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Guarding the Wet Stuff

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Evolving Best Management Practices are helping farmers and other Oregonians preserve our water.

For years the symbol of the Natural Resource Conservation Service, called the Soil Conservation Service until a recent name change, has been a giant blue raindrop with a green line under it and a brown line under the green line. To Dan McGrath, a vegetable crops agent in the OSU Extension Service's Marion County office, the logo embodies what must be done to protect water quality in Oregon and elsewhere in the United States: "putting a green barrier between rain drops and soil. What we are seeing is the strong relationship between soil conservation and water quality. Simple practices of soil conservation protect water quality."

That line of reasoning has guided federal policy on soil conservation since the Soil Conservation Service was created in the 1930s as a way to end the Dust Bowl. But in Oregon, just as in many other states, more emphasis has been put on the soil conservation part than the water quality part. Until recently, that is.

It isn't that the quality of Oregon's water is bad. Beyond some trouble spots, the state's water generally is good. But many Oregonians have realized that steps must be taken to keep it that way. In agriculture, for example, key goals have been to reduce non-point pollution without adverse impacts on productivity and income. And in the last five years, tools that help farmers do that have emerged from a collaborative effort by Oregon State University, the U.S. Environmental Protection Agency, the Natural Resource Conservation Service, the state Department of Environmental Quality, many other public agencies and, perhaps most importantly, farmers. These tools are called Best Management Practices (BMPs).

Farmers are interested in how they can enhance environmental quality while maintaining their productivity and income without regulatory pressure. Best Management Practices are a series of voluntary guidelines that encompass the best ways to deal with problems in agriculture, forestry and other natural resource-related activities. Research by OSU Agricultural Experiment Station scientists on campus and at several branch stations is developing and refining BMPs. Campus extension specialists and county extension agents transfer the practices to farmers and other land managers so they can fit them into their day-to-day operations. In recent years, these practices have dealt increasingly with water quality.

"Federal regulations grew in the 1960s to deal with point sources of pollution-sewage plants, industrial wastes from meat packing plants, pulp mills," says Ron Miner, an extension specialist in OSU's Department of Bioresource Engineering. "Money was invested in the 1960s, 1970s and 1980s to improve these conditions. Once these sources of pollution were under control, it became obvious that such regulations alone wouldn't restore all water quality. This caused a shift of attention to non-point sources."

Non-point sources of pollution include hundreds of other ways water can be contaminated from less concentrated sources. These range from things such as runoff into streams of chemicals from city parking lots, home lawns and cropland, to infiltration into groundwater of substances such as fertilizer, herbicides and natural organic materials in the soil.

A man crouching on a log near a river.

Derek Godwin, an OSU Extension Service coastal watershed specialist in Curry County, checks a log weir placed in a stream on the Lyle Dishner ranch near Gold Beach. The weir stabilizes the stream bed and creates a pool that improves spawning habitat for salmon. Photo: Bob Rost

"Most of these non-point sources of pollution have to do with rainfall-driven sources," continues Miner. "For example, with a field next to a stream, the erosion into the stream is a non-point source. If you have 30 cattle grazing above a stream, there's a potential pollution source. But how those cattle are managed determines the impact."

Federal regulations require states to control non-point sources of pollution. Because of this, cities with a population above 50,000 are required to treat runoff from rain. But often individual landowners and property owners are the sources of problems. "To reduce pollution, these individuals would have to change the way they did business," says Miner. "This is difficult to monitor and police, especially if the pollution occurs at the time of rainfall. The way to do a lot of it was by education and by the use of different management practices. Hence you have the concept of Best Management Practices."

"Many of these techniques are nothing new. Farmers developed them originally, long ago," say Miner. "In many cases, Best Management Practices are more a case of identifying and integrating techniques."

He says reaction from the people directly affected has generally been good. "I doubt we will ever get total compliance," he says, "but that doesn't mean we can't work on it. Even with all the attention to non-point pollution in recent years, there are still 870 streams in Oregon not meeting water quality standards. This indicates the magnitude of the challenge."

Oregon's varied climates, soils and crops have led to an equally varied series of solutions to its water problems. In some instances, Best Management Practices were the key factor in alleviating problems. In others, they played a less important role.

Although they are not the only solution to water problems, BMPs are protecting and improving water quality in Oregon. A look at some crops in some regions of the state reveal examples of the benefits that are resulting from their use.

Vegetable Crops, Willamette Valley

"There are primarily two types of water pollution," says Dan McGrath in Marion County, "nutrients entering the groundwater, and pesticides, usually herbicides, clinging to clay and organic matter of the soil that bind to surface water in runoff. It is not realistic to think we can eliminate all nutrient leaching from a farm. It is more practical to try to limit it so it does not get into groundwater and cause health problems. That we can do."

A man standing in a cauliflower field.

Marion County extension agent Dan McGrath examines a cover crop of common vetch interplanted in a field of cauliflower on the farm of Larry and Ron Pearmine near Keizer, Oregon. The cover crop controls winter soil runoff, protecting water quality. Photo: Bob Rost

The sizable increase in the winter cover crop in the Willamette Valley in the last 10 years has been driven by water quality concerns. McGrath says that planting cover crops-grasses planted after harvest and plowed under in the spring-recaptures leftover nitrogen and keeps it from leaching into the groundwater. It isn't possible to put cover crops on all row crop ground because they leave the ground too wet in the spring. Early snap bean plantings, for example, need to be planted in dry ground, according to McGrath.

Pesticides present another kind of problem, according to McGrath. Because they cling to small particles of soil, especially in clay, they find their way easily into streams and rivers via muddy water after rain or irrigation--if they aren't stopped. Here is where old-fashioned soil conservation practices come into use.

"Farmers, like most people, want clean water," he says. "There are practical strategies for coming up with it. The critical issue is how to maintain productivity while protecting the environment."

John Luna, an OSU horticulture professor, worked with McGrath to develop and demonstrate integrated cover crop management systems that would help western Oregon vegetable producers reduce nitrate contamination of groundwater. Twenty-one growers participated in the program beginning in 1992, evaluating 30 cereal and legume crops. All of the cereal crops dramatically reduced soil nitrate leaching, according to Luna. Legumes did not provide adequate soil nitrate scavenging during the winter, but produced the most available nitrogen for the following year's vegetable crops.

A man on a tractor, creating rows in a field.

OSU Agricultural Experiment Station horticulture researcher John Luna plants cover crops on a research farm. Luna is helping western Oregon vegetable growers identify cover crops such as wheat and legumes that prevent nitrates from leaching into groundwater. Photo: Bob Rost

Preliminary findings indicate that a mixture of cereals and legumes planted in the fall can significantly reduce leaching of soil nitrate into the groundwater during the rainy season. These cover crops, when managed correctly, can reduce nitrogen fertilizer requirements. Also, these crops dramatically reduce soil erosion and the loss of agricultural chemicals through surface water runoff, according to Luna.

Vegetable Crops, Treasure Valley

The problems are much the same in the Treasure Valley, which straddles the Oregon-Idaho border around Ontario, Oregon. The valley was developed more than 100 years ago as a surface irrigation area. When water soaks into the soil it carries nitrates into the groundwater. Beginning in 1990, a coalition of farmers, agency employees, representatives from the commodity commissions, extension agents and scientists from OSU's Malheur Agricultural Experiment Station at Ontario began to look at the problem of groundwater contamination from nitrates.

"Our basic philosophy was that the world is a complex place--every field is different with its own crop history, soil, the way it lays," says Clint Shock, superintendent of the Malheur experiment station. "It is very difficult to make formulas and prescribe rules and laws everyone has to follow. The reality of the crop system is too complex for that."

Instead, the coalition developed workable BMPs to help alleviate the problem. These ranged from publishing a guide to efficient irrigation scheduling to promoting drip irrigation (where scarce water comes out in precise drips rather than in a flood that causes excessive runoff). Results so far have been promising, according to Shock. "The average of nitrates in wells we are monitoring is going down," he says. "Fertilizer use is better and water use improved."

Wheat, Columbia Basin

Two years ago, Don Wysocki, an OSU extension specialist at the Columbia Basin Agricultural Research Center in Pendleton, joined with other extension specialists from wheat-growing areas around the country to write a manual for the National Association of Wheat Growers. The manual presented suggestions for improving the quality of both surface water and groundwater.

A man in a wheat field using a large drill to collect soil samples.

Don Wysocki, an extension specialist at the Columbia Basin Agricultural Research Center near Pendleton, drills soil samples from a wheat tillage test plot. Such on-farm research, done with growers, helps scientists evaluate management practices in realistic settings. Photo: Bob Rost

"A grower can go through this manual, initiate a practice and determine the impact on water quality," says Wysocki. "The intent here was for the growers to become pro-active. We were trying to be preemptive to regulation, to let the industry be ahead of the curve before there was legislative action or regulation dealing with water quality."

Ninety percent of Oregon's wheat is grown in dryland conditions because rainfall is limited each year and groundwater is too deep to reach. This meant that not all of the manual applied to conditions in the West, because in the other major wheat-growing area, the Midwest, heavy summer storms drench fields regularly. Despite this limitation, the manual has been well received and helpful, according to Wysocki. "What we wanted to do here is to look at the farm as an integrated system, with biological, economical and sociological components. Because of this, you have to develop BMPs that integrate water quality concerns into this system.

"Since the 1985 farm bill, any land with a highly erodible designation--that's one half of dryland farms in Oregon--has to have an approved conservation plan," notes Wysocki. "These plans address erosion. However, if you can control erosion you can control a big threat to water quality."

"In general, about half of wheat land [in the Columbia Basin in Oregon] is fallow-a crop planted every other year," adds Wysocki. "If we can come up with alternative crops like canola we would have less fallow land and, thus, less land that's unprotected from erosion," he says.

Pear Crop, Southern Oregon

Similar concerns in the fruit-growing areas of Southern Oregon have propelled research into surface and groundwater quality problems.

One study by Richard J. Roseberg, assistant professor of crop and soil science at the station, is for the U.S. Bureau of Reclamation. "We are working to improve the water supply model," he says, "to determine when to supply water to a farm at the correct time and how effectively to move water from point A to point B. You also need weather forecast information. You can cut down on wasted water if you know it is going to rain. Or, if it's going to be dry, you need to know that you have to move water."

In a second part of this study, researchers are monitoring soil moisture twice a week to see how much water plants require. The results have shown that growers could reduce water usage by up to 17 percent and not hurt crop growth, according to Roseberg. "Although this does not have a direct impact on water quality, if you apply less water, there is less potential for runoff into streams," he says.

Another study Roseberg is working on, in cooperation with OSU bioresource engineer John Selker, involves the use of underground water sampling devices. The goal is for irrigation practices to provide enough water for crops but not so much that there is runoff.

Soil in one region of the Rogue Valley is 70 percent clay, something pears alone among fruit trees can tolerate. "When these soils dry out, they crack," says Roseberg. "This creates a pathway because the water shoots down the cracks. Whatever is in there goes in the groundwater." Four different irrigation systems are being used for the tests: flooding (where water is applied uncontrolled), over-tree sprinklers, micro sprinklers (a drip line system with a spinner to move the water) and a pulsater system (a small bladder-like container attached to a sprinkler that releases water in pulses). "The whole point is to modify irrigation to match the soil type to avoid surface runoff and prevent flow through cracks," Roseberg says.

Dairy Farms, Willamette Valley

With dairy farmers all over the Willamette Valley and the Oregon Coast, contamination of groundwater comes from another kind of natural source-cows. Neil Rambo, an extension agent in Washington County, has been working with the Natural Resources Conservation Service and the Farm Service Agency to provide farmers with information and education so they can control their animal wastes and prevent them from contaminating ground and surface water. This has ranged from setting up a system to catch manure-mixed water as it washes out of milking parlors, to installing rain gutters on barns so that rainwater will not mix with whatever manure might be on the ground.

Two researchers speaking to each other with a penned cow behind them.

Washington County extension agent Neil Rambo, left, discusses manure management with Forest Grove-area dairy farmer Pete Jansen. When the time is right to avoid runoff, Jansen uses manure stored in a huge tank to fertilze pasture land. Photo: Bob Rost

The most ambitious approach involves building manure storage facilities. These range from lagoons and moveable tanks that allows farmers to take liquefied manure into fields and spray it on crops, to a more simple storage facility where a scraper pushes the manure to a point where it can be collected and moved to the fields. "The big problem is economic," he says. "We need to find what the farmers can afford. There has to be some method of storing the manure for as long as six months, then some means of getting it on the ground come springtime."

According to soil scientist John Hart, OSU researchers and extension specialists have developed fertilizer guides that show farmers how much natural fertilizer is needed to equal commercial grades, and test kits they can use to determine soil fertilizer needs.

Fish Habitat, Curry County

Derek Godwin, a watershed management extension agent in Curry County in Southern Oregon, is working with watershed councils in the area, helping them use BMPs to improve fish habitat and water quality. "Down here it's a fish enhancement thing," says Godwin. "Most water quality problems here are related to fish habitat."

The organization of the watershed councils around Oregon grew out of a $10 million grant by the 1993 legislature to set up the councils--comprised of both agriculture and timber landowners, city and county officials, real estate interests, government agencies and others--to do fish enhancement and water quality improvement work. Godwin works with all of the councils in his area.

A picturesque mountain stream.

Opal Creek, a pristine stream east of Salem, Oregon. Photo: Tom Gentle

"So far the results have been fantastic," he says. "The big thing here is that it is all voluntary. We provide information for them. They decide what projects to do." Many farmers have concentrated on restoring salmon to their streams. In this regard, many have replaced culverts that allow fish passage, built fences and off-stream watering areas to reduce livestock impacts in the riparian area, and also planted trees in the riparian area. Riparian areas are narrow strips of land that border creeks, rivers or other bodies of water. Although they occupy only a small percentage of a watershed, they are important because they cool water temperatures and aid in sediment filtering, bank stabilization and water storage and release. A healthy, functioning riparian area also aids fish and wildlife habitat.

For Godwin, as well as other specialists trying to improve the quality of Oregon's water, Best Management Practices are most effective if prepared carefully and applied in a calm, non-dictatorial way. "A lot of non-point pollution problems, just like changes in weather and too much rain, are hard to regulate," he says. "Just because a BMP has been written and the Oregon Department of Environmental Quality says you follow it doesn't mean the pollution problem will be solved. It is a practice aimed to solve a problem."

Adds Marion County extension agent Dan McGrath: "BMPs are not the total answer. They are a start. Suggesting that BMPs be codified into law does not honor farmers as stewards of the land. Farmers care about the environment like we all do. We must honor their decision-making capability and their integrity, and we must all focus on making the water that leaves ag fields crystal clear. We're up to the challenge."

Published in: Water