wiktionary run off run off runoff Run off or runoff may refer to RUNOFF , the first computer text formatting program, running on the CTSS operating system Runoff program , the type setting program on the Multics operating system Runoff model reservoir , a mathematical model describing the rainfall runoff relations of a rainfall catchment area or watershed Run off area , an area on a racetrack for racer safety Runoff curve number , an empirical parameter used in hydrology Runoff voting or Two round system , a voting system used to elect a single winner, whereby only two candidates from the first round continue to the second round Instant runoff voting , an electoral system in which voters rank the candidates in order of preference Surface runoff , the flow of water, from rain, snow melt, or other sources, over land Bleed printing , printing that goes beyond the edge of the sheet after trimming See also intitle Runoff OR Run off OR Run off All pages with titles containing Runoff or Run off or Run off . disambiguation ... more details
Unimpaired runoff , also known as full natural flow , is a hydrology term that is used to describe the natural Surface runoffrunoff of a Drainage basin watershed or waterbody that would have occurred prior to human impact on the environment anthropogenic or human influences on the watershed. Flow readings from river gauge s are influenced by Source river or stream upstream diversion s, impoundments, and many other alternations of the land that drains into a watershed or of alternatives of a river channel itself. Engineers estimate unimparied or natural runoff by estimating all of the effects of human impairments to flow and then removing these effects. Since these calculation s involve many assumptions, they tend to be more accurate for either smaller watersheds or when expressed as longer period averages. Unimpaired runoff is important for legal and scientific reasons. Since human development continues to alter watersheds, unimparied runoff provide fixed frames of references for flow rates. The reason unimpaired runoff is important is because long term hydrologic records are often used to develop relationships between Precipitation meteorology precipitation , runoff, and water supply. By removing changes in the timing between precipitation and runoff due to human influences, the long term relationships will be more useful. Calculating unimparied runoff is also extremely important in identifying long term climate change impacts. By subtracting the known human influences on a long term hydrologic record, the records may still show signs of a long term change. These long term signals are sometimes described as long term climate change. It is still possible that the long term climate signal is caused by larger scale antropogenic sources. Examples of Use Unimpaired runoff calculations are used extensively in western United States states such as California for water resources ... indexes. The following is a list of some examples of use of unimpaired runoff calculations Sacramento ... more details
Runoff voting can refer to Two round system , a voting system used to elect a single winner, whereby only two candidates from the first round continue to the second round Instant runoff voting , an electoral system whereby voters rank the candidates in order of preference Contingent vote , a two round system of instant runoff voting. Exhaustive ballot , a reiterative voting system whereby rounds of voting continue with or without elimination until one candidate achieves a majority, also called repeated balloting Disambig ... more details
Unreferenced stub auto yes date December 2009 Lowercase runoffrunoff was the text formatting computer program program on the Multics operating system . It was a descendant of the RUNOFF type setting program from Compatible Time Sharing System CTSS and was originally written by Jerome H. Saltzer . Robert Morris cryptographer Bob Morris and Doug McIlroy translated that from MAD assembler to BCPL they then moved the BCPL version to Multics when the IBM 7094 on which CTSS ran was being shut down. A later version of runoff for Multics was written in PL I by Dennis Capps, in 1974. This runoff code was the ancestor of the machine language roff that was written for the fledgling Unix . Other versions of Runoff were developed for various computer systems including Digital Equipment Corporation s PDP 11 minicomputer systems running RT 11 , RSTS E , RSX 11 RSX on Digital s PDP 10 and for OpenVMS on VAX minicomputers, as well as Sperry Unisys Univac 90 60 mainframe using the EDT text editor EDT text editor under the VS 9 operating system . These different releases of Runoff typically had had little or no relationship to each other in terms of how formatting commands and arrangement of text was performed except that they all used the convention of separating presentation text from Runoff commands by indicating a command to Runoff by beginning the line with a period. External links cite book last Honeywell Bull, Inc. title Multics Commands and Active Functions AG92 06 url http www.bitsavers.org pdf honeywell multics AG92 06B multicsCmds Nov87.pdf accessdate Feb 23, 2012 date Feb, 1985 pages 3 822 to 3 842 DEFAULTSORT Runoff Program Category Word processors Category Troff digital typography stub ... more details
RUNOFF was the first computer text formatting computer program program to see significant use. It was written in 1964 for the Compatible Time Sharing System CTSS operating system by Jerome H. Saltzer in MAD programming language MAD Assembly language assembler . It actually consisted of a pair of programs, TYPSET which was basically a document editor , and RUNOFF the output processor . RUNOFF had support for pagination and headers, as well as text justification typesetting justification TJ 2 appears to have been the earliest text justification system, but it did not have the other capabilities . RUNOFF is a direct predecessor of the runoff program runoff document formatting program of Multics , which in turn was the ancestor of the roff and nroff document formatting programs of Unix , and their descendants. It was also the ancestor of FORMAT for the IBM System 360 , and of course indirectly for every computerized word processing system. Likewise, RUNOFF for CTSS was the predecessor of the various RUNOFFs for Digital Equipment Corporation DEC s operating systems, via the RUNOFF developed by the University of California, Berkeley University of California, Berkeley s Project Genie for the Scientific Data Systems SDS SDS 940 940 system. ref cite newsgroup title Re Runoffs was TJ 2, a very early word processor like program for the PDP 1 author John V. Everett date 1997 02 08 newsgroup ... accessdate 2008 11 14 ref ref cite book last Barnes first Larry title RUNOFF A Program ... 244.html TYPSET and RUNOFF Memorandum editor and type out commands MIT Computation Center CC 244, Project ... Manuscript typing and editing TYPSET, RUNOFF Section AH.9.01, CTSS Programmer s Guide, Project ... publications PSN 40.html Experimental Additions to the RUNOFF Command Programming Staff Note 40, Project MAC, Cambridge, 1965 DEFAULTSORT Typset And Runoff Category Word processors Category Troff Category History of software digital typography stub es RUNOFF ... more details
Image Runoff.jpg thumb Runoff flowing into a storm drain stormwater drain Surface runoff is the water ... Processes, Wiley Intersciences DOI 10 1002 hyp 5740 2004 ref Runoff that occurs on surfaces before ... . If a nonpoint source contains man made contaminants, the runoff is called nonpoint source pollution . A land area which produces runoff that drains to a common point is called a drainage basin . When runoff flows along the ground, it can pick up Soil contamination soil contaminants including, but not limited ... Surface runoff from a hillside after soil is saturated Surface runoff can be generated either by rainfall .... In areas where there is no snow, runoff will come from rainfall. However, not all rainfall will produce runoff because storage from soils can absorb light showers. On the extremely ancient soils of Australia and Southern Africa , ref McMahon T.A. and Finlayson, B. Global Runoff Continental Comparisons ... hairs can absorb so much rainwater as to prevent runoff even when substantial amounts of rain ... and potential evaporation are needed to generate any surface runoff, leading to specialised adaptations ... will immediately produce surface runoff. The level of antecedent soil moisture is one factor affecting the time until soil becomes saturated. This runoff is called saturation excess overland flow or saturated overland flow. It is also known as Hewlettian runoff. Antecedent soil moisture Soil retains ... becomes saturated. Once the soil is saturated, runoff occurs. Subsurface return flow After water ... or throughflow . As it flows, the amount of runoff may be reduced in a number of possible ways a small ... infiltration of runoff as it flows overland. Any remaining surface water eventually flows into a surface ... 200px thumb Urban surface water runoff Urbanization increases surface runoff, by creating more impervious ... drain storm water runoff drains , where erosion and siltation can be major problems, even when flooding is not. Increased runoff reduces groundwater recharge, thus lowering the water table and making ... more details
Image Storm Drain.JPG thumb Urban runoff flowing into a storm drain Urban runoff is surface runoff of rainwater created by urbanization . This runoff is a major source of water pollution in urban communities ... between impervious surfaces and surface runoff Impervious surfaces road s, parking lot s and sidewalk ... Runoff Quality Management. WEF Manual of Practice No. 23 ASCE Manual and Report on Engineering Practice ..., to stream s, river s and bay s. Pollutants in urban runoff Image Pollutedflood.JPG thumb A creek filled with urban runoff after a storm Water running off these impervious surfaces tends to pick ... runoff contributes high levels of chemical synthesis synthetic organic compound s and zinc from ... source of nitrates and phosphorus in urban runoff. ref name ASCE1 ref cite book title ... five times the runoff of a typical woodland of the same size. ref name EPA2 U.S. Environmental Protection ... Water Quality from Urban Runoff. Document No. EPA 841 F 03 003. February 2003. ref div style clear left Effects of urban runoff A 2008 report by the United States National Research Council textbox below identified urban runoff as a leading source of water quality problems. blockquote class toccolours ... channelized with concrete walls to control localized flooding. The runoff also increases temperatures in streams, harming fish and other organisms. A sudden burst of runoff from a rainstorm can cause ... quality Urban runoff. Accessed 2009 12 30. ref One of the most pronounced effects of urban runoff ... runoff creates an unnatural year round streamflow that hurts the vegetation, wildlife and stream ... to water, urban runoff rushes down the stream channel, ruining natural features such as meander s and sandbar ..., urban runoff carries trash, pollutants, excessive silt, and other wastes, and can pose moderate to severe health hazards. Because of fertilizer and organic waste that urban runoff often carries, eutrophication often occurs in waterways affected by this type of runoff. After heavy rains, organic ... more details
The runoff curve number also called a curve number or simply CN is an empirical parameter used in hydrology for predicting direct Surface runoffrunoff or Infiltration hydrology infiltration from Rain rainfall excess. ref name usda86 cite book author United States Department of Agriculture title Urban hydrology for small watersheds year 1986 edition Second Edition series Technical Release 55 TR 55 ... Service or SCS the number is still popularly known as a SCS runoff curve number in the literature. The runoff curve number was developed from an empirical method empirical analysis of runoff from ... method for determining the approximate amount of direct runoff from a Precipitation meteorology rainfall event in a particular area. The runoff curve number is based on the area s hydrologic soil group ... the runoff curve numbers for characteristic land cover descriptions and a hydrologic soil group. The runoff equation is math Q frac P I a 2 P I a S math where math Q math is Surface runoffrunoff ... after runoff begins L in math I a math is the initial abstraction L in , or the amount of water before runoff, such as Infiltration hydrology infiltration , or rainfall interception by vegetation and it is generally assumed that math I a 0.2S math The runoff curve number, math CN math , is then related ... runoff potential while larger numbers are for increasing runoff potential. The lower the curve number, the more permeable the soil is. Antecedent moisture condition AMC adjustment Runoff is affected ... are less than 1 reduce math CN math and potential runoff , while math CN III math factor are greater than 1 increase math CN math and potential runoff . The AMC factors can be looked up in a reference table. ref name usda86 References references See also Hydrological modelling Runoff model reservoir External links http www.lmnoeng.com Hydrology hydrology.htm SCS TR 55 Peak Discharge and Runoff ... Runoff Curve Number Method Category Hydrology Category Soil physics cs Metoda CN k ivek de Abflussbeiwert ... more details
in urban runoff... Copper is suggested to be the most significant nowiki threat nowiki of the three. Coliform bacteria are present at high levels in urban runoff. Nutrients are generally present in urban runoff, but... nowiki generally nowiki concentrations do not appear to be high in comparison with other ... runoff at concentrations approximating those in secondary treatment plant discharges. The physical aspects of urban runoff, e.g. erosion and scour, can be a significant cause of habitat disruption ... are capable of providing very effective removal of pollutants in urban runoff. retention basin Wet ... wetland Wetlands are considered to be a promising technique for control of urban runoff quality ... Urban Runoff Program Executive Summary. Water Planning Division. December 1983. ref ... for improving the quality of urban runoff. In 1987, the results of the report were used ... from stormwater runoff as it is detained, and that are designed to perform to the level of the more ... more details
A runoff model is a mathematical model describing the rainfall Surface runoffrunoff relations of a rainfall catchment area , drainage basin or watershed . More precisely, it produces the surface runoff ... of rainfall into runoff. br A well known runoff model is the linear reservoir , but in practice it has limited applicability. br The runoff model with a non linear reservoir is more universally ... area is too large, it can be divided into sub catchments and the various runoff hydrographs may be combined using flood routing techniques. br File Water cycle.png thumb 250px Rainfall runoff models .... Hydrograph analysis for areas with mainly groundwater runoff . In Drainage Principle and Applications, Vol. II, Chapter 16, Theories of field drainage and watershed runoff. p 321 358. Publication 16 ... continuity or water balance equation R Q dS dT , with units L T where br Q is the runoff or discharge ... or small increment of S br dT is a differential or small increment of T Runoff equation br A combination ... &minus A T2 &minus T1 R 1 &minus exp &minus A T2 &minus T1 This is the runoff equation or discharge ... of time steps and computing, with the runoff equation , the runoff at the end of each time step from the runoff at the end of the previous time step. Unit hydrograph br The discharge may also be expressed ... unit hydrograph IUH because the Q herein equals Q2 of the foregoing runoff equation using R 0 ... runoff equation eliminates the necessity of calculating the total hydrograph by the summation .... ref D.A. Kraijenhoff van de Leur, 1973. Rainfall runoff relations and computational models . In Drainage Principle and Applications, Vol. II, Chapter 16, Theories of field drainage and watershed runoff ... A can be determined from a data record of rainfall and runoff using the method explained below under ... rainfall or recharge, i.e. when R 0, the runoff equation reduces to Q2 Q1 exp &minus Aq T2 &minus ... or response factor Aq can be determined from runoff or discharge measurements using unit ... more details
Like virtually all voting system electoral system s, in Two round system runoff voting there is potential for both tactical voting and strategic nomination . ref The Gibbard Satterthwaite theorem shows that any voting method which does not allow tactical voting must be either dictatorial or non deterministic ... preferences, but instead vote insincerely in an attempt to influence the result. Runoff voting is intended ... extra candidates or withdrawing a candidate who would otherwise have stood. Runoff is intended ... strategic nomination and tactical voting in runoff voting was the French presidential election, 2002 ... Pie and Fruit. Runoff voting is used to find the winner. Round 1 In the first round of voting each .... Tactical voting Runoff voting attempts to reduce the potential for tactical voting by eliminating ... a vote for any other candidate will not affect the result. Under runoff voting this tactic, known as compromising ... be used in runoff voting because it is sometimes necessary to compromise as a way of influencing which ... effective because runoff voting eliminates many candidates in the first round, and these often ... tactically. In this example, therefore, runoff voting removes the potential for tactical voting that would ... main Strategic nomination Runoff voting can be influenced by strategic nomination this is where ... candidates or withdrawing a candidate who would otherwise have stood. Runoff voting is vulnerable to strategic ... and prevents any candidate acceptable to them from surviving to the last round. Runoff votings ... to that point. In runoff voting voters can counteract the effect of vote splitting in the first round ... to strategic nomination than runoff voting. 2002 French presidential election main French presidential ... of both tactical voting and strategic nomination in runoff voting. The three main candidates were Jacque ... Duke lost to the more moderate Edwin Edwards . Louisiana uses a form of runoff voting called the run off primary election . Note references Category Runoff voting Category Voting theory ... more details
Image Preferential ballot.svg right thumb Example instant runoff voting ballot Electoral systems Instant runoff voting IRV , also known as the alternative vote AV or transferable voting , is an voting ... combined, and then that candidate is declared the winner. Instant runoff voting is used to elect ... Oakland, California ref name or2010 cite web url http oaklandrising.org campaign instant runoff voting title Oakland Rising Instant Runoff Voting publisher oaklandrising.com year 2010 accessdate ... minnesota.publicradio.org display web 2009 05 10 instant runoff voting excercises election judge fingers Instant runoff voting exercises election judge fingers Minnesota Public Radio, 10 May 2009 ref ... In the United States, instant runoff voting is an umbrella term associated with ranked choice elections ... instant runoff is used because the method approximates a series of runoff elections tallied in rounds .... ref except voters may not change their preference between rounds. Instant runoff voting has a number ... it instant runoff voting because it resembles Two round system runoff voting . The British usually ... its inventor, American William Robert Ware . North Carolina law uses instant runoff to describe the contingent ... produces the top two candidates for a runoff election. ref cite web url http www.ncleg.net ... date accessdate 6 May 2010 ref Election officials in Hendersonville, North Carolina use instant runoff ...?blog 10&title no instant runoff in hendersonville&more 1&c 1&tb 1&pb 1 title CITIZEN TIMES Capital Letters Post details No instant runoff in Hendersonville publisher Blogs.citizen times.com date ... bills 2005 public HB1770.pdf Dead link date May 2010 ref use instant runoff to describe the practice of having certain categories of absentee voters cast ranked ballots before the first round of a runoff that are then counted in a runoff election. When the single transferable vote STV system is applied ... its president by IRV and parliamentary seats by STV. History Main History and use of instant runoff ... more details
Instant runoff voting IRV has been used on and off in the United States in various jurisdictions since ... by other primary election reforms, including the use of a second, or runoff primary in the event ... aa irv01.htm Instant Runoff Voting History in Ann Arbor, Michigan Bot generated title ref Since 2002 ... generated title ref won 55 of the vote in making instant runoff voting the means of electing candidates ... have arrived before running instant runoff ballot counts. Results Ranked Choice Voting has been ...?storyId 3864851 San Francisco Adopts Instant Runoff Elections , Richard Gonzales, National Public ... results There were four elections that used the instant runoff process after no majority winner ... total ballots. 2005 San Francisco results There was one election requiring the instant runoff process ... Board of Supervisors elections, 2006 two elections that required the instant runoff process, districts ... divided among the 3 runners up, and 1.64 exhausted ballots. The detailed runoff results for district ... choice voting ref Basalt, Colorado The city of Basalt, Colorado adopted instant runoff voting in 2002 ... basalt 00a.pdf ref The city is ready to run instant runoff elections, but the 2004 and 2008 elections ... title ref Ferndale, Michigan The city of Ferndale, Michigan passed 68 instant runoff voting in 2004 ... instant runoff voting in 2004. ref http www.ippn.org article.php?ID winternews05c.html Instant Runoff ... access 1975028861.html?FMT ABS work The Burlington Free Press first John last Briggs title Instant runoff ... rejects instant runoff voting date March 4, 2010 ref The repeal reverts the system back to a 40 rule that requires a top two runoff if no candidate exceeds 40 of the vote. Had the 2009 election occurred under these rules, Kiss and Wright would have advanced to the runoff. If the same voters had participated in the runoff as in the first election and not changed their preferences, Kiss would have won the runoff. ref http www.ci.burlington.vt.us ct elections irv FAQ 5. for IRV Under the old pre ... more details
Instant runoff voting , more commonly known outside the USA as the alternative vote or preferential voting, was devised around 1870 by the US architect William Robert Ware W. R. Ware . Today it is in use at a national level to elect the Australian House of Representatives , the House of Representatives Fiji Fijian House of Representatives , the President of Ireland and President of India . In Australia it is also used for elections to the legislative assembly legislative assemblies lower house s of all states and territories except Tasmania and the Australian Capital Territory , and for the Tasmanian Legislative Council upper house . IRV is also used a number of municipal elections in Australia, the United States, and New Zealand . Because of its relationship to the Single Transferable Vote STV system, IRV is used for by elections in a some jurisdictions that use STV for ordinary parliamentary elections, such as the Republic of Ireland and Scotland . IRV is known by different names in the various countries in which it is used. It is also known as the Alternative Vote , Ranked Choice Voting , Preferential Voting , and the Hare system . The last three of these names may be misleading ... system known as instant runoff voting was invented by Ware rather than Thomas Hare political scientist Thomas Hare . History Instant runoff voting is based on the Single Transferable Vote electoral ... instant runoff. The number of candidates who depended on preferences to win was 76 more than half ... to as instant runoff voting and only rarely as the Alternative Vote , the name popular in Great Britain ..., the Speaker s Conference advocated the adoption of instant runoff for 358 of the 569 constituencies ... a mayor directly, these cities used instant runoff voting for instance, in 2007 Wellington s mayor ... election References reflist DEFAULTSORT History And Use Of Instant Runoff Voting Category Instant runoff voting Category History of electoral systems Category Use of electoral systems ... more details
Merge to Instant runoff voting date April 2011 Globalize UK date June 2011 This article is a comparison of various voting systems with Instant runoff voting IRV , also called the Alternative Vote , preferential voting and ranked choice voting. Categories Voting systems fall into three broad types. ref name PRtypes cite web url http www.mtholyoke.edu acad polit damy BeginnningReading types.htm title Types of Voting Systems publisher Mtholyoke.edu date 8 April 2005 accessdate 6 May 2010 ref Plurality majority systems, ref name PRtypes sometimes called majoritarian . Proportional representation systems, ref name PRtypes sometimes called proportional . Semiproportional systems. ref name PRtypes The types of various legislatures and their voting systems are given below. class wikitable Voting system First past the post voting FPTP Alternative Vote AV Single Transferable Vote STV Party list proportional representation PRO Parallel voting Parallel Notes Category style background ff9090 Majoritarian ref name PRtypes style background ff9090 Majoritarian ref name PRtypes style background 90ff90 Proportional ref name PRtypes style background 90ff90 Proportional ref name PRtypes style background ff9090 Semi proportional ref name PRtypes Example legislature United Kingdom UK House of Commons of the United ... Instant runoff voting , IRV and Two round system s of runoffs, RO. Because both systems involve ... Lime First past the post voting FPTP br style background Pink Instant runoff voting IRV br ... background Lime Two round system Two br round br runoff br style background Yellow Schulze method ... the post voting FPTP style background Pink Instant runoff voting IRV style background Lime Approval ... br runoff style background Yellow Schulze method Schulze br ref name schulze1 style background Pink ... IRV InstantRunoffVotingFlaws.pdf title Realities mar Instant Runoff Voting publisher Kathy Dopp date ... raised their second choice to first choice, the Condorcet winner would have won the instant runoff ... more details
Hare method , named for Thomas Hare, may refer to two related voting systems Instant runoff voting for single seat elections Hare method STV for electing multi seat constituencies. disambig ... more details
otheruses Run On disambiguation In hydrology , run on refers both to the process whereby surface runoff infiltration hydrology infiltrates the ground as it flows, and to the portion of runoff that infiltrates. Run on is common in arid and semi arid areas with patchy vegetation cover and short but intense thunderstorms . In these environments, surface runoff is usually generated by a failure of rainfall to infiltrate into the ground quickly enough this runoff is termed infiltration excess overland flow . This is more likely to occur on bare soil , with low infiltration capacity . As runoff flows downslope, it may flow onto ground with higher infiltration capacity such as beneath vegetation and become run on. Run on is an important process in the hydrological and ecohydrology ecohydrological behaviour of semi arid ecosystems. Tiger bush is an example of a vegetation community that develops a patterned structure in response to, in part, the generation of runoff and run on. See also Stormwater References refbegin cite journal last1 Corradini first1 C. last2 Morbidelli first2 R. last3 Melone first3 F. year 1998 title On the interaction between infiltration and Hortonian runoff journal Journal of Hydrology publisher volume 204 issue 1 4 pages 52 67 url issn 0022 1694 doi 10.1016 S0022 1694 97 00100 5 refend ecology stub Category Hydrology ... more details
Drainage model may refer to a surface drainage model or rainfall runoff model see surface runoff , runoff model reservoir , or a http www.waterlog.info software.htm software site providing free download of a conceptual rainfall runoff model RainOff based on a nonlinear reservoir a subsurface groundwater , drainage model related to a spacing equation for subsurface pipe drains and open ditches horizontal drainage or wells vertical drainage see watertable control , or a http www.waterlog.info software.htm software site providing free download of a drain spacing equation EnDrain using the groundwater energy balance , and a well drainage well spacing equation WellDrain . a hydrological subsurface drainage model see soil salinity control for an example of an agro hydro salinity subsurface drainage model SaltMod groundwater flow in the aquifer see groundwater model or an example of an agro hydro salinity groundwater model SahysMod disambig Category Hydrology ... more details
Wiktionary Inflow may refer to Inflow hydrology In hydrology, the source of the water in a body of water Infiltration Inflow , inappropriate connection of surface runoff drains into sanitary sewers Inflow meteorology , air that flows inwards to a thunderstorm disambig ... more details
GRDC may refer to Geographic Resources for Development Center , Nigeria Geological Research and Development Center , Indonesia Georgian Reconstruction and Development Company , Georgia Grains Research and Development Corporation , Australia Global Runoff Data Centre , Germany disambig ... more details
Land drainage may refer to Surface drainage of the land Drainage system geomorphology , pattern of natural drains, streams, rivers, etc. Surface runoff , surface runoff of excess rainfall from the land Drainage system agriculture , land forming or land shaping to enhance the drainage from the soil surface in agricultural land Contour plowing , controlling runoff and soil erosion Subsurface groundwater drainage Horizontal drainage by pipes and ditches Drainage Tile drainage Watertable control Vertical drainage by wells Well drainage Watertable control disambig Category Hydrology Category Land management ... more details
Unreferenced date February 2007 orphan date November 2009 Snow filtration is a system to deal with left over snow in an environmentally friendly way. Snow removal Snow is removed from roads is done to ensure road safety . Roads are salted to cause the snow to melt on the road so that it doesn t freeze after melting. The conventional method is by dumping the snow into rivers, which increases the salt concentration in the water. Method In spring, as snow melts the salt that was put on it is left behind, which can be environmentally damaging as it creates a Tonicity Hypertonicity hypertonic environment for plants that are affected. The snow Surface runoff runoff is collected and brought to a collection center. It is directed through an oil and grit separator which also monitors the consistency of pollutants in the runoff. The oil and grit separator causes electrochemical and biological process biological processes, which bind heavy metals and nutrients to the sediment through the process of redox . At the same time, this reduces the amount of chlorine present in the runoff. The runoff then flows into a catch basin , where plants use the salt ions e.g. Potassium K sup sup , Phosphorus P sup 3 sup , Nitrogen N sup 3 sup for their growth. The salts are absorbed by the plants which filtrate further, leaving only clean water to go back into streams and rivers . DEFAULTSORT Snow Filtration Category Sustainable technologies Environment stub ... more details
Image Runoff of soil & fertilizer.jpg thumb right Nutrient pollution caused by Surface runoffrunoff of soil and fertilizer during a rain storm Nutrient pollution, a form of water pollution , refers to contamination by excessive inputs of nutrient. It is a primary cause of eutrophication of surface water s, in which excess nutrients, usually nitrogen or phosphorus , stimulate algae algal growth. Sources of nutrient pollution include surface runoffrunoff from farm fields and pastures, discharges from septic tank s and feedlot s, and air pollution emissions from combustion. See also Agricultural wastewater treatment Nonpoint source pollution Water quality References CRS article Report for Congress Agriculture A Glossary of Terms, Programs, and Laws, 2005 Edition url http ncseonline.org nle crsreports 05jun 97 905.pdf author Jasper Womach U.S. Environmental Protection Agency EPA . Washington, DC. http www.epa.gov owow nps Ag Runoff Fact Sheet.pdf Protecting Water Quality from Agricultural Runoff. March 2005. Document No. EPA 841 F 05 001. External links http www.extension.org pages Environmental Impacts and Benefits of Manure Phosphorous and Surface Water Protection Environmental Impacts and Benefits of Manure focuses on phosphorus and water quality. Part of the http www.extension.org pages Manure Nutrient Management Articles manure nutrient management section of the http www.extension.org pages animal manure management Livestock and Poultry Environmental Learning Center . marine pollution Category Agricultural soil science Category Sustainable agriculture Category Fertilizers Category Organic gardening Category Environmental soil science Category Water pollution ar ... more details
thumb 150px left Surface water cycle Runoff model empirical main Runoff model empirical These models use an empirical method to convert rainfall volume into runoff volume. An example is the Runoff ... ftp.wcc.nrcs.usda.gov downloads hydrology hydraulics tr55 tr55.pdf pages ref br The runoff curve ... direct runoff or infiltration from rainfall excess. It can be used with a Hydrograph Unit Hydrograph unit hydrograph to derive the runoff rate from the direct runoff by convolution . Runoff model reservoir main Runoff model reservoir These models describe rainfall runoff relations using the concept of a non linear reservoir. ref RainOff http www.waterlog.info rainoff.htm a rainfall runoff model ... HBV hydrology model HBV , which is combines an Runoff model empirical empirical runoff model and a hydrological ... with a groundwater model . See also Surface runoff Hydrology agriculture Aquifer Groundwater model ... more details
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