Data center siting snapshot: Cook County, Illinois

Line miles are measured from the archived HIFLD Transmission Lines layer inside the Census county boundary. Mapped lines are not available capacity.

What the public record shows

The archived HIFLD map indicates approximately 328.3 miles of 345 kV transmission line within Cook County, with no miles recorded at 500 kV or 230 kV levels ^[1]. An additional 495.7 miles of 115–161 kV line are mapped in the area ^[2]. Commonwealth Edison (ComEd) is the owner of record for the most mapped 115 kV+ line miles ^[3]. Thirteen named line endpoints, typically substations or switchyards, touch these 230 kV+ lines ^[4]. ComEd’s mapped service territory covers part of the county, though boundaries are approximate ^[5].

As of 2026-11-09, records show no county- or city-level data center moratorium or ordinance for Cook County ^[6]. At the state and utility level, ComEd’s large-load deposits and transmission security agreements are in force, dated 2026-09-16 ^[7]. A Governor directive pausing the Data Center Investment Program is also in force, dated 2026-06-05 ^[8]. Several bills are pending, including SB4004 regarding aquifer protection ^[9], SB4016 for hyperscale data center regulation ^[10], HB5513 as a companion bill ^[11], and SB2181 for data center reporting ^[12].

Drafted by our local model from the numbered facts below, then checked sentence by sentence by a second model and a rules-based check.

Data center rules on record

Rule records come from The MW Desk legislation tracker, which includes rows from the Moratorium Nation dataset by Michael J. Bommarito (CC BY 4.0). Statuses change; confirm with the jurisdiction's own record.

Utilities on record

Commonwealth Edison (Comed). (HIFLD/EIA-861 territory polygons; approximate and often overlapping.)

Market context on The MW Desk: Chicago.

Sources

1. [1] The archived HIFLD map shows about 328.3 miles of 230 kV-and-above transmission line inside Cook County, IL: 0.0 miles at 500 kV or more, 328.3 miles at 345 kV and 0.0 miles at 230 kV. Source: HIFLD Transmission Lines (archived by SeerAI, CC BY 4.0)
2. [2] The same map shows about 495.7 miles of 115–161 kV line in the county. Source: HIFLD Transmission Lines (archived by SeerAI, CC BY 4.0)
3. [3] Owners of record with the most mapped 115 kV+ line miles in the county: Commonwealth Edison (ComEd). Source: HIFLD Transmission Lines (archived by SeerAI, CC BY 4.0)
4. [4] 13 named line endpoints touching 230 kV+ lines (usually substations or switchyards) are mapped inside the county. Source: HIFLD Transmission Lines (archived by SeerAI, CC BY 4.0)
5. [5] Retail electric utilities whose mapped service territory covers part of the county include: Commonwealth Edison (ComEd). Territory boundaries are approximate. Source: HIFLD Electric Retail Service Territories (EIA-861 based; archived by SeerAI, CC BY 4.0)
6. [6] Our records hold no county- or city-level data center moratorium or ordinance for Cook County as of 2026-11-09. Source: The MW Desk legislation tracker
7. [7] Illinois state/utility level, ComEd: Large-load deposits and transmission security agreements. Status: in force, dated 2026-09-16. Source: ComEd: secures over $1 billion in financial commitments from large load projects
8. [8] Illinois state/utility level, Illinois: Governor directive: pause Data Center Investment Program. Status: in force, dated 2026-06-05. Source: Gov. Pritzker pauses new data center tax incentives
9. [9] Illinois state/utility level, Illinois: SB4004 (Aquifer Protection Act) (Creates Data Center Water Transparency and Aquifer Protection Act; bars data centers from using Mahomet Aquifer water beginning 2027; bars permits for Mahomet withdrawals; requires existing users to transition by 2028; bans local nondisclosure clauses restricting water-use disclosure). Status: pending, dated 2026-06-17. Source: SB4004 Bill Status - Illinois General Assembly
10. [10] Illinois state/utility level, Illinois: SB4016 (Hyperscale Data Centers / POWER Act) (Comprehensive hyperscale data center regulation: cumulative impact review, public notice, community benefit agreements, NDA restrictions, water-impact permits, quarterly water reporting, water scarcity plans, energy and water reporting to ICC, hyperscale self-direct program, funds supported by annual fees based on peak demand, labor and equity provisions). Status: pending, dated 2026-05-30. Source: SB4016 Bill Status - Illinois General Assembly
11. [11] Illinois state/utility level, Illinois: HB5513 (Hyperscale Data Centers / POWER Act companion). Status: pending, dated 2026-05-27. Source: HB5513 Bill Status - Illinois General Assembly
12. [12] Illinois state/utility level, Illinois: SB2181 (Data Center Reporting) (Creates Illinois Data Center Energy and Water Reporting Act; annual energy and water reporting to IPA; IPA ratepayer-impact study; confidentiality, public access, enforcement, and penalties). Status: pending, dated 2026-05-22. Source: SB2181 Bill Status - Illinois General Assembly