South Central/Southwest Wisconsin and North Central Illinois
Zone 3

Transmission system limitations in Zone 3

Zone 3 is undergoing significant new generation interconnection requests and different projects that will allow their energy deliverability across the region. In addition, there are multiple projects that will increase the reliability, condition, and performance of existing transmission assets. 

Electricity usage growing

Electric load is forecasted to grow approximately 0.16% annually through 2033 in Zone 3. 

Transmission projects in Zone 3

The most notable planned, proposed, and provisional network/asset renewal projects in Zone 3 are listed below along with their projected year of completion and the factors driving the need for the projects. 

Zone 3 includes the counties of:
  • Columbia , Wis.
  • Crawford (S) , Wis.
  • Dane , Wis.
  • Dodge , Wis.
  • Grant , Wis.
  • Green , Wis.
  • Iowa , Wis.
  • Jefferson , Wis.
  • Lafayette , Wis.
  • Richland , Wis.
  • Rock , Wis.
  • Sauk , Wis.
  • Walworth , Wis.
  • Winnebago (N) , Ill.

Zone 3 Planned Projects

Project DescriptionProject #In-service yearNeed driver
Rock County Reliability Project 12024Reliability
Gaston Road SS, DIC, Additional Transformer 22024T‑D interconnection
Duck Creek SS, DIC, New Substation 32024T-D Interconnection
Nelson Dewey – Bloomington 69-kV (Y-184), rebuild & OPGW 42025Reliability, Condition and Performance
Huiskamp – Ruskin (6937), Partial Rebuild 52025Condition and Performance
North Beaver Dam SS Asset Renewal & South Beaver Dam – North Beaver Dam, 69-kV (Y-59) Line Rebuild 62026Condition and Performance
Darlington – Rock Branch 69-kV (Y-109), Rebuild 72026Condition and Performance

Zone 3 Proposed Projects

Project DescriptionProject #In-service yearNeed driver
Wick Drive – Black Earth 69-kV, (Y-62), OPGW Addition & Partial Rebuild 82026Communication
Hillman – Darlington 138-kV (X-14/X-101), Rebuild 92028Condition and Performance

Zone 3 Provisional Projects

Project DescriptionProject #In-service yearNeed driver
Eden – Rock Branch 69-kV (Y-106) Uprate
South Beaver Dam – North Beaver Dam, 69-kV (Y-59) Line Rebuild
102027Economic, Condition and Performance
South Fond du Lac – Spring Brook 69-kV (Y-133), Rebuild 112032Condition and Performance