SAFE WATER FOR YOUR
Water is never just pure hydrogen and oxygen (H20), because water dissolves minerals and organic compounds as it moves through the air and soil. Unacceptable materials, including bacteria from animal and human waste, synthetic chemicals such as gasoline and industrial solvents, or naturally occurring nitrate and salt, may find their way into water.
Here are the possible drinking water contaminants you should be concerned about:
The best way to determine the quality of your drinking water is to have
it tested. Most water appears clean and problem-free at the tap, but it
may not be as safe or acceptable for household activities as you would
like. Annual testing by your local health department or by an
independent laboratory will indicate possible problems.
FROM THE EDITOR
The Institute of Southern Studies, a public interest advocacy research group in Durham, North Carolina, recently ranked Idaho's environmental health as 19th among the 50 states. The research group judged 256 factors related to the environment and public health. Oregon and Washington ranked 1st and 9th, respectively.
The Institute of Southern Studies found that Idaho had the cleanest water in the nation and ranked second in handling its forest and fishery resources. On the down side Idaho was ranked 45th in control of agricultural pollution (primarily for poor erosion control and lack of implementation of conservation practices compared to other states). Idaho also received low marks in per capita water use and recycling programs. Incidentally, Idaho's congressional delegation was ranked 47 out of 50 by the League of Conservation Voters.
Idaho's top ranking for water quality is great news for citizens; however, we have a difficult challenge to maintain this enviable position. To protect water quality University of Idaho's Cooperative Extension Service (UICES) has implemented water quality programs in crop management, livestock/animal waste management, riparian management, domestic water quality, forestry and range management, wellhead protection, policy analysis, and youth activities. UICES will emphasize nutrient management, wellhead protection, and staff development in FY 1992. A brief summary of our FY92 objectives for each of these areas follows:
Staff Development for Water Quality Issues in Idaho:
SELECTING A HOME WATER TREATMENT
Treatment equipment for home systems should be selected to correct or prevent specific water quality problems. There are several major concerns:
treatment facilities have their limitations. A single unit cannot
correct all water quality problems.
MANAGING IDAHO'S GROUNDWATER
Second in a series of articles about aquifers in Idaho.
Groundwater management within Idaho is governed under the Appropriation Doctrine. This system gives priority groundwater rights to the senior (oldest) wells. In times of shortage, withdrawals from the junior (newest) wells can theoretically be curtailed to provide water for the senior wells. Under this system, the Idaho Department of Water Resources (IDWR) issues permits for new wells on the basis of needs and impacts on existing water rights. The department considers anticipated rate of aquifer recharge and estimated groundwater pumping levels. The IDWR is the state's primary water administering agency.
A drop in the water table known as groundwater mining is a problem in some parts of Idaho. It occurs when water is withdrawn from an aquifer more rapidly than it is replenished. As the water table drops, water pumping costs increase. Eventually, the users run out of water.
Areas with extensive groundwater mining may experience reduced flows to surface waters and subsidence (lowering of the land surface). Reduced surface flows occur because groundwater springs are commonly a major source of stream flow during dry periods. Subsidence occurs when the removal of water leaves underground spaces that collapse or underlying clay strata shrink when dried.
Idaho has 13 areas where the IDWR manages aquifer withdrawals due to groundwater mining. These problem areas are termed either Groundwater Management Areas (GWMA) or Critical Groundwater Areas (CGWA). In 1988 Idaho listed five GWMAs (Boise Front, Mountain Home, Bruneau-Grand View, Banbury Hot Springs, and Twin Falls). In these areas the IDWR must ensure that existing water rights in the area are unaffected by new construction.
More serious problems exist in eight CGWAs (Cinder Cone Butte, Blue Gulch, Artesian City, Cottonwood, West Oakley Fan, Oakley-Kenyon, Raft River, and Curlew Valley) where groundwater levels are declining at a rate that threatens a reasonable safe supply for existing users. The IDWR issues no new well permits in these areas, and it limits groundwater withdrawals.
For example, the Cottonwood/Oakley Fan aquifer declines an average of
about 5 feet per year and pumping lifts are 400 to 600 feet. Continued
declines in this area will soon make groundwater pumping for
agriculture economically unfeasible. Since aquifers can supply only a
limited amount of water, farmers in the CGWAs will either have to
increase water use efficiency or reduce irrigated acreage to maintain
this groundwater resource.
(R. L. Mahler)
NONPOINT SOURCES OF WATER
Contamination sources are grouped as point or nonpoint sources. Point sources can be individually identified by point of release. Point source pollution of groundwater in Idaho is primarily from underground injection of waste, solid waste disposal sites (landfills), chemical spills, industrial chemicals, and underground fuel storage tanks.
Nonpoint sources are land uses that are numerous, dispersed, and usually individually insignificant in generating groundwater contaminants. It is the cumulative impact of these land uses when occurring in high densities that results in groundwater contamination. Common examples are septic tanks and agriculture. Most nonpoint source groundwater contamination can be grouped into three major areas: agriculture, septic systems, and urban runoff.
Many groundwater contamination problems in Idaho are under investigation or cleanup. The relative importance of nonpoint sources and point sources of groundwater contamination within Idaho is unknown.
Agriculture -- Contamination of groundwater from agricultural activities can occur in several ways. They include (1) mixing and handling fertilizers and pesticides; (2) disposing of excess fertilizers and pesticides after application; (3) cleaning equipment after application; and (4) applying fertilizers and pesticides under conditions that result in movement of water and chemicals through the soil to the aquifer (usually poor water management).
Responsible management of fertilizers and pesticides is essential to maintaining and improving Idaho's groundwater resource. Evidence shows that high levels of nitrates (more than 10 parts per million nitrate-nitrogen) can be harmful to infants and livestock. Recent studies, although not conclusive, suggest a link between long-term exposure to high levels of nitrates (more than 25 ppm) and stomach cancer. Pesticides in groundwater appear to be a much greater threat to human health than nitrates; however, measurement and assessment of pesticides are incomplete.
Using Best Management Practices (BMPs) is the primary step in protecting groundwater quality in the agricultural sector. BMPs protect groundwater by encouraging integrated crop management practices such as integrated pest management, efficient irrigation management, and soil sampling and testing for fertilizer recommendations. These practices minimize leaching of chemicals and help protect aquifer recharge areas and wells. BMPs are currently voluntary in Idaho, but they are often encouraged through government cost sharing programs and payments.
Farmers can protect their aquifers by following pesticide and fertilizer label directions and seeking professional advice on the application and handling of fertilizers, pesticides, and irrigation. Also, it is essential that all chemicals be safely stored on concrete pads away from wells. Agrichemical equipment should be rinsed far from wells or any areas sensitive to contamination.
Septic systems -- Approximately 58 percent of Idaho's residents rely on septic systems. Septic systems remove the solids from household sewage and discharge the fluid portion into the soil. If the system is properly designed and maintained, the soil then adsorbs or breaks down the pollutants.
More often, improperly designed or maintained septic systems leach contaminants into the groundwater. Currently, permits are required for septic tank installation, but post installation monitoring is rare, and most regulations do not control septic system density in vulnerable groundwater settings. In densely populated areas this can threaten groundwater.
Residents can help minimize groundwater problems by having septic systems checked, maintaining the system with frequent pumping, and avoiding heavy use that can overload the system (for example, running several loads of laundry in one day).
Urban runoff -- The quality and quantity of urban runoff varies greatly depending on land uses, but the method of runoff management can determine whether groundwater becomes contaminated. Potentially harmful approaches include diverting untreated runoff into dry wells (shallow injection wells) or into unlined pits and basins. Contaminants found in urban runoff include nutrients, toxic metals, and oil and grease. In areas where salt is applied during snow removal, sodium and chloride may reach groundwater. Idaho has no comprehensive program to manage urban runoff, but local governments can modernize urban runoff systems to be more environmentally sound.
We can help decrease the toxicity of urban runoff by carefully handling all toxic materials. For example, garden fertilizers and pesticides should be applied according to label directions, and any excess should be stored carefully. They should never be emptied into a street gutter, poured down a drain, or set out with the weekly trash. Dispose of them at a certified hazardous waste disposal site or through a community household hazardous waste disposal.
Improper disposal of both empty and full chemical containers from
urban, agricultural, and industrial sources has also caused groundwater
contamination. These containers should never be discarded on land but
should be taken to a hazardous waste disposal site unless otherwise
specified on the label.
(R. L. Mahler)
TIMBER HARVESTING AND WATER
Forests are very important to Idaho's water quality. Forests cover over 41 percent of Idaho's total land area and receive more rainfall than nonforested areas. Twelve percent of Idaho forests are owned by over 37,000 farmers, retirees, and other nonindustrial private owners.
Prevention is the Cure
Under natural conditions water quality from forests is relatively high. When timber is harvested, sediment from soil disturbed by roads and skid trails may degrade forest water quality, especially during the first few years after harvest. The best way to maintain forest water quality at harvest is through well-planned and executed logging and road building.
Here are a few points for "water quality-friendly" timber harvesting:
For more detailed information on improving forest water quality, stop
by your local extension office and ask for PNW 915, Impacts of
forest practices on surface erosion, or other extension
publications on water quality or forestry.
(Chris Schnepf, Area Extension Forestry Agent)
WETLANDS IN IDAHO
Wetlands are some of the most productive and essential components of life. Historically they were naively considered wastelands which should be "reclaimed" for human uses, and consequently much of the country's wetlands were destroyed. Wetlands are lands which are transitional between aquatic and terrestrial systems where the water table is usually at or near the surface or the land is covered by shallow water.
The United States has lost approximately 56 percent of its original 215 million acres of wetlands. This is due to several factors related to population growth and government policy. For example, the Swamp Lands Act of the 1850s gave 65 million acres of federal wetlands to 15 states to be "reclaimed" for agriculture (drained or filled). While federal policies were not fully responsible for wetland loss, direct financial help was provided to convert wetlands to other uses through various federal laws until 1977. Currently 80 percent of the riparian areas (areas adjoining moving water) managed by the Federal Bureau of Land Management (BLM) are degraded from livestock. Although scientific proof makes the value of wetlands unquestionable, they continue to be destroyed at a rate of 350,000 to 400,000 acres per year since the 1950s (1 acre/min). Much of the remaining wetlands are under siege from pollution and degradation from altered water flow. Idaho is similar to the national average with approximately 50 percent of its original wetlands destroyed. There are currently about 95,140 acres of wetland remaining in Idaho, and 380 of these acres are lost every year. Losses are due to agriculture, urban growth, dams, and other activities. For example, 70 percent of the wetlands on the mainstem of the Snake River and its tributaries have been drowned from reservoirs. Palisades, Anderson Ranch, Black Canyon, and Alberi Falls reservoirs drowned 11,000 acres of wetlands and created a total of 75 acres of emergent wetlands and 28,000 acres of open water. Current losses in the lower 48 states are 87 percent from agriculture, 8 percent from urban growth, and 5 percent from other development and natural causes.
Why are Wetlands Important?
Wetlands are essential to the existence of most species of life in Idaho. More than 75 percent of Idaho's wild species depend on wetlands during some stage of their life cycle. Since wetlands represent only 1 percent of the land in Idaho, they are important to the balance of nature (food chain). In addition, they are essential to certain sectors of tourism, hunting, fishing, and recreation.
Wetlands are also very important to water quality. Wetlands are natural sediment and chemical filters. When water passes through a wetland it slows down due to friction with wetland vegetation and the flat nature of the area. As the water slows, sediment drops out of the water along with any chemicals which have adhered to the sediment. In addition, plants take up nitrates, phosphates, and other chemicals from the water. The result is cleaner water.
Wetlands also help stabilize the banks of waterways and help attenuate flood water. The root system of wetland plants stabilizes the soil near a shoreline or river, thus preventing erosion and improving fish habitat. Shoreline vegetation keeps the water cool for fish with shade, root systems reduce siltation which can cover spawning gravel, and roots allow the banks to become undercut, thus providing a refuge for fish.
Wetlands minimize floods by controlling water when it overflows its streambank. If there is an adjacent wetland, the water will flow out into the relatively flat wetland, slow down from friction with vegetation, and partially be absorbed into the ground. If streams are channelized and wetlands destroyed, floods can be much more severe and damaging.
Wetlands are also areas of groundwater exchange. If the groundwater
table is high, it will feed a wetland. If it is low, the wetland will
recharge the groundwater. A single wetland can provide both purposes
depending on the season. It can accumulate water during the wet season
and discharge water into the ground or stream when it is most needed
during the dry season.
(R. L. Mahler)
You probably already know about some of the following places where pesticides are used. To most people the word pesticide is synonymous with agriculture; however, pesticides are used in many industries and situations. These other situations may surprise you. All of the categories come from the list "EPA Site Categories for Preparing and Coding Pesticide Labeling." (Remember that "pesticides" include fungicides, herbicides, rodenticides, disinfectants and nematicides, as well as insecticides.)
DESK-TOP EXPERT SYSTEM TO PROTECT
Tony Trent and Ed Bechinski, faculty in PSES, will be leading a multiagency, multi-disciplinary software development project to help farmers devise field-specific pest and crop management plans that minimize leaching of fertilizers and pesticides to groundwater. Their work is one of four pilot demonstration projects funded by EPA in western region 10 under their "Pollution Prevention Through Agricultural Chemical Management" program. Region 10 was one of three EPA regions in 1991 to receive special funding for pilot educational projects targeting prevention of groundwater contamination by agrichemicals.
The goal of their work is to enhance groundwater quality by increasing on-farm use of Best Management Practices (BMPs) and Integrated Pest Management (IPM) methods. Their vision is to apply knowledge-based computer technology (i.e., artificial intelligence techniques) and design of interactive "decision aid" software that combines education functions (i.e., tutorial and training in the principles and practices of agricultural pest management, soil and water conservation, and crop production) with groundwater problem-solving capabilities (i.e., consultation, analysis, and recommendations).
The specific objectives are four-fold: (1) to educate farmers and farm-advisers about site conditions, soil characteristics, and properties of agrichemicals that can result in groundwater contamination; (2) to provide users of agrichemicals with a simple-to-use model that predicts relative potential for groundwater contamination from pesticides and fertilizers; (3) to deliver a unified set of the most current BMPs and IPM methods that can be brought to bear to minimize pesticide and fertilizer leaching potential; and (4) to strengthen interagency cooperation toward groundwater quality programming in Idaho.
Their premise is that IPM and BMP techniques have two roles to play in groundwater quality: as source-reduction technologies that reduce use of agrichemicals and as control technologies that reduce leaching to groundwater once agrichemicals are applied. Nationally, analyses suggest that 50 percent reductions in agricultural pesticide use could be achieved by using currently available IPM technology; in Idaho, we have documented up to 87 percent reductions in pesticide use without decreases in crop yield or quality among farmers who adopt IPM practices. Yet farmers and their advisers often lack easy access to the technical information and analytical tools needed to assess the impacts that agricultural chemicals can have on groundwater quality. There is an attempt to join individual BMP and IPM components into a comprehensive set of recommendations and then deliver them in an easy-to-use format.
Primary target audience is users of agri-chemicals (individual farmers) and those who influence farmers' use of agrichemicals, particularly Cooperative Extension System, Soil Conservation Service (SCS), industry field-men, private consultants, and distributors of agrichemical products. They believe that our software will be highly suitable for instructional use in the classroom and we accordingly target as secondary audiences undergraduate and graduate students in plant protection and natural resources, agricultural technical school faculty, and university teaching faculty.
Geographic focus for prototype design is the Spokane Valley-Rathdrum Prairie of eastern Washington and northern Idaho. They chose this hydrologic unit because the Idaho Division of Environmental Quality ranked it among Idaho's three most vulnerable aquifers to nonpoint contamination. Secondly, it affords an opportunity to link to two on-going water-quality/agrichemical-management projects: the Lake Creek State Agricultural Water Quality Project and the USDA-ASCS "Integrated Crop Management" (SP-53) program. Finally, the unit is small enough to be tractable for pilot system design yet includes both irrigated and non-irrigated crop production systems typical of those in the Snake River Plain of southern Idaho and the Columbia River Basin of east-central Oregon and Washington. Their work will have both statewide and regional application; we particularly intend that it serve as a model for the design of similar decision support systems in other regions.
Bechinski and Trent currently are awaiting final EPA sign-off and
expect to begin in September 1991 with a December 1992 completion date.
Preliminary planning sessions have been held and have resulted in an
informal memorandum of understanding between USDA-SCS and the
University of Idaho as well as statement of support from the
Kootenai-Shoshone Soil Conservation District. Their primary
collaborators are Kim Golden and Glenn Shea (USDA-SCS), Jerry Johnson
(Idaho-Washington RC&D Area), and UI colleagues Stephen Guy, Bob
Mahler, Glen Murray, Vickie Parker-Clark, Donn Thill, and Roger Veseth.
Trent and Bechinski look to our collaborators as technical
subject-matter experts and as agents of technology transfer and
evaluation. Together they have broad experience and knowledge in
systems analysis, crop protection and management, soil and water
conservation, and water quality.
(Ed Bechinski, Extension IPM Coordinator)
CES TO CO-SPONSOR WQ
The University of Idaho Cooperative Extension System, along with the Soil Conservation Service (SCS), Soil Conservation Commission (SCC), and Idaho Division of Environmental Quality (IDEQ) will be co-sponsoring a series of nutrient management workshops across the state in February 1992. These one day workshops are tentatively scheduled for Coeur d'Alene, Lewiston, Nampa, Twin Falls, Pocatello, and Idaho Falls. The agenda has not been set; however, topics will probably include: development and implementation of nutrient management BMPs, future FSA requirements, regulation of fertilizer rates, fertilizer recommendations, and soil sampling. UICES will be deeply involved in this effort. All faculty will be encouraged to attend. Details will follow in the next 30 days.
(R. L. Mahler)
FmHA WASTEWATER AID
The 1991 federal budget reveals that the Farmer's Home Administration (FmHA) will allocate $500 million in direct loans and $300 million in grants to help small communities install or upgrade water and wastewater treatment systems. The same requirements as previous years will apply to these funds, including:
Additional information can be obtained from the State Farmer's Home
(Source: EPA Region 10 WATERTALK)
LANDFILLS AND WATER
NIMBY ("Not In My Back Yard") is often the watch cry for citizens in an area where a landfill is reportedly to be sited. Siting a landfill is a highly emotional issue, and people often look for alternatives to landfills. Though the goal of an integrated solid waste management system is the reduced dependency on landfills, there is and will be a need for landfills in the United States. Nationwide over 80 percent of all waste is currently landfilled. Even with the potential of recycling, composting, and incineration, landfills will be necessary for ultimate disposal. Current best technology for recycling may suggest that 20 percent of waste be diverted to recycling. Best guestimates for compostable materials (yard wastes) are between 18 and 22 percent in urban areas, and incineration is, at best, a reducer of volume by 75 to 85 percent. Therefore, there will be a need for disposal of at least 25 percent volume of current waste plus ash residues. The bottom line is that a landfill is necessary and must go somewhere.
Leachate is the liquid that results from rain, snow, dew, and natural moisture percolating through waste. The liquids migrating through the waste dissolve salts, pick up organic constituents, and leach heavy metals. The organic strength of landfill leachate can be greater than 20 to 100 times the strength of raw sewage, making this "landfill liquor" a potentially potent polluter of soil and groundwater. This is why the issue of leachate is important in discussion on landfills. In open dumps, the material that leached would be absorbed into the ground and potentially move into groundwater, surface water, or aquifer systems. In new landfills and future landfills, it is required that collection systems be designed into the landfill to pump and collect the leachate for treatment.
The major intent in requiring all landfills to include nonpermeable
liners is to prohibit any leaching into the ground or groundwater
system. Given this current "best" technology, leachate should be less a
concern and more an issue to be addressed and technologically
engineered into a landfill.
(Adapted from Joe Heimlich, WASTEFACTS, Ohio State University)
HOW CAN WE PROTECT OUR
There are many things we can do to protect Idaho's groundwater. First, we must realize that groundwater does not belong to anyone but is shared among individuals, municipalities, and industries. Second, we must realize that each one of us contributes to the threat of groundwater contamination. Finally, we must decide to change the way we conduct our daily activities. For example, we can:
What are we throwing away? That is what "Le Project du Garbage" (The Garbage Project) tried to learn. Researcher and anthropologist William Rathje at the University of Arizona spent 13 years examining what people throw away, and more recently has studied the contents of landfills.
What's in Community Landfills?
Rathje studied 99 core samples and 9,000 pounds of municipal solid wastes from landfills in Illinois, California, and Arizona to develop the following:
8% by weight
|Organic yard wastes,
Organic, food, bones, peels, etc., 1%
16% by weight
|Ferrous & mixed
metals, 5% (metals 4% by volume)|
Plastic, 5% (9 to 12% by volume)
Glass, 2% (2% by volume)
Aluminum cans, 1%
34% by weight
38% by volume
Paper packaging, 10%
Other paper, 8%
Other cardboard, 3%
Fast-food packaging, 0.26%
42% by weight
28% by volume
|Includes rocks, dirt used covering layers of wastes in the landfill, organic materials that have degraded beyond recognition such as some yard wastes, objects that fit several categories.|
Biodegradability: Reality or Myth?
Biodegradation is a process where microorganisms secrete enzymes to chemically break down material they eat. Most people assume that biodegradable materials decompose rapidly, within a few weeks or months. Laws have been proposed in some states which would ban any packaging that does not decompose in one year. The Garbage Project discovered, however, that decomposition in landfills may not work. Biodegradation may be a longer process than we thought.
Food and yard wastes in easily identifiable form were found in the landfills even after being buried for years. Some decomposition of organics seems to have occurred, but substantial quantities of all kinds of paper also were found. Project Garbage found no major changes in the percentage of paper found in garbage dug up in the late1970s and that from the mid 1980s, which means paper was not decomposing rapidly. When Project Garbage dug up refuse deposited between 1970 and 1974, they found paper fractions still readable, and grass clippings, a 1972 T-bone steak, and five hot dogs still preserved.
Conditions are not ideal in landfills for biodegradation. Some food does degrade, but at a very slow rate or about 50 percent every 20 years, according to the Garbage Project. The remainder of the refuse in landfills seems to have retained its original weight, volume, and form even after 25 years, according to Rathje.
Do Household Wastes in Landfills Create Environmental
Studies by the Garbage Project have identified household products as possible sources of hazardous materials in landfills. Results of studies suggest that although household hazardous wastes comprise a small proportion of the total residential solid wastes (less than one percent), total quantities generated per year are high. Each household annually disposes of about 5.5 pounds of household hazardous waste.
Contamination of groundwater, surface water, soil, and air sometimes can be traced to improper disposal of household hazardous waste. For example, soil samples taken from one landfill dig were compared by the Garbage Project to natural sediment in the area and state. Preliminary results indicated that concentrations of lead, zinc, cadmium, and mercury may be higher in the landfill than in the surrounding natural soils. However, they suggest potential damages from household hazardous wastes to the environment or human health are unclear and require further study.
Some community landfills and open dumps are located and managed in ways
that have raised concern about the environment. In 1989, the Nebraska
Department of Environmental control sampled groundwater from five open
dump sites and found that groundwater degradation had occurred at all
the sites. Three sites showed degradation of groundwater quality. The
water sampled was not suitable for drinking and may have posed a health
risk to humans and livestock. However, these initial tests do not make
up a comprehensive assessment of the groundwater at these five
(Adapted by Tom Karsky from NebGuide, Published by Cooperative Extension, University of Nebraska, September 1990)
NEW WATER QUALITY
Three new water quality publications have recently come off the University of Idaho College of Agriculture printing presses. The first publication, CIS 900, Groundwater in Idaho, is an eight page publication jointly written by UICES and the Idaho Water Resources Research Institute (IWRRI). Topics covered in this publication include: definition of groundwater, groundwater and the hydrologic cycle, Idaho's aquifers, groundwater in Idaho's past, groundwater use today, managing Idaho's groundwater quantity, groundwater contamination, sources of pollution, and groundwater protection. This publication is available at no cost and can be obtained by calling Connie King in Ag Publications (208-885-7982).
Two new brochures on college water quality programs are also available. To order copies of these brochures contact R. L. Mahler, Soil Science Division (208-885-7025). New titles include:
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All contents copyright © 1997-2003. College of Agricultural and Life Sciences, University of Idaho. All rights reserved. Revised: January 3, 2003