Number 50 November 1991
The National Water Quality Evaluation Project is in the process of completing the on-site evaluation of each of the Rural Clean Water Program (RCWP) projects. Objectives of the evaluation are 1) to assess: a) cooperation among project team members, committees, and agencies; b) the agreement between the documented water quality problem and the choice of solutions; c) the achievements of the project and individuals in relation to RCWP objectives; d) monitoring and the assessment of project impacts; and e) the effectiveness of the project and its progress toward improving water quality and 2) to compile lessons learned.
For each on-site evaluation, a team visits the project area, interviews project team members, reviews project activities, and reports results. Interviews with individual RCWP team members are conducted on a one-to-one basis. Survey questions have been designed to gather specific information on project elements, including administrative oversight, local and state coordinating committees, information and education, land treatment, and water quality monitoring and evaluation. A separate survey of producers and project team members will be used to determine factors that influence participation and perceptions of program effectiveness.
The evaluation team usually consists of one Soil Conservation Service or Cooperative Extension Service staff person from outside the project who has worked in the RCWP for several years and one National Water Quality Evaluation Project (NWQEP) team member from the NCSU Water Quality Group. For comprehensive monitoring and evaluation project evaluations and general projects that require more detailed evaluation, selected personnel from other RCWP projects or U.S. Environmental Protection Agency staff may be asked to participate.
The Agricultural Stabilization and Conservation Service (ASCS) headquarters in Washington, DC, has informed each state ASCS office of the evaluation and provided a copy of the survey questions in the draft proceedings of the 1990 RCWP Workshop. NWQEP contacts ASCS offices to schedule the site visits and interviews. Each RCWP project team will be asked to provide a list team members, their agencies, and all project elements in which each team member participated.
Project team members should review the survey questions before the evaluation team arrives. Please call Steve Coffey at NWQEP (919-515-3723) if you have any questions.
The cooperation of all who have participated in site visits has been exemplary. Thank you! We look forward to visiting the remaining projects and to talking with project staff about lessons learned from the RCWP.
Terry Maret
Bureau of Water Quality, Idaho Division of Environmental Quality
The Rock Creek Rural Clean Water Program (RCWP) Project, initiated in 1980, is one of five RCWP projects which received funding for comprehensive water quality monitoring and evaluation.
The Rock Creek watershed covers 198,400 acres of irrigated pasture and cropland, rangeland, woodland, and urban area in Twin Falls County, Idaho. While point source pollution was virtually eliminated by the end of the 1970s, Rock Creek was still carrying high loads of sediment and agricultural pollutants. The highly productive but highly erosive soils within the project area lie on gently sloping plains. The climate is semi-arid with annual precipitation averaging about nine inches. About 25 miles of Rock Creek, which flows northwest about 42 miles through Twin Falls County to the Snake River confluence, were involved in the project.
Before the RCWP project began, the water quality of Rock Creek was severely impacted, the largest single contributor to the impairment being irrigation return flows. A previous cooperative 208 project had demonstrated that sediment and pollutants could be reduced by 80% through farmers' serious involvement in the use of best management practices (BMPs). Thus, the Soil Conservation District supervisors felt confident that water quality in Rock Creek could be improved by similar procedures.
The goal of the RCWP project was to significantly reduce the amount of sediment, sediment-related pollutants, and animal waste entering Rock Creek. This goal was met.
The Agricultural Stabilization and Conservation Service (ASCS), coordinating closely with Twin Falls and Snake River Soil Conservation Districts (SCDs), administered the project. Additional interagency cooperation contributed greatly to the project's success. Several agencies participated in Information and Education activities, with the SCDs carrying the major responsibility. Technical assistance was provided through close cooperation among the Soil Conservation Service, Twin Falls SCDs, and cooperators. Water quality monitoring was conducted by the Idaho Department of Health and Welfare.
Nine BMPs were used in the project: permanent vegetative cover; animal waste control system; conservation tillage; stream protection; permanent vegetative cover on critical areas; sediment retention, erosion, or water control structure; improving irrigation system; fertilizer management; and pesticide management.
Terry Maret, Principal Water Quality Analyst
Gwynne Chandler, Senior Water Quality
Analyst
Water Quality Bureau, Idaho Division of Environmental Quality
1410 N. Hilton, Boise,
ID 83706
Tel: 208-334-5860
NCSU Water Quality Group staff reviewed 179 references on nonpoint sources for the annual review of 1990 literature published in the June, 1991, issue of the Journal of the Water Pollution Control Federation. The review covers nonpoint source (NPS) policy, economics, and planning; water quality and water resources - surface and groundwater; best management practices for NPS control; and NPS monitoring and modeling - modeling, monitoring, and load calculations. Reprints are available from the NCSU Water Quality Group (please refer to publication WQ-63 when placing your order).
Jean Spooner
NCSU Water Quality Group
One of the RCWP objectives is to determine the role of monitoring water quality and land treatment simultaneously to determine if water quality changes can be documented and associated with changes in land treatment. More specifically, RCWP is striving to document the effectiveness of nonpoint source pollution control practices at the project level, the watershed level, and/or at the subwatershed level.
A trend in the water quality data that is associated with BMPs does NOT alone document a cause-effect link between BMPs and water quality. A controlled experiment is the only way to confirm cause-effect relationships. Controlled refers to eliminating or accounting for all the factors that may affect the response to the treatment so the treatment effect alone can be isolated. Usually this control is obtained by subjecting the entire system to the same conditions, varying only the treatment variable and selecting replicates at random to assure that unmeasured sources of variability do not affect the interpretation. Ideally, in a watershed study, this includes an experiment with both treated and non-treated areas, repetitions, and each treatment being monitored for several years.
Except for projects that have paired watershed or nested watershed design, this is not generally being done in the RCWP. A controlled experiment can be performed at the plot level but is very difficult to obtain on a watershed level due to the limited resources and project goals calling for BMP implementation in all critical areas. However, the RCWP offers many watersheds where analyses of the land and water quality data can show strong associations between land use changes and water quality changes. These studies have important implications for demonstrating BMP effectiveness on a watershed scale.
Associations can be defined as a change in water quality that is correlated to a change in land use, specifically BMP implementation. Association is necessary but, by itself, is not sufficient to infer causal relationships. There may be other factors not related to the BMPs causing the changes in water quality such as changes in land use, rainfall patterns, etc. However, if the association is consistent, responsive, and has a mechanistic basis then causality may be supported (Mosteller and Tukey, 1977). Consistency means that the relationship between the variables holds in each data set in direction and amount. The data sets in RCWP include different subwatersheds, multiple years, and multiple stations. Responsiveness means that one variable will change accordingly if the other variable is changed in a known, experimental manner. Mechanism refers to the step-by- step path from cause to effect with the ability to make physical linkages at each step.
It is necessary to monitor land use changes relative to monitoring stations. For example, monitor land use on a subwatershed basis. This will allow for a pairing of water quality data with land use data.
Year-to-year variability is so large that at least 2 -3 years each of both pre- and post- BMP water quality data is required to give an indication that the improvement in water quality is related (i.e., associated) to land use changes in a consistent manner.
Seasonal effects may also be very large and should be accounted for in the analysis that links water quality changes to land treatment/use changes. Seasonal effects are due to seasonal land uses, seasonal climatic changes, and field conditions that change during a year.
In designing the monitoring system and subsequent statistical methods to detect changes over time or differences between treatments, one needs to increase the precision of the statistical analysis by removing as much as possible from the error term and eliminating bias. Spatial or temporal variability and autocorrelation should be accounted for because they can increase either the error or the bias of the estimated parameters. Also, correction for as much of the data variability due to meteorologic and hydrologic variables will reduce the residual errors and improve the power of the tests. For example, information such as rainfall, ground water levels, and streamflow need to be paired with water quality samples.
All changes in land use need to be monitored, not just BMPs, to help identify the water quality changes associated with BMPs alone. Land use changes such as conversion of row crops to pasture, acreage set aside, Conservation Reserve Program, changing in herd size or poultry flocks, closure of animal operations or implementation of non- contracted soil and water conservation efforts are important because they also affect water quality. Land use and BMPs need to be reported in quantified units that can be paired with water quality data. Examples include: acres treated by each BMP with consideration for relative efficiency from overlapping BMPs, acres treated by the BMPs systems to minimize double counting of land with multiple BMPs, tons of manure spread, miles of fencing, acres served by fencing, pounds fertilizer applied, etc.
The errors associated with the land use and water quality data need to be determined. It has been stated that "the data are only as good as the least reliable factor". For example, if you monitor water quality daily but only monitor the land use monthly, the information gained will only be as good as the monthly mean or median of the water quality. However, the monthly mean or median of several water quality samples is more reliable than just one grab sample in a month. The mean an estimate of central tendency and is more accurate when derived from a distribution of samples.
Mosteller, F. and J.W. Tukey. 1977. Data Analysis and Regression: Second Course in Statistics. Addison-Wesley Pub. Co., Reading, MA. 588 p.
Note: The author would like to thank Dr. Jack Clausen, Department of Natural Resources, University of Connecticut at Storrs, for his contributions to this article through valuable discussions regarding water quality monitoring programs for nonpoint sources.
McCullough, S. and J. Taggart (eds). 1991. 1990 Rural Clean Water Program National Workshop, September 17-20, 1990, Brookings, SD. South Dakota Dept. of Water and Natural Resources, Pierre, SD.
Proceedings from the 1990 Rural Clean Water Program National Workshop held in Brookings, South Dakota in September of 1990 have been published. Objectives of the workshop were to discuss how to put together the 10-year report for each Rural Clean Water Program project and, in that process, to help project teams analyze the data collected in the course of each project. Papers include RCWP project summaries, monitoring program descriptions, implementation results, monitoring results, information and education activities, institutional arrangements and economics, and water quality/ land use data analysis and reporting.
Free copies of the proceedings may be requested by contacting Jeanne Goodman, South Dakota Department of Water and Natural resources, Foss Building, Pierre, SD 57501 or the NCSU Water Quality Group (please refer to publication WQ-63 when placing your order).
U.S. EPA. 1990. Rural Clean Water Program: Lessons Learned from a Voluntary Nonpoint
Source Control Experiment. U.S. Environmental Protection Agency, Nonpoint Source Control
Branch, Washington, DC. EPA 440/4-90-012.
RCWP: Lessons Learned from a Voluntary Nonpoint Source Control Experiment provides an
informative general introduction to the concepts of nonpoint source pollution, the Rural Clean Water Program,
cost-sharing as an incentive for voluntary implementation of practices that can improve water
quality , and lessons learned from the RCWP in the areas of Best Management Practice (BMP)
effectiveness and federal-state-local cooperative programs. Profiles of selected RCWP projects,
a list of RCWP BMPs, and project contacts are also included.
Copies of the RCWP brochure are available from NWQEP, NCSU Water Quality Group (please refer to publication WQ-41 when placing your order).
Clark, W. H. 1991. Rock Creek Bibliography: Water Quality Related Publications, Rock Creek
Rural Clean Water Program, Idaho - References Through 1991. Division of Environmental
Quality, Idaho Department of Health and Welfare, Boise, ID.
The Idaho Department of Health and Welfare has published an annotated bibliography (626
references) of water quality and water resource related publications from the Rock Creek RCWP
project. For copies, contact: William H. Clark, Idaho Dept. of Health and Welfare, Division of
Environmental Quality, 1410 N. Hilton St., Boise, ID 83720-9000.
Purdue University and USDA Soil Conservation Service feature seven minutes of video-viewing
on low-cost gully erosion control structures. To order, contact: Purdue University Media
Distribution Center, 301 South 2nd, Lafayette, IN 47905-1092 (price $15).
Also available is the new video package entitled No-Till: The Common Cents Solution, produced
by ICI Americas Inc. This tape includes how to get started with no-till, a no-till farming guide,
a publication on the economics of no-till, questions and answers, a no-till technical sheet, and
other information. Copies are available from CTIC, 1220 Potter Dr., Rm. 170, West Lafayette,
IN 47906-1334, Tel: (317) 494-9555.
TVA engineers have developed software for water quality research named BETTER (Box
Exchange Transport Temperature and Ecology of a Reservoir). The model is designed for use by
researchers and water managers as a tool to enhance their understanding of reservoirs and to
develop strategies for improving water quality. For information contact: Gil Francis, Media Relations, TVA, 400 West Summit Hill Drive,
Knoxville, TN 37902, Tel: 615- 632-8031.
A series of sustainable agriculture booklets entitled Farming for the Future is available through
the Land Stewardship Project, an educational organization in Minnesota. The booklets examine
benefits from specific agricultural management practices, techniques, and equipment. Titles in
the series are: 1) Nitrogen Management, 2) Controlled (rotational) Grazing, 3) Basics of On-farm
Composting, and 4) Mechanical Weed Control.
Copies of the booklets can be ordered from the Land Stewardship Project, P.O. Box 815,
Lewiston, MN 55952 ($4 per booklet, or $12 for the set, plus appropriate sales tax).