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NRCS Definition of Wetlands. Immersed for 7 days or soaked for 14 days amid the developing season at any rate once every 2 years.Inundation means standing water on the surface.Saturated means wet surface by narrow activity.. NRCS Definition of Wetlands. Developing season means between last 28oF in Spring and initial 28oF in the Fall.Each section must be no less than one-half section of land in size. .

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´╗┐WETLANDS Predominance of hydric soils Support hydric vegetation Usually have ponded water no less than 1 to 2 weeks amid the developing season

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NRCS Definition of Wetlands Inundated for 7 days or immersed for 14 days amid the developing season at any rate once at regular intervals. Immersion implies standing water at first glance. Immersed implies wet surface by slender activity.

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NRCS Definition of Wetlands Growing season implies between keep going 28 o F in Spring and initial 28 o F in the Fall. Each section must be no less than one-half section of land in size.

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Benefits of Wetlands A one of a kind untamed life territory Support water based recreational exercises Natural downstream surge control Natural treatment and sifting framework for dirtied water Potential wellspring of ground water energize

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How Wetlands Affect Water Quality Filter out silt and suspended solids Adsorb Chemicals on Organic Matter Absorb Nutrients into Living Plant Tissue Anaerobic Conditions Promote Denitrification Increased Residence Time for Degradation of Pesticides

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Factors Affecting Wetland Water Quality Treatment Hydroperiod: The quantity of days every year that surface water is available. Water Regime: the Frequency, Duration, and Depth of Flooding Soil-Root-Water Interfaces Vegetation Types

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Wetland Vegetation Different Species Prefer Different Environments Hydrologic Nutrient Substrate Conditions

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Desirable Vegetation Traits for Water Treatment Rapid Growth Rate High Tissue Nutrient Content Production of a lot of biomass.

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Loading Factors Affecting Wetland Water Quality Hydraulic Loading: air conditioning in/air conditioning/day 4 BOD 5 and TSS Loadings: lb/air conditioning/day 82 Total Nitrogen: lb/air conditioning/day 3 Retention Time in days 5

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PROBLEMS ASSOCIATED WITH WETLANDS Few monetarily gainful yields develop well on wetlands, including woods Impediment to land types of transportation Most human structures must be based on dry land , including streets Breeding ground for mosquitoes Potential increment in downstream flooding

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Definition of Drainage The administration of abundance water on the land or in the dirt Cropland Recreation Areas Building Foundations Roadways

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Problems Caused by Excess Surface Moisture Impede Surface Traffic Encourage Mosquitoes Contribute to overabundance subsurface dampness

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Problems Caused by Excess Subsurface Moisture Reduced soil air circulation Formation of lethal mixes Reduced root breath and development

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Problems Caused by Excess Subsurface Moisture Reduced soil quality Reduced load conveying limit Increased soil compaction from movement

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Problems Caused by Excess Subsurface Moisture Increased Soil Specific Heat Soil remains cooler longer in the spring Delay the begin of the developing season

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Problems Caused by Excess Subsurface Moisture Reduced Water Infiltration Increased Surface Runoff Increased Soil Erosion

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Benefits of Drainage of Cropland Improved trafficability Increased length of the developing season More effective utilization of soil dampness More proficient utilization of soil supplements More productive utilization of land assets

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Classification of Agricultural Drainage Systems Surface Subsurface Interceptor Relief

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Methods to Improve Land Drainage Reduce surface inflow Improve surface waste Reduce subsurface inflow Improve subsurface seepage

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Drainage Capacity Peak Inflow Rate FLOW RATE volume time Average Flow Rate TIME

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VOIDS SOLIDS SOIL-WATER-AIR Soil is comprised of solids and Voids in dry soil are loaded with air Voids in soaked soil are loaded with water Most roots require no less than 10% air by volume Only subsurface channels can expand soil air volume.

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SURFACE DRAINAGE Are not extremely viable at enhancing soil air circulation Use where soils are too tight for subsurface channels to work Use where outlets are excessively shallow for subsurface channels, making it impossible to work

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Benefits of Surface Drainage Improve Surface Conditions for Field Travel Reduce Mosquito Problems Reduce Infiltration into inadequately depleted soils

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Effects of Surface Drainage on Water Quality Surface Drains diminish invasion and increment surface overflow Improving surface waste decreases the living arrangement time of chemicals on the field Improving surface seepage just may bring about expanded misfortunes of pesticides

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Effects of Surface Drainage on Water Quality Improving surface seepage just as a rule brings about expanded misfortunes of silt Improving surface waste just for the most part results in expanded misfortunes of phosphorus

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SUBSURFACE DRAINAGE Remove gravitational or free water Increase the volume of soil from which roots can get supplements Increase the development and amount of air in the dirt

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BENEFITS OF SUBSURFACE DRAINAGE Providing conditions that allow the dirt to warm up speedier in the spring Increased soil bacterial action Reduced soil disintegration Removing lethal substances from the root zone

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WATER QUALITY IMPACTS OF SUBSURFACE DRAINAGE Reduced loss of dregs Reduced loss of natural matter Reduced loss of potassium and phosphorous Increased loss of nitrate-nitrogen Increased loss of dissolvable salts May make streams go away amid delayed dry climate

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OUTLETS: common streams, waterways, or lakes built waste trench deplete sump with pump outlet

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OUTLETS: The water ought to have the capacity to deplete away openly. Give insurance from disintegration Provide assurance from harm by animals, skimming ice, solidifying and defrosting. Avert passage of tunneling creatures May require conduit on bigger streams

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DEPTH OF SUBSURFACE DRAINS Minimum of 2 feet Never beneath the impenetrable layer unless expected to get least profundity Depths more noteworthy than 6 feet are more costly Increased profundity will permit more extensive dispersing

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SPACING OF SUBSURFACE DRAINS Tight soils require nearer dividing. Nearer dividing will permit quicker expulsion of water Wider separating will diminish the cost of establishment

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GRADES ON SUBSURFACE DRAIN LINES Too level a review will require bigger pipe breadth for a similar execution, and may bring about issues with residue gathering in lines Seldom utilize S < 0.1% Steep review will bring about disintegration and victory issues

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DRAINAGE RATES: Most plans utilize a Drainage Coefficient characterized as a profundity of water to be expelled from the territory in one day (24 hours) Depend on the kind of soil, the sort of product, and the level of surface waste.

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Drainage Coefficients Table 13.2 in the Text Field Crops with Normal Surface Drainage on Mineral Soils 3/8 to 1/2 inch for each day Field Crops with Surface Inlets on Mineral Soils 1/2 to 1 inch for every day

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Drain Capacity A = 100 sections of land D c = 1/2 inch/24 hours

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Drain Pipe Diameter Eq. 13.2, page 242 in Text

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Pipe Diameter Example Q = 2.08 CFS S = 0.1% =0.001 Corrugated Plastic Tubing, n = 0.015

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Pipe Diameter Example Use the Next Largest Size