2025

10-Year
Assessment

Northeast Wisconsin
Zone 4

Transmission system limitations in Zone 4

Ongoing analysis of Zone 4 has identified several overloads and voltage limitations. The most severe limitations are expected to occur during both peak and off-peak periods.  Several area projects are also related to the underlying condition and performance of assets in Zone 4. 

Electricity usage growing

Peak electric demand typically occurs during the summer months, although the northern portion of Zone 4 typically experiences nearly equal summer and winter peaks. Paper mills and foundries in and around the Green Bay and Appleton metropolitan areas are some of the largest electricity users in the zone. 

Electric load is forecasted to grow at approximately 0.11 percent annually through 2035. Several large load interconnection projects in Zone 5 increase power flow from North to South, thus impacting the 345kV and 138kV transmission facilities between Zone 4 and Zone 5.  

Transmission projects in Zone 4

The most notable planned, proposed, and provisional network/asset renewal projects in Zone 4 are listed below along with their projected year of completion and the factors driving the need for the projects. 

Zone 4 includes the counties of:
  • Brown , Wis.
  • Calumet , Wis.
  • Dodge (NE) , Wis.
  • Door , Wis.
  • Fond Du Lac (E) , Wis.
  • Kewaunee , Wis.
  • Manitowoc , Wis.
  • Marinette (S) , Wis.
  • Menominee (S) , Wis.
  • Menominee , Wis.
  • Oconto , Wis.
  • Outagamie , Wis.
  • Shawano (E) , Wis.
  • Sheboygan , Wis.
  • Winnebago (E) , Wis.

Zone 4 Planned Projects

Project DescriptionProject #In-service yearNeed driverRegulatory Update
Plymouth Reliability Project12026T-D InterconnectionCPCN Approved in 2025
Danz Ave SW STA – University (WPS) 69kV (O-15), underground rebuild & OPGW22026Condition and PerformanceN/A
Hwy V – Structure 123 69 kV (Z-26), Rebuild32026Condition and PerformanceN/A
Tower Dr – Pulliam (P-16/R-70), Partial Rebuild42028Condition and PerformanceCA Targeted filing 2025
High Falls – Mountain 69kV (Y-77), Partial rebuild52028Condition and PerformanceFiling Requirement TBD
Valders SS, New 138/69 kV Substation62028Economic, ReliabilityCA Targeted filing 2026
Mullet River Area Reliability Project72028Reliability, Condition and PerformanceCA Targeted filing 2026

Zone 4 Proposed Projects

Project DescriptionProject #In-service yearNeed driverRegulatory Update
Appleton Area Reliability Project92029ReliabilityFiling Requirement TBD
Proposed Projects

Zone 4 Provisional Projects

Project DescriptionProject #In-service yearNeed driverRegulatory Update
Erdman - Riverside (ALTE) 69 kV (Y-82 / X-64 / X-37), Rebuild82028Condition and PerformanceFiling Requirement TBD
Aviation - North Fond Du Lac 138 kV (G-111), Partial Rebuild102029Condition and PerformanceFiling Requirement TBD
Maplewood - Badger 138 kV (W-75), Rebuild112029Condition and PerformanceFiling Requirement TBD
Maplewood - Pulliam SW YD 138 kV (X-76), Rebuild122029Condition and PerformanceFiling Requirement TBD