Horizon West Transmission, LLC formerly (NextEra Energy Transmission West, LLC) and Pacific Gas & Electric Company

Estrella Substation and Paso Robles Area Reinforcement Project

(Application No. A.17-01-023)

Last Update: February 03, 2020

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Introduction and Background

Welcome to the California Public Utilities Commission (CPUC) web page for the environmental review of Horizon West Transmission, LLC (HWT) (formerly NextEra Energy Transmission West, LLC and Pacific Gas & Electric Company's (PG&E) (collectively referred to as "co-Applicants") proposed Estrella Substation and Paso Robles Area Reinforcement Project (the “Proposed Project”). The CPUC is the lead agency under the California Environmental Quality Act (CEQA) for the Proposed Project, and is therefore responsible for evaluating the Proposed Project’s potential environmental impacts.

The California Independent System Operator (CAISO) approved the development of the new 230/70 kilovolt (kV) Estrella substation and a new 70 kV power line to interconnect to the substation to improve reliability in San Luis Obispo County in its 2013-2014 Transmission Plan, Estrella Substation Project Description and Functional Specifications for Competitive Solicitation (CAISO 2014). Following its selection by CAISO in March 2015 as the approved project sponsors, the co-Applicants submitted to CPUC a Proponent's Environment Assessement (PEA) in January 2017, as part of its application (A.17-01-023) for Permits to Construct (PTCs), as specified in CPUC General Order (G.O.) 131-D. The PEA and related project documents are available under the "Project Links & Documents" heading below. Following five rounds of deficiency letters and responses between CPUC and the Applicant Team, CPUC deemed the application complete on July 24, 2018. CPUC is now conducting its independent environmental review of the Proposal Project. Additional information on the Proposed Project and the CPUC's environmental review process are also provided below.

Interactive Web Map

An interactive web map showing the Proposed Project and potential alternatives can be viewed here.

CPUC completed a Draft Alternatives Screening Report (ASR) in March 2019 (see below for further information). The alternatives shown on the web map reflect the screening results from the Draft ASR.

To view where project features are located in relation to your property, you can type in your address into the search bar at the top of the page or zoom in to your area of interest.

Project Links & Documents

PEA Deficiency Letters, CPUC Data Requests, and Applicant Responses

CPUC Request NEET West/PG&E Response Response Attachments
Deficiency Letter #1
(February 16, 2017 (36KB)
Response to Deficiency Letter #1 (May 18, 2017) (226 KB)
Deficiency Letter #2 (June 29, 2017) (171 KB)

Response to Deficiency Letter #2 (August 28, 2017)

Response Attachments
Deficiency Letter #3 (September 28, 2017) (125 KB) Response to Deficiency Letter #3 (January 22, 2018) (7.26 MB) Response Attachments
Deficiency Letter #4 (February 27, 2018) (152 KB)

Response to Deficiency Letter #4 (May 2, 2018)

Response Attachments

Deficiency Letter #5 (June 4, 2018) (399 KB)

Response to Deficiency Letter #5
(June 18, 2018)

Response Attachments

Data Request #1 (November 7, 2018) (174 KB)

Response to Data Request #1 (January 14, 2019) (927 KB) Response Attachments

Data Request #2 (April 15, 2019)

Response to Data Request #2 (June 25, 2019) (3.3 MB)

Updated Response to Data Request #2 (September 21, 2019) (3.4 MB)

Response Attachments

Data Request #3 (May 21, 2019) (2 MB)

CAISO Response to Data Request #3 (June 13, 2019) (180KB)

PG&E Response to Data Request #3 (August 14, 2019) (634 KB)

HWT Response to Data Request #3 (August 14, 2019)

Response Attachments

Data Request #4 (June 27, 2019) (8.4 MB)

Preliminary Response to Data Request #4 (September 21, 2019) (2.7 MB)

Confidential Response to Data Request #4 (October, 2019) (Redacted)


Data Request #5 (November 13, 2019) (216 KB)

Pending Spring 2020  


Project Objectives

Applicants' Stated Objectives

The objectives of the Proposed Project, as stated by the co-Applicants in their PEA, are as follows:

  • Increase reliability and mitigate thermal overloads and voltage concerns in the area by having an additional 230 kV source of power that will increase service reliability in northern San Luis Obispo County, and maintain compliance with North American Electric Reliability Corporation (NERC) reliability standards; and
  • Provide a location for future 21 kV distribution facilities with a 230/70 kV source near the anticipated growth areas in northern Paso Robles to efficiently add distribution capacity and improve service reliability when required in the Paso Robles Distribution Planning Area.
  • Balance Safety, Cost, and Environmental Impacts

CPUC's Project Objectives

As part of its authority as the lead agency under CEQA for preparation of the EIR for the Proposed Project, CPUC is responsible for identifiying appropriate project objectives to inform the CEQA process/evaluation, including the development and screening of project alternatives. These objectives may differ from the Applicants' stated objectives in their PEA. Based on its understanding of the fundamental underlying purpose of the Proposed Project, CPUC and its consultants have identified the following CEQA objectives for the Proposed Project:

  • Transmission Objective: Mitigate thermal overload and low voltage concerns in the Los Padres 70kV system during Category B contingency scenarios, as identified by the CAISO in its 2013-2014 Transmission Plan.
  • Distribution Objective: Accommodate expected future increased electric distribution demand in the Paso Robles DPA, particularly in the anticipated growth areas in northeast Paso Robles.

Proposed Project

Project Description

The Proposed Project is comprised of two components: Estrella Substation and the 70 kV Power Line. Each of these main components has several subcomponents, which are described below:

1. Estrella Substation Components

a. Constructing a new 230 kV substation to be operated by HWT

b. Constructing a new 70 kV substation to be operated by PG&E, with a location for future 70/21 kV distribution facilities

c. Constructing a 230 kV transmission line interconnection to be operated by PG&E

2. Power Line Components

a. Constructing a new approximately 7-mile-long 70 kV double-circuit power line between the new 70 kV substation and the existing San Miguel-Paso Robles 70 kV Power Line (new 70 kV power line segment), to be operated by PG&E.

b. Reconductoring (and pole replacement) of approximately 3 miles of the existing San Miguel-Paso Robles 70 kV Power Line from the interconnection with the new 70 kV double-circuite power line (described under "a" above) to the Paso Robles Substation.

A common neutral would be collocated along the entire length from Estrella Substation to Paso Robles Substation. A fiber optic line for communication services would be installed on the 70 kV power line to provide a fiber optic link between the Estrella Substation and Paso Robles Substation.

Project Location

As shown in the map below, the Proposed Project would be located within the northern portion of San Luis Obispo County, California, including portions of the City of Paso Robles. The nearest other communities are San Miguel, which is approximatelly 9 miles to the northwest, and Templeton, which is about 8.5 miles to the southwest.

Figure 1

Land uses in the Proposed Project area are a mixture of intensive agriculture and urban and rural residential development. North of State Route 46 and within the city limits, land uses consist of light industrial development, rural residential development, and wineries/vineyards. Topography in the vicinty of the project is generally rolling hills, with existing elevations ranging from approximately 920 feet to 960 feet above mean sea level.

The proposed Estrella Substation site is located on an approximately 15-acre portion of a 98.6-acre parcel of land and would be comprised of HWT's 230 kV substation and PG&E's 70 kV substation. The entire approximately 15-acre Estrella Substation site is currently planted with grape vines with 10-foot-wide span lengths.

The proposed power line would consist of a new, approximately 7-mile long 70 kV power line between Estrella Substation and the exisiting San Miguel-Paso Robles 70 kV Power Line and the replacement of approximately 3 miles of the existing line to where it connects to Paso Robles Substation.

Environmental Review


The CPUC deemed A.17-01-023 of HWT/PG&E complete on July 24, 2018, and is now conducting the CEQA review for the Proposed Project. As detailed further below, CPUC held a scoping meeting on August 7th in Paso Robles to solicit input regarding the scope and content of the EIR for the Proposed Project. A Scoping Summary Report is available under the "Project Links & Documents" section above. CPUC staff and consultants circulated a Draft ASR, and will be preparing a Final ASR to inform the alternatives analysis in the Draft EIR. The Draft EiR is currently in preparation. Once the Draft EIR is completed, it will be circulated for public review, and the CPUC will accept comments on it and hold a public meeting.

Scoping Period

The CPUC circulated a Notice of Preparation (NOP) of an EIR on July 31, 2018, and a revised NOP on August 1, 2018. The revised NOP corrected a figure that had inadvertently omitted several potential Project alternatives. The NOP included information on the Proposed Project and CEQA process, and described how to submit comments during the scoping period and attend the public scoping meeting. Circulation of the NOP initiated the scoping comment period, which lasted until August 31st.

The CPUC held a public scoping meeting on August 7th, 2018, from 6 p.m. to 8 p.m. at the Winifred Pifer Elementary School located at 1350 Creston Road in Paso Robles. The meeting was publicized in the local area newspaper and details of the meeting time and location were provided in the NOP, which was sent via direct mailings to numberous households, offices, and agencies.

The scoping meeting format consisted of a presentation by CPUC staff and consultants followed by opportunities for attendees to ask questions and submit comments. Written comment cards were provided to all meeting attendees, as well as information on how to access project documents and participate in the public review process going forward. A total of 50 individuals signed into the meeting in Paso Robles.

During the scoping period, CPUC received numerous comment letters from public agencies, the general public, and other entities. As described in detail in the Scoping Sumerary Report, scoping comments touched on a wide range of topics. The most common generalized comments are shown in the table below.

Table 2 from the Scoping Summary Report. Most Common Generalized Comments
by Number of Commenters

No. of Commenters

The proposed overhead power lines would have aesthetic impacts and be out of scale with the community.


Overhead power lines should be placed underground to reduce aesthetic impacts and/or minimize fire risk.


Overhead power lines could present hazards associated with EMFs.

The addition of overhead power lines could decrease property values for nearby properties.

The overhead power lines could present a fire hazard risk (e.g., if they were downed in an earthquake or in high winds).

General opposition to the Proposed Project power line route.

The overhead power lines would have noise impacts from the “buzzing” during operation.


Why is the project needed? The rationale for the Proposed Project is not well-founded.


The overhead power lines could adversely affect the flight path for CAL FIRE helicopters accessing the pond by the Circle B properties.

The Project 70-kV route alignments could necessitate removal of oak trees.

The Proposed Project and alternatives could impact bald and golden eagles in the area.


Project construction ground-disturbing activities could impact cultural resources.


Project construction activities could result in noise impacts.


There would be traffic impacts during Project construction.

Support for the Proposed Project power line route.

CPUC will consider the comments received during scoping period during preparation of the Draft EIR.

Draft Alternatives Screening Report

CPUC circulated a Draft ASR for public review and comment. The Draft ASR review period lasted from March 28th to May 10th, 2019. CPUC will consider the comments received on the Draft ASR in preparing the Final ASR, which will be included as an appendix to the Draft EIR. The Draft ASR and the comments received on the Draft ASR are available under the "Project Links & Documents" above.

The purpose of the ASR is to document the CPUC's efforts and process for developing a range of potentially feasible alternatives for the Proposed Project. The ASR will support and inform the analysis of project alternatives in the Draft EIR, and is intended to identify a reasonable range of potentially feasible alternatives that will be carried forward as part of the Draft EIR's detailed environmental analysis.

As described in detail in the Draft ASR, the following alternatives were identified for full analysis in the Draft EIR:

  • Alternative Substation Site (SS)-1: McDonald Ranch Substation Site
  • Alternative Power Line Route (PLR)-1: Estrella Route (Variations: PLR-1A, PLR-1C, and PLR-1D)
  • Alternative PLR-3: Strategic Undergrounding
  • Alternative Substation Expansion (SE)-1: Templeton Substation Expansion
  • Alternative SE-PLR-2: Templeton-Paso South River Road Route
  • Alternative Battery Storage (BS)-1: Battery Storage to Address Transmission Objective (in front of the meter) (Variations: BS-1A, BS-1B, BS-1C, BS-1D, and BS-1E)
  • Alternative BS-2: Battery Storage to Address Distribution Objective (in front of the meter)
  • Alternative BS-3: Behind the Meter Battery Storage (i.e., customer side of the meter)

Figure 3-1 from the Draft ASR identifies these alternatives and additional alternatives considered in the Draft ASR.

Behind-the-Meter Solar plus Storage Adoption Propensity Report

CPUC has completed its analysis of behind-the-meter (BTM) solar plus storage adoption propensity, which is being circulated as a supplement to the Draft ASR. The BTM Solar plus Storage Adoption Propensity Report (BTM Report) evaluates the potential for BTM solar and storage adoption by residential and commercial customers in the Paso Robles Distribution Planning Area, and whether such adoption could meet the objectives of the Proposed Project.

The BTM Report informs development of a BTM resources alternative (Alternative Battery Storage #3) for inclusion and analysis in the Draft EIR.

For Additional Information

The CPUC's Environmental Review Team is managing the environmental evaluation of the Proposed Project. To request additional information or to be added to the mailing list, please contact us by email, fax, or phone at:
Fax: (510) 350-3592
Toll-free voicemail: (844) 211-7510

Mail: Rob Peterson, CPUC
c/o Tom Engels
Horizon Water and Environment, LLC
266 Grand Avenue, Suite 210
Oakland, CA 94610

The CPUC's project manager for the Proposed Project is:

Rob Peterson
Energy Division
Infrastructure Permitting and CEQA
300 Capitol Mall, Suite 418
Sacramento, CA 95814



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