A River Connects Us
The Cannon River runs through Northfield, Minnesota and is the center of our community. The river has also been integral to the learning and applied opportunities of Carleton students. For example, many academic courses have included the Cannon River as a field or public engagement site, and more than 50 Integrated Comprehensive Exercises involving the river have been completed by students exploring its ecology, geology, history, and community development.
Why is Learning & Engaging the Cannon River Important?
We play an active role in the health, happiness, and future of our river and and our community. The river is home to fish, bald eagles, herons, turtles and more. It faces challenges from both climate change and agricultural land use. In Northfield, the Cannon River has exceeded the 100-year flood threshold three times in the last fifteen years. Likewise, nitrate and phosphorous are elevated, largely from upstream agricultural use. This, coupled with warmer surface waters associated with our changing climate, reduces oxygen, and impairs water quality harming ecosystems.
There are also human issues to weigh, such as cultural, fishing, and recreational uses of the river, that intersect with health and quality of life. Now, as our community actively plans and implements new riverfront infrastructure and landscapes, we hope to contribute to discussions underway that support flood protection, water quality, and environmental justice. The future is determined by what we do both upstream and on the riverfront.
Water: Engaging Climate Resilience & Environmental Justice

Goals
- Monitor Water Quality: Work together to measure water chemistry (like oxygen and nitrate levels) and clarity above and below the Ames Mill Dam. This information helps inform decisions about dam removal, climate-resilient riverfront development, and overall water quality improvement.
- Partner with Experts: Join forces with local organizations, the City of Northfield, and the MN Pollution Control Agency Volunteer Water Monitoring Program to regularly check water clarity, contributing valuable data to statewide efforts. Connect with watershed groups and community members. Support faculty, staff, students, and partners interested in developing connective projects.
- Promote Climate, Water, and Environmental Justice Awareness: Develop and support activities that boost understanding of climate, water, and environmental justice. This can involve hands-on water testing, reflecting on the river’s history or role in our lives, and activities that support choices people and organizations can make, such as what to plant to reduce flooding. It will also build literacy around upstream rural interests and local perspectives from underrepresented groups. We will share examples of activities and materials that support positive change.
- Engage Decision Makers: Make connections with individuals, organizations, city leadership, and state policymakers making decisions on water, bringing into the conversation data monitoring, perspectives learned through education, and more.
What Are We Testing For? How Are We Engaging? Why?
We are testing to understand water quality concerns related to water, climate, and land use decisions and plan to share and interpret our results. Engaging audiences directly in real time sampling using low cost, but reliable sampling tools supports broad engagement. We sample the below variables, some which are also part of statewide volunteer monitoring through the MN Pollution Control Agency. Others are included to deepen discussion related to climate change and dam removal.
Clean River Partners, the City of Northfield, and Carleton contributors (Sustainability, ENTS, Geology, Spanish) received a Local Climate Action Grant from the MN Pollution Control Agencey for Community Network Building and Cannon River Monitoring and Upstream Education to Support Northfield’s Climate Action Goals. This funding alllows us to install temperature and oxygen sensors above and below the Ames Mill Dam, develop interactive water education for all Northfield 5th graders to include climate change, and to host meetings that bring water quality and the perspectives of young people and other communities into discussions about riverfront development activities underway in the Northfield Riverfront Enhancement Action Plan. For example, we will engage to share and learn water interests with the Latine community through Palmar Álvarez-Blanco’s course this winter and students in the Sustainability Office will build a regular student-led engagement program.
See a map of our sampling locations.
Dissolved Oxygen
- Dissolved oxygen is important to aquatic life and the amount of oxygen in streams and lakes impacts what can live in the water.
- Nitrogen fertilizers can increase the amount of algae in the water. When the algae die and decompose, their decomposition process decreases the amount of oxygen in the water. Fish will die when oxygen levels get too low. In addition, different fish species survive at different oxygen level thresholds.
- We test for dissolved oxygen using CHEMets Dissolved Oxygen Kits. These are colorimetric and the reagents in the test vials react with the oxygen in the water to produce a color change proportional to the amount of oxygen in the water (see image below).
- Oxygen typically improves with restored water flow and reduced nutrients and overproduction of algae.
Nitrate
- Nitrogen fertilizer especially from agriculture easily solubilizes and enters both surface and groundwater as nitrate.
- Excess nitrate can cause algal blooms which die, decompose, and cause fish death.
- We test for nitrate using CHEMets Nitrate Kits. These are colorimetric and the reagents in the test vials react with the oxygen in the water to produce a color change proportional to the amount of nitrate in the water.
- Nitrate is a known major contaminant in the Cannon River and the state of Minnesota as well as other places where agriculture is the dominant land use. It can be reduced by practices including precision agriculture and strategies that reduce soil erosion, or support vegetation uptake (e.g. cover crops, buffers).
Water Clarity
- Water clarity affects the ability of sunlight to pass through the water. This can impact the ability of aquatic plant life to thrive.
- Water clarity is impacted by both the presence of suspended inorganic material (like soil) and organic material (like algae).
- Suspended particles can clog fish gills.
- Tillage increases turbidity and cloudiness, decreasing water clarity as sediments more easily enter the river in runoff.
- Lower clarity often decreases oxygen in the water, it is harder to photosynthesize in cloudy water.
- We test for water clarity using a secchi disk. As the disk gets lower into the water the lines on the disk are less visible. This is quantified and tells us about the water clarity.
Temperature
- Warmer water holds less oxygen.
- Dams slow the movement of water, allowing the sun to heat water upstream, therefore, decreasing the oxygen in the water.
- We measure temperature using a thermometer and their are temperature sensors at a nearby USGS stream guage.
- Surface water temperatures increase and ice cover has decreases through time in response to climate change. Damming can also increase water temperatures upstream.
Observational Measurements
We are also studying these parameters important to water conditions, ecosystems, and human use:
- Appearance
- Recreational Suitability
- Stream Stage

Project Background
This project is informed by Carleton’s institutional strategic plan and desire to deepen place-based student engagement and climate action where we live. It is also informed by Cannon River Working Group meetings that brought together Clean River Partners, City of Northfield, Carleton, and St. Olaf faculty and staff to identify on opportunities to collaborate in support of meeting Northfield Climate Action goals through riverfront and upstream projects. Finally, it draws from many curricular and research activities on the river, or in connection to choices and opportunities for clean water, sustainability, and environmental justice and we plan to summarize and share some of that work.
Cannon River Working Group Meetings
Between January and April 2024, Carleton hosted three meetings in partnership with Clean River Partners and the City of Northfield to explore ways that Carleton, St. Olaf, and other organizations might contribute to the Riverfront Development planning and implementation activities underway. Specifically connections were made to Northfield’s Climate Action Plan, and the planned reconstructure of Ames Mill Dam into a recreational rapids.
We explored shared interests in education, nature, and climate action projects happening at the colleges. We identified interests in helping people learn and process history and change, engaging with community science and public scholarship, and developing case studies that can inform ongoing decisions related to green and gray infrastructure. (Meeting 1 participants & synthesis, Meeting 2 participants & synthesis, Meeting 3).
Cannon River Comps Projects
Below are a few examples of water related student Comprehensive Exercise projects.
- Avital (Tali) Emlen, Geology (2022) – “Cannon River streamflow reconstruction using riparian silver maple growth: Analyzing the efficacy of silver maple in dendrohydrology”
- Charles C. Linneman, Geology (2017) – “Impact of Construction on River Morphology: River Engineering Survey, Cannon River, SE Minnesota (Faribault to Lake Byllesby)”
- Jesse Gourevitch, Madison Halloran, Henry Peyronnin, and Maggie Sullivan, ENTS (2014) – “Applying the Analytical Hierarchy Process to Small Dam Management: A Case Study of the Ames Mill Dam, Northfield, MN”
- Anthony Abercrombie, Cody Wang, and Liz Wilson, ENTS (2014) – “Languages Of Legitimacy: Understanding Nonpoint Source Pollution In the Cannon River Watershed Through Methodological Complementing”
- Evan Johnson, Geology (2012) – “Assessment of the Effects of Four Small Bridge Abutments on the Stability of the Banks of the Cannon River in the Cowling Arboretum, Carleton College, Northfield, Minnesota”
- Danny Smith, Studio Art (2012) – “Cannon River Project”
- Marisa Sowles, Geology (2005) – “Assessing Phosphorus Transportation and the High Risk Runoff Areas in The Cannon River Watershed, Southeastern Minnesota”
Programming on Campus & with Partner Organizations
Carleton Campus – We are now hosting regular sampling and conversation events with the Carleton community.
BeaverFest – We supported a water testing event at Lyman Lakes during Beaver Fest, April 2024.
River Bend Big Woods River Biomes Class, River Bend Nature Center – In June 2024 we shared the MN Climate Action Framework with informal educators and discussed how organizations can support climate resilience, especially related to water. Then we engaged in sampling the Straight River using our ongoing monitoring protocols.