Minnesota lakes often fail to meet state water quality standards due to excessive levels of nutrients, such as phosphorus and nitrogen. In excess, nutrients can lead to uncontrolled algal growth that threatens aquatic life, limits recreation, and detracts from a lake’s public value. Lakes that fail to meet standards are placed on the Minnesota Pollution Control Agency’s impaired waters list, which is updated every two years.
Thanks to targeted water-quality improvement projects, more nutrient-impaired lakes were removed from the impaired waters list between 2020 and 2022 than in any two-year period in the previous 20 years. But since 2002, only 7% of nearly 700 nutrient-impaired lakes have been delisted. Senior Water Resources Engineer Greg Wilson has been helping Minnesota clients reduce nutrients in lakes for over 30 years. Here, Greg explains what lake managers should consider when embarking on a nutrient-reduction project.
Two factors often challenge nutrient-reduction efforts. The first is the need for a reliable set of water quality data and a water quality model. Modeling allows us to identify the sources of excess nutrients and develop reduction strategies, but it takes time to gather enough data to develop a trustworthy model. The second factor is funding and community buy-in. Nutrient reduction can take years of trial and error, so projects require a strong foundation of support. While these challenges are common, they can be overcome with persistence and resourcefulness. For example, engaging stakeholders—typically adjacent landowners—early and often can invite opportunities for volunteer support.
Lake managers should first consider whether their water-quality monitoring program will enable them to gauge progress. Without baseline water quality data and a plan for ongoing monitoring, it will be hard to know if our efforts are paying off. An adequate and consistent monitoring program from the start allows lake managers to adjust their strategies as results come in.
Alum treatment—injection of liquid aluminum sulfate—is a powerful nutrient reduction strategy for reducing phosphorus in lakes. Aluminum sulfate binds permanently to available phosphorus, preventing it from being consumed by algae in the summer months. This reduces phosphorus already in the lake, as opposed to phosphorus that enters a lake from external sources such as fertilizer, sediment erosion, and leaf litter. Alum is typically applied from a small barge, using GPS to navigate the lake while injecting prescribed dosages just below the surface. With proper dosing and ongoing control of external sources, nutrient-reduction benefits of alum treatment can last 10- to 20 years. Barr has used alum treatment in many successful nutrient-reduction projects, including one on Spring Lake for the Prior Lake–Spring Lake Watershed District—the largest alum treatment project in Minnesota.
Minnesota uses sales tax proceeds for Clean Water Fund grants that support nutrient-reduction projects. Many other states have established similar funding sources and/or leveraged Section 319 funding administered through the U.S. Environmental Protection Agency, as well as conservation programs administered through the U.S. Department of Agriculture. Barr has a long history of helping our clients secure funding for their nutrient reduction projects.
To learn more about addressing lake impairments, contact us.
Greg Wilson, senior water resources engineer, has more than 31 years of experience in the areas of hydrology and hydraulics, surface water quality, GIS, limnology, and watershed and lake management planning. He performs watershed and in-lake water quality modeling, recommends management actions, and facilitates technical-advisory meetings for development of lake management plans. Greg has conducted water-quality and water-quantity monitoring and modeling and/or Total Maximum Daily Load/Water Restoration and Protection Strategy studies for nearly 100 lakes.
Foundation assessment a critical first step for wind repowering
New heat-sensing drone sees the unseen
Natural resources plan addresses city’s changing ecosystem
To heal nutrient-impaired lakes, apply persistence and resourcefulness
EPA proposes maximum contaminant levels for six PFAS
Two projects honored for engineering excellence
Receive the latest editions right to your inbox and explore industry trends, projects, and company news.
New EPA standards for oil and natural gas storage tank venting systems
New wastewater discharge standards for coal-fired power plants
Hometown flooding experience inspires career aspirations
Choose your own adventure as an intern at Barr
Internship offers real-life experience in the Canadian oil sands
EPA finalizes GHG standards for electric power generation industry
Improving the ecological health of natural areas within your park system
From teenage errand boy to chief marketing officer
Ready or not, artificial intelligence is here to stay
Certain PFAS now designated as hazardous substances under CERCLA
EPA releases maximum contaminant levels for PFAS in drinking water
Envisioning reuse: The next chapter in the story of industrial water
Hear more about water reuse from Barr's experts
Project: Turning a facility’s wastewater into process water
Project: System evaluation to achieve zero liquid discharge
Navigating the storm: Effectively managing industrial stormwater
Seeing the picture below ground
New PFAS reporting requirements under TSCA
Engineer makes a career, and a hobby, out of modeling
Addressing water scarcity: A case study on aquifer storage and recovery projects
Stack test method OTM-50 announced to measure PFAS in air emissions
Q&A: From operations-based site experience to practical geotechnical mining solutions
Revolutionizing tomorrow through technology and innovation
Cost of removal and destruction of PFAS from wastewater effluent
4,000 wetlands and counting: Journeys of a wetland ecologist
Managing risks when decommissioning PFAS-impacted facilities
Developing a sustainable mine closure vision
Ecosphere Environmental Services, Inc. staff join Barr
A zoo with a view: Treetop Trail opens
Clean water for the Yanesha people of Peru
Adding RNG to your energy portfolio
Happy holidays from all of us at Barr!
Watershed-wide analysis improves strategies to manage climate change
An ecosystem approach to watershed planning and water resource protection
Stormwater O&M: When construction ends, the work begins
How will changes to the TRI/PFAS reporting rule affect your facility?
Barr brings a straightforward approach to Minnesota PFAS cost estimate study
Diving into the data as an air quality specialist
How safe is your tailings dam?
New technology expands access to solar energy
Slope repair puts solid ground under the skis
Creative solutions result in time and cost savings for clients
University flips the switch to “dark-sky-friendly" lighting plan
EPA program connects partners for sediment restoration
MSHA proposes new silica-exposure standards
The evolution of PFAS analytical methods over the last decade
Mining the Intermountain West: From operations to consulting
Six reasons to add RNG to your energy portfolio
Balancing power generation with air quality compliance
Wind turbine foundations now and in the future
Summarizing recent changes to NEPA
Making the most of every opportunity
Gaining real-world experience through Barr’s internship program
From a client’s perspective
Using waste heat recovery for carbon management
Minnesota's mine-reclamation legacy enters exciting new chapter
Building climate resilience through green infrastructure design
Navigating CCR compliance under recent EPA determinations
Municipal waste stream PFAS removal and destruction: Current alternatives and cost
EPA proposes rule to reduce ethylene oxide emissions from commercial sterilizers
Barr celebrates Founders Day: A CEO’s perspective
Five steps to develop a greenhouse gas inventory for agricultural manufacturing
How will the new PFAS MCLs affect NPDES permits?
Time to repower your wind energy site?
Adding lithium to mining operations: Environmental, permitting, and ESG factors
Adding lithium to mining operations: Engineering and design factors
Collecting data from the skies with reality capture technology
Green infrastructure and stacked-benefits projects
EPA proposes maximum contaminant levels for six PFAS in drinking water
Minnesota DNR releases new commercial solar siting guidance
Emerging PFAS destruction technologies
The Inflation Reduction Act: Manufacturing focus
Domestic uranium production on the rise
EPA's latest proposed rule eliminates PFAS reporting exemption
Introducing Barr’s ugly holiday sweater contest winner
Civil designs create homes for the holidays
Designing Africa's first potash processing facility
Q&A: Are mussels impeding your underwater project?
EPA begins enforcement of coal-ash disposal rule
Floodplain management expert joins Barr
From our CEO
Designing Africa’s first potash mine
The Inflation Reduction Act: Mining focus
The Inflation Reduction Act: Power focus
A deeper look into the promising new PFAS destruction approach
Tailings storage facilities: A unique challenge for a critical industry
The Inflation Reduction Act: Fuels focus
Making an impact in the Rocky Mountain Region
From Boy Scout to Senior NEPA Consultant
Stabilizing a community's backup water supply
Q&A: In your ESG journey, keep the destination in mind
Inflation Reduction Act opens door for energy investment
Reviving landings on Lake Michigan's Plum and Pilot Islands
PFAS: What’s all the hype?