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Judy A. Horwatich

Publications and source records attributed to Judy A. Horwatich.

8 recordsLinked to original sources

Assessment of conservation management practices on water quality and observed trends in the Plum Creek Basin, 2010–20

The U.S. Geological Survey and University of Wisconsin–Green Bay collected hydrologic and water-quality data to assess the effectiveness of agricultural conservation management practice (CMP) implementation at mainstem Plum Creek and west Plum Creek in northeastern Wisconsin. These two subbasins cover 88 percent of the Plum Creek Basin (Hydrologic Unit Code 12), which is a subbasin of the lower Fox River Basin. A published total maximum daily load report for the lower Fox River Basin rated Plum Creek as one of the greatest contributors of total suspended solids (TSS) and total phosphorus (TP) draining into the lower Fox River. To reduce TSS and TP exports from Plum Creek, additional cropland conservation practices and watercourse protections were applied between 2012 and 2020. To detect water-quality trends, data were collected during 2010 to 2020 at mainstem Plum Creek and 2013 to 2020 at west Plum Creek. The project used two methods to evaluate CMP effectiveness. The first method focused on evaluating water-quality changes between initial and post-CMP implementation periods during rain- or snowmelt-induced runoff events (hereafter referred to as “events”). In this approach random-forest models were developed to account for environmental factors which influence water quality. Model residuals from the two time periods were compared to determine the significance of water-quality changes associated with CMP implementation for mainstem and west Plum Creek Basins. The second method used a Weighted Regressions on Time, Discharge, and Season time-series approach to examine changes in water quality during the entire study period in mainstem Plum Creek. Results from both methods indicated there were minimal water-quality changes in TSS concentrations and flow-normalized delivery during runoff events during the 10-year period from 2010 to 2020; however, TP concentrations during low streamflow (less than 3 cubic feet per second [ft 3 /s]) may have decreased. The lack of observed improvement may be attributable to any of the following: variability in weather and hydrologic conditions, insufficient post-treatment data, additional cropland being converted to corn production, above average rainfall, streambank degradation, acute and legacy sources of phosphorus from farm fields, excessive/vulnerable manure applications and spills, and point-source discharges.

Wisconsin

The effect of particle size distribution on the design of urban stormwater control measures

An urban pollutant loading model was used to demonstrate how incorrect assumptions on the particle size distribution (PSD) in urban runoff can alter the design characteristics of stormwater control measures (SCMs) used to remove solids in stormwater. Field-measured PSD, although highly variable, is generally coarser than the widely-accepted PSD characterized by the Nationwide Urban Runoff Program (NURP). PSDs can be predicted based on environmental surrogate data. There were no appreciable differences in predicted PSD when grouped by season. Model simulations of a wet detention pond and catch basin showed a much smaller surface area is needed to achieve the same level of solids removal using the median value of field-measured PSD as compared to NURP PSD. Therefore, SCMs that used the NURP PSD in the design process could be unnecessarily oversized. The median of measured PSDs, although more site-specific than NURP PSDs, could still misrepresent the efficiency of an SCM because it may not adequately capture the variability of individual runoff events. Future pollutant loading models may account for this variability through regression with environmental surrogates, but until then, without proper site characterization, the adoption of a single PSD to represent all runoff conditions may result in SCMs that are under- or over-sized, rendering them ineffective or unnecessarily costly.

Water

Effects of best-management practices in Bower Creek in the East River priority watershed, Wisconsin, 1991-2009

Hydrologic and water-quality data were collected at Bower Creek during the periods before best-management practices (BMPs), and after BMPs were installed for evaluation of water-quality improvements. The monitoring was done between 1990 and 2009 with the pre-BMP period ending in July 1994 and the post-BMP period beginning in October 2006. BMPs installed in this basin included streambank protection and fencing, stream crossings, grade stabilization, buffer strips, various barnyard-runoff controls, nutrient management, and a low degree of upland BMPs. Water-quality evaluations included base-flow concentrations and storm loads for total suspended solids, total phosphorus, and ammonia nitrogen. The only reductions detected between the base-flow samples of the pre- and post-BMP periods were in median concentrations of total phosphorus from base-flow samples, but not for total suspended solids or dissolved ammonia nitrogen. Differences in storm loads for the three water-quality constituents monitored were not observed during the study period.

Wisconsin

Parking lot runoff quality and treatment efficiencies of a hydrodynamic-settling device in Madison, Wisconsin, 2005-6

A hydrodynamic-settling device was installed in 2004 to treat stormwater runoff from a roof and parking lot located at the Water Utility Administration Building in Madison, Wis. The U.S. Geological Survey, in cooperation with the Wisconsin Department of Natural Resources, the City of Madison, cities in the Waukesha Permit Group, Hydro International, Earth Tech, Inc., National Sanitation Foundation International, and the U.S. Environmental Protection Agency, monitored the device from November 2005 through September 2006 to evaluate it as part of the U.S. Environmental Protection Agency's Environmental Technology Verification Program. Twenty-three runoff events monitored for flow volume and water quality at the device's inlet and outlet were used to calculate the percentage of pollutant reduction for the device. The geometric mean concentrations of suspended sediment (SS), "adjusted" total suspended solids (TSS), total phosphorus (TP), dissolved phosphorus (DP), total recoverable zinc (TZn), and total recoverable copper (TCu) measured at the inlet were 107 mg/L (milligrams per liter), 92 mg/L, 0.17 mg/L, 0.05 mg/L, 38 μg/L (micrograms per liter), and 12 μg/L, respectively, and these concentrations are in the range of values observed in stormwater runoff from other parking lots in Wisconsin and Michigan. Efficiency of the settling device was calculated using the efficiency ratio and summation of loads (SOL) methods. Using the efficiency ratio method, the device reduced concentrations of SS, and DP, by 19, and 15, percent, respectively. Using the efficiency ratio method, the device increased "adjusted" TSS and TZn concentrations by 5 and 19, respectively. Bypass occurred for 3 of the 23 runoff events used in this assessment, and the bypass flow and water-quality concentrations were used to determine the efficiency of the bypass system. Concentrations of SS, "adjusted" TSS, and DP were reduced for the system by 18, 5, and 18, respectively; however, TZn increased by 5 percent. Some of the TSS concentrations were "adjusted" to add the particles that remained on the sieves during sample processing. The loads of SS, "adjusted" TSS, and DP were reduced using the SOL method for the settling device by 38, 9, and 19 percent, respectively, and TZn increased by 13 percent. For the bypass system, the loads of SS, "adjusted" TSS, and DP had percentage reductions of 39, 12, 22, respectively, however TZn increased by 4 percent. The SOL method produced percentage reductions for SS and 'adjusted" TSS that were twice those for the efficiency ratio method. Removing the two large runoff events on August 23 and 24, 2006, from the SOL calculation brought the reduction for SS down to 16 and increased "adjusted" TSS by 4 percent. The two large runoff events were anomalies in that the runoff volumes and dissolved solids concentrations were greatly increased by overflow from an adjacent recycling facility. The SOL method was used to determine the percentage of SS load reduction for six different particle sizes for both the settling device and bypass system. Essentially no load reduction was observed for particles less than 125 micrometers (μm) in diameter, and about a 90-percent reduction occurred for particle sizes greater than 250 μm in diameter. The large removal efficiencies for particle sizes greater than 250 μm in diameter were further supported by the fact that more than 80 percent of the particle sizes trapped in the sump were greater than 250 μm in diameter. These results support the claim by the manufacturer of achieving a large percentage load reduction for particle sizes greater than 250 μm in diameter.

Wisconsin

Highway-runoff quality, and treatment efficiencies of a hydrodynamic-settling device and a stormwater-filtration device in Milwaukee, Wisconsin

The treatment efficiencies of two prefabricated stormwater-treatment devices were tested at a freeway site in a high-density urban part of Milwaukee, Wisconsin. One treatment device is categorized as a hydrodynamic-settling device (HSD), which removes pollutants by sedimentation and flotation. The other treatment device is categorized as a stormwater-filtration device (SFD), which removes pollutants by filtration and sedimentation. During runoff events, flow measurements were recorded and water-quality samples were collected at the inlet and outlet of each device. Efficiency-ratio and summation-of-load (SOL) calculations were used to estimate the treatment efficiency of each device. Event-mean concentrations and loads that were decreased by passing through the HSD include total suspended solids (TSS), suspended sediment (SS), total phosphorus (TP), total copper (TCu), and total zinc (TZn). The efficiency ratios for these constituents were 42, 57, 17, 33, and 23 percent, respectively. The SOL removal rates for these constituents were 25, 49, 10, 27, and 16 percent, respectively. Event-mean concentrations and loads that increased by passing through the HSD include chloride (Cl), total dissolved solids (TDS), and dissolved zinc (DZn). The efficiency ratios for these constituents were -347, -177, and 20 percent, respectively. Four constituents—dissolved phosphorus (DP), chemical oxygen demand (COD), total polycyclic aromatic hydrocarbon (PAH), and dissolved copper (DCu)—are not included in the list of computed efficiency ratio and SOL because the variability between sampled inlet and outlet pairs were not significantly different. Event-mean concentrations and loads that decreased by passing through the SFD include TSS, SS, TP, DCu, TCu, DZn, TZn, and COD. The efficiency ratios for these constituents were 59, 90, 40, 21, 66, 23, 66, and 18, respectively. The SOLs for these constituents were 50, 89, 37, 19, 60, 20, 65, and 21, respectively. Two constituents—DP and PAH—are not included in the lists of computed efficiency ratio and SOL because the variability between sampled inlet and outlet pairs were not significantly different. Similar to the HSD, the average efficiency ratios and SOLs for TDS and Cl were negative. Flow rates, high concentrations of SS, and particle-size distributions (PSD) can affect the treatment efficacies of the two devices. Flow rates equal to or greater than the design flow rate of the HSD had minimal or negative removal efficiencies for TSS and SS loads. Similar TSS removal efficiencies were observed at the SFD, but SS was consistently removed throughout the flow regime. Removal efficiencies were high for both devices when concentrations of SS and TSS approached 200 mg/L. A small number of runoff events were analyzed for PSD; the average sand content at the HSD was 33 percent and at the SFD was 71 percent. The 71-percent sand content may reflect the 90-percent removal efficiency of SS at the SFD. Particles retained at the bottom of both devices were largely sand-size or greater.

Wisconsin

Parking lot runoff quality and treatment efficiency of a stormwater-filtration device, Madison, Wisconsin, 2005-07

To evaluate the treatment efficiency of a stormwater-filtration device (SFD) for potential use at Wisconsin Department of Transportation (WisDOT) park-and-ride facilities, a SFD was installed at an employee parking lot in downtown Madison, Wisconsin. This type of parking lot was chosen for the test site because the constituent concentrations and particle-size distributions (PSDs) were expected to be similar to those of a typical park-and-ride lot operated by WisDOT. The objective of this particular installation was to reduce loads of total suspended solids (TSS) in stormwater runoff to Lake Monona. This study also was designed to provide a range of treatment efficiencies expected for a SFD. Samples from the inlet and outlet were analyzed for 33 organic and inorganic constituents, including 18 polycyclic aromatic hydrocarbons (PAHs). Samples were also analyzed for physical properties, including PSD. Water-quality samples were collected for 51 runoff events from November 2005 to August 2007. Samples from all runoff events were analyzed for concentrations of suspended sediment (SS). Samples from 31 runoff events were analyzed for 15 constituents, samples from 15 runoff events were analyzed for PAHs, and samples from 36 events were analyzed for PSD. The treatment efficiency of the SFD was calculated using the summation of loads (SOL) and the efficiency ratio methods. Constituents for which the concentrations and (or) loads were decreased by the SFD include TSS, SS, volatile suspended solids, total phosphorous (TP), total copper, total zinc, and PAHs. The efficiency ratios for these constituents are 45, 37, 38, 55, 22, 5, and 46 percent, respectively. The SOLs for these constituents are 32, 37, 28, 36, 23, 8, and 48 percent, respectively. The SOL for chloride was -21 and the efficiency ratio was -18. Six chemical constituents or properties-dissolved phosphorus, chemical oxygen demand, dissolved zinc, total dissolved solids, dissolved chemical oxygen demand, and dissolved copper-were not included in the efficiency or SOL, because the difference between concentrations in samples from the inlet and outlet were not significant. Concentrations of TP and TSS were inexplicably high in samples at the inlet for one event.

Wisconsin

Water Quality, Hydrology, and Response to Changes in Phosphorus Loading of Nagawicka Lake, a Calcareous Lake in Waukesha County, Wisconsin

Nagawicka Lake is a 986-acre, usually mesotrophic, calcareous lake in southeastern Wisconsin. Because of concern over potential water-quality degradation of the lake associated with further development in its watershed, a study was conducted by the U.S. Geological Survey from 2002 to 2006 to describe the water quality and hydrology of the lake; quantify sources of phosphorus, including those associated with urban development; and determine the effects of past and future changes in phosphorus loading on the water quality of the lake. All major water and phosphorus sources were measured directly, and minor sources were estimated to construct detailed water and phosphorus budgets for the lake. The Bark River, near-lake surface inflow, precipitation, and ground water contributed 74, 8, 12, and 6 percent of the inflow, respectively. Water leaves the lake primarily through the Bark River outlet (88 percent) or by evaporation (11 percent). The water quality of Nagawicka Lake has improved dramatically since 1980 as a result of decreasing the historical loading of phosphorus to the lake. Total input of phosphorus to the lake was about 3,000 pounds in monitoring year (MY) 2003 and 6,700 pounds in MY 2004. The largest source of phosphorus entering the lake was the Bark River, which delivered about 56 percent of the total phosphorus input, compared with about 74 percent of the total water input. The next largest contributions were from the urbanized near-lake drainage area, which disproportionately accounted for 37 percent of the total phosphorus input but only about 5 percent of the total water input. Simulations with water-quality models within the Wisconsin Lakes Modeling Suite (WiLMS) indicated the response of Nagawicka Lake to 10 phosphorus-loading scenarios. These scenarios included historical (1970s) and current (base) years (MY 2003-04) for which lake water quality and loading were known, six scenarios with percentage increases or decreases in phosphorus loading from controllable sources relative to the base years 2003-04, and two scenarios corresponding to specific management actions. Because of the lake's calcareous character, the average simulated summer concentration of total phosphorus for Nagawicka Lake was about 2 times that measured in the lake. The models likely over-predict because they do not account for coprecipitation of phosphorus and dissolved organic matter with calcite, negligible release of phosphorus from the deep sediments, and external phosphorus loading with abnormally high amounts of nonavailable phosphorus. After adjusting the simulated results for the overestimation of the models, a 50-percent reduction in phosphorus loading resulted in an average predicted phosphorus concentration of 0.008 milligrams per liter (mg/L) (a decrease of 46 percent). With a 50-percent increase in phosphorus loading, the average predicted concentration was 0.020 mg/L (an increase of 45 percent). With the changes in land use under the assumed future full development conditions, the average summer total phosphorus concentration should remain similar to that measured in MY 2003-04 (approximately 0.014 mg/L). However, if stormwater and nonpoint controls are added to achieve a 50-percent reduction in loading from the urbanized near-lake drainage area, the average summer total phosphorus concentration should decrease from the present conditions (MY 2003-04) to 0.011 mg/L. Slightly more than a 25-percent reduction in phosphorus loading from that measured in MY 2003-04 would be required for the lake to be classified as oligotrophic.

Scientific Investigations Report

Effects of best-management practices in Otter Creek in the Sheboygan River Priority Watershed, Wisconsin, 1990-2002

The U.S. Geological Survey and the Wisconsin Department of Natural Resources began a comprehensive, multidisciplinary evaluation-monitoring program in 1989 to assess the effectiveness of the Wisconsin Nonpoint Source Program. Hydrologic, water-quality, habitat, and fish data were collected at Otter Creek from 1990 to 2002 with the pre-BMP (best-management practice) period ending in September 1993 and the post-BMP period beginning in October 1999. BMPs installed in this basin included streambank protection and fencing, stream crossings, grade stabilization, buffer strips, various barnyard-runoff controls, nutrient management, and a low degree of upland BMPs. Reductions between pre- and post-BMP periods were detected in median concentrations of base-flow samples for total suspended solids and BOD5 but not for total phosphorus or dissolved ammonia nitrogen; fecal coliform concentrations in base-flow samples increased over the study period. Reductions in rainfall storm loads between the pre- and post-BMP periods during the non-vegetative season (November through May) were detected for all three constituents monitored (total suspended solids, total phosphorus, and dissolved ammonia nitrogen). Differences in rainfall storm loads of these three constituents for the vegetative season (June through October) were not detected. When considering rainfall data from the entire year, reductions in storm loads were detected for total suspended solids and dissolved ammonia nitrogen (reductions were estimated at 58 percent for total suspended solids and 41 percent for dissolved ammonia nitrogen). Annual reductions in rainfall storm loads for the non-vegetative season were estimated at 58 percent for total suspended solids, 48 percent for total phosphorus, and 41 percent for dissolved ammonia nitrogen. Habitat and fish data were collected each year of the study to track the effects of BMPs on stream habitat and fish communities. Final trend analysis was performed using habitat quality index scores, an index of biotic integrity, and some of the originally measured fish and habitat variables. Habitat was improved for stream segments that had either natural riparian buffer or where streambank fencing was installed, but not at the station where the riparian area was pasture and no streambank fencing was installed. The results also suggest that BMP implementation in Otter Creek substantially modified fish community structure, but the overall community quality was not improved.

Wisconsin