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58-536: The Anadyr is 1,150 kilometres (710 mi) long and has a basin of 191,000 square kilometres (74,000 sq mi). It is frozen from October to late May and has a maximum flow in June with the snowmelt . It is navigable in small boats for about 570 kilometres (350 mi) to near Markovo . West of Markovo it is in the Anadyr Highlands (moderate mountains and valleys with a few trees) and east of Markovo it moves into

116-932: A local program specifying design requirements, construction practices and maintenance requirements for buildings and properties is in Santa Monica, California . Erosion controls have appeared since medieval times when farmers realized the importance of contour farming to protect soil resources. Beginning in the 1950s these agricultural methods became increasingly more sophisticated. In the 1960s some state and local governments began to focus their efforts on mitigation of construction runoff by requiring builders to implement erosion and sediment controls (ESCs). This included such techniques as: use of straw bales and barriers to slow runoff on slopes, installation of silt fences , programming construction for months that have less rainfall and minimizing extent and duration of exposed graded areas. Montgomery County , Maryland implemented

174-527: A portion of it may infiltrate as it flows overland. Any remaining surface water eventually flows into a receiving water body such as a river , lake , estuary or ocean . Urbanization increases surface runoff by creating more impervious surfaces such as pavement and buildings that do not allow percolation of the water down through the soil to the aquifer . It is instead forced directly into streams or storm water runoff drains , where erosion and siltation can be major problems, even when flooding

232-434: A single water sample and conducting chemical or physical tests on that sample. In the 1950s or earlier, hydrology transport models appeared to calculate quantities of runoff, primarily for flood forecasting . Beginning in the early 1970s, computer models were developed to analyze the transport of runoff carrying water pollutants. These models considered dissolution rates of various chemicals, infiltration into soils, and

290-630: A small time period. Reduced crop productivity usually results from erosion, and these effects are studied in the field of soil conservation . The soil particles carried in runoff vary in size from about 0.001 millimeter to 1.0 millimeter in diameter. Larger particles settle over short transport distances, whereas small particles can be carried over long distances suspended in the water column . Erosion of silty soils that contain smaller particles generates turbidity and diminishes light transmission, which disrupts aquatic ecosystems . Entire sections of countries have been rendered unproductive by erosion. On

348-421: A surface stream without ever passing below the soil surface. It is distinct from direct runoff , which is runoff that reaches surface streams immediately after rainfall or melting snowfall and excludes runoff generated by the melting of snowpack or glaciers. Snow and glacier melt occur only in areas cold enough for these to form permanently. Typically snowmelt will peak in the spring and glacier melt in

406-438: A waste of agricultural chemicals, but also an environmental threat to downstream ecosystems. Pine straws are often used to protect soil from soil erosion and weed growth. However, harvesting these crops may result in the increase of soil erosion. Surface run-off results in a significant amount of economic effects. Pine straws are cost effective ways of dealing with surface run-off. Moreover, Surface run-off can be reused through

464-472: A watercourse is unable to convey the quantity of runoff flowing downstream. The frequency with which this occurs is described by a return period . Flooding is a natural process, which maintains ecosystem composition and processes, but it can also be altered by land use changes such as river engineering. Floods can be both beneficial to societies or cause damage. Agriculture along the Nile floodplain took advantage of

522-450: A well defined channel. Soil surface roughness causes may cause runoff to become concentrated into narrower flow paths: as these incise, the small but well-defined channels which are formed are known as rills. These channels can be as small as one centimeter wide or as large as several meters. If runoff continue to incise and enlarge rills, they may eventually grow to become gullies. Gully erosion can transport large amounts of eroded material in

580-906: Is due to climate change firmly remains a center of debate. Increased water runoff due to snowmelt was a cause of many famous floods. One well-known example is the Red River Flood of 1997, when the Red River of the North in the Red River Valley of the United States and Canada flooded. Flooding in the Red River Valley is augmented by the fact that the river flows north through Winnipeg, Manitoba and into Lake Winnipeg . As snow in Minnesota , North Dakota , and South Dakota begins to melt and flow into

638-442: Is exacerbated by surface runoff, leading to a number of down stream impacts, including nutrient pollution that causes eutrophication . In addition to causing water erosion and pollution, surface runoff in urban areas is a primary cause of urban flooding , which can result in property damage, damp and mold in basements , and street flooding. Surface runoff is defined as precipitation (rain, snow, sleet, or hail ) that reaches

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696-793: Is in turn related to the variability of key patterns of atmospheric circulation. A study of the mountains in the western United States show a region wide decline in spring snow-pack since the mid-1900s, dominated by loss at low elevations where winter temperatures are near freezing. These losses are an indication of increased temperatures which lead to snow loss via some combination of increased regularity of rain versus snow and increased melting during winter months. These natural variations make it challenging to quantify trends with confidence, to deduce observed changes to predict future climate, or to clearly detect changes in snow-pack due to human impact on warming trends. Surface runoff Surface runoff (also known as overland flow or terrestrial runoff )

754-561: Is not. Increased runoff reduces groundwater recharge, thus lowering the water table and making droughts worse, especially for agricultural farmers and others who depend on the water wells . When anthropogenic contaminants are dissolved or suspended in runoff, the human impact is expanded to create water pollution . This pollutant load can reach various receiving waters such as streams, rivers, lakes, estuaries and oceans with resultant water chemistry changes to these water systems and their related ecosystems. As humans continue to alter

812-442: Is otherwise difficult or impossible to obtain because it models the interactions among hydrologic variables (with different probability distributions), resulting in a population of values representing likely long-term outcomes from runoff processes and the potential effects of various mitigation measures. SELDM also provides the means for rapidly doing sensitivity analyses to determine the possible effects of varying input assumptions on

870-455: Is required, to minimize escape of pollutants into sanitary or stormwater sewers . The U.S. Clean Water Act (CWA) requires that local governments in urbanized areas (as defined by the Census Bureau ) obtain stormwater discharge permits for their drainage systems. Essentially this means that the locality must operate a stormwater management program for all surface runoff that enters

928-432: Is the stochastic empirical loading and dilution model (SELDM) is a stormwater quality model. SELDM is designed to transform complex scientific data into meaningful information about the risk of adverse effects of runoff on receiving waters, the potential need for mitigation measures, and the effectiveness of such management measures for reducing these risks. SELDM provides a method for rapid assessment of information that

986-428: Is the difference in energy received from the sun and that reflected by the snowpack because of the snowpack albedo . Longwave radiation is received by the snowpack from many sources, including ozone, carbon dioxide, and water vapor present in all levels of the atmosphere. Longwave radiation is also emitted by the snowpack in the form near- Black-body radiation , where snow has an emissivity between 0.97 and 1.0. Generally

1044-513: Is the unconfined flow of water over the ground surface, in contrast to channel runoff (or stream flow ). It occurs when excess rainwater , stormwater , meltwater , or other sources, can no longer sufficiently rapidly infiltrate in the soil . This can occur when the soil is saturated by water to its full capacity, and the rain arrives more quickly than the soil can absorb it. Surface runoff often occurs because impervious areas (such as roofs and pavement ) do not allow water to soak into

1102-479: Is thinly populated, and is dominated by tundra, with a rich variety of plant life. Much of the region's landscapes are dominated by rugged mountains. For nine months of the year the ground is covered with snow, and the frozen rivers become navigable roads. George Kennan, an American working on the Western Union Telegraph Expedition in the late 1860s, found that dog sled travel on the lower Anadyr

1160-623: The Anadyr Lowlands (very flat treeless tundra with lakes and bogs). The drop from Markovo to the sea is less than 100 feet (30 m). It rises at about 67°N latitude and 171°E longitude in the Anadyr Highlands, near the headwaters of the Maly Anyuy , flows southwest receiving the waters of the rivers Yablon and Yeropol , turns east around the Shchuchy Range and passes Markvovo and

1218-909: The Onemen Bay of the Anadyr Estuary . If the Onemen Bay is considered part of the river, it also receives the Velikaya from the south and the Kanchalan from the north. Other important tributaries are the Yablon, Yeropol and Mamolina from the right and the Chineyveyem and Ubiyenka from the left. Its basin is surrounded by the Amguema and Palyavaam basins to the north, the Bolshoy Anyuy , Oloy and Kolyma basins to

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1276-577: The air and cause earlier melting of snow around them. The snow does not melt slower gradually with distance from the trunk, but creates a wall surrounding snow-free ground around it rather. According to some of sources, North American spring ephermal plants like spring beauty ( Claytonia caroliniana ), trout lily ( Erythronium americanum ) and red trillium (Trillium erectum L.) benefit from such thaw circle. They can emerge earlier inside these circles, what gives them more time before development of tree canopy foliage cutting off significant portion of

1334-434: The soil is saturated and the depression storage filled, and rain continues to fall, the rainfall 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, saturated overland flow, or Dunne runoff. Soil retains a degree of moisture after a rainfall . This residual water moisture affects

1392-489: The 1960s, and early on contact of pesticides with water was known to enhance phytotoxicity . In the case of surface waters, the impacts translate to water pollution , since the streams and rivers have received runoff carrying various chemicals or sediments. When surface waters are used as potable water supplies, they can be compromised regarding health risks and drinking water aesthetics (that is, odor, color and turbidity effects). Contaminated surface waters risk altering

1450-576: The Anadyr river basin. Every year, on the last Sunday in April, there is an ice fishing competition in the frozen estuarine waters of the Anadyr's mouth. This festival is locally known as Korfest . The area is a summering place for a number of migratory birds including brent geese , Eurasian wigeons , and the pintails of California . Snowmelt In hydrology , snowmelt is surface runoff produced from melting snow . It can also be used to describe

1508-501: The Earth's surface; eroded material may be deposited a considerable distance away. There are four main types of soil erosion by water : splash erosion, sheet erosion, rill erosion and gully erosion. Splash erosion is the result of mechanical collision of raindrops with the soil surface: soil particles which are dislodged by the impact then move with the surface runoff. Sheet erosion is the overland transport of sediment by runoff without

1566-540: The Red River, the presence of downstream ice can act as a dam and force upstream water to rise. Colder temperatures downstream can also potentially lead to freezing of water as it flows north, thus augmenting the ice dam problem. Some areas in British Columbia are also prone to snowmelt flooding as well. The date of annual melt is of great interest as a potential indicator of climate change. In order to determine whether

1624-633: The U.S. Resource Conservation and Recovery Act (RCRA) in 1976, and later the Water Quality Act of 1987 , states and cities have become more vigilant in controlling the containment and storage of toxic chemicals, thus preventing releases and leakage. Methods commonly applied are: requirements for double containment of underground storage tanks , registration of hazardous materials usage, reduction in numbers of allowed pesticides and more stringent regulation of fertilizers and herbicides in landscape maintenance. In many industrial cases, pretreatment of wastes

1682-670: The climate through the addition of greenhouse gases to the atmosphere, precipitation patterns are expected to change as the atmospheric capacity for water vapor increases. This will have direct consequences on runoff amounts. Urban runoff is surface runoff of rainwater, landscape irrigation, and car washing created by urbanization . Impervious surfaces ( roads , parking lots and sidewalks ) are constructed during land development . During rain , storms, and other precipitation events, these surfaces (built from materials such as asphalt and concrete ), along with rooftops , carry polluted stormwater to storm drains , instead of allowing

1740-408: The earlier disappearance of spring snow cover in northern Alaska is related to global warming versus an appearance of a more natural, continual cycle of the climate, further study and monitoring is necessary. Large year-to-year variability complicates the picture and furthers the debate. Inter-annual variability of springtime snow pack comes largely from variability of winter month precipitation which

1798-490: The extremely ancient soils of Australia and Southern Africa , proteoid roots with their extremely dense networks of root hairs can absorb so much rainwater as to prevent runoff even with substantial amounts of rainfall. In these regions, even on less infertile cracking clay soils , high amounts of rainfall and potential evaporation are needed to generate any surface runoff, leading to specialised adaptations to extremely variable (usually ephemeral) streams. This occurs when

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1856-404: The fertile top soil and reduces its fertility and quality of the agricultural produce. Modern industrial farming is another major cause of erosion. Over a third of the U.S. Corn Belt has completely lost its topsoil . Switching to no-till practices would reduce soil erosion from U.S. agricultural fields by more than 70 percent. The principal environmental issues associated with runoff are

1914-752: The first local government sediment control program in 1965, and this was followed by a statewide program in Maryland in 1970. Flood control programs as early as the first half of the twentieth century became quantitative in predicting peak flows of riverine systems. Progressively strategies have been developed to minimize peak flows and also to reduce channel velocities. Some of the techniques commonly applied are: provision of holding ponds (also called detention basins or balancing lakes ) to buffer riverine peak flows, use of energy dissipators in channels to reduce stream velocity and land use controls to minimize runoff. Chemical use and handling. Following enactment of

1972-500: The form of water pollution to even more sensitive aquatic habitats. Secondly, runoff can deposit contaminants on pristine soils, creating health or ecological consequences. The other context of agricultural issues involves the transport of agricultural chemicals (nitrates, phosphates, pesticides , herbicides, etc.) via surface runoff. This result occurs when chemical use is excessive or poorly timed with respect to high precipitation. The resulting contaminated runoff represents not only

2030-628: The ground. Furthermore, runoff can occur either through natural or human-made processes. Surface runoff is a major component of the water cycle . It is the primary agent of soil erosion by water . The land area producing runoff that drains to a common point is called a drainage basin . Runoff that occurs on the ground surface before reaching a channel can be a nonpoint source of pollution , as it can carry human-made contaminants or natural forms of pollution (such as rotting leaves). Human-made contaminants in runoff include petroleum , pesticides , fertilizers and others. Much agricultural pollution

2088-422: The growth of elephant mass. In Nigeria , elephant grass is considered to be an economical way in which surface run-off and erosion can be reduced. Also, China has suffered significant impact from surface run-off to most of their economical crops such as vegetables. Therefore, they are known to have implemented a system which reduced loss of nutrients (nitrogen and phosphorus) in soil. Flooding occurs when

2146-399: The high central plateau of Madagascar , approximately ten percent of that country's land area, virtually the entire landscape is devoid of vegetation , with erosive gully furrows typically in excess of 50 meters deep and one kilometer wide. Shifting cultivation is a farming system which sometimes incorporates the slash and burn method in some regions of the world. Erosion causes loss of

2204-492: The impacts to surface water, groundwater and soil through transport of water pollutants to these systems. Ultimately these consequences translate into human health risk, ecosystem disturbance and aesthetic impact to water resources. Some of the contaminants that create the greatest impact to surface waters arising from runoff are petroleum substances, herbicides and fertilizers . Quantitative uptake by surface runoff of pesticides and other contaminants has been studied since

2262-494: The light. They perform nearly all of their yearly photosynthesis during this period. Evergreen trees tend to produce larger thaw circles than deciduous trees. This involves largely a different mechanism and spring ephemeral plants don't occur there. The snow melts earlier in forest also for example on microtopographic mounds (small elevations) or in wet places like edges of creeks or in seeps . These microsites affect distribution of many herbs too. In northern Alaska,

2320-466: The melt-date has advanced by 8 days since the mid-1960s. Decreased snowfall in winter followed by warmer spring conditions seems to be the cause for the advance. In Europe, the 2012 heat wave has especially been anomalous at higher altitudes. For the first time on record, some of the highest Alpine peaks in Europe were snow-free. Although it would seem that the two were related, the question of how much of this

2378-768: The metabolic processes of the aquatic species that they host; these alterations can lead to death, such as fish kills , or alter the balance of populations present. Other specific impacts are on animal mating, spawning, egg and larvae viability, juvenile survival and plant productivity. Some research shows surface runoff of pesticides, such as DDT , can alter the gender of fish species genetically, which transforms male into female fish. Surface runoff occurring within forests can supply lakes with high loads of mineral nitrogen and phosphorus leading to eutrophication . Runoff waters within coniferous forests are also enriched with humic acids and can lead to humification of water bodies Additionally, high standing and young islands in

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2436-786: The most devastating of natural disasters. The use of supplemental irrigation is also recognized as a significant way in which crops such as maize can retain nitrogen fertilizers in soil, resulting in improvement of crop water availability. Mitigation of adverse impacts of runoff can take several forms: Land use controls. Many world regulatory agencies have encouraged research on methods of minimizing total surface runoff by avoiding unnecessary hardscape . Many municipalities have produced guidelines and codes ( zoning and related ordinances ) for land developers that encourage minimum width sidewalks, use of pavers set in earth for driveways and walkways and other design techniques to allow maximum water infiltration in urban settings. An example of

2494-845: The municipal separate storm sewer system ("MS4"). EPA and state regulations and related publications outline six basic components that each local program must contain: Other property owners which operate storm drain systems similar to municipalities, such as state highway systems, universities, military bases and prisons, are also subject to the MS4 permit requirements. Runoff is analyzed by using mathematical models in combination with various water quality sampling methods. Measurements can be made using continuous automated water quality analysis instruments targeted on pollutants such as specific organic or inorganic chemicals , pH , turbidity, etc., or targeted on secondary indicators such as dissolved oxygen . Measurements can also be made in batch form by extracting

2552-493: The need for salt to melt the ice . There are several energy fluxes involved in the melting of snow. These fluxes can act in opposing directions, that is either delivering heat to or removing heat from the snowpack . Ground heat flux is the energy delivered to the snowpack from the soil below by conduction. Radiation inputs to the snowpack include net shortwave (solar radiation including visible and ultraviolet light) and longwave ( infrared ) radiation. Net shortwave radiation

2610-470: The need for Monte Carlo models to simulate stormwater processes because of natural variations in multiple variables affecting runoff quality and quantity. The benefit of the Monte Carlo analysis is not to decrease uncertainty in the input statistics but to represent the different combinations of the variables that determine potential risks of water-quality excursions. One example of this type of stormwater model

2668-407: The net longwave radiation term is negative, meaning a net loss of energy from the snowpack. Latent temperature flux is the energy removed from or delivered to the snowpack which accompanies the mass transfers of evaporation , sublimation , or condensation . Sensible heat flux is the heat flux due to convection between the air and snowpack. Tree trunks absorbing sunlight become warmer than

2726-594: The northwest, and the Penzhina basin to the southwest. In 1648, Semyon Dezhnev reached the mouth of the Anadyr after being shipwrecked on the coast. In 1649, he went upriver and built winter quarters at Anadyrsk. For the next 100 years, the Anadyr was the main route from the Arctic to the Pacific and Kamchatka . In the 18th century, the Anadyr was described by the polar explorer Dmitry Laptev . The country through which it passes

2784-803: The old site of Anadyrsk , turns north and east and receives the Mayn from the south, thereby encircling the Lebediny Zakaznik , turns northeast to receive the Belaya from the north in the Parapol-Belsky Lowlands , then past Ust-Belaya it turns southeast into the Anadyr Lowlands past the Ust-Tanyurer Zakaznik and receives the Tanyurer from the north. At Lake Krasnoye , it turns east and flows into

2842-475: 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 fractions of the annual runoff in a watershed. Predicting snowmelt runoff from a drainage basin may be a part of designing water control projects. Rapid snowmelt can cause flooding . If the snowmelt is then frozen, very dangerous conditions and accidents can occur, introducing

2900-504: The rate of rainfall on a surface exceeds the rate at which water can infiltrate the ground, and any depression storage has already been filled. This is also called Hortonian overland flow (after Robert E. Horton ), or unsaturated overland flow. This more commonly occurs in arid and semi-arid regions, where rainfall intensities are high and the soil infiltration capacity is reduced because of surface sealing , or in urban areas where pavements prevent water from infiltrating. When

2958-484: The seasonal flooding that deposited nutrients beneficial for crops. However, as the number and susceptibility of settlements increase, flooding increasingly becomes a natural hazard. In urban areas, surface runoff is the primary cause of urban flooding , known for its repetitive and costly impact on communities. Adverse impacts span loss of life, property damage, contamination of water supplies, loss of crops, and social dislocation and temporary homelessness. Floods are among

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3016-402: The soil on an up-slope portion of a hill, the water may flow laterally through the soil, and exfiltrate (flow out of the soil) closer to a channel. This is called subsurface return flow or throughflow . As it flows, the amount of runoff may be reduced in a number of possible ways: a small portion of it may evapotranspire ; water may become temporarily stored in microtopographic depressions; and

3074-442: The soil's infiltration capacity . During the next rainfall event, the infiltration capacity will cause the soil to be saturated at a different rate. The higher the level of antecedent soil moisture, the more quickly the soil becomes saturated. Once the soil is saturated, runoff occurs. Therefore, surface runoff is a significantly factor in the controlling of soil moisture after medium and low intensity storms. After water infiltrates

3132-470: The summer, leading to pronounced flow maxima in rivers affected by them. The determining factor of the rate of melting of snow or glaciers is both air temperature and the duration of sunlight. In high mountain regions, streams frequently rise on sunny days and fall on cloudy ones for this reason. 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

3190-579: The tropics and subtropics can undergo high soil erosion rates and also contribute large material fluxes to the coastal ocean. Such land derived runoff of sediment nutrients, carbon, and contaminants can have large impacts on global biogeochemical cycles and marine and coastal ecosystems. In the case of groundwater, the main issue is contamination of drinking water, if the aquifer is abstracted for human use. Regarding soil contamination , runoff waters can have two important pathways of concern. Firstly, runoff water can extract soil contaminants and carry them in

3248-550: The ultimate pollutant load delivered to receiving waters . One of the earliest models addressing chemical dissolution in runoff and resulting transport was developed in the early 1970s under contract to the United States Environmental Protection Agency (EPA). This computer model formed the basis of much of the mitigation study that led to strategies for land use and chemical handling controls. Increasingly, stormwater practitioners have recognized

3306-489: The water to percolate through soil . This causes lowering of the water table (because groundwater recharge is lessened) and flooding since the amount of water that remains on the surface is greater. Most municipal storm sewer systems discharge untreated stormwater to streams , rivers , and bays . This excess water can also make its way into people's properties through basement backups and seepage through building wall and floors. Surface runoff can cause erosion of

3364-417: Was limited by lack of firewood. Reindeer , upon which the local inhabitants subsisted, were once found in considerable numbers, but the domestic reindeer population has collapsed dramatically since the reorganization and privatization of state-run collective farms beginning in 1992. As herds of domestic reindeer have declined, herds of wild caribou have increased. There are ten species of salmon inhabiting

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