC GRID and many other variations...
import/export
- Overland flow
- Manning's equation
- Channel flow
- Kinematic Wave Analogy
- Modified Puls
- Observed flow
- Looped rating curve modification (Jones method)
- Rating curves and cross sections for complex hydraulics
- Flood watch points
- Design storms, SCS, user generated
Applications
- Continuous and short-term surface water runoffSurface runoffSurface runoff is the water flow that occurs when soil is infiltrated to full capacity and excess water from rain, meltwater, or other sources flows over the land. This is a major component of the water cycle. Runoff that occurs on surfaces before reaching a channel is also called a nonpoint source...
- Stormwater prediction and management
- Flash floodFlash floodA flash flood is a rapid flooding of geomorphic low-lying areas—washes, rivers, dry lakes and basins. It may be caused by heavy rain associated with a storm, hurricane, or tropical storm or meltwater from ice or snow flowing over ice sheets or snowfields...
forecasting - Operational flood alert
- Flood event reconstruction
- Design Storm development
- Recharge estimation
- Soil moisture monitoring
- HydrologyHydrologyHydrology is the study of the movement, distribution, and quality of water on Earth and other planets, including the hydrologic cycle, water resources and environmental watershed sustainability...
and HydraulicsHydraulicsHydraulics is a topic in applied science and engineering dealing with the mechanical properties of liquids. Fluid mechanics provides the theoretical foundation for hydraulics, which focuses on the engineering uses of fluid properties. In fluid power, hydraulics is used for the generation, control,...
studies - Land useLand useLand use is the human use of land. Land use involves the management and modification of natural environment or wilderness into built environment such as fields, pastures, and settlements. It has also been defined as "the arrangements, activities and inputs people undertake in a certain land cover...
planning scenarios - Water qualityWater qualityWater quality is the physical, chemical and biological characteristics of water. It is a measure of the condition of water relative to the requirements of one or more biotic species and or to any human need or purpose. It is most frequently used by reference to a set of standards against which...
studies - HydropowerHydropowerHydropower, hydraulic power, hydrokinetic power or water power is power that is derived from the force or energy of falling water, which may be harnessed for useful purposes. Since ancient times, hydropower has been used for irrigation and the operation of various mechanical devices, such as...
management - HydrologyHydrologyHydrology is the study of the movement, distribution, and quality of water on Earth and other planets, including the hydrologic cycle, water resources and environmental watershed sustainability...
education - Hydrologic research