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Training Outline Background/Orientation – Pat Willey – Portland, OR WQQT Drainage Systems – Hamid Farahani – Greensboro, NC ENTSC DWM for Subsurface Systems – Ruth Book, SCE, Champaign, IL DWM for Surface Systems – Jerry Walker, Ft. Worth, TX CNTSC Wrap Up – Hamid Farahani Ag Drainage Water Management Webinar August 2011

Drainage Water Management - Background/Orientation 1.MRBI Team and Ag Water Management Team 2.Basics of DWM 3.Downstream environmental impacts of Nitrogen and Phosphorus – environmental issues – health issues 4.DWM requirement in N-Strategy 590 (where do we have to have it?) Ag Drainage Water Management Webinar August 2011

Mississippi River Basin Initiative Team Focus Area: Mississippi River Basin (AR, KY, IL, IN, IA, LA, MN, MS, MO, OH, TN, and WI) MRBI Goal: Improve Water Quality and wildlife habitat through: Cooperative Conservation Partnership Initiative Wetlands Reserve Enhancement Program (WREP), Conservation Innovation Grants (CIG), and other programs Ag Drainage Water Management Webinar

Senior Project Leader: Paul Sweeney Team Membership are from the following: NHQ Disciplines NHQ Program Specialists NTSC Representatives NRCS States Team Advisors: (ARS, Purdue and NCSU) Ag Water Management Team Ag Drainage Water Management Webinar August 2011

Ag Water Management Team Scope is National Initial focus: Upper Mississippi River Basin Goal : reduce nitrate (NO 3 -1 ) loading to streams reduce and ag. impact on Gulf of Mexico hypoxia How: Implement DWM to reduce NO 3 -1 leaving drained farmlands

What is Drainage Water Management (DWM)? DWM- Practice Standard code 554 -Employment of a Structure for Water Control (code 587) in the drainage line to provide capability to manage the flow from an agricultural drainage system. DWM typically: Involves raising the outlet elevation of a drain Results in reduced flow from the outlet Ag Drainage Water Management Webinar August 2011

Do structures eliminate flow from the drain outlet? Maybe… When the outlet is initially raised, outflows may stop. As flow continues to enter the drain upstream from the structure, the water table rises. Once the water level rises to the elevation of the raised outlet, any additional rise in the water table results in discharge to the outlet. Ag Drainage Water Management Webinar August 2011

How can DWM help? DWM has been shown to reduce stream loading of nitrates by agricultural drain systems How much reduction in N-loading? Reductions of 40% to 50% in nitrate have been achieved Reductions are in proportion to reduction in drainage water out-flow (a 50% reduction in outflow may achieve a 40 to 50% reduction in N-load) Ag Drainage Water Management Webinar August 2011

Why are we focusing on DWM? NRCS recognizes nutrient loading to streams as a national concern Drainage water has been identified as a significant source of nutrient loads Impacts to Gulf of Mexico and other receiving waters are significant Ag Drainage Water Management Webinar August 2011

Does DWM affect crop growth? DWM on annual crops during the non-growing season does not adversely affect crop production Some production benefits may be observed by managing an elevated water table in the field during the growing season. Results are not statistically conclusive. Ag Drainage Water Management Webinar August 2011

NRCS Expectations for DWM It is about management… not about draining new acres Focus is to manage drainage water for improved environmental outcomes and sustaining crop production Use a conservation systems approach—ADWM with nutrient management, conservation tillage, crop rotations, cover crops, etc. Consideration must be given to neighboring or downstream hydrologic effects —offsite lateral seepage, stream flows, flooding, groundwater Ag Drainage Water Management Webinar August 2011

Environmental Impacts of Excessive Nutrients Hypoxia Drinking Water Quality Ag Drainage Water Management Webinar August 2011

Hypoxia – the condition in which dissolved oxygen is below the level necessary to sustain most aquatic animal life. Where is it a problem? Notable hypoxic zones in the United States: Gulf of Mexico Chesapeake Bay What is Hypoxia? Ag Drainage Water Management Webinar August 2011

What causes Hypoxia? Ag Drainage Water Management Webinar August 2011

Major process for hypoxia development of hypoxia in the Gulf of Mexico 1.Nutrient loading (nitrogen and phosphorus) to the Gulf by the Mississippi River (Mississippi provides 90% of fresh inflow to GoM) 2.Nutrient-enhanced primary production (enhanced growth of aquatic plants and protists (e.g. algae, diatoms) in the Gulf of Mexico 3.Plants and protists die and sink to the ocean floor. 4.Decomposition of biomass by bacteria on the ocean floor consumes oxygen dissolved in the water 5.Lack of mixing in water column maintains low oxygen levels near the ocean bottom Ag Drainage Water Management Webinar August 2011

Hypoxic Conditions in the Northern Gulf of Mexico – defined as a concentration of dissolved oxygen less than 2 mg/L In other oceans of the world, the upper limit for hypoxia may be as high as 3-5 mg/L (species and temperature affect range) hypoxia develops near the ocean floor (affects bottom dwellers – shrimp, oysters, bottom fish) Ag Drainage Water Management Webinar August 2011

Northern Gulf of Mexico (cont’d.): oxygen concentrations are stratified surface oxygen levels are typically >8 mg/L zone forms in spring; lasts until late Aug. or Sept. wind action by hurricanes (late summer) de- stratify the water column and return oxygen concentrations to normal Ag Drainage Water Management Webinar August 2011

Human Health Concerns: Excessive levels of nitrate in drinking water can cause human health problems. Short-term health effects: During digestion, nitrates transform to nitrites, which diminish the transfer of oxygen in the blood. Ag Drainage Water Management Webinar August 2011

Methemoglobinemia (blue baby syndrome) - a condition that results from high nitrites in the blood. This can be an acute condition in which health deteriorates rapidly over a period of days. Symptoms include shortness of breath and blueness of the skin. Results can be fatal Infants are particularly susceptible. Ag Drainage Water Management Webinar August 2011

Environmental and Ecological Concerns: Hypoxia and Low Dissolved Oxygen Effects – High aquatic species mortality Habitat loss Food chain alterations Loss of biodiversity Reproductive problems for fish Increased susceptibility to predation Ag Drainage Water Management Webinar August 2011

Table 1. Estimates of annual nitrogen inputs in metric tons to the Mississippi River basin and its major tributaries Source of Nitrogen Mississippi Basin above Missouri River All of Mississippi Basin Metric Tons Percent of Total Metric Tons Percent of Total Commercial fertilizer - all forms as N 1,898, ,873, Livestock manure 914, ,451, Legumes (soybeans and alfalfa) 375, ,031, Atmospheric wet deposition of nitrate as N 107, , Human domestic waste 188, , Industrial point sources 12, , Oxidized soil N ? ? Total 3,497, ,602, Source: Goolsby and Battaglin, and Hooper,USGS. "Sources and Transport of Nitrogen in the Mississippi River Basin.

Nitrogen inputs in 1991 Source: Buxton, USGS. Average stream yields

Ag Drainage Water Management Webinar August 2011

Ag Drainage Water Management Webinar To qualify for financial assistance on NM DWM required if land is drained, and DWM is feasible (feasibility based on slope, soil type, existence of pattern drainage, acres/economics) IWM is required if land is irrigated If both drained and irrigated, both of above required Nutrient Management Strategy and DWM ( National Bulletin: )

Next Presentation Hamid Farahani Ag Drainage Water Management Webinar August 2011