Concurrent Session VI, Track A: Redevelopment Green Infrastructure

1085: Brownfield to Headwaters: Comprehensive District Stormwater Analysis and Planning for the Highland Bridge

Author(s): Bob Fossum, Capitol Region Watershed District; Nathan Campeau, PE, Barr Engineering Co.

Description: Redevelopment on Ford's former Twin Cities Assembly Plant in Saint Paul has begun on 122 acres of land situated along the Mississippi River. For more than 15 years, the City’s vision for the site has been that it will be a livable, sustainable mixed-use neighborhood that looks to the future with clean technologies and high-quality design for energy, buildings and infrastructure.

Capitol Region Watershed District and the City of Saint Paul, with Barr Engineering’s assistance, developed a stormwater management vision for the Ford Site that is the backbone of the development. A comparative analysis was completed to compare redevelopment public realm and stormwater management alternatives. A centralized stormwater management approach was compared to a baseline parcel-by-parcel approach. Innovative approaches/tools for comparing feasibility costs, benefits, impacts and sustainability profiles for the different options provided valuable insights about the community value that redevelopment alternatives might generate. A key component of the proposed analysis was monetization of ALL the costs and benefits of each scenario, which demonstrated that a centralized stormwater management approach resulted in 2.5 times the benefits for approximately the same cost. The benefits of layered or stacked function of public space allowed for wide-ranging support of the centralized stormwater approach. This was especially important with high land value and redevelopment cost at the Brownfield site inSaint Paul. The analysis provided the technical support to establish the City’s new Green Infrastructure Overlay District and the financing mechanisms to construct, operate and maintain the stormwater system.

1071: Brownfield to Headwaters: Implementation of the Highland Bridge District Stormwater System

Author(s): Nathan Campeau, Barr Engineering Co.; Bob Fossum, Capitol Region Watershed District

Description: Responding to the closure of the Ford Twin Cities Assembly Plant in Saint Paul, the Capitol Region Watershed District (CRWD) and the City of Saint Paul, with the assistance of Barr Engineering, developed a sustainable stormwater feasibility plan for redeveloping the 122-acre property along the Mississippi River. In 2018, the property was sold to a local developer, Ryan Companies, and work began to design and construct the district stormwater vision as part of the Highland Bridge development.

Construction of the $13M stormwater infrastructure began in 2020 and was completed in 2022. The constructed BMPs include five large biofiltration basins that use iron-enhanced sand filters to remove dissolved phosphorus, five underground storage and filtration systems that target nutrient loading, two large rate-control ponds, and a reimagined Hidden Falls Creek. The project reduces total suspended solids by 94%, total phosphorus by 75%, and peak discharges to the downstream waterfall and stream channel by 98% in the two-year event. The project also includes approximately 1/2-mile of pedestrian connections that provide access through the site and to the Mississippi River.

This talk will provide an overview of the design, construction process including an innovative approach to construction stormwater bypassing, as well as lessons learned from phasing and operations and maintenance of a stormwater system that had to be completed before any development was constructed. The talk will also highlight how Ryan Companies, the City, and CRWD approached and incorporated public art throughout the site to celebrate the site’s history and connection to water.

1013: Connected Habitat, Public Places, and Surface Stormwater at Minneapolis’s Upper Harbor

Author(s): Daniel Kalmon, Mississippi Watershed Management Organization; Nathan Campeau, Barr Engineering

Description: The 2015 closing of the Minneapolis Upper Harbor Terminal (UHT) opened up 52 acres of prime riverfront and an extensive planning and design effort between residents in North Minneapolis, the City, the Minneapolis Park and Recreation Board (MPRB), the Developers, and the Mississippi Watershed Management Organization (MWMO), to reconnect the community to the river. In 2019 The City adopted the UHT Core Concept Plan which signaled a willingness to work with the MWMO and Barr Engineering on the design of an Upper Harbor District System, to include stormwater management, habitat, and public realm enhancements.

Throughout the project, the MWMO has focused all of its design, engineering, and legal efforts on outcomes that surpass regulations and result in an integrated system of habitat, public places, and surface stormwater (HPS) that supports a living ephemeral stream. In addition, the 15.2-acre footprint of the combined Upper Harbor District System and shoreline restoration is connected with trails and habitat corridors throughout the 52-acre site, to the Mississippi River, and back into the neighborhood. These efforts will significantly increase social, economic, and environmental benefits to a Minneapolis Green Zone community that historically has been disconnected from the benefits of the Mississippi River and other natural systems.

This presentation will shed light on the extensive planning, design, legal, and engineering work that led up to the implementation of the first phase of construction in 2022 (one mile of restored shoreline along the Mississippi River), current capital projects underway, future construction phases, and performance of the system overall.

1110: BMP Mosaic, Meeting Standards with Multiple BMP Types and Reuse

Author(s): Adam Tjaden, Kimley Horn

Description: How do you meet two watershed sets of rules on a 20-acre site with significant site constraints and a mix of public and private development? In addition to navigating the site layout, additional challenges included predominantly clayey fill soils, and groundwater constraints. The site utilized a number of BMP designs in order to meet the regulatory criteria including, sedimentation pond with iron enhanced filtration bench, two surface filtration basins, and an underground filtration basin. Additionally, the proposed multifamily building will harvest and treat rainwater for use in toilet flushing throughout the building. The stormwater management and public improvements were completed in 2022. Construction of the medical office building is ongoing, and the multifamily building is planned to be completed in 2023.

The Dundee Nursery site in Plymouth, MN has long been discussed as a potential redevelopment site but has faced numerous obstacles in its time. One of those obstacles includes stormwater management. In 2022, the design for the redevelopment of the approximately 20 acre Dundee Nursery site was completed. The redevelopment includes proposed multifamily and medical office buildings, new public frontage road, reconstruction of the adjacent Plymouth Presbyterian Church parking lot, and associated trails, parking, and stormwater BMPs. The site happens to be located within both Bassett Creek Watershed and the Minnehaha Creek Watershed. Given the regulatory boundary dividing the site, providing a site design that met each watershed’s requirements within their respective portions of the site proved to be a unique challenge.

The presentation will focus on the site challenges and how the mix of BMPs was selected to meet the site requirements. The presentation will also show construction photos of the BMPs completed in 2022 and how they have functioned after one full growing season.

Concurrent Session VI, Track B: Wetland Tools, Critical Peatlands, and New and Historic Impacts of Invasive Species on Aquatic Ecosystems

1033: Minnesota’s Peatlands—A Hidden Storehouse of Clean Water, Carbon and Critical Habitat

Author(s): Suzanne Rhees, Minnesota Board of Water and Soil Resources; Kristen Blann, The Nature Conservancy; Chris Lenhart, University of Minnesota and TNC

Description: Minnesota is home to approximately 7 million acres of peatlands—the largest acreage in the lower 48 states. These bogs and fens are attracting increasing interest from researchers and policy-makers due to their critical importance in sequestering carbon. However, extensive ditching and draining of these peatlands threaten to turn them into sources, rather than sinks, of greenhouse gases. Based on current estimates, as much as 900,000 acres of peatland are currently drained, and about half of those acres are farmed or developed. Minnesota’s Climate Action Framework recognizes the importance of protecting and restoring this resource.

BWSR staff have been working closely with scientists and analysts at The Nature Conservancy to assess the extent and condition of these peatlands, and are currently developing criteria for peatlands-focused wetland easements. BWSR also works with public and private partners to develop large peatland restorations for wetland mitigation. We have developed an interactive web-based peatland identification tool, and are currently refining it to capture more drained and farmed histosols in Southern Minnesota. Many other agencies and institutions are involved with various facets of peatlands research, policy development and restoration. A two-day Peatlands Science Symposium was convened by the Nature Conservancy in March 2023 to share this work. This proposed session will include summaries of selected topics covered at the Symposium, updated to reflect more recent progress. Topics will include legal and policy issues, management of public and trust lands, GIS-based tools, hydrology and soil assessments, water quality issue, including mercury fluxes, and best practices for restoration.

1103: The Wetland Restoration Effectiveness Tool (WRET) for Predicting Nutrient Removal and Carbon Storage in Wetlands

Author(s): Christian Lenhart, University of Minnesota and The Nature Conservancy; Anna Kottkamp, The Nature Conservancy; Laura Bender, University of Minnesota; John Riens, US Fish & Wildlife Service

Description: This coarse-scale planning tool uses existing data on land-use, soil properties, and wetland and watershed relationships as well as other equations to estimate phosphorus and nitrogen removal as well as carbon storage and accumulation to prioritize wetlands for protection and restoration. A risk rating for dissolved phosphorus loss was developed as well. The intended use for this tool is in estimating and comparing wetland nutrient removal benefits for site prioritization, project reporting, or grant application. It is not intended for research or where precise nutrient removal estimates are required. It has been used to assess the water quality benefits on over 50 wetlands, primarily in central Minnesota. Findings indicate that wetlands are not usually placed to optimize nutrient removal. Predicted removal for nitrogen was high, at 38-100%, although most wetlands were treating small drainage areas, less than 100 acres, so the total load removed was not large. Predicted total phosphorus removal rates were lower than nitrogen and dissolved phosphorus loss risk was moderate to high in many wetlands. Overall, the tool has been useful for planning and has been adopted by the Minnesota Board of Water and Soil Resources (BWSR) on their calculators and tools website. Several organizations, including the USFWS, TNC and local governments are using it for wetland planning and high-level evaluation of their performance. The goal is often to increase the ecosystem benefits of wetlands restored mostly with plant community or wildlife goals in mind. The tool is being modified to improve its accuracy and usefulness.

1017: A Historic Look: Zebra Mussel-Induced Mercury Concentration Increases In Minnesota Fish

Author(s): Denver Link, University of Minnesota; Gretchen Hansen, University of Minnesota

Description: Regulation of mercury (Hg) emissions has led to a reduction of Hg deposition, but biological responses have been more variable. In fact, fish tissue mercury has increased as deposition has declined in lakes throughout the Midwestern United States. Zebra mussels (Dreissena polymorpha), an aquatic invasive species, reconfigure aquatic food webs and redirect energy resources from the water column to the littoral zone. Methylmercury (MeHg), the most bioavailable form of Hg, enters the aquatic food web in the nearshore regions. Recent work from the Great Lakes and inland lakes in Minnesota has documented increased total mercury concentrations in fish associated with zebra mussel invasion. However, it is unclear how widespread these impacts are. In this study, we analyze statewide total mercury data of fish collected by the state of Minnesota from 1997-2021 to assess the impacts of zebra mussels on fish mercury concentrations. We use hierarchical Bayesian models to quantify drivers of fish tissue Hg concentrations in northern pike (Esox Lucius) and walleye (Sander vitreus). Northern pike and walleye of average length from zebra mussel lakes contained more mercury than lakes uninvaded with zebra mussels when accounting for length, year, and lake effects. Fish from zebra mussel-invaded lakes also cross the Minnesota Department of Health threshold for safe eating at shorter lengths, increasing potential risk of angler harvest of these fish. This research provides insights into variability of response in aquatic systems to Hg emission regulation while also highlighting potential public health concerns with zebra mussel invasion.

1060: A New Aquatic Invasive in Minnesota: The Diatom Didymosphenia Along Lake Superior’s North Shore

Author(s): David Burge, Science Museum of Minnesota: St. Croix Watershed Research Station; Mark Edlund, Science Museum of Minnesota: St. Croix Watershed Research Station; Heidi Rantala, Minnesota Department of Natural Resources; Robert Pilsbury, University of Wisconsin Oshkosh: Department of Biology and Microbiology; Sarah Clauss, University of Minnesota-Duluth: Large Lakes Observatory; Cody Sheik, University of Minnesota-Duluth: Large Lakes Observatory; Cory Goldsworth, Minnesota Department of Natural Resources; Nicholas Peterson, Minnesota Department of Natural Resources; Adam Heathcoate, Science Museum of Minnesota: St. Croix Watershed Research Station

Description: In 2018, the nuisance diatom, Didymosphenia geminata (aka didymo, rocksnot), appeared in the Poplar River along Lake Superior’s North Shore. Although native to nearshore Lake Superior, nuisance didymo blooms have appeared in cool-water streams throughout North America and globally to threaten stream ecology, recreational opportunities, and regional economies dependent on healthy streams and fisheries. In streams, didymo forms thick mucilaginous growths that coat all hard substrates in centimeters-thick goo. Since 2021 we have been monitoring streams and nearby lake sites along Minnesota’s North Shore to understand the distribution of didymo, its seasonality, environmental drivers, and its effect on stream and lake ecology. Ongoing molecular studies are investigating the potential source of didymo on the North Shore as well as how didymo mats affect bacterial and algal diversity and functioning in nutrient dynamics. To date, didymo has been recorded in eight North Shore streams including multiple streams each year with severe didymo infestations. Didymo becomes more abundant in streams during late summer/early fall and seems to thrive under long-term baseflow conditions, low nutrients, and in open canopy stream segments. Efforts are underway to expand our sampling to broader longitudinal surveys, evaluate didymo effects on stream benthos and fishes, and to promote efforts to control the spread of this new aquatic invasive species in Minnesota.

Concurrent Session VI, Track C: Water Quality: Implications for Drinking Water and Rivers

1050: Drinking Water Governance in Minnesota: Key Lessons from an In-Depth Assessment

Author(s): Lila Franklin, Freshwater; Eileen Kirby, Freshwater; Kris Meyer, Freshwater; Peter Calow, University of Minnesota; Marcelle Lewandowski, University of Minnesota Water Resources Center

Description: "Drinking water governance" refers to the systems and mechanisms of accountability operating in Minnesota to deliver and regulate drinking water. It includes the organizations and individuals within federal, state, and local government agencies; water supply utilities; water users; plus the institutions and individuals involved in land management related to protecting drinking water sources. Governance includes formal and informal power, influence, communication, and collaboration. This study, led by Freshwater on behalf of the University of Minnesota, used the Governance Assessment Framework presented in the 2020 Future of Drinking Water report (U of MN Water Resources Center) to guide in-depth group assessments of the characteristics, strengths, and weaknesses of drinking water governance in Minnesota. In May 2023, we facilitated ten, half-day focus group meetings with representatives from different levels of drinking water governance, in particular, state agencies, local land management agencies, private well owners and installers, and water supply utility managers. The assessment addressed the effectiveness of policy and implementation, coherence of policy horizontally and vertically across administrative and economic sectors, adequacy of professional capacity, data availability, financial constraints and equity, and the overall integrity, transparency and equity of drinking water governance. Results of the discussions will be presented. We will revise this abstract to include key lessons.

1046: Safe Drinking Water for Everyone, Everywhere in Minnesota

Author(s): Tannie Eshenaur, Minnesota Department of Health; Frieda von Qualen, Minnesota Department of Health

Description: Safe drinking water is essential to healthy families and communities. John Snow’s research on sanitation and water drove a public health focus on safe drinking water. The 1974 Safe Drinking Water Act (SDWA) protects public health by regulating public drinking water supplies. Starting in 1974, the Minnesota Well Code, regulates where and how a well is constructed and how it is sealed to protect public health and groundwater. While our ancestors laid a strong foundation for safe drinking water, there is more to do.

New contaminants, expanded health effects knowledge, aging infrastructure, and workforce shortages threaten the safety of Minnesota’s drinking water. Additionally, the 1.2 million Minnesotans who drink from private wells have inequitable protections when it comes to regular well testing and mitigation.
The "Minnesota Drinking Water Plan" focuses on actionable strategies and policies that will ensure drinking water is safe for everyone everywhere in Minnesota. The ten-year Plan identifies and addresses technological, behavioral, economic, and social factors that threaten drinking water and identifies how Minnesota can protect drinking water.

Through attending this session, participants will learn about key issues threatening drinking water in Minnesota and will receive an overview of the first version of the Plan, how the plan was developed, and how participants can help refine the Plan.

1108: Long-Term Changes in the Magnitude and Timing of Nutrient Loads in the Upper Mississippi River

Author(s): Kathi Jo Jankowski, USGS

Description: The Upper Mississippi River (UMR) provides innumerable ecological, economic, and cultural benefits for the communities of the Upper Midwest. Agricultural and urban development within the basin have had major impacts on the water quality of the river, however, and many efforts have focused on reducing delivery of nutrients and sediments locally and to the Gulf of Mexico. Whether these efforts have had notable effects on nutrient loads and concentrations throughout the basin is a matter of ongoing management interest. Therefore, using data collected by the Upper Mississippi River Restoration program’s Long Term Resource Monitoring element from six mainstem reaches and ten tributaries of the UMR from Minnesota to Missouri, we assessed whether there have been changes in the magnitude and timing of total nitrogen (TN), total phosphorus (TP), and total suspended solids (TSS) from 1994–2019. We found significant declines in TSS in tributaries and mainstem reaches throughout the basin, indicating potential basin-wide improvements in sediment loads. TP declined significantly in nearly all mainstem reaches, but tributaries showed variable trends. There was less change in TN across the basin, with the majority of sites increasing or not changing. Finally, the timing of change varied across the basin, but often trends were greatest during fall and winter. These findings indicate that while there have been notable improvements in water quality, the UMR faces ongoing challenges with nutrients. In addition, better understanding how the timing of those loads are changing will be important for better understanding and managing the river.

1079: Assessing the English Coulee to Balance Water Quality and Flood Protection

Author(s): Luke M. LaMoore, AE2S; Linda Severson, AE2S

Description: The English Coulee runs through the heart of Grand Forks, North Dakota and serves a watershed of over 80 square miles, mostly composed of agricultural land use with some urban development. The Coulee is plagued by poor water quality which impacts aesthetics and recreational value of the waterbody. During summer months residents frequently report stagnant water and foul odors associated with the Coulee. In response to community concerns, the City began their own multiphase initiative to renew the Coulee. The goal of this presentation is to highlight the key conclusions of the first phase of the project and emphasize that there doesn’t have to be a sacrifice when it comes to hydraulics and water quality in the same system.

Although the City’s study is focusing on improving water quality, it also has to ensure that changes to the English Coulee do not adversely impact the existing flood protection infrastructure regulated by both FEMA and the Army Corps of Engineer. This infrastructure was built in response to the 1997 floods, and includes an extensive levee system along the Red River and creation of the English Coulee Diversion to route flood waters around the City during large flood events.

The City is finishing the first phase of the English Coulee Renewal project this spring with the remaining phases to follow. The first phase of the project took place between 2021 and 2023 and focused on determining the causes and sources of the poor water quality and developing a baseline hydrologic and hydraulic model of the watershed to establish baseline conditions from which to compare future alternatives to, as the current FEMA model did not match observed water levels. Future phases of the project will include improvement visioning, concept refinement and finally funding plan analysis and implementation.

Concurrent Session VI, Track D: Innovative Monitoring Approaches

1100: A Novel Suspended-Sediment Sampling Method: Depth-Integrated Grab (DIG)

Author(s): Joel Groten, US Geological Survey; Sara Levin, US Geological Survey; Erin Coenen, US Geological Survey; J. William Lund, US Geological Survey; Gregory Johnson, Minnesota Pollution Control Agency

Description: Measuring suspended sediment in fluvial systems is critical to understanding and managing water resources. Sampling suspended sediment has been the primary means of understanding fluvial suspended sediment. Isokinetic and depth-integrating samplers designed and tested by the Federal Interagency Sedimentation Project (FISP), and sampling and laboratory methods developed by the US Geological Survey (USGS) are more accurate than more commonly used grab sampling and total suspended solids (TSS) laboratory methods but are not more widely used because they are expensive, time consuming, and not required as part of water quality standards in the United States. The USGS developed a new suspended-sediment sampling method called a Depth-Integrated Grab (DIG) by combining elements of both grab and USGS depth-integrating and equal width or discharge increments (EWDI) sampling methods and suspended-sediment concentration (SSC) laboratory methods. The goal of the DIG method was to provide more accurate results than grab-TSS while being easier and cheaper to sample than specialized samplers and methods. Approximately 50 comparison samples of EWDI-SSC, DIG-SSC, and Grab-TSS were collected at nine sites in Minnesota from 2018 through 2019. Results showed there was not a significant difference between the DIG and USGS sampling methods and was more accurate than the grab-TSS method. The DIG-SSC provides a more accurate alternative than the grab-TSS method and is cost effective and markedly easier to sample suspended sediment than with FISP samplers and USGS sampling methods.

1092: Satellite-Derived Water Quality Data from an Automated High-Performance Computing Environment for 10,000+ Minnesota Lakes

Author(s): Leif Olmanson, University of Minnesota; David Porter, Minnesota Supercomputing Institute, University of Minnesota; Peter Wiringa, U-Spatial, University of Minnesota

Description: Recent advances in satellite technology (improved spatial, spectral, radiometric, and temporal resolution) and atmospheric correction, along with cloud detection and supercomputing capabilities, have enabled the development of automated regional-scale measurements of water quality. These new capabilities provide opportunities to inform society and improve lake and fisheries management by more frequently measuring more variables (chlorophyll, colored dissolved organic matter (CDOM), and total suspended matter, the main determinants of water clarity) than is feasible using field methods. Utilizing these capabilities, we have created a water quality database for 10,000+ lakes in Minnesota for 2017-2022. This database includes over one million measurements of chlorophyll, clarity, and CDOM (3,000,000+ total). To make the data accessible it was used in an online map viewer linked (The Minnesota LakeBrowser ( to a spatial database that allows for statistical summaries at different delineations and time windows, temporal analysis, and visualization of water quality variables.

Having the whole population allows for unbiased geospatial and temporal analysis. By combining these data with earlier assessments, we created a 37-year (1985-2022) satellite-derived late summer water clarity database for exploring long-term trends. Changes in water clarity were attributed to changes in land use and climatic factors which will be discussed. The Minnesota DNR uses the data for the Watershed Health Assessment Framework (WHAF) to identify opportunities to improve the health and resilience of Minnesota’s watersheds and GEMS is linking the data to agricultural BMPs for the Minnesota Department of Agriculture to ascertain their effectiveness to improve the water quality of Minnesota lakes.

1101: Iron-Enhanced Sand Filter Monitoring and Assessment Challenges

Author(s): Sarah Wein, Capitol Region Watershed District; Bob Fossum, Capitol Region Watershed District

Description: Since 2011, Capitol Region Watershed District (CRWD) has monitored 4 different iron enhanced sand filter (IESF) bench projects on ponds to measure their performance as part of either new stormwater pond construction or a pond retrofit/improvement project. IESF benches are included as part of a pond project design to remove dissolved phosphorus via surface sorption to oxidized iron, and are usually situated upstream of water bodies such as lakes to reduce loading to the downstream water body. While IESF benches have been shown to reduce dissolved phosphorus loads leaving ponds, our work has shown that they present unique challenges in their monitoring and assessment.
IESF pond projects often have constraints to monitoring such as already established elevations of the main pond outlet pipes, points of access for monitoring, and the timing of collecting samples. Even when monitoring is included as part of the project design to reduce difficulties in monitoring, the assumed or projected drawdown times and flow through the filters can be very different from actual performance of the system after project completion. Additionally, after data has been collected, determining the best assessment metrics can be difficult. When measured influent values of dissolved phosphorus are close to the reporting limit and are compared to measured effluent values, percent removal metrics can show either very low removal efficiencies, or even export of dissolved phosphorus. Improved methods of monitoring and assessment of IESF bench projects will be suggested and reviewed in this talk.

1094: Low-Cost Diagnostic Monitoring: A Water Quality Improvement Project Targeting Tool

Author(s): Blayne Eineichner, Comfort Lake Forest Lake Watershed District

Description: Diagnostic monitoring is a key tool in targeting water quality improvement projects and expediting the achievement of basin wide nutrient reduction goals. Some consider it as cost prohibitive and impractical. However, when viewed as a “Water Quality Investment” it is a powerful cost-effective tool in targeting the few water quality improvement projects that are needed to reduce the majority of nutrient loading into a water resource. The initial investment in diagnostic monitoring is returned in the end with reduced implementation costs and shortened timelines to reach water quality goals. This presentation will provide an overview of the diagnostic monitoring process and offer low-cost monitoring alternatives to further stretch your diagnostic monitoring budget and achieve your water quality goals. Our goal is to empower all water resource professionals with inexpensive monitoring tools that allow the targeting of nutrient sources and best-use of limited restoration/implementation funds.