Browsing by Author "Herb, William"
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Item Analysis of Stormwater Runoff Best Management Practices in Miller Creek, Duluth, MN(2021-01) Herb, WilliamItem Analysis of the effect of stormwater runoff volume regulations on thermal loading to the Vermillion River(St. Anthony Falls Laboratory, 2008-09) Herb, WilliamResidential and commercial development dramatically alters the surface and groundwater hydrology of watersheds. Increasing areas of impervious surfaces can lead to higher peak stream flows and reduced baseflow, which both can lead to degradation of fish habitat. In addition, thermal pollution from surface runoff is increasing recognized as an additional mechanism for fish habitat degradation in coldwater stream systems. Stormwater best management practices (BMPs) such as infiltration ponds, rain gardens, and swales are often used to reduce stormwater surface runoff rates and volumes, and to increase infiltration and groundwater recharge. Wet detention ponds used to limit runoff flow rates and reduce sediment loads are not likely to reduce thermal loading, since there is no reliable mechanism for volume or temperature reduction. Infiltration practices that capture all of smaller storms and initial portion of larger storms are very likely to significantly reduce thermal loading, since the warmest surface runoff typically happens during low volume storms and the initial portions of larger storms. To predict changes in thermal loading to streams due to land use changes, a simulation model of runoff temperature is currently being developed as part of a research project that SAFL is conducting for the Minnesota Pollution Control Agency (“Development and Implementation of a Tool to Predict and Assess the Impact of Stormwater Runoff on Trout Streams”). The current version of the tool, MINUHET (MINnesota Urban Heat Export Tool), has components for simulating runoff volume and temperature for mixed land use sub-divisions, routing of runoff flow and heat through both conventional storm sewer systems and pervious channels, and for simulating wet ponds and infiltration ponds. Thus, MINUHET has the capability to quantify the reduction in thermal loading due to the addition of infiltration practices.Item Analysis of Vermillion River Stream Flow Data (Dakota and Scott Counties, Minnesota)(St. Anthony Falls Laboratory, 2008-07) Herb, William; Stefan, HeinzAs part of an effort to characterize the response of the Vermillion River to surface runoff, the flow records from seven gaging stations were analyzed to determine the data quality, typical low flows, and the contribution of major tributaries to the total flow. The flow record from the U.S. Geological Survey gaging station at Empire appears to give the most reliable flow data and has the longest record (33 years). An effort by the Minnesota Department of Natural Resources (MNDNR) to recalibrate other Vermillion River flow gaging stations appears to have resulted in self-consistent data for 2007 flows in the main stem and at tributary stations. Although many of the stream gaging stations examined in this study have flow records of up to eight years, flow data prior to 2007 have to be used with caution. To select a representative summer low flow for a stream temperature analysis, the 33 year record at the USGS station at Empire was analyzed to determine 7Q2, and 7Q10 low flows, and monthly median and mean flows. The monthly and 7Q2 flows are representative of typical flow conditions, while the 7Q10 flow is an extreme low flow condition. Analyses were made both with and without the flow contribution of the Empire WWTP (wastewater treatment plant), to asses both pre- and post-2007 conditions. For a July/August composite average, the mean, median, 7Q2, and 7Q10 flows at the USGS station are 68.0, 43.4, 28.6, and 12.5 cfs, respectively, without the WWTP effluent.Item Application of a Runoff Temperature Model (MINUHET) to a Residential Development in Plymouth, MN(St. Anthony Falls Laboratory, 2007-06) Janke, Ben; Herb, William; Mohseni, Omid; Stefan, HeinzThe MINUHET (MINnesota Urban Heat Export Tool) model is a simulation tool used to route heat and storm water through a sub-watershed for a rainfall event or events of interest. The model includes components for developed land uses, undeveloped or vegetated land uses, pervious and impervious open channels, storm sewer systems, and storm water ponds. As a case study, the model has been applied to a 12.5 acre housing development in Plymouth, MN. The process of identifying necessary data is outlined, as well as a general strategy for organizing the input data and setting up the model for this particular watershed. A catch basin at the outlet of the development was instrumented for flow and temperature, and data were collected at the site from August 25, 2005 to October 1, 2005. The model was run for three rainfall events, and a comparison was made between observed and simulated flow rate and flow temperature at the development outlet. Overall, the model performed well. The RMSE for flow was 42.0 L/s, 10.4 L/s, and 14.3 L/s for the three events respectively, and the corresponding RMSE in storm water runoff temperature was 1.6 °C, 1.2 °C, and 1.9 °C. Observed and simulated volumeaveraged mean runoff temperature differed by less than 1.5 ºC for all three events. Total volume of runoff was predicted with reasonable accuracy by the model, especially for the first two events. Heat export, which is a measure of the heat content of the runoff above a certain reference temperature (in this case 16.0 °C), was accurately predicted for the second and third events. The model was found to be highly sensitive to saturated hydraulic conductivity and rainfall temperature (dew point temperature): volume of runoff from the pervious areas varied considerably with changes in hydraulic conductivity, and runoff temperature often tended toward dew point temperature, especially in the absence of large atmospheric or ground heat fluxes (e.g., late at night or early in the morning). This suggests that special care should be taken in selection of soil properties, and that all climate data should be collected as near to the study site as possible to improve the accuracy of runoff temperature estimation.Item Assessing Culverts in Minnesota: Fish Passage and Storm Vulnerability(Minnesota Department of Transportation, 2021-11) Kozarek, Jessica; Herb, William; Bentelspacher, NickCulverts at road-stream crossings can create barriers to movement within a stream network that can have dramatic consequences for fish populations by fragmenting habitat. Culverts can become barriers when flow conditions exceed fish swimming ability, e.g., for drop at the outlet and insufficient depth or excess flow velocity. In this project, we use a simple modeling framework to assess 50 culverts throughout Minnesota to: a) determine what fraction of these culverts currently present a fish passage barrier for both high flows (velocity barrier) and low flows (depth barrier) and b) to summarize design parameters that most affect passibility (e.g., culvert width). The estimated high and low flows are fed into the HY-8 culvert hydraulics model, and the resulting velocity and depths are compared to published fish swimming capabilities. We also assess future (2061-2080) high- and low-flow fish passage conditions for five culvert sites using global climate model outputs, Hydrologic Simulation Program Fortran (HSPF) runoff models, and the fish passibility modeling framework. Both low- and high-flow conditions in streams are very responsive to future climate, with either positive or negative future changes, depending on which global climate model is used. This study concludes that maintaining a low-flow channel or embedded culvert barrel will make culverts more passable during changes in low flows and ensuring culvert widths equal to or greater than the bankfull channel width in combination with embedded sediment will help mitigate increases in high fish passage flows and high peak flows.Item Assessing Impacts of Climate Change on Vulnerability of Brook Trout in Lake Superior’s Tributary Streams of Minnesota(University of Minnesota Duluth, 2013) Johnson, Lucinda B; Herb, William; Cai, MeijunWater temperature is generally considered one of the primary physical habitat parameter determining the suitability of stream habitat for fish species, with effects on the mortality, metabolism, growth, behavior, and reproduction of individuals. In this study we assessed the potential threats of climate change on stream temperatures and flow regimes in Lake Superior tributary streams in Minnesota, USA. The study included deterministic models for stream flow and temperature of three study streams (Amity Creek, Baptism River, Knife River), and regional (empirical) models for specific flow and temperature parameters to give better spatial coverage of the region. Information on stream flow, stream temperature, and land cover was used to develop a brook trout presence/absence model to understand the current pattern of distribution of brook trout and predict future distributions under future climate. The hydrology of north shore streams is mainly driven by air temperature and precipitation. Historical air temperatures in the region have a significant upward trend, particularly since 1980. Global climate model (GCM) outputs project a continued increasing trend in air temperature, with an increase in mean annual air temperature of 2 to 3 °C by 2089. The historical precipitation data shows an increasing trend for total annual precipitation at Duluth and Two Harbors between 1900 and 2010, whereas Grand Marais and Grand Portage do not have a clear trend. Based on an analysis of daily precipitation totals, there is some indication of an increasing trend in the number of days in summer with high precipitation (10-20 cm). Both the GENMOM and the ECHAM5 GCMs project overall increases in precipitation of about 15%, but differ with respect to the seasonal distribution of the precipitation changes. A significant and relatively certain impact of climate change is a projected shift in precipitation from snowfall to rainfall. While an increasing trend in precipitation leads to increasing streamflow, the increasing trend in spring and summer air temperature tends to reduce streamflow (by increasing evapotranspiration). Available streamflow records for north shore streams suggest there may be a decreasing trend in mean annual flow and summer low flow, but the trends are not statistically significant. Future projections of streamflow based on the GCM output were mixed, with the deterministic models projecting moderate increases in average stream flow and summer low flow, while the regression models for project a moderate decrease in low flow. Stream temperature analyses for the three study streams based on GCM climate output give the result of fairly uniform seasonal increases in stream temperature to 2089 ranging from 1.3 to 1.9 °C for the GENMOM model to 2.2 to 3.5°C for the ECHAM5 model. Application of the GENMOM climate data to the deterministic stream temperature models produced fairly similar stream temperature changes for the three study sites. The empirical stream temperature study found stream temperature in the north shore region to be influenced by air temperature, catchment size, percentage of woody wetlands, latitude, and soil permeability rate. In response to climate change projected by the GENMOM GCM, the regional stream temperature model projects July mean water temperature to rapidly increase by approximately 1.2oC from 1990s to 2060s, followed by a slight decrease to 2089. The temperature increase was predicted to be the largest in the coastal area of middle north shore region. The brook trout presence/absence model found water temperature to have the strongest influence on trout presence. Brook trout were predicted to be at risk for water temperatures above 18.7oC and be extirpated from streams for temperatures over 20oC. Stream flow was shown to have a negative effect on trout presence, though not as strong as water temperature. Overall, these data predict that brook trout may be extirpated from lower shore area, be exposed to increasing risk in middle shore region, and remain present in upper shore streams from the present to 2089. This work would benefit greatly from a number of modifications to the GCM’s, the spatial data used in the development of both the deterministic and empirical models, and implementation of a more detailed, spatially explicit, hydrologic model. Finally, additional fish data, including cool and warm water assemblage data, along with descriptors of landscape structure (i.e., connectivity) would allow us to assess the areas where cold water species may be threatened by the presence or potential presence of coolwater competitors.Item BROWN’S CREEK THERMAL STUDY(2016-04) Herb, William; Correll, CamillaItem Data for "A Field Study of Maximum Wave Height, Total Wave Energy, and Maximum Wave Power Produced by Four Recreational Boats on a Freshwater Lake"(2022-01-27) Marr, Jeffrey; Riesgraf, Andrew; Herb, William; Lueker, Matthew; Kozarek, Jessica; Hill, Kimberly; marrx003@umn.edu; Marr, Jeffrey; St. Anthony Falls LaboratoryPlease see related report.Item Detailed Hydrology for Stormwater BMPs(2020-03) Herb, William; Johnson, Lucinda; Gulliver, JohnItem Determination of Optimum Time for the Application of Surface Treatments to Asphalt Concrete Pavements - Phase II(Minnesota Department of Transportation, 2008-06) Marasteanu, Mihai; Velasquez, Raul; Herb, William; Tweet, John; Turos, Mugur; Watson, Mark; Stefan, Heinz G.Significant resources can be saved if reactive type of maintenance activities are replaced by proactive activities that could significantly extend the pavements service lives. Due to the complexity and the multitude of factors affecting the pavement deterioration process, the current guidelines for applying various maintenance treatments are based on empirical observations of the pavement surface condition with time. This report presents the results of a comprehensive research effort to identify the optimum timing of surface treatment applications by providing a better understanding of the fundamental mechanisms that control the deterioration process of asphalt pavements. Both traditional and nontraditional pavement material characterization methods were carried out. The nontraditional methods consisted of X-Ray Photoelectron Spectroscopy (XPS) for quantifying aging, while for microcracks detection, electron microprobe imaging test (SEM) and fluorescent dyes for inspection of cracking were investigated. A new promising area, the spectral analysis of asphalt pavements to determine aging, was also presented. Traditional methods, such as Bending Beam Rheometer (BBR), Direct Tension (DTT), Dynamic Shear Rheometer (DSR) and Fourier Transform Infrared Spectroscopy (FTIR) for asphalt binders and BBR and Semi-Circular Bending (SCB) for mixtures were used to determine the properties of the field samples studied in this effort. In addition, a substantial analysis of measured pavement temperature data from MnROAD and simulations of pavement temperature using a one-dimensional finite difference heat transfer model were performed.Item Environmental Impacts of Potassium Acetate as a Road Salt Alternative (University of Minnesota evaluation)(Minnesota Department of Transportation, 2022-07) Gulliver, John S.; Chun, Chan Lan; Weiss, Peter T.; Erickson, Andrew J.; Herb, William; Henneck, Jerry; Cassidy, KathrynRoad salt (NaCl) is used predominantly across the state for winter road anti-icing (as brine) and de-icing (as a solid) operations. Road salt is used because it is inexpensive and effective, but the thousands of tons used annually have resulted in increasing chloride concentrations of surface water bodies throughout Minnesota. In many cases, chloride concentrations are above regulatory limits, which results in the loss of aquatic biota and the water body being labeled as impaired. Thus, there is a need for one or more road salt alternatives (RSAs) that are effective, relatively inexpensive, and environmentally friendly. This report investigates the environmental impacts of potassium acetate (Kac), which is effective at lower temperatures than most other potential RSAs and is also less corrosive to steel than conventional road salt. Field measurements indicate that current applications of KAc do not have a substantial influence on biochemical oxygen demand (BOD) and microbiological water quality in Lake Superior. However, KAc concentrations due to application to 25% of the roads in the Miller Creek watershed are predicted to be above the toxic limit for water fleas. We believe that KAc could be used in the most precarious winter driving safety locations, but not over all watershed roads or for all storms. Acetate could be used as a general organic anti-icer, but in combination with another cation, such as sodium or magnesium.Item An Experimental and Numerical Study of Long-throated Flumes(2020-11) Herb, William; Hernick, MatthewItem A Field Study of Maximum Wave Height, Total Wave Energy, and Maximum Wave Power Produced by Four Recreational Boats on a Freshwater Lake(2022-02-01) Marr, Jeffrey; Riesgraf, Andrew; Herb, William; Lueker, Matthew; Kozarek, Jessica; Hill, KimberlyItem A flow and temperature model for the Vermillion River, Part I: Model development and baseflow conditions(St. Anthony Falls Laboratory, 2008-08) Herb, William; Stefan, HeinzStream temperature and stream flow are important physical parameters for aquatic habitat preservation in river and stream systems. Water temperature is particularly important for coldwater stream systems that support trout. Summer base flow conditions with low flows and high water temperatures can be critical for maintaining trout habitat. Surface runoff from rainfall events can lead to increases in stream temperature, particularly in developed watersheds. To better understand the interactions between stream temperature, land use, and climate, an unsteady stream flow and temperature model has been developed for the Vermillion River. The model includes the main stem from Dodd Avenue to Goodwin Avenue and a number of tributaries, including South Branch, South Creek, North Creek, and Middle Creek. The EPDriv1 package was used to simulate stream flow, including distributed groundwater inputs. Simplified stream channel geometry was required to obtain converged flow solutions for unsteady low flows. A stream temperature model has been assembled based on previous work at SAFL. The stream temperature model uses flow and flow area from the flow solver, along with observed climate data to calculate surface heat transfer. Groundwater inflows are an important component of both the flow and temperature model. For the Vermillion River, groundwater inflow rates were estimated from flow gaging sites, while groundwater temperatures were estimated by calibrating the stream temperature model. The calibrated combination of groundwater flow and temperature results in a good match of simulated and observed stream temperature, with RMSEs in the range of 0.75 to 2 ºC. The assembled flow and temperature model for the Vermillion River has been calibrated for baseflow conditions, and provides a starting point for future analysis of surface runoff inputs during rainfall events.Item Heat Export and Runoff Temperature Analysis for Rainfall Event Selection(St. Anthony Falls Laboratory, 2007-04) Herb, William; Mohseni, Omid; Stefan, HeinzThermal pollution by surface runoff from urban areas can contribute to the degradation of coldwater ecosystems. The hydrothermal characteristics of surface runoff from rainfall are therefore of interest. Three hydrothermal parameters of surface runoff have been studied: runoff temperature (oC), heat flux (W/m2) and total heat export (J/m2). Heat fluxes were defined above a reference temperature of 20oC. The results can be used to identify storm events that have the potential for the largest heat export from a watershed and consequently the strongest thermal pollution of a receiving coldwater stream. In this study, records of rainfall events and weather data are used to estimate the three hydrothermal parameters by model simulation. The model for predicting rainfall runoff temperatures and rates from an impervious surface (parking lot) has been described in Project Report No. 484 from the St. Anthony Falls Laboratory, University of Minnesota (Herb et al 2006). The weather data came from the MnROAD test site in Albertville, MN, and from the SAMSON data set. Runoff temperatures and heat export were calculated for a 100x100m paved surface using 6 years of 15 minute weather data or 30 years of 1-hour weather data. The 6-year data set contained 280 rainfall events from April through October. The 280 values of the three hydrothermal parameters were related to basic rainfall event parameters such as total rainfall, duration, and rainfall temperature (dew point). Average runoff temperature was found to be well correlated to dew point temperature during the storm, and air temperature and solar radiation prior to the storm. 20 extreme values of the hydrothermal parameters were ranked and also related to basic rainfall parameters. Partial duration series of hydrothermal parameters were analyzed separately for frequency of occurrence (return periods).Item Lake of the Woods Shoreline Erosion: Analysis of Historical Shorelines, Climate and Lake Level(St. Anthony Falls Laboratory, 2005-03) Herb, William; Mohseni, Omid; Stefan, HeinzThis report summarizes the results of Phase I of a study of erosion of the Minnesota shoreline of Lake of the Woods. The overall objectives of this study are (a) to determine the causes and to estimate the magnitude of the shoreline recession rates in the US shorelines of Lake of the Woods, and (b) to recommend management practices for shoreline protection against erosion. In Phase I, we collected historical data on wind and water levels at Lake of the Woods, flow and suspended sediment input from the Rainy River, and information on the shoreline, including aerial photos, satellite images, and soil surveys. Analyses of aerial photos from 1940 to 2003 show rapid erosion of several undeveloped wetland areas of the shoreline and relatively slow erosion of developed areas along Sandy Shores and Birch Beach. Analysis of Pine and Sable Islands show a combination of erosion, rebuilding, and shifting from 1940 to 2003, so that the present state of the islands may represent either a long term loss or a loss/rebuilding cycle. Since long term wind records for Lake of the Woods were not found, a synthetic wind record was constructed from regional wind records. Analysis of wind and water level data from the 1950’s to the present show a relatively uniform distribution of high wind and high water events. Recent high water events appear as typical events that take place several times per decade. Wind and wave data were also collected at two locations on the southern side of Big Traverse Bay, with record lengths of 4 – 5 weeks. The on-lake wind data and wave data will be useful to calibrate wave models in Phase II, and have been used in Phase I to correlate on-lake wind with local and regional off-lake wind measurements. Field measurements of near-shore bathymetry were made and sediment samples were collected to determine size distribution were also collected in preparation for Phase II. Preliminary analyses of data for the Rainy and the Little Fork rivers do not show distinct trends in flow rate or suspended sediment concentration for the period of record.Item Maps of wind-wave height on Minnesota lake shorelines(2022-01-27) Herb, William; Janke, Ben; Cai, Meijun; Stefan, Heinz; Johnson, Lucinda; herb0003@umn.edu; Herb, William; University of Minnesota St. Anthony Falls Lab; University of Minnesota Duluth Natural Resources Research InstituteThis data set provides maps of typical wind-wave height and energy on Minnesota lakes to inform shoreline and near-shore habitat restoration projects. The data set consists of a set of ArcMap shape files which map out simulated wave height and energy parameters for a series of points around the shoreline of 460 lakes in Minnesota, with separate files for annual wave statistics and monthly wave statistics. The wave statistics were calculated for each lake based on airport wind data and the open water distance (fetch) across the lake for each wind direction. Each shapefile contains information on multiple wave statistics, including the mean and significant wave height, the number of days wave height exceeds thresholds, and cumulative wave energy over the time period.Item MCPLANT: A Simulation Model of Dissolved Oxygen Production by Aquatic Macrophytes(St. Anthony Falls Laboratory, 2000-08) Salomone, Matthew D.; Herb, William; Mohseni, Omid; Stefan, Heinz G.A one-dimensional water column model is constructed to simulate dissolved oxygen dynamics in a shallow lake populated with submersed macrophyte vegetation. The MCPLANT (Modeled C++ Plant Layers Approximating Natural Theory) model constitutes a macrophyte growth model concomitant with a kinetic description of processes involved in producing and consuming dissolved oxygen. Photosynthetic production of dissolved oxygen by macrophytes is considered as a principal source in the water column; respiration and decay are principal sinks of dissolved oxygen. Environmental data and lake trophic status are principal inputs to the model.Item MINUHET (Minnesota Urban Heat Export Tool) USER MANUAL(St. Anthony Falls Laboratory, 2010-01) Herb, William; Janke, Ben; Mohseni, Omid; Stefan, HeinzMINUHET (Minnesota Urban Heat Export Tool) is a tool used to simulate the flow of stormwater surface runoff and its associated heat content through a small watershed for a rainfall event or events of interest. The main output of MINUHET is a time series of flow rate and temperature at the outlet of the watershed, to enable prediction of thermal impact on receiving streams. MINUHET is event-based, i.e. it is designed primarily to simulate a single storm event. The MINUHET tool includes a database of observed and/or synthetic storm events that have the potential to produce high thermal loading in receiving streams.Item A Model for Mitigation of Surface Runoff Temperatures by a Wetland Basin and a Wetland Complex(St. Anthony Falls Laboratory, 2007-07) Herb, William; Mohseni, Omid; Stefan, HeinzThis report describes hydro-thermal models developed to simulate temperature mitigation of surface runoff for wetland basins. Two models are described: 1) a dead zone model, which is a modification of the previously developed vegetated pond model to include flow short circuiting and 2) a new, multi-cell model that attempts to model lateral temperature gradients between a short-circuiting channel and a wetland basin. Both models predict that a well-vegetated wetland basin can provide substantial thermal mitigation. The dead zone model is used in conjunction with a model for a wet pond to simulate the response of a wetland complex to stormwater inflow for 6 years of observed storm events. The wetland complex was found to reduce runoff temperature by 2.6 °C, on average for Minnesota climate conditions, compared to unmitigated runoff from an asphalt parking lot. The wetland complex did not, however, reduce the average runoff temperature for all storms. During very warm weather following storm events, the wetland outflow temperature did exceed 20 °C for periods of up to several days.