Riverside Public Utilities

Hunter Substation Replacement Project

About the Project

At Riverside Public Utilities (RPU), we are always working to serve you better. To address reliability and capacity issues at the existing aged and vulnerable Hunter Substation, RPU is proposing retiring the existing Hunter Substation and replacing it with a new upgraded substation facility. The new substation will be built on an adjacent property that was acquired by RPU in 2018.

Hunter Substation is located at 1731 Marlborough Avenue, Riverside, CA 92507 and was commissioned in the early 1960s. The substation serves approximately 4,700 customers comprised of residents and businesses within the Hunter Industrial Park, Northside communities and University neighborhoods by the 215/60/91 Freeway interchange.

The new Hunter Substation will improve system reliability while meeting the existing power demands, supporting future development in the area, and maintaining power reliability. The new substation will be 69,000 Volts to 12,000 Volts (69kV/12kV) and will expand the number of 12kV distribution circuits to serve the future projected loads, support the ongoing 4kV to 12kV conversion project, and alleviate overloading of neighboring Riverside and University substations.

Project Map

Project Construction

The construction of the project will be broken down into three phases.

Phase 1:

  • Construction of a new 69/12kV Hunter Substation built adjacent to the existing Hunter Substation that will remain in service while the new substation is constructed.
  • Connection to four existing 69kV sub-transmission lines and connection to existing 12 distribution circuits.
  • Construction of five new underground 12kV distribution getaways.

Phase 2:

  • Decommissioning and demolition of the existing substation.

Phase 3:

  • Construction and operation of a warehouse facility that will store substation equipment and materials used by RPU for operation and maintenance of the RPU’s electrical grid system (optional phase).

Existing Hunter Substation

Proposed New Hunter Substation

Anticipated Project Timeline


Anticipated Date

Approval of the California Environmental Quality Act (CEQA) Mitigated Negative Declaration (MND)

November 2020

Award of contract to design-built contractor


Completion of design


Phase 1 Construction


Phase 2 Construction


Phase 3 Construction


Project Benefits

  • Improve system reliability with the replacement of aged substation equipment that are well beyond their useful life and are at higher risk of failure in service.
  • Improve electrical capacity to serve the existing and new forecasted electrical load demand of the surrounding area.
  • Address existing seismic concerns and the unreliable configuration of the existing substation.
  • Improve operational efficiencies.
  • Support ongoing 4kV to 12kV conversion project
  • Alleviate overloading of neighboring substations and increase contingency capacity.

Contact Information

For questions or concerns regarding this project, please contact:

Fady Megala, P.E.
Principal Engineer
(951) 826-5873
[email protected]