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<br />Plan of W6rk
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<br />Each proJect was required to have a
<br />plan of work thai Indicated project
<br />goals, methods fpr achieving them,
<br />BMPs selected fpr cost-sharing, end a
<br />water quality monitoring program.
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<br />ground water; Massachusetts lacked thorough documentatiOn of pollutant
<br />sources.
<br />Two years into the project, the Kansas RCWP determined that the water;' 1
<br />use was not impaired and decided not to continue.
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<br />.. Water quality and land treatment monitoring must be Integral tothe~
<br />project - it cannot be an afterthought. A project's progress ~ and success,
<br />- can be tracked only by systematically comparing water quality data
<br />against prior data, including data collected before the project beganJ
<br />Knowledge of the watershed's hydrology is a critical factor in Elstimating how.
<br />long it will take (i.e., lag time) before the expected water quality impacts will;
<br />be detected. A trend monitoring program requires clearly stated objectives,
<br />appropriate experimental design, careful and consistent data collection, and'
<br />data analysis that accounts for natural variability in water quality. One, useful~
<br />approach may be to monitor a control watershed, where no land treatments,
<br />are implemented, to document effects of year-to-year variations in weather. ,
<br />Some specific findings related to monitoring are:
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<br />o The monitoring strategy must be appropriate for the water
<br />quality problem, the water resource type, and the project objec-
<br />tives. The most common monitoring strategy at the start of '
<br />RCWP was to compare water quality data from pre' and post-
<br />BMP implementation periods. Some projects use a trehd.
<br />analysis approach to associate improving trends in water
<br />quality over time with BM P implementation.
<br />Analysis of the Oregon, Florida, Idaho, and Utah water
<br />quality data has shown that a pre-BMP water quality data base
<br />of at least two- to three-years' duration facilitates documenting
<br />the effects of BMPs on water quality.
<br />Two to three years of post-BMP implementation data are also
<br />needed to evaluate the significance of any water quality
<br />change. For example, dry and wet cycles can complicate data
<br />interpretation and affect the significance of statistical resUlts.
<br />Consistent, rigorous monitoring protocols are essential to dete.ct
<br />changes in water quality.
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<br />o The most effective monitoring design for documenting BMP im-
<br />pacts on surface water quality is, the paired watershedap-
<br />proach. In this design, two watersheds or fields with generally
<br />similar physical characteristics, and ideally, land llse, are
<br />monitored for two to three years, with similar practices being
<br />used on both with respect to the treatment being tested., Follow-
<br />ing this initial calibration period one of the watersheds receives
<br />treatment (the other does not); then monitoring continues in
<br />both watersheds for two to three years after treatment becomes
<br />established. This controlled experiment accounts for weather
<br />and other factors that can obscure the water quality's response
<br />to the treatment.
<br />The Vermont RCWP used a paired watershed study to
<br />demonstrate the effects of spreading manure in winter, showing
<br />that more phosphorus - but less sediment - appeared in the
<br />runoff from the treated watershed.
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<br />o Nested monitoring wells (groups of two or more wells at the
<br />same location screened at different depths) are valuable for
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