Ash River Sanitary Sewer Collection and Treatment System Project

Project Overview

Voyageurs National Park, the nation’s only water-based national park, is experiencing water quality impacts from wastewater generated by surrounding development. To address this, the Voyageurs National Park Clean Water Joint Powers Board was established to improve wastewater treatment and protect the Park’s interconnected lake system.

A Comprehensive Wastewater Plan, developed in 2010 and updated in 2022, identifies priority project areas based on septic system conditions and water quality risk, including Rainy Lake (Island View), Lake Kabetogama, Ash River, and Crane Lake.

For more information on the overall Voyageurs National Park Clean Water Projects, visit the Voyageurs National Park Clean Water Projects page.

Following the completion of previous priority area projects, Ash River has been designated as the subsequent focus for implementation. The Ash River Sanitary Sewer Collection and Treatment System Project is being developed to provide a centralized wastewater collection and treatment system for properties in the Ash River area. The project will replace individual septic systems with a managed system designed to meet current regulatory standards and improve long-term wastewater management.

The service area includes a mix of seasonal and year-round residential properties, as well as resorts and commercial establishments. Site conditions in the area including shallow bedrock, variable soils, high groundwater, and small lot sizes limit the feasibility and effectiveness of compliant individual subsurface sewage treatment systems (SSTS).

Project Need

A significant number of existing septic systems in the Ash River area are aging, noncompliant, or failing, contributing nutrients and pathogens to nearby surface waters and groundwater. Due to the direct hydrologic connection to surrounding lakes, these impacts can extend beyond localized areas.

A 2011 U.S. Geological Survey (USGS) evaluation of regional water quality found that nutrient inputs continue to drive recurring algal growth, indicating ongoing impacts to water quality. Excess nutrients such as nitrogen and phosphorus often from sources like septic system leakage and runoff are known to promote algal blooms and degrade aquatic ecosystems. Elevated nutrient levels are linked to declining biological health and increased nuisance plant and algae growth in surface waters. Algal blooms can reduce water clarity, deplete dissolved oxygen, and harm fish and other aquatic life, while also limiting recreational use and overall aesthetic water quality. 

The project was identified as a priority improvement area through the Comprehensive Wastewater Plan based on system conditions, environmental sensitivity, and proximity to high-use recreational waters. By replacing failing septic systems with centralized treatment, this project directly reduces nutrient inputs that contribute to algal blooms and water quality degradation.

Proposed Improvements

The project includes:

• Installation of a low-pressure sanitary sewer collection system
• Connection of properties within the defined service area
• Construction of a centralized wastewater treatment system
• Treated effluent management through an approved subsurface discharge system

This approach will provide a long-term, compliant wastewater solution and reduce reliance on individual septic systems.

Project Status

The project has advanced through planning and preliminary engineering and is currently completing the final design phase, including final design refinements and coordination with the Minnesota Pollution Control Agency for review and approval. Efforts are ongoing to secure funding and advance the project toward construction.

Planning and Coordination

The project is guided by the Voyageurs National Park Area Comprehensive Wastewater Plan, which evaluated wastewater management alternatives and identified priority service areas.

Implementation is coordinated through the Voyageurs National Park Clean Water Joint Powers Board in partnership with local units of government, state agencies, and federal partners.

Anticipated Outcomes

• Replacement of noncompliant and failing septic systems
• Reduction in nutrient and pathogen loading to surface water and groundwater
• Improved wastewater system reliability and regulatory compliance
• Long-term protection of water resources in the project area