Sewer Service Area Plan

What is Sewer Service Area Planning?

Sewer service area plans (SSA Plans) anticipate future wastewater needs, identify areas suitable for development, and help protect environmentally sensitive areas (ESAs) where development could have an adverse impact upon water quality. Under Federal and State rules, SSA Plans are required for larger urban areas and become part of areawide water quality management plans. SSA Plans are considered by Federal and/or State agencies when reviewing plans and grant applications for wastewater improvements, as well as during the State review of sanitary sewer extensions and certain private sewer laterals and interceptor mains.

The sewer service area (SSA) for the City of Superior delineates areas with a potential for sewered development by 2040, excluding ESAs. Inclusion of lands within the SSA boundary does NOT determine or guarantee that these lands will be developed or sewered by 2040.

City of Superior Sewer Service Area Plan

The current City of Superior SSA Plan was approved by the Wisconsin Department of Natural Resources (WDNR) on Monday, October 10, 2022. The next update to the SSA Plan will be completed in 2025.

The City of Superior is the local planning and administrative agency with the Superior Technical Advisory Committee serving as the local advisory and decision-making committee. WDNR has final decision-making authority over plan implementation, updates, or amendments.

The goals, policies, and procedures of the SSA Plan apply to the development and, especially, sewered development within the SSA boundary. Again, the inclusion of lands in the SSA does not suggest or guarantee that public sanitary sewer will be provided to all such areas.

Implications for Proposed Development and Sewer Extensions

Proposed development and sanitary sewer extensions within the SSA boundary shall be reviewed in accordance with the following process for consistency with the SSA Plan:

For Sewer Extensions – A Sewer Service Area Plan Conformance Review is required by State rules to install or expand a public sewage system. Under the SSA Plan, a sewer extension excludes plumbing in connection with buildings served (except PIMS as noted below), service laterals from buildings to a street main, and the maintenance or replacement of inadequate systems in areas previously served. A request for a Water Quality Management Sewer Extension Review Letter for a sewer extension must be submitted to the City of Superior by the developer. See Section 7.2 of the SSA Plan.

For Private Connections/PIMS – As specified by State rules (SPS 382.20(4)), certain private sewer connections and private interceptor main sewers also require a Water Quality Management Review Letter. A request for a Water Quality Management letter for private sewer connections and private interceptor main sewers must be submitted to the City of Superior by the developer. See Section 7.3 of the SSA Plan.

Requests for a Water Quality Management Review Letter listed above or questions regarding the requirements shall be sent via email to

When is a SSA Plan Amendment Required?

SSA Plan Amendments should be rare and avoided if possible. Four types of amendments may be made to the Sewer Service Area Boundary:

  1. Requests for boundary changes without the total acreage of the service area changing. (Land Swap Amendments)
  2. Requests to alter the boundary and the acreage of the service area. (Land Addition/Subtraction Amendments)
  3. Requests to add holding tank service areas to the plan. (Holding Tank Amendments)
  4. Requests for development of an environmentally sensitive area (ESA Amendments). An ESA shall not be encroached upon by an intensive land disturbance and shall be considered unbuildable until an amendment is granted or otherwise properly approved under the SSA Plan.

Amendments are submitted to the Superior Technical Advisory Committee following the process and application requirements in Section 7.5 of the SSA Plan.

Questions regarding SSA Plan amendments shall be sent via email to

What are Environmentally Sensitive Areas (ESAs) and how are they treated under the SSA Plan?

Section 3.5.1 of the SSA Plan defines the environmentally sensitive areas (ESAs) identified within the City of Superior. These include, but are not limited to:

  • Surface Waters
  • Floodplains
  • Wetlands
  • Steep Slopes, including banks and bluffs
  • Publicly-owned scientific and natural areas

Encroachment by an intensive land disturbance upon any of the above within the SSA shall not be allowed without a plan amendment, except certain exceptions identified in Section 5.3 of the SSA plan