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Water availability and water quality issues have become predominant public environmental concerns during the last decade. Groundwater in many areas has become contaminated by nitrate and pesticide residues. Surface water quality is compromised for other beneficial uses. Growers and ranchers are often blamed for water problems. A fairer and more creative approach is to consider all possible options to simultaneously improve practices and profitability, so that each water issue is not considered a zero sum game --- for the environment to win, agriculture does not have to lose water or freedom of action. The irrigation industry, growers, research, and extension need to pursue "win-win" options where the economic interests of agriculture are protected, product yield and quality are enhanced, and water resources are protected.
Water use, water resource conservation, and water quality are key factors in the economy and quality of life in Malheur County. Water is both the largest input into our agriculture and very scarce. Water quality is affected by range and agricultural practices. Both water availability and quality affect the success of farms, prosperity of urban areas, and survival of native species. Water use and conservation must be examined from a watershed perspective and with approaches that are inclusive of environmental and economic goals. These efforts place a premium on communication skills, and the need to value others.
A decade ago, the areas of irrigated agriculture of Malheur County were faced with groundwater contamination by nitrate and residue of the herbicide Dacthal. Growers, growers' associations, and agencies have cooperated to creatively solve problems. Agencies divided the roles of research, education, implementation, and funding to pursue long term environmental goals to clean up groundwater while respecting economic constraints faced by producers.
The Malheur-Owyhee watershed in southeastern Oregon contains millions of acres of sage brush steppe used principally for extensive grazing and secondarily for recreation, relatively small areas of forest, and 250,000 acres of irrigated crops in Malheur County. Malheur County is Oregon's southeastern corner. Both the Malheur River and Owyhee River, tributaries of the Snake River, drain the area. The largest city, Ontario, is only 56 miles from Boise, Idaho, but 377 miles from Portland, Oregon. There are only 28,500 inhabitants in this arid county, mostly concentrated in the towns of Ontario, Nyssa, and Vale situated in areas of intensive agriculture. Rainfall is far less than crop water needs, averaging only 10 inches per year at the lower elevation sites, with frequent occurrence of drought. Rainfall is distributed mostly in the non-growing season. The county covers 6,352,620 acres, of which 94% is rangeland and 4 % is irrigated land. Agriculture in Malheur County consists of developed intensive crop production and extensive cattle operations.
Irrigation water comes largely from snow melt and runoff from rangelands. Reservoirs capture the seasonal runoff at elevations higher than the crop land. Water flows via canal systems to farms by gravity. The region was developed predominantly as a furrow irrigation system prior to 1940. Reservoirs, canals, and water delivery are managed by the Owyhee Irrigation District, Vale Oregon Irrigation District, Warm Springs Irrigation District, the Owyhee Ditch Company, and twelve smaller irrigation districts.
Crop rotations and land tenure have been sound. Family farms predominate and use crop rotations that include onions (Allium cepa), sugar beets (Beta vulgaris), wheat (Triticum aestivum), corn (Zea mays), beans (Phaseolus vulgaris), potatoes (Solanum tuberosum), alfalfa (Medicago sativa), alfalfa grown for seed, spearmint (Mentha spicata), peppermint (Mentha piperita), and other crops. Land has mostly been owned by owner-operators, with a tendency toward consolidation into larger units during the last decade.
The sustainability of intensive agricultural crop production in southeastern Oregon is challenged by soil loss, groundwater contamination, and surface water quality problems. Practices are in transition towards reductions in irrigation-induced erosion and reductions in groundwater contamination from herbicides and fertilizers. Intensive agricultural systems are changing from a period of very liberal use of nutrients and irrigation water per acre toward more precise applications of nutrient and water resources which more closely match crop needs.
Nitrogen chemical fertilizer inputs historically have been considerably
greater than crop N removal (Shock and Stieber, 1991). Following World
War II nitrogen fertilizers were relatively inexpensive, and became widely
used. Nitrogen fertilizer rates were based on assurance of maximum yield,
rather than minimum rates and techniques to make N inputs most effective.
All chemical N forms such as ammonia, ammonium, and urea are subject to
oxidation to nitrate, which can be leached to groundwater. Relatively high
N inputs combined with furrow irrigation lead to significant risk of nitrate
leaching. The predominance of furrow irrigation facilitates deep leaching
and the movement of nitrate to groundwater. Groundwater became contaminated
with nitrate and residues of DCPA (dimethyl 2,3,5,6-tetrachloro-1,4-benzenedicarboxylate,
sold as Dacthal) (Bruch, 1986). DCPA, a grass
herbicide, degrades to a stable di-acid residue which is also soluble and
mobile in the soil solution. Northeastern Malheur County was designated
Oregon's first Groundwater Management Area (Fig. 1) by ODEQ in 1989 due
to nitrate-N and the di-acid breakdown product from DCPA in the groundwater
(Anon. A., 1991).
Community members realized in 1989 that environmental remediation would be difficult. By the time that the groundwater management area was established, substantial nitrate and DCPA residues were also present in the vadose zone, the unsaturated layer between the crop root zone and groundwater. Aquifer movement to the Snake, Malheur and Owyhee Rivers is slow and delays dilution and remediation (Gannett, 1990). In summary, immediate reductions in groundwater contamination faced hurdles that included 1). the use of furrow irrigation systems that promote leaching, 2). fertilization and irrigation technology based primarily on the assurance of yields, 3). vadose zone contamination, and 4). aquifer hydrology that both moved slowly and was principally supplied by deep leaching from intensive agricultural operations.
The Governor appointed a citizens Northern Malheur County Groundwater Management Committee and a complementary Technical Advisory Committee in the fall of 1989. Technical advice and support to the citizen's committee came from the SWCD, NRCS, Malheur Farm Service Agency Committee of the USDA (FSA), Malheur County Cooperative Extension of Oregon State University (OSU), Malheur Experiment Station of OSU (MES), Malheur County Health Department, and the Owyhee Irrigation District. The citizens committee cooperated with the Oregon Department of Environmental Quality (ODEQ) to write the Northeastern Malheur County Groundwater Management Plan and implement it starting in the fall of 1991. Both the technical and citizens' committee embraced environmental goals, the value of producers, and a cooperative voluntary approach. Writing and adoption of the plan was difficult, since several versions of the draft plan did not allow the option of responsible voluntary action.
In implementation, local agency personnel accepted responsibility and coordinated the development of creative research, demonstration of useful practices, and implementation of practices as documented in the annual reports and HUA reports of the SWCD. From 1990 through 1999 new practice options were tested at MES to reduce N fertilizer use, DCPA use, reduce sediment loss, and improve irrigation efficiency and were published in the annual reports of the station. Work proceeded from relatively small plots on the experiment station to large strips through growers' fields, and eventually to large scale implementation. Research proposals were reviewed, improved, and funded by the Oregon Potato Commission, the Nyssa-Nampa Sugar Beet Growers Association, the Idaho-Eastern Oregon Onion Committee, the Oregon Wheat Commission, as well as the ODEQ, Oregon Department of Agriculture, Oregon Department of Economic Development, US Environmental Protection Agency, NRCS and STEEP for a total of $ 1,041,699 for the decade. Education and demonstration occurred largely through the SWCD and OSU extension. Implementation of new practices was facilitated by FSA which cost shared 50 % of the cost of new practices for irrigation management, erosion control, nutrient management, and weed control. From 1993 to 1998 new practices were demonstrated on 2634 hectares per year with corresponding FSA federal cost shares averaging $179,314 per year.
Research, demonstration, and implementation projects covered the following:
1). evaluation of the irrigation management of potatoes, onions, and hybrid poplar trees (Populus deltoides x P. niger),
2). comparison of irrigation systems for the production of onions and potatoes,
3). irrigation practices to reduce sedimentation from irrigation induced erosion, and
4). re-examination of the N requirements of potatoes, onions, sugar beets, and wheat,
5). use of sugar beets and wheat to remove nitrate following shallow rooted crops,
6). alternatives for DCPA and DCPA banding vs Broadcast applications,
7). alternatives for useful recycling of waste streams from agricultural productions and processing. Examples of innovation and change for irrigation management are highlighted below.
Crop irrigation criteria were re-examined through replicated field trials repeated over several years. Irrigation criteria were needed to assure yield without irrigating too frequently. Threshold levels of soil water potential for the onset of irrigation were determined for potatoes (Eldredge et al., 1996 and 1992), onions (Shock et al., 1998a), and poplar trees (Shock, et al., 1999a). The Malheur County Cooperative Extension and SWCD helped growers apply the irrigation criteria to their fields through a daily soil moisture monitoring programs. Daily estimates of crop evapotranspiration were started in 1992 by the use of an AgriMet weather station at MES in cooperation with the USDA Bureau of Reclamation. Growers with drip or sprinkler irrigation systems could begin to carefully match water applications with crop water use.
Irrigation management of potatoes illustrates the environmental and economic benefits achievable through carefully matching water applications to crop water needs. Irrigation of potato at -50 to -60 kPa on Malheur County silt loams optimizes potato yield, grade, and internal quality (Eldredge et al., 1996 and 1992). Yet, the failure to fully meet the crop's evapotranspiration requirement results in severe loss of yield and economic return (Shock et al., 1998b). Furthermore, with irrigation applications matched to crop water needs, N fertilizer requirements are lower in Malheur County than the levels that are generally recommended (Feibert et al., 1998). Potato growers use careful irrigation scheduling with soil water potential monitoring on over 100 commercial fields.
For fields that are difficult to irrigate with furrow irrigation, drip-irrigated onions proved to be more productive than furrow or sprinkler-irrigated onions (Feibert et al., 1995). In this arid environment, drip irrigation has the potential to supply water closely matched with the crop water needs, resulting in highly productive crops with minimal nitrate leaching risk. With precise irrigation scheduling where drip irrigation is being used, it may be feasible to reduce N fertilizer inputs.
Progress in reducing irrigation induced erosion has come through adoption of polyacrylamide (Shock and Shock, 1997), furrow mulching (Shock et al., 1997), sediment ponds, filter strips, laser leveling furrow-irrigated fields, and alternative irrigation systems. Control of irrigation-induced erosion with straw mulch proved to increase the yield and quality of onions (Shock, et al. 1999b).
Technological transfer has been promoted through over 100 meetings including field days at research plots, field tours of growers' fields, workshops, and presentations to grower association regular annual meetings. Results have been distributed in extension and SWCD news letters, newspaper and trade journal articles, radio shows, widely distributed videos, and scientific journals. As growers realize that the implementation of new technology will not only help alleviate environmental problems, but also be cost effective, the technology has spread into a widening circle of growers. Chemical applicators incorporate refined procedures into their routines.
Malheur County's highly active participatory program has resulted in downward trends in DCPA residues and an overall downward trend in groundwater nitrate. Progress has come about through wide cooperation. Necessary elements have included interagency cooperation, grower involvement in plans and ideas before research was conducted, creative research, effective extension and education, and volunteer implementation. The program has increased public consciousness of the environmental effects of farm operations.
Surface water quality: Stream segments have been listed by ODEQ as being water quality limited due to temperature, toxic chemicals (mercury, and remnant traces of dieldrin (diethyl,2,2'-dihydroxyamine), and DDT (dichlorodiphenyltrichloroethane)), fecal coliform bacteria, other bacteria, chlorophyll a, and stream flow modification. Sedimentation, nutrient loading, and eutrophication are additional parameters of concern. Water quality standards in the Malheur-Owyhee Watershed need to be re-evaluated so that they are based on the site potentials in this ecological region and natural background levels of mercury and phosphates.
Endangered Species: Human land use interacts with plant and animal communities influencing the survival of several species, including sage grouse, red band trout, and bull trout.
There are continual needs for those engaged in the use and management of natural resources in the public and private sectors to respect and value each other and value economic as well as environmental goals. Each economic and environmental problem evades simplistic answers, yet cooperative progress over the past decade sets a positive precedent for future solutions. Environmental progress in Malheur County has been possible through cooperative action of citizen's committees such as the Citizen's Groundwater Advisory Committee begun in 1989 and currently the Malheur Owyhee Watershed Council. These groups have drafted broad goals which include environmental goals, key community economic interests, and ways of organizing themselves. Representatives of SWCD, NRCS, OSU extension, OSU research, ODEQ, Irrigation districts, BLM, ODFW, and others participate as advisors. Research and education have been key components of Malheur County's efforts. Successful implementation of improved practices has been greatly enhanced by SWCD, FSA, and NRCS programs.
The approach of the past decade, with it emphasis upon cooperation and voluntary responsible action, is being replaced by many faceted threats based on administrative rules. Loss of grazing rights or water use rights are threatened due to violation of numerous rules and regulations, already written or yet to be composed. Reasonability, economic feasibility, or economic impact seem to weigh little in present considerations. Is there some way that we can obtain a clearer, higher vision of what direction we need to go to reestablish a cooperative approach.
There are continual needs for those engaged in the use and management of natural resources in the public and private sectors to respect and value each other and value economic as well as environmental goals. Each economic and environmental problem evades simplistic answers, yet cooperative progress over the past decade sets a positive precedent for future solutions.
Progress has not been confined to environmental priorities mandated by state agencies. Reduction in sediment losses and nutrient losses from agricultural land and recycling of agricultural wastes have occurred based on local initiatives. Progress in reducing irrigation induced erosion has come through testing of many practices and adoption of polyacrylamide, furrow mulching, sediment ponds, filter strips, laser leveling furrow-irrigated fields, and alternative irrigation systems.
Over the past decade, substantial progress has been made in developing and adopting cultural practices including better N fertilizer timing and rates, soil and tissue sampling, use of sugar beets and wheat in rotation following onions and potatoes to recover residual soil nitrate and mineralized nitrogen, adoption of many improved irrigation management techniques, adoption of drip irrigation systems, and the replacement of Dacthal herbicide. Groundwater quality is improving.
Major agricultural organic wastes in Malheur County include wheat stubble and animal manure generated directly by agricultural production, onion culls from fresh onion packing sheds, sugar beet pulp from sugar processing, sludges from processing potatoes and onion oil, seed screenings from alfalfa seed cleaning operations, and spent compost from growing mushrooms. Alfalfa seed screenings are now used for mushroom compost, which itself is recycled as a soil amendment. Progress is being made on the use of sludges for fertilization. Recycling organic wastes has improved.
If unneeded shortcuts are taken in the path to environmental improvement by disregarding the input of producers and local citizens, much could be lost in developing an ethic of stewardship.
The emphasis on positive cooperation could be adapted to the wider context of environmental and economic issues throughout the watershed. For a cooperative approach to flourish, assessments of environmental risk need to be sound, reasonable goals need to be adopted by the community, and wide ranges of options to attain those goals need to be considered. Practices will be adopted that will be environmentally beneficial and yet economically effective for producers.
Cooperative efforts already underway to improve surface and groundwater quality need to continue. Opportunities exist to develop new applications through research and to extend adopted practices to additional growers through education and incentives.
Bruch, G. 1986. Pesticide and nitrate contamination of ground water near Ontario, Oregon. Impacts on Groundwater Conference, Proc. Am. Water Well Assn. 11-13 Aug. 1986. Omaha, NE.
Eldredge, E. P., Z. A. Holmes, A. R. Mosley, C. C. Shock, and T. D. Stieber. 1996. Effects of transitory water stress on potato tuber stem-end reducing sugar and fry color. Am Potato J. 73:517-530.
Eldredge, E.P., C.C. Shock, and T.D. Stieber. 1992. Plot sprinklers for irrigation research. Agron. J. 84:1081-1984.
Feibert, E. B. G., C. C. Shock and L. D. Saunders. 1998. Nitrogen fertilizer requirements of potatoes using carefully scheduled sprinkler irrigation. HortSci. 32:262-265.
Feibert, E.B.G., C. Shock, and M. Saunders. 1995. A comparison of sprinkler, subsurface drip, and furrow irrigation of onions.Oregon State University Agricultural Experiment Station, Special Report 947. pp 59-67.
Gannett, M.W. 1990. Hydrogeology of the Ontario Area Malheur County, Oregon. State of Oregon Water Resources Department, Groundwater Report No. 34, 44p.
Shock, C. C., E. B. G. Feibert, and L. D. Saunders. 1999a. Irrigation Management for hybrid poplar production, 1997-1998. Oregon State University Agricultural Experiment Station, Special Report 1005. pp. 90-103.
Shock, C.C., L.B. Jensen, J.H. Hobson, M. Seddigh, B.M. Shock, L.D. Saunders, and T.D. Stieber. 1999b. Improving onion yield and market grade by mechanical straw application to irrigation furrows. HortTech. 9:251-253.
Shock, C. C., E. B. G. Feibert, and L. D. Saunders. 1998a. Onion yield and quality affected by soil water potential as irrigation threshold. HortSci. 33:1188-1191.
Shock, C. C., E. B. G. Feibert, and L. D. Saunders. 1998b. Potato yield and quality response to deficit irrigation. HortSci. 33:655-659.
Shock, C.C., J.H. Hobson, M. Seddigh, B. M. Shock, T. D. Stieber, and L. D. Saunders. 1997. Mechanical straw mulching of irrigation furrows: soil erosion and nutrient losses. Agron. J. 89:887-893.
Shock, C.C. and B.M. Shock. 1997. Comparative effectiveness of polyacrylamide and straw mulch to control erosion and enhance water infiltration. In Wallace, A. Handbook Of Soil Conditioners. Marcel Dekker, Inc. New York, NY. pp. 429-444.
Shock, C.C. and T.D. Stieber. 1991. Nitrogen uptake and removal by selected crops. Oregon State University Agricultural Experiment Station, Special Report 882, pp. 182-186.
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