Water: Nonpoint Source Success Stories
Section 319 Success Stories, Vol. III: Missouri
Mississippi Delta Irrigation Water Management Project:
Irrigation Efficiency Improved
Bootheel Resource Conservation & Development Council, Inc.
18450 Ridgeview Lane
Dexter, MO 63841
Primary Sources of Pollution:
- agriculture (crop fields)
- poor irrigation efficiency
Primary NPS Pollutants:
- irrigation practices
- 20 percent to 50 percent water savings
- reduction in agricultural chemicals entering groundwater and surface water
The Mississippi Delta of Missouri encompasses about 4,000 square miles, or 2.5 million acres, of prime agricultural land. Forests and swamps originally covered this region, but it has become intensively developed for agricultural production.
The Mississippi Delta 319 Irrigation Water Management Project was implemented in 1995 with the goal of maintaining and enhancing Missouri's portion of the Mississippi Delta alluvial aquifer. The project area and demonstration activities occurred within the 700,000 acres of irrigated lands in the Delta. The management complexities of the intensively irrigated lands in the project emphasize the need in the region for comprehensive nutrient and pesticide management plans and maximum-efficiency water delivery systems.
Targeting irrigation system efficiency
The project involved field-scale demonstrations of three best management practices (BMPs) targeting the improvement of irrigation system efficiency:
- Side-inlet flood irrigation of rice, which allows water to be applied to each basin independent of the water levels in other basins. Water is delivered to each basin through a pipeline or an irrigation canal. The system can be set so that all basins fill at the same time.
- Surge-furrow irrigation for crops, which is used to improve the uniformity of water entering the soil down a row in a furrow irrigation system. Water is introduced to one area of the irrigated field for a certain duration, then switched to a different irrigated area, then returned to the original area. Surge valves automatically switch the irrigation water. Switching back and forth is continued until the entire length of the furrow is watered. By pulsing, or surging, the water advances down the furrow faster than it would with the constant flow in a conventional furrow irrigation system. By decreasing the time needed to advance to the end of the furrow, deep percolation is reduced. This is particularly true in coarse-textured soils.
- Furrow flow rate uniformity improvements for row crops, which will enable furrow irrigation systems using lay-flat irrigation tubing to apply water uniformly to individual furrows as needed. In this recently developed technology, a computer program calculates the needed gradient of the crown end of a field to match energy losses within the pipeline to equalize furrow flow streams. The program selects hole sizes to help make existing systems operate more efficiently. Uniform furrow flow streams result in water conservation (from 1 to 10 inches per acre per year), reduced potential of surface water contamination through reduced irrigation tail water (from 1 to 6 inches per acre per year), and increased yields. Roughly 200,000 acres could be furrow-irrigated each year using the lay-flat irrigation tubing system.
The three methods to be demonstrated were relatively unknown to Missouri farmers. The benefits of the side-inlet and surge-irrigation methods are well documented, and both methods are commonly used in other irrigated areas of the United States. The furrow flow uniformity improvement demonstration used technology recently developed in Missouri. It is especially important to southeast Missouri irrigators because it pertains to the use of lay-flat irrigation tubing. A higher percentage of southeast Missouri irrigators use lay-flat tubing than irrigators in any other irrigated area of the country.
Water savings and simpler management
For the eight side-inlet rice irrigation sites installed, the composite water savings consistently ranged from 30 percent to 50 percent on the fields. Another benefit of the side-inlet system expressed by producers was the simpler management. The producers believed that with side-inlet irrigation they experienced less wear on their levees, used fewer gates, did not have to adjust gates, and did not have to guess when to end their irrigation. Consequently, they had more time to take better care of their fields. Even without the water savings, producers felt the management aspect of the side inlet made it worthwhile to install.
For the six surge-valve/furrow-flow irrigation improvement sites, the surge systems averaged between 20 percent and 30 percent reduction in water use per irrigation, depending on soil type and system flow rate. The producers indicated they could also see a definite reduction in the pump times on their fields using the irrigation water management plans. In addition, they saw even application of water across their field as a benefit. In the case of soybeans, some farmers noted they did not see the damage that had previously occurred in oversaturated portions of their fields.
This project was also successful in transferring information after the completion of the demonstrations. At the time the project was proposed, there were few, if any, known producers in southeast Missouri using the side-inlet method of irrigating rice, as well as very limited use of surge/furrow-flow improvement systems. As of 2000 it is estimated that 20,000 to 30,000 acres of rice are being irrigated using the side-inlet method. Since the project's inception, an estimated 80,000 acres of irrigation water management have been put into practice, including 20,000 to 30,000 acres of surge irrigation. By comparison, in 1995 furrow flow improvement plans were used on fewer than 1,000 acres, surge irrigation plans were used on fewer than 100 acres, and there were no side-inlet rice irrigation plans.
These field-scale demonstrations were critical in establishing credibility among area producers and gaining their acceptance of the applicability of the BMPs. Equally important, the concentrated efforts of informing and educating producers about the successes of the project ensured continued use of these practices even after the project was completed.
Story 1 | Story 2 | State Water Quality Site
Upper Niangua Grazing Demonstration Project:
Counties Unite to Start Demonstration Farms
Southwest Missouri Resource Conservation & Development (RC&D)
283 U.S. Highway 60 West
Republic, MO 65738
Primary Sources of Pollution:
- agriculture (dairy/beef operations)
Primary NPS Pollutants:
- pasture management practices
- rotational grazing systems
- farmer education (workshops, manuals)
- average savings of $1/cow/day
- reduced labor
- less erosion and nutrient-contaminated runoff
The Upper Niangua watershed encompasses 217,000 acres in Webster, Dallas, and Laclede Counties in southwest Missouri. Dairy and beef operations, with an emphasis on forage production, constitute a large component of the agriculture in the watershed. Through support of section 319 funding obtained through Southwest Missouri Resource Conservation and Development (RC&D), seven landowners from these three counties implemented management-intensive grazing systems to better manage their cattle, manure, and pastures. The project was funded from March 1,1994, through December 31, 1999.
The objectives of the Upper Niangua Grazing Demonstration Project included the following:
- Demonstrate best management practices for pastures and use of animal waste to prevent nonpoint source pollution.
- Inform local and regional landowners of the economic and ecological benefits of proper pasture management.
- Demonstrate riparian corridor protection as a part of the total farm system.
Seven livestock/dairy operations were selected to participate as model sites to demonstrate the effectiveness of grazing best management practices. Each producer was required to implement a total resource management system, and incentive payments were provided for participation.
Splitting large fields into smaller fields (called paddocks) with electric fence allows for more efficient use of the pasture, healthier plants, and more plant diversity.
Management-intensive grazing systems were installed and customized to each producer's operation. Management-intensive grazing is a goal-driven approach to grazing management, characterized by balancing animal demand with forage supply through the grazing season and allocating available forage based on the animal's requirements. Underlying the approach is a basic understanding of how soil, water, plants, and animals interact with each other as influenced by climatic conditions and management decisions. The four goals used in implementing a management-intensive grazing plan for each participant included financial or economic considerations, environmental concerns, lifestyle, and production goals.
Workshops were held at these demonstration farms in the spring and fall to provide training to landowners and agency personnel working in the region. Highlighted were sessions on plant growth, plant management, soil fertility, species selection, livestock needs, water development, and other aspects of the management-intensive grazing system necessary to derive the economic and environmental benefits of participating. In addition, monthly Pasture Walks proved to the "Show Me" Missouri farmers the value of these systems.
The University of Missouri Extension Service also published a valuable manual for dairy farmers called the Missouri Grazing Dairy Manual. The manual covers all aspects of pasture-based dairying in Missouri, including managing nutrients from manure and inorganic sources in pastures. The manual documents how the amount of phosphorus added to a stream when a cow defecates directly into it—just once—can be the same as the amount of phosphorus that runs off an acre of pasture in a single rain runoff event.
The final chapter in the manual highlights the economics of the pasture-based dairy. Missouri is fortunate to have at least 8 months during which pastures can be grazed. The diversification of pasture species that results from rotational grazing provides high-quality forage throughout that long grazing season. High-quality forages mean greater milk production, which in turn provides greater returns to the producer.
Water in every paddock allows for better manure distribution and nutrient recycling, reduces stress on animals, and reduces erosion.
Results of pasture management
The producers in this project saved an average of $1 per cow per day by using pasture management practices. They also decreased labor because of the reduced time needed for harvesting forages and handling waste. This was evident to the landowners from Dallas County. The landowners with the management-intensive grazing systems were able to extend their grazing season and wait up to 2 months longer before feeding supplemental hay than some of their neighbors during an extensive period of drought.
Through this demonstration project, managed grazing strategies and riparian corridor protection reduced the quantity and improved the quality of the farmland runoff. As noted in the dairy manual, dairy cows excrete 70 percent of the nitrogen, 60 percent of the phosphorus, and 80 percent of the potassium they consume in their diets. In grazing systems, the nutrients that have been consumed are returned to the pasture through manure and then taken up again by the forage. This cycling of nutrients leads to a lower runoff of nutrients from pasture systems because fewer nutrients are imported to the pasture by heavy concentrate, or hay feeding. A greater number of rotations in a grazing system provides for more evenly distributed manure, so nutrients are not concentrated in only a few spots.
The demonstration project protected ground cover and provided more efficient forage production. The manual provided information showing that forages managed in grazing dairy systems in Missouri were of very high quality, with an average crude protein content of 21 percent from April through December. These forages also furnish vigorous ground cover, which helps reduce erosion and runoff compared to conventionally grazed pastures. Legume growth and reseeding are enhanced because of longer recovery periods for pastures in a rotation. The legumes can "fix" nitrogen in the soil so that less nitrogen needs to be applied to pastures. Water infiltration is increased because of improved soil structure, which reduces runoff. In addition, the extensive root system of healthy forages decreases the potential for leaching by trapping particles and by taking up water.
The Upper Niangua Grazing Demonstration was a success. This demonstration project had numerous partners: funding was provided by an Environmental Protection Agency grant through the Missouri Department of Natural Resources; the U.S. Department of Agriculture's Natural Resources Conservation Service, University of Missouri Outreach and Extension, Dallas County Soil and Water Conservation District (SWCD), Laclede SWCD, Webster SWCD, and Missouri Department of Conservation provided technical assistance.
The ongoing impact of the project in this Ozark region of Missouri, known for its clear lakes and streams, will be felt by all those who enjoy this area—visitors and residents alike.
|Recipe for Success in Missouri
|Cattle||Match to forages|
|Fencing||Enough to split each farm into eight or more paddocks|
|Watering pipe||Enough to carry water to all paddocks|
|Watering troughs||Enough to supply cool, clean water to cattle in each paddock|
|Forages||Large variety of dense, palatable, high-quality grasses & legumes|
|Manure||Distributed evenly in all paddocks|
|Landowners||Seven progressive, open-minded farmers|
Carefully split each farm into paddocks (pasture subdivisions) with the fencing. Insert watering troughs into each paddock, and connect them with pipeline. Keep cattle on one paddock at a time, rotating based on forage growth and availability. The variety of forages will increase the longer you cook this mixture. Let it rain on the mixture to moisten evenly. Ask the seven farmers to open the meal to anyone interested and share at "Pasture Walk" gatherings and workshops.
Delicious! (And guess what? Everyone wants the recipe!)