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THE SAFE DRINKING WATER
ACT
The Safe Drinking Water Act was passed by Congress in 1974, and has
been amended several times since then. The Environmental Protection
Agency (EPA) is the federal government agency which writes the
regulations to carry out the provisions of the Act. The purpose of the
Act is to make sure that the drinking water supplied to the public is
safe and wholesome. EPA accomplishes this by setting national drinking
water standards which all water supplied to the public must meet. The
people who supply the water are responsible for making sure that the
water meets the standards. It is imortant to note that the Safe
Drinking Water Act does not provide funds for construction of water
systems or on-going operation and maintenance.
The Act was amended most recently in 1986. The amendments require the development of more drinking water standards and more technical requirements.
The federal drinking water program was designed to be delegated, which means that approved government agencies (usually states) carry out the program on a day-to-day basis. EPA provides guidance, technical assistance, and some financing to these agencies. Most states including Idaho have been delegated "primacy," or the authority to run the program. In the states and Indian lands which do not have primacy, EPA runs the program directly.
The Idaho Department of Health and Welfare (IDHW) keeps track of sample results, conducts detailed inspections called sanitary surveys, and takes enforcement actions such as imposing fines and penalties when necessary. IDHW also provides technical assistance to owners and operators of public water systems.
The requirements of the Safe Drinking Water Act apply to all public water systems. A public water system is one which provides piped water to at least 25 people or 15 service connections for at least 60 days per year.
Public water systems are divided into two categories: community systems and noncommunity systems. A community system serves people year-round (a small town, for example), whereas a noncommunity system serves people only for a portion of the time (a hotel or campground, for example). Different requirements apply to each type of water system. Systems serving the same people day after day, such as institutions or factories, may be considered community water systems for purposes of the Act. These are called non-transient-noncommunity water systems.
The three major types of requirements in the Safe Drinking Water Act are: (1) sampling and reporting, (2) record keeping, and (3) public notification. These are described below. Keep in mind that the owner or operator of the water system is responsible for meeting these requirements.
Sampling and Reporting. Each supplier of water must collect samples from the water system, take them to an approved laboratory for analysis, and send the results to the regulatory agency (usually the state or county health department). The type of analysis performed, the sampling frequency, and the location of the sampling point vary from system to system, and chemical to chemical. Some states perform the sampling for the systems in their state.
Record Keeping.The laboratory results, name of person who collected the samples, dates and locations of sampling points, steps taken to correct problems, sanitary survey reports, and other information must be kept on file by the water supplier.
Public Notification. Any time there is a violation of a
requirement, the public must be notified. Violations are divided into
two categories, Tier 1 and Tier 2, depending on the seriousness of the
violation. For example, a violation of a standard, indicating
contamination in the system, is more serious than a failure to meet a
compliance schedule imposed by the regulatory agency. Therefore, the
violation of the standard would be considered Tier 1, and more
extensive public notification would be required. The public notice must
meet certain minimum requirements concerning the way that they are
issued and their contents.
(Source: EPA, Region 9)
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FROM THE EDITOR
This is the fifth and final issue of WATER QUALITY UPDATE
for 1991. The first year of this newsletter has brought many
challenges. Over 70 articles have appeared in this newsletter in 1991
covering topics from drinking water and pesticide management and use to
riparian management. Approximately 10 percent of the current readers
will soon be asked to evaluate this newsletter for content and
timeliness.
Starting with the January 1992 issue, WATER QUALITY UPDATE will have an expanded mission and clientele. The College of Agriculture will team up with the Idaho Water Resources Research Institute (IWRRI) to expand our mission beyond agricultural and domestic water quality issues to include forestry, fisheries, wildlife, mining, legislative, and policy issues that affect water quality. It will be the first all -- University of Idaho newsletter. With this expanded newsletter we will be able to take relevant research information from a wide array of disciplines and make it available to targeted clientele. Our clientele will also expand beyond faculty as we strive to improve our education and information delivery not only to our traditional audience but to industry, local governments, and to other agencies.
I would like to thank all the professionals who have helped make this
newsletter a success during 1991. The following faculty have
contributed articles to this newsletter: Ed Bechinski (Entomology);
Merlyn Brusven (Entomology); Vickie Parker-Clark (District I); Stan
Gortsema (District IV); Tom Karsky (Ag Engineering); Dan Lucas
(District IV); Susan McNall (District I); Ernestine Porter (Home
Economics); Chris Schnepf (District I); Janice Stimpson (District IV);
Roy Taylor (Ag Engineering); Maureen Toomey (4-H); and Terry Tindall
(Soil Science). In addition to individual contributors, several
agencies including EPA, USDA-ARS, USDA-ES, USDA-CSRS, and Extension in
other states, have provided materials for this newsletter. I would also
like to thank Drs. L. D. Luft and G. A. Lee for their support of this
effort.
(R. L. Mahler)
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CSRS IN THE PRESIDENT'S WATER QUALITY
INITIATIVE
The Cooperative State Research Service (CSRS) administers a program
that is part of the President's Initiative on Water Quality. In
cooperation with the State Agricultural Experiment Station (SAES), CSRS
helps coordinate a network of well qualified scientists throughout the
U.S. who are joining together to develop solutions to problems
involving agricultural contamination of groundwater. Through a peer
review process, research grants are awarded annually to the best
qualified scientists and laboratories. Knowledgeable scientists from
across the nation constitute the merit panels and review each project
to identify those which are recommended for support. Under this
procedure, up to 20 percent of the submitted proposals have been
selected for funding each year.
The Initiative Goals -- The overall goal of the President's Initiative is to safeguard and enhance the quality of the nation's surface waters and groundwaters in the presence of sustained agricultural activity. To achieve this goal, CSRS is committed to improving and expanding knowledge about the relationships between agricultural practices and water quality.
National Components Research Program -- The CSRS Water Quality Special Research Grants Program seeks to develop a comprehensive package of new research to enhance water quality. The goals of the program are: to identify and assess actual and potential sources of contamination in order to develop schemes for prevention; to further our understanding of persistence, disappearance, and transport of potentially toxic agricultural chemicals; to work toward restoration of contaminated soils and water; and to evaluate the sociological and economic implications of needed changes. Scientists in SAES and others in well established disciplines associated with this country's agriculture are keenly qualified to perform this research.
The focus to date has been in five areas having an impact on the water quality problem. These areas and the number of projects initiated in each during past years, are shown below.
| Projects Initiated | ||||
|---|---|---|---|---|
| Areas of Research | 1989 | 1990 | 1991 | Total |
| Fundamental Processes | 7 | 11 | 11 | 29 |
| Diagnostic Methodology | 6 | 12 | 8 | 26 |
| Production Systems | 3 | 13 | 14 | 30 |
| Decision Aids & Information Systems | 6 | 6 | 6 | 18 |
| Socio-Economic Implications | 1 | 4 | 5 | 10 |
| TOTALS | 23 | 46 | 44 | 113 |
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URBAN RIPARIAN
MANAGEMENT
Streams are unique in their looks and functions, but all streams have
physical and biological capabilities that provide them with the ability
to support both human and wildlife resources. When a stream is outside
an urban area, management of the riparian zone is less affected by
human impact. That is to say, less people movement or traffice vs.
animal or farming practices.
When a stream is surrounded by a dense urban area such as Boise, Spokane, or Idaho Falls, the stream's character usually changes. It still has the potential to be a wildlife corridor -- a greenbelt separator between neighborhoods or a wetland ecosystem with its own completeness. It can also be a center for recreation with an extremely high amount of use. However, riparian areas in these settings become increasingly difficult to manage, because of the high demands placed on them due to urbanization.
The stream's shape, materials, associated vegetation, and riparian landscape dictate how effective the corridor will be as a resource. For example, as a city develops, there becomes less soil surface area exposed to absorb water from rainfall, thereby increasing the potential for flooding and decreasing sediments going into the stream. When this occurs there is a greater chance for deep incision. This quickly changes the effectiveness of the stream and reduces the riparian vegetation. A stream can be landscaped to help reduce the velocity associated with high water flows.
A good example of urban streamside management is the Boise River as it flows through downtown Boise. Recently Hal Swenson, a soil scientist with the Soil Conservation Service stationed in Boise, and I evaluated the river from Park Center to Ann Morrison Park. This section of the river is heavily used and in some places "people traffic" is very intense. Trails have been incised into the steep banks for easier access to the water. These trails increase sediments into the river with the potential reduction of fish habitat. Although the affected areas are small, they might add up to be more serious if measures are not taken to reduce the bank erosion.
Although the Boise River is used throughout the year, there is a single event called the Boise River Festival which has the potential for significant negative impact on the stream and the associated riparian vegetation. Last year was the first for the festival. The response from the public was tremendous. An estimated 125,000 people watched or participated in the event. Crowds at times 10 people deep lined up on steep banks along the south side of the river. This type of impact could seriously affect the riparian area if measures are not taken to lessen the impact. The area where the floats were put into the river was devoid of vegetation. Whether it was completely associated with the festival is not clear, but management considerations could be implemented to decrease this impact.
This is just one example of a riparian area which is heavily used in an urban Idaho setting. Recommendations for repairing other damaged areas of riparian zones might include the following:
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THE GREEN INDEX: IDAHO
AGRICULTURE
In the September issue of WATER QUALITY UPDATE I
presented some general information developed by the Institute of
Southern Studies in Durham, North Carolina, about Idaho's environmental
health. This information is published in a book, "1991-92 Green Index:
A State-by-State Guide to the Nation's Environmental Health," by Bob
Hall and Mary Lee Kerr (1991 Island Press, Washington, DC).
The Institute of Southern Studies gives Idaho a very low score (rank 45 out of 50 states) for agriculture and its impact on the state's environment. Only Nebraska (46), Minnesota (47), Alaska (48), California (49), and Arizona (50) rank lower. Some of the categories which were used to rate the states were fertilizer use per capita, herbicide use per acre of cropland, pesticide use per capita, pesticide tainted groundwater, unsafe levels of nitrates in wells, irrigated cropland, cropland erosion, conservation tillage, acres in conservation reserve, and agriculture as a percentage of state gross product. The Green Index ranks states from 1 to 50 with 1 being environmentally safe and 50 the worst environmental performance.
Compared to other states Idaho has a greater fertilizer use per capita (68.3 tons) than 45 other states. Idaho's per capita pesticide use (6.4 lb) is greater than 41 other states. The study also reports that Idaho has a larger percentage of pesticide tainted groundwater (22.5 percent) than 38 other states.
The Green Index reports that Idaho ranks 38th in cropland erosion with an annual loss of 8.1 tons of soil per acre per year. Conservation tillage is practiced on 25.3 percent of cropland (rank 20) in Idaho; however, only 0.3 percent of Idaho's cropland is in conservation reserve (rank 35). Agriculture produces 11 percent of Idaho's gross product. Only four states -- South Dakota, North Dakota, Nebraska, and Iowa -- are more dependent on agriculture than Idaho.
I generally do not agree with Idaho's rankings in several areas of agriculture. For instance, there is no reason to believe that Idaho has a greater percentage of its groundwater contaminated by pesticides than Washington or Oregon. I feel the source that provided Idaho numbers for this index was poor -- recent evidence supports my belief. However, it is important for you to know these figures are being circulated so that you can respond to questions.
How does Idaho compare to neighboring states in regard to agriculture and the environment? Idaho's record is generally worse than Washington and Oregon but similar to Montana and Utah. The following tables are put together with data from the 1991-92 Green Index:
| State | % | Rank |
|---|---|---|
| Utah | 0.0 | 1 |
| Oregon | 0.6 | 8 |
| Montana | 3.7 | 14 |
| Washington | 6.9 | 25 |
| Idaho | 22.5 | 39 |
| USA | 14.9 | -- |
| State | Pounds | Rank |
|---|---|---|
| Montana | 0.2 | 2 |
| Washington | 0.4 | 8 |
| Oregon | 0.8 | 13 |
| Idaho | 0.9 | 15 |
| Utah | 1.0 | 19 |
| USA | 1.2 | -- |
| State | Pounds | Rank |
|---|---|---|
| Utah | 0.5 | 9 |
| Washington | 1.9 | 22 |
| Oregon | 1.9 | 23 |
| Idaho | 6.4 | 42 |
| Montana | 6.5 | 43 |
| USA | 3.9 | -- |
| State | Tons | Rank |
|---|---|---|
| Utah | 6.0 | 12 |
| Washington | 18.2 | 31 |
| Oregon | 21.2 | 32 |
| Montana | 41.4 | 43 |
| Idaho | 68.3 | 46 |
| USA | 18.5 | -- |
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MANAGING NUTRIENTS WISELY WATER
QUALITY WORKSHOP
Dates have been set for the Managing Nutrients Wisely Water Quality
Workshop next February. 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) are cosponsoring this series of nutrient management
workshops. The dates and places are as follows: February 20, Lewiston;
February 21, Coeur d'Alene; February 24, Nampa; February 25, Twin
Falls; February 26, Pocatello; and February 27, Idaho Falls.
The one-day agenda includes the following topics: (1) the state of
water quality in Idaho; (2) nitrogen and phosphorus movement in soils;
(3) rotations, animal wastes, and nutrient credits; (4) nutrient
management best management practices (BMPs); (5) regulations -- what
will our future be like; and (6) current nutrient management programs.
All UI College of Agriculture faculty will be encouraged to attend.
(R. L. Mahler)
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IFB WELLHEAD SURVEY -- PROJECT
REPORT
As of November 1, 1991, the wellhead survey program coordinated by the
Idaho Farm Bureau had completed six sampling events covering 10 Idaho
counties -- Ada, Benewah, Canyon, Cassia, Gem, Jerome, Latah, Minidoka,
Payette, and Twin Falls. A total of 2,539 samples have been run for
nitrates including 1,485 samples from private wells and 1,054 control
and quality assurance samples.
The Idaho Private Wellhead Sampling Program was initiated and coordinated by the Idaho Farm Bureau Federation (IFBF). Coordinator Jim Yost, Idaho Farm Bureau Federation's public affairs director, in conjunction with local farm bureaus (counties) collected samples from various counties at specified times over the past 15 months.
This program was truly a cooperative effort as five different government agencies and the Idaho Farm Bureau Federation united to make the program a success. The Idaho Department of Agriculture (IDA), Soil Conservation Service (SCS), and the University of Idaho Cooperative Extension System (UI CES) assisted with program logistics, sample bottle distribution, and dissemination of information. The University of Idaho College of Agriculture's Analytical Laboratory (UI LAB) had major roles in planning and designing the quality assurance phase of the analytical part of the program and analyzed all samples for nitrates. The Idaho Division of Environmental Quality (IDEQ) designed the quality assurance plan for the field effort, the questionnaire, and sampling procedures for the public.

Quality control in this sampling project was the top priority. Blind spiked samples and blanks were randomly dispersed with farmer-provided samples to assure top quality. In addition, in some cases, duplicate farm wellhead samples were included. Nitrates were determined on water samples by the UI LAB in Moscow. After collection, a preservative was added to the sample before shipment to Moscow. Samples were run in the laboratory within 72 hours after collection. The most modern analytical techniques and equipment were used in this operation. A high degree of confidence should be placed on the numbers obtained from these samples.
Twin Falls County -- August 16, 1991. Over 180 samples were received from rural residents. Only 3 percent of the sampled wells contained nitrate-N levels greater than 10 ppm. Over 19 percent of the wells contained less than 2.0 ppm nitrate-N.

Latah and Benewah Counties -- September 24, 1991. Over 75 samples were received from rural residents. Only 5 percent of the sampled wells contained nitrate-N levels greater than 10 ppm. Over 68 percent of the wells contained less than 2.0 ppm nitrate-N.

Over the next 24 months this program will be brought to most Idaho
counties. The latest occurred on November 12, 1991 in Bonner County
(data not yet available). CES has and will continue to prepare county
by county brochures which provide the data from each sampling event as
they occur. Brochures can be obtained directly from the individual
county extension office or from R. L. Mahler. Current titles
include:
| WQ-5 | Twin Falls County |
| WQ-6 | Canyon County |
| WQ-7 | Payette and Gem Counties |
| WQ-8 | Ada County |
| WQ-9 | Cassia, Minidoka and Jerome Counties |
| WQ-10 | Latah and Benewah Counties |
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NATIONAL ANIMAL WASTE
WORKSHOP
Commodity groups and individuals representing aquaculture, beef, dairy,
poultry, and swine developed suggestions for additional educational and
technical assistance, and research, necessary to improve each group's
response to water quality concerns.
The consensus was developed at the National Livestock, Poultry, and Aquaculture Waste Management Workshop held in Kansas City, MO, in July. Extension Service, Soil Conservation Service, Agricultural Research Service, Cooperative State Research Service, the Tennessee Valley Authority, the U.S. Environmental Protection Agency, and Michigan State University jointly sponsored the workshop.
All agreed that waste from animal production and processing has long been associated with contamination of ground and surface waters in the United States. Federal and state agencies, and the animal industries, are actively seeking ways to minimize the negative effects of animal production on water quality. Commodity group representatives requested increased educational programs and technical assistance to cover all aspects of animal waste management and water quality.
The general session presented the latest available information on animal waste. Participants also refined recommendations that will improve communication and cooperation between government agencies, environmental groups, farmers, colleges and universities, and the individual industries.
For additional information contact Richard Reynnells, ES-USDA National Program Leader, Poultry Science, Room 3334, South Building, Washington, DC 20250-0900. Telephone 202-447-4087.
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POINT SOURCES OF WATER
POLLUTION
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.
Injection wells -- Underground injection of waste has been a common practice for disposal of irrigation runoff and industrial waste. Injecting waste into the ground has the advantage of being generally inexpensive and of minimizing impacts on surface waters. However, injection wells are often not deep or secure enough to avoid contamination of the local aquifer. Injection wells in parts of Idaho are being closely monitored by state and federal agencies. Because of potential groundwater contamination it is likely that injection wells will be out of use by the end of the decade.
Solid waste disposal sites -- When precipitation moves downward through solid waste it can dissolve some of the contents and carry them to the groundwater. Although modern soil waste disposal sites are lined to prevent leachate from entering the groundwater, sites that are at least 5 to 10 years old are generally not lined.
Underground storage tanks -- Underground storage tanks and their contents, whether at the local gas station or a major industrial complex, pose a widespread threat to groundwater. The major cause of leaking is corrosion or leaky pipe fittings. Many underground tanks are made of steel, which usually rusts and will eventually leak unless treated with special precautions.
Industrial chemicals -- Most hazardous wastes generated by large industrial facilities are currently regulated as point sources of pollution, but preregulation activities have caused groundwater contamination in many areas. In addition, users and disposers of small amounts of industrial chemicals may not have access to the best available disposal procedures or may not use them. This creates the potential for groundwater contamination.
It is the public's and the government's role to demand careful handling
of materials and the use of Best Available Technology in
pollution control, chemical storage, and waste disposal.
(R. L. Mahler)
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FARM*A*SYST -- NATIONAL COOP
PROGRAM
A national cooperative program will soon be underway to assist farmers
and their rural neighbors in identifying and reducing potential and
current sources of groundwater and drinking water contamination from
farmsteads and rural residences. This program, supported by Extension
Service (ES), Soil Conservation Service (SCS), and the Environmental
Protection Agency (EPA), stems from enthusiastic response to
Farm*A*Syst, an education and assessment tool developed by Wisconsin
and Minnesota Cooperative Extension Services and Region V EPA. Current
agricultural water quality programs, including the USDA WAter Quality
Initiative, focus on reducing water contamination risks from field
practices.
Farm*A*Syst is unique because it comprehensively addresses potential groundwater contamination from 10 significant potential sources near the farmstead drinking water well. Farmers and rural residents use Farm*A*Syst to assess current structures and practices such as pesticide and fertilizer mixing, loading practices, and maintaining petroleum product storage tanks. Site conditions that affect pollution vulnerability are assessed to help farmers prioritize actions to reduce or prevent pollution.
Farm*A*Syst identifies technical expertise and financial assistance to
enable implementation of preventive and corrective actions. Nationwide
program expansion will facilitate rapid, cost-effective modification of
the materials and implementation of the program so that local needs,
policy requirments, and site condition in other interested states are
accurately reflected. For more information, contact Susan Jones at
(608) 262-2031, or Gary Jackson at (608) 262-1916.
(Source: USDA)
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DELONG & BRUSVEN PUBLISH RIPARIAN
MANAGEMENT PAPER
Michael D. Delong, former graduate student, and Merlyn Brusven,
professor of entomology, recently had a paper published,
"Classification and Spatial Mapping of Riparian Habitat with
Applications Toward Management of Streams Impacted by Nonpoint Source
Pollution" in Environmental Management (15:565-571). The authors
introduced a riparian habitat classification system, demonstrated its
use in a GIS format, and discussed potential management applications of
GIS.
Delong and Brusven tested a riparian habitat classification system for field efficiency on the Tom Beall Creek watershed, an agriculturally impacted third-order stream in the Clearwater River drainage in Nez Perce County. The classification system was simple to use during field applications and provided a good inventory of riparian habitat. After successful field tests, spatial maps were produced for each component using Professional Map Analysis Package (pMAP), a GIS program. With pMAP a map describing general riparian habitat condition was produced by combining the maps of components of riparian habitat, and the condition map was integrated with a map of soil erosion potential in order to determine areas along the stream that are susceptible to nonpoint source pollution inputs. Integration of spatial maps of riparian classification and watershed characteristics has great potential as a tool for aiding in making management decisions for mitigating off-site impacts of agricultural nonpoint source pollution.
A reprint of this article can be obtained by contacting M. A.
Brusven.
(R. L. Mahler)
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TIPS TO PREVENT WATER
CONTAMINATION
The following tips are furnished by USDA-ES as an educational aid
directed at protecting water quality:
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ORSER RECEIVES USDA WQ
GRANT
Dr. Cindy S. Orser, assistant professor of bacteriology, has been
awarded a FY1991 CSRS Water Quality grant. She will receive $70,000 to
study the application of GEMS in remediation of chloroaromatics.
Professor Ron L. Crawford and Luying Xun are project
co-investigators.
In FY1991 a total of 44 of 254 proposals submitted were funded. This is the second year in a row the University of Idaho Agricultural Experiment Station has successfully competed against other land-grant universities in the United States.
Last year professors Crawford (B&B), Thill (Plant Science), and Homan (Entomology) were awarded one of CSRS's competitive water quality grants.
A call for FY1992 CSRS Water Quality proposals is anticipated in the
near future.
(R. L. Mahler)
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WATER QUALITY EDUCATION IN
SOUTHEASTERN IDAHO
Water quality is an issue of concern for all Idahoans, but particularly
for rural residents. Community domestic water supplies are subject to
periodic testing as required by law. However, rural domestic water
users do not receive benefit of regular testing. Rural domestic water
users are entirely dependent upon their own monitoring activities for
water quality assurance. The University of Idaho District IV Water
Quality Working Group conducted a series of 13 water quality education
workshops designed to raise the awareness of rural residents to water
quality concerns. Domestic water issues, agricultural groundwater
impacts, and surface water concerns were addressed in each of the
workshops. To stimulate interest and relate general water quality
principles to individual water users, water samples supplied by
workshop participants were tested for nitrate level and presence of
coliform bacteria.
Dependence on groundwater helped to stimulate 199 rural water users to have their water tested for nitrates and presence of coliform bacteria. Supplemental information gathered on each well included: well depth, and distance of the wellhead from septic systems, corrals, irrigation canals, and irrigated fields. Subsequently analysis was conducted to investigate the association between the supplemental information gathered and nitrate levels and coliform presence. Initial assumptions were that an association would exist between coliform presence and distance between wellhead and septic system and corral, and an association between nitrate level and distance between wellhead and corrals, irrigation canals, and irrigated fields. Well depth was assumed to have an association with both nitrates and coliform presence.
Results from the analysis indicated that there was not a strong association between the parameters in the initial assumptions. There were only six samples or 3.01 percent with nitrate levels above the EPA recommended maximum for domestic water of 10 ppm. Of those six samples, none were within 100 feet of an irrigation canal, only 3 were between 50 and 100 feet of a corral, and only 1 was between 50 and 100 feet of an irrigated field. Well depth did not have a strong association with nitrate level. In fact, the well with the highest nitrate level was found on a dry farm with no livestock and a well depth in excess of 320 feet. Likewise, coliform bacteria presence did not have a strong association with well depth or proximity to septic systems or corrals. A total of 10 samples tested positive for coliform presence. None of those 10 samples were taken from wells with septic systems within 50 feet of the wellhead. Interestingly, 21 samples taken from wells with a septic system within 50 feet tested negative for coliform presence. Two samples tested positive for coliform with corrals within 50 feet of the well, while 11 tested negative.
The knowledge gained from this program is of great use for rural
residents. The indications are that regardless of whether guidelines
for proximity of wellhead to external influences are followed, the only
assurance of domestic water quality is that provided by periodic
testing. Rural residents are encouraged to test their water for nitrate
level and coliform presence annually.
(D. E. Lucas, J. K. Stimpson, and S. R. Gortsema)
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WATER QUALITY INFORMATION
CENTER
What is the Water Quality Information Center? The Water Quality
Information Center (WQIC) is part of the National Agricultural Library
(NAL), which is an agency of the U.S. Department of Agriculture. The
Center was established in 1990 as part of USDA's coordinated plan
responding to the Presidential Initiative on Water Quality. WQIC serves
as a focal point in the dissemination of information related to water
quality and is seeking ways to facilitate communication among
interested professionals, organizations, and members of the general
public.
The WQIC can help agriculture and home economics professionals in various ways including by:
Special concerns include:
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USDA-CSRS WATER QUALITY RESEARCH
PROGRESS
A recent sampling of CSRS progress under the President's Water Quality
Initiative to keep pesticides and fertilizers out of ground and surface
water includes:

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Comments to webmistress: karenl@uidaho.edu
All contents copyright © 1997-2003. College of Agricultural and Life Sciences, University of Idaho. All rights reserved. Revised: January 3, 2003