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David J. Graczyk

Publications and source records attributed to David J. Graczyk.

22 records · Page 2Linked to original sources
USGS1997

Unit-area loads of suspended sediment, suspended solids and total phosphorus from small watersheds in Wisconsin

Watershed planners in the Wisconsin Department of Natural Resources (WDNR) and in Wisconsin county governments use estimates of loads of total solids and total phosphorus in streams for numerous management purposes. A few examples of these are to establish load reduction goals, to estimate the relative magnitude of nonpoint sources compared to point sources, and to estimate phosphorus loads to lakes. Solids and phosphorus are two of the most common nonpoint contaminants resulting from agricultural activity. Loads can be estimated either by monitoring the water quantity and water quality in a watershed or by modeling those same factors. Monitoring is the most accurate method for load estimation, but it is also time consuming and expensive. A simple method of estimating loads of chemical constituents or suspended solids in a watershed is to use unit-area loads that have been calculated from monitored data to estimate loads in watersheds where monitoring data are not available. A "unit-area load" is defined as the mass of a particular constituent transported by a stream, divided by the drainage area of the watershed.

Wisconsin↗
USGS1987

Average Annual Runoff in the United States, 1951-80

Runoff is the water in a river or stream that results from precipitation falling on the drainage basin. It is the net discharge into the stream from surface-water and ground-water sources with losses occurring from evapotranspiration and other consumptive uses. Runoff can be expressed by a variety of numerical values, but average depth of water over the drainage basin, in inches per year, probably is the most widely used unit of measurement. The map of average annual runoff (fig. 1), in inches per year, shows the geographical distribution of runoff in tributary streams for the years 1951—80; it describes the magnitudes and variations of runoff nationwide. The map was prepared to reflect the runoff of tributary streams rather than in major rivers in order to represent more accurately the local or small scale variation in runoff with precipitation and other geographical characteristics. The 1951–80 period was selected to conform to the period chosen by the World Meteorological Organization for study of climatic variations. The map should not be used to estimate the streamflow for any specific site. More detailed information for a specific area can be obtained from streamflow data collected by the U.S. Geological Survey, other Federal agencies, and State agencies.

Hydrologic Atlas↗
USGS1982

Effects of a floodwater-retarding structure on the hydrology and ecology of Trout Creek in southwestern Wisconsin

The primary effects of a floodwater-retarding structure (FRS) on the streamflow of Trout Creek, Wisconsin, are attenuation of flood peaks and extension of the time base of flood hydrographs. Reduction of flood peaks ranged from 58 to 91 percent during the study period from 1975 to 1979. There is an inverse relation between sediment concentration and outflow from the FRS during floods. As water went into storage in the flood pool in March 1976, the daily-mean total-sediment concentration in the FRS outflow dropped from 562 to 147 milligrams per liter. Sediment concentration subsequently increased to 809 milligrams per liter as the discharge from the FRS dropped; concentrations remained more than 400 milligrams per liter for several weeks thereafter. Most sediment stored in the flood pool during flood flows is released from the reservoir during subsequent reduced discharge. Sediment trapping efficiency of the FRS was about 7 percent for the 4-year period of the study. The bankfull capacity of the channel was reduced from 154 cubic feet per second upstream from the flood pool of the FRS to 65 cubic feet per second just downstream from the FRS. This latter discharge corresponds closely to the normal FRS outflow of 58 to 71 cubic feet per second during floods. Mean bankfull depth downstream from the FRS has adjusted to a value 45 percent less than upstream from the structure due to sedimentation of materials transported from the FRS during reduced flows. The hydraulic geometry and relationships between channel geometry and drainage area indicate little effect of the FRS near the mouth of Trout Creek, 2.4 miles downstream from the FRS. The arthropod fauna of Trout Creek is large and diverse. No effects of the FRS on these fauna were observed from April 1975 to October 1979. From fall 1975 to winter 1978, the most important factor contributing to increased brown trout egg survival and fry emergence in Trout Creek during a single reproductive season is higher water temperatures in the upper reaches of the stream. The FRS was not found to have any significant effect on trout reproduction during that period. From 1960 to 1979, winter floods seem to have had the greatest adverse effect on the survival of brown trout eggs and sac fry. Although construction of the FRS has eliminated some spawning gravels in the flood pool owing to sedimentation, the wild trout have adapted by using spawning grounds above the flood pool more extensively and intensively. The FRS has not blocked the upstream migration of spawning trout, but it has eliminated similar migrations of fish that compete with and prey on the trout. Controlled streamflows downstream from the FRS have had a stabilizing influence on the limited trout reproduction in this region.

Wisconsin↗