Wastewater: Dredged materials management

If your project involves dredging a stormwater pond, please see the section at the bottom of this page titled, Stormwater sediment removal projects.

To help you determine what type(s) of regulatory oversight and/or permit is required at projects and sites involving the on-land management (storage, treatment, disposal and/or reuse) of dredged materials, this page addresses requirements for discharges from the project site and/or management control site(s). Issues related to the dredging activity itself are addressed by other regulatory entities (see Other Environmental Issues section on this page).

The MPCA is limiting its dredged material permitting activities: Stormwater pond dredging projects should follow the guidance for urban stormwater ponds in the section below. Only certain projects involving navigational dredging and similar activities that store, treat, dispose and/or reuse dredged materials on-land in Minnesota may require a permit. See “Do I need a Permit for my Site or Project” below.

All other projects are recommended to follow the guidance, requirements and best management practices described below including submission of the “Notification to Manage Dredged Materials Without a Permit” form. The MPCA is unable to provide additional technical assistance for projects not requiring a permit.

General information

What is dredged material?

Dredged material includes material that is excavated at or below the Ordinary High Water Level (OHWL) of waterbasins, watercourses, public waters, or public waters wetlands, as defined by Minn. Stat. 103G.005. Examples of dredged material include sediment from the navigational dredging for shipping cargo and freight in Minnesota's commercial ports, including material from the dredging in the main navigational channel as well as from the main navigational channel to a particular commercial shipping dock within the commercial port; and, dredge projects that require the removal of sediment from Minnesota waters at marinas and recreational boating areas.

Environmental considerations

Dredged material has the potential to impact the environment. Carriage water and hydrostatic water from hydraulic or mechanical dredging processes, as well as stormwater runoff from dredged material management, transfer and off-loading sites, has the potential to pollute surface water when discharged to waters of the state. The management of dredged material also has the potential to affect groundwater through on-land management methods, if not managed in consideration of environmental risk factors.

Depending on the specifics at the project site, including the type of dredging operation, where the project is located, and the pollutant level present in the dredged material will determine how the project is regulated by the MPCA.

Note: The MPCA does not currently authorize or otherwise regulate the actual dredging activity. However, dredging activity is subject to the water quality standards specified in Minnesota Rules chs. 7050, 7060 and 7090. The MPCA also reserves the right to require a Permittee to apply for and obtain an individual NPDES/SDS permit for dredging activity.

Guidance and best management practices

The management guide details the requirements for managing dredged materials in the State of Minnesota, and contains all the specific information you will need to determine what sampling and analysis is required, whether a permit is required, and how dredged material must be managed (treatment, storage, disposal and use/reuse requirements).

A brief regulatory guide and Best Management Practices (BMPs) for the management of dredged material has also been prepared.

Do I need a permit for my site or project?

A State Disposal System (SDS) permit may be required to store, treat, dispose and/or reuse dredged materials on-land in Minnesota if the dredged material originates from navigational channels and associated bays, harbors, docks and marinas, and  similar projects, from the following areas:

  • Mississippi River downstream of River Mile 857.6 (which is approximately at the Soo Line Rail crossing near St. Anthony Parkway in Minneapolis);
  • Minnesota River downstream of River Mile 27 (which is approximately 2 miles upstream of the CSAH 101 crossing at Shakopee);
  • St. Croix River downstream of River Mile 26 (which is approximately 3 miles upstream of the East Chestnut Street crossing at Stillwater);
  • St. Louis River downstream of the State Hwy 23 crossing;
  • St. Louis Bay or Duluth/Superior Harbor; and
  • Out-of-state projects.

Proposers of these projects should proceed to the flow diagram in Figure 1. If a permit is required, the type of permit required will vary depending on the level of pollutant contamination in the dredged material, whether effluent is being discharged, and how the dredged material and/or effluent is being managed.

Note: If the project is not located in the areas above, an NPDES/SDS permit for the management is not required.

Projects not requiring a permit are recommended to follow the guidance and best management practices, including submission of the Microsoft Office document icon Notification to Manage Dredged Materials without a Permit form. The MPCA is unable to provide additional technical assistance for these projects. The MPCA reserves the right to require a permit for any dredge material disposal or reuse if deemed necessary to achieve appropriate environmental protections.

A National Pollutant Discharge Elimination System / State Disposal System (NPDES/SDS) permit is required for any surface water discharge not authorized by Section 404 of the Clean Water Act, including stormwater. For non-stormwater discharges see the MPCA Wastewater webpage. Refer to the modified approach for dredging urban stormwater facilities in Chapter 4 and the MPCA Stormwater for more information about other types of stormwater permits. All stormwater sediment removal projects that disturb one or more acres of soil as a result of sediment stockpiling, use or reuse must obtain a NPDES/SDS construction stormwater permit unless otherwise exempted.

Figure 1 is intended to guide users through the process of determining appropriate management options for dredged material, and the associated permitting requirements for various management methods. Answering “yes” or “no” to a question will lead to the respective answer, in terms of how to proceed through the flow diagram, and the regulatory controls of a particular management route.

Figure 1. Permit Decision Flow Diagram for dredge projects located in the areas listed above.

Figure 1. Permit Decision Flow Diagram for Dredge Projects

Some types of projects do not require a permit from the MPCA. For example, the following types of projects do not require a permit from the MPCA for the management of dredged material:

  • Projects involving the removal of less than or equal to 3000 cubic yards of material with no surface water discharge, and is either:
    • more than 93% sand, as determined by the grain size analysis; and,
    • characterized as having contaminant values less than the relevant soil reference values for the proposed disposal option; or,
    • disposed at a site or landfill that already has an MPCA permit that is approved to manage dredged material (industrial waste management plan).
  • Projects involving the removal of more than 3000 cubic yards with no surface water discharge that is disposed at a site or landfill that already has an MPCA permit that is approved to manage dredged material (industrial waste management plan).

General permit number MNG990000 was previously in place to authorize the management of dredged material for sites or projects meeting the criteria outlined in the permit. This permit is currently expired and is in the process of being reissued. Until the MNG990000 is reissued, all projects required to obtain a permit are being issued individual permit coverage.

Management of dredged material

In general

In general, dredged material may be disposed at a permitted solid waste facility, through permitted on-site disposal, or through use or reuse for a beneficial purpose, including fill. Interim management methods, such as the short-term placement of dredged material during off-loading or rehandling activities, the temporary storage of dredged material for dewatering prior to reuse of the material, or the long-term storage of dredged material awaiting final disposal are often used for the management of dredged materials. These management methods can be used either at the dredge project site, at an off-site location, or a combination of the two.

Whether managed on-site or an another off-site location, there are a number of considerations for the proper management, mainly relating to mitigating the impact that the project and/or dredged material management area(s) have on storm water entering, passing through or leaving the site(s). These considerations are addressed either through the requirements of a permit, if required, or through the implementation of Best Management Practices (BMPs), if a permit is not required. Chapter 5 of the management guidance details management requirements for dredged materials.

Management levels for use/reuse

Based on the results of completed sediment characterization, that is, the type and level of pollutants in the material, dredged material is categorized into one or more Management Levels. The Management Level of a dredged material dictates the appropriate disposition of the material.

Dredged material is categorized into three management levels:

  • Level 1: suitable for use or reuse on properties with a residential or recreational use category;
  • Level 2: suitable for use or reuse on properties with an industrial use category; and,
  • Level 3: Contact MPCA staff for additional information on regulatory requirements for disposal.

Larger projects may produce dredge materials that can be segmented into areas with dredged materials that are distinctly different from each other. Subsets of dredged material may be able to be managed differently from each other, depending on the Management Level applicable to each discrete subset.

If subsets of Management Levels exist within the project, dredged material may be managed separately by subsets, i.e., each subset of dredged material is managed at the relevant Management Level; managed at the most restrictive Management Level, if separation and management by subset is not feasible or desired; or, managed at the most restrictive Management Level if subsets from a given project or multiple project, such as at a use/reuse staging area, are co-mingled prior to disposal.

Table 5 in Chapter 5 of the management guidance specifies the Soil Reference Values (SRVs) that are acceptable within each Management Level.

For projects requiring a permit

For projects requiring either an individual permit for management of dredged material, the appropriate management requirements will be placed into the permit, and depends on the specifics of the project. An individual permit is developed for a specific project or site activity, with specific process waste water, discharge location(s) and situation in mind.

In the application process, the following type of information would be submitted for the respective management area(s) and/or project(s) to be covered by the permit:

  • Description of the dredge project and any management area(s);
  • Description and status of receiving water; and,
  • The nature of the wastewater (what pollutant may be present).

These factors, as well as additional factors about the receiving water, (such as its water use class and level of attainment or impairment, and whether there are any endangered species), are reviewed to determine the appropriate pollutant limits and monitoring.

If permit coverage is required for your project, complete and submit the following permit application forms for non-stormwater projects.

If a permit is issued for the specific project or site activity, the permit will be unique to the project and provide specific terms and conditions that must be met. The permit application forms should be submitted at least 180 days prior to the anticipated initiation of excavation.

For projects NOT requiring a permit

A Notification to Manage Dredged Materials should be completed and submitted for all projects not requiring an MPCA permit. The notification form should be submitted at least 30 days prior to the initiation of dredge activities. This does not include projects for stormwater sediment removal from constructed stormwater collection and conveyance systems. Permits are not required when performing routine maintenance on stormwater conveyance and collection systems and the MPCA does not need to be notified of those sediment removal activities, but the MPCA recommends that you keep records and documentation of sediment removal projects.

In addition to completing and submitting the notification form, dredged materials should be managed in accordance with specified Best Management Practices (BMPs) to protect ground and surface waters of the state.

Storage and/or disposal of de minimus volumes of dredged material is authorized if managed in accordance with the guidance in the BMP fact sheet.

Dredged material management forms

For projects requiring a permit

Apply for permit coverage using the following forms. 

For projects requiring a permit, an annual report describing the disposition of the dredged materials is required.

For projects NOT requiring a permit

For projects not requiring permit coverage, complete and submit the Notification form (recommended):

Other environmental issues

In addition to the water quality concerns at dredged material management facilities, other environmental considerations may require additional permitting or oversight by various governmental entities.

Projects that impact Minnesota's water resources are regulated by a variety of state, local, and federal agencies. Dredge activities must not be initiated until all applicable federal, state and/or local approvals that may be required for a particular project have been obtained. This includes, but is not limited to, state permits regulating activities in the bed of public waters as defined in Minn. Stat. 105 from the Minnesota Department of Natural Resources (MDNR), federal permits for dredged or fill material from the US Army Corps of Engineers (USACE), and local permits from the appropriate Soil and water Conservation District, county or local unit of government (LUG).

An overview of environmental regulations pertaining to dredged material is summarized on US Environmental Protection Agency (EPA) Contaminated Sediments Program.

US Army Corps of Engineers

The MPCA is not authorized to issue NPDES permits for discharges of dredged or fill material from dredge activities [40 CFR 122.3 (b)]. The US Army Corps of Engineers' (USCOE) Regulatory Programs include Section 10 of the Rivers and Harbors Act of 1899 and Section 404 of the Clean Water Act. The St. Paul District's regulatory jurisdiction covers the states of Minnesota and Wisconsin.

401 Certification

Under the federal Clean Water Act, any time a federal permit is needed for activities which may result in a discharge into waters of the United States, an applicant for the permit must obtain a Section 401 Water Quality Certification. In Minnesota, the MPCA administers the 401 Certification Program

Minnesota Department of Natural Resources

Projects affecting the course, current, or cross-section of some water bodies may require a Public Waters Work Permit from the Minnesota Department of Natural Resources.

Environmental assessments

Environmental review looks at how a proposed project could potentially affect the environment and ways to avoid or minimize impacts before the project is permitted and built. Environmental review can be a one or two-step process - the shorter, less detailed Environmental Assessment Worksheet (EAW) or the longer, more complex and detailed Environmental Impact Statement (EIS).

For information about the Environmental Assessment process visit the Environmental Quality Board or  MPCA's Environmental review program.

Stormwater sediment removal projects

In 2012, stormwater sediment best management practices (BMPs) were revised and guidance is provided for sediment removal projects from constructed collection and conveyance systems.

Sediment removal BMP guidance includes three primary changes:

  1. Permits are not required when performing routine maintenance on stormwater conveyance and collection systems;
  2. The MPCA does not need to be notified of sediment removal activities. We recommend that you keep records and documentation of sediment removal projects (who did the removal, how much was removed, test results to characterize the waste, disposal location, and the date the sediment was removed and disposed), and;
  3. BMPs have been revised to include guidance from cities that have experience doing sediment removal projects. The guidance includes topics beyond just regulatory concerns.

The guidance specific to stormwater sediment removal projects is : PDF icon Managing Stormwater Sediment Best Management Practice Guidance (wq-strm4-16).

A short companion video to compliment the guidance is available below:


Who to call

Non-stormwater projects

The MPCA is unable to provide additional technical assistance for projects not requiring a permit. If you have questions regarding a project that requires a permit, call Emily Schnick at 651-757-2699.

Stormwater sediment removal projects

Don Berger at 651-276-7235