In hydrology, a water balance equation can be used to describe the flow of water in and out of a system. A system can be one of several hydrological domains, such as a column of soil or a drainage basin. Water balance can also refer to the ways in which an organism maintains water in dry or hot conditions. It is often discussed in reference to plants or arthropods, which have a variety of water retention mechanisms, including a lipid waxy coating that has limited permeability.
Funded by government, and implemented in 2003, the Water Balance Model Online is a scenario. The tool fills a gap not covered by commercial software. Material Balance Calculations Using the Excel Spreadsheet Introduction Material balance is a fundamental petroleum reservoir engineering tool that can be used to provide an understanding of a reservoir and the influence of any connecting aquifer. The basic requirements for the application of material balance to a reservoir include.
A general water balance equation is:
- is precipitation
- is evapotranspiration
- is streamflow
- is the change in storage (in soil or the bedrock / ground water)
This equation uses the principles of conservation of mass in a closed system, whereby any water entering a system (via precipitation), must be transferred into either evaporation, surface runoff (eventually reaching the channel and leaving in the form of river discharge), or stored in the ground. This equation requires the system to be closed, and where it isn't (for example when surface runoff contributes to a different basin), this must be taken into account.
Extensive water balances are discussed in agricultural hydrology.
A water balance can be used to help manage water supply and predict where there may be water shortages. It is also used in irrigation, runoff assessment (e.g. through the RainOff model ), flood control and pollution control. Further it is used in the design of subsurface drainage systems which may be horizontal (i.e. using pipes, tile drains or ditches) or vertical (drainage by wells). To estimate the drainage requirement, the use of a hydrogeological water balance and a groundwater model (e.g. SahysMod) may be instrumental.
The water balance can be illustrated using a water balance graph which plots levels of precipitation and evapotranspiration often on a monthly scale.
Several monthly water balance models had been developed for several conditions and purposes. Monthly water balance models had been studied since the 1940s.
Several diagnostic measures in hydrology can be used to select and evaluate the performance of water balance models. Princess mononoke symphonic suite rare.
- Evaluate the components of the hydrologic cycle
- Climate change impact assessment
- Flow forecasting and project design
- Models using precipitation (rainfall) as input
- Models using rainfall and temperature as input
- Models using rainfall and potential evaporation as input
- Models using daily input data
- ^'RainOff, surface runoff model'. Retrieved 2010-07-28.
- ^'Free articles and software on drainage of waterlogged land under irrigation'. Retrieved 2010-07-28.
- ^'Sahysmod groundwater model'. Retrieved 2010-07-28.
- ^Xu, C.-Y.; V.P. Singh (1998). 'A Review on Monthly Water Balance Models for Water Resources Investigations'. Water Resources Management. 12 (1): 31–50. doi:10.1023/A:1007916816469.
- R.J. Oosterbaan. 'DRAINAGE AND HYDROLOGY/SALINITY'(PDF). www.waterlog.info. Retrieved 2016-05-20.
Air Emissions Factors and Quantification
Download free adler 30 mechanics manual for 2005. Released July 1, 2004
(This program supersedes WATER8, Chem9, and Chemdat8, and WATER9 version 1.0)
- WATER9 Support
- WATER9, Version 3.0 - June 29, 2006
WATER9, the wastewater treatment model, is a Windows based computer program and consists of analytical expressions for estimating air emissions of individual waste constituents in wastewater collection, storage, treatment, and disposal facilities; a database listing many of the organic compounds; and procedures for obtaining reports of constituent fates, including air emissions and treatment effectiveness.
WATER9 is a significant upgrade of features previously obtained in the computer programs WATER8, Chem9, and Chemdat8. WATER9 contains a set of model units that can be used together in a project to provide a model for an entire facility. WATER9 is able to evaluate a full facility that contains multiple wastewater inlet streams, multiple collection systems, and complex treatment configurations. WATER9 provides separate emission estimates for each individual compound that is identified as a constituent of the wastes. The emission estimates are based upon the properties of the compound and its concentration in the wastes. To obtain these emission estimates, the user must identify the compounds of interest and provide their concentrations in the wastes. The identification of compounds can be made by selecting them from the database that accompanies the program or by entering new information describing the properties of a compound not contained in the database.
WATER9 has the ability to use site-specific compound property information, and the ability to estimate missing compound property values. Estimates of the total air emissions from the wastes are obtained by summing the estimates for the individual compounds.
The EPA document, AIR EMISSIONS MODELS FOR WASTE AND WASTEWATER includes the equations used in the WATER9 model.
|WATER9 Files for version 2|
|To install WATER9, download the program file, uncompress the file (see explanation of ZIP format under Explanation of File Formats) and then run the resulting setup.exe file.|
|WATER9 Program File - version 2.0|
Single file installation
|WATER9 Program Files for version 2 |
Mulitple file installation. These are smaller files for slower internet connections. Uncompress the files in the same directory (see explanation of ZIP format under Explanation of File Formats) and then run the setup.exe file.
|Water 9 part 1|
Water 9 part 2
Water 9 part 3
Water 9 part 4
|WATER9 Version 2 Changes and Documentation|
|Changes to WATER9 Version 2|
WATER9 version 2 is an update and an upgrade of the previous version of WATER9. New features have been added to improve the use of WATER9.
-More extensive reporting of results,
-an extensive project manual in a compiled help file,
-context sensitive help during WATER9 use,
-improved project editing,
-improved waste spreadsheet editing,
-enhanced recycle property editing,
-additional compounds in the data base,
-upgraded compound property estimation procedures, and
-additional unit types for modeling.
Corrections to WATER9 include:
-correction of display editing errors,
-correction of unit calculations (plug flow aeration and weirs), and
-reviewed and updated compound properties.
Additional information for features, upgrades, and error correction is available in WATER9 under the menu item 'Upgrade information'
Example Scenarios (ZIP 550K)
Example scenario files contain information that will assist you in modeling units with WATER9. A series of example scenarios are provided in the guidance files. Topics include:
-concentrated animal feeding operations,
-municipal treatment with recycle,
-external operations (emissions elsewhere, results merged with WATER9),
-open pipe discharge,
-cross flow cooling tower,
-collection system elements, and
-floating roof tank.
Each guidance topic typically includes:
-an example project,
-a discussion of the technical approach,
-the use of input parameters, and
-comparisons of the model results with measured results (validation).
These guidance files may be used from the WATER9 main menu, or they may be used independently as a Windows help file. If you wish to use these scenarios in WATER9, you must save them to the WATER9 folder that you create when you download the model. You may print the information, search for a topic, or use the contents file.
AIR EMISSIONS MODELS FOR WASTE AND WASTEWATER
EPA-453/R-94-080A - 1994
| (PDF 500K)|
|Explanation of File Formats|
|Go to Software & Tools Index|