Welcome to the California Public Utilities Commission (CPUC) website for the California Environmental Quality Act (CEQA) review of San Diego Gas and Electric's (SDG&E’s) San Marcos to Escondido Tie Line (TL 6975) 69kV Project (proposed Project). An application for this project was submitted to the CPUC on November 15, 2017 (Application A.17-11-010). This site provides access to public documents and information relevant to the CEQA environmental review process.
Background
SDG&E filed Application No. 17-11-010 (A.17-11-010) filed on November 15, 2017 requesting a Permit to Construct (PTC) the San Marcos-Escondido TL 6975 69kV Project. The application included the Proponent's Environmental Assessment (PEA) prepared pursuant to Rule 2.4 of the CPUC's Rules of Practice and Procedure. The Project was subject to CEQA review because the CPUC was presented with a discretionary decision to approve or deny SDG&E’s PTC application. Prior to approving SDG&E’s application, and as required by CEQA, the CPUC analyzed potential environmental impacts associated with the Project and presented the findings in an Initial Study/Mitigated Negative Declaration (IS/MND) for public review and comment. This website provides access to public documents and information relevant to the CEQA review and mitigation monitoring processes.
Current Project Status
The CPUC voted unanimously to approve the Project and close the formal proceeding for the PTC on September 24, 2020. The CPUC’s Decision 20-09-034 was issued on October 5, 2020. On March 3, 2021, SDG&E submitted Notice to Proceed Request No. 1 (NTPR1) for construction of the Project and was approved by CPUC on September 9, 2021 (see below). Approval of NTPR1 included all project components (with the exception of the alternating current [AC] interference mitigation system and construction work proximate to known tribal cultural resource sites), proof of compliance with mitigation measures , and development of mitigation plans required by the Mitigation Monitoring, Reporting, and Compliance Program provided below. SDG&E commenced construction the week of September 13, 2021, which included mobilization of equipment and materials along Rock Springs Staging Yard and preparation of work areas along Segment 3. The approval of NTP-2 authorized the installation of the alternating current (AC) interference mitigation system in Segment 1. Finally, NTP-3 authorized power line and AC mitigation system work that is subject to MM CUL-3 (Data Recovery).
As of April 17, 2024, SDG&E reported to CPUC that all construction activities related to the project have been completed. CPUC approved SDG&E’s final archaeological monitoring report, final paleontological mitigation report, and final archaeological data recovery report on April 22, 2024. CPUC approved SDG&E’s final compliance summary report on April 24, 2024.Project Construction and Mitigation Monitoring
A Mitigation Monitoring, Reporting, and Compliance Program (MMRCP) was approved by the CPUC to ensure compliance with applicant proposed measures and CPUC mitigation measures identified in the Final IS/MND and adopted in Decision 20-09-034.
Mitigation Plans
Mitigation Plans prepared for the Project and approved by CPUC are available below:
- Soil and Dewatering Management Plan
- Construction Fire Prevention Plan (Revised September 2021)
- Health and Safety Plan
- Cultural Resources Monitoring Plan
- Paleontological Resources Monitoring and Mitigation Plan
- Supplemental Geotechnical Engineering Plan/Report
Notices to Proceed
SDG&E must obtain a Notice to Proceed (NTP) from the CPUC prior to initiating construction activities in accordance with the procedures outlined in the MMRCP. The NTP Requests (NTPRs) submitted by SDG&E and subsequent CPUC NTP approvals are provided in the table below:
| NTPR # | Desciption | Date Submitted | Date Approval |
| NTPR 1 | Initial request of pole removal, replacement, and implementation of new poles and staging areas for Segment 1,2, and 3. Also included is documentation of pre-construction submittals and mitigations. | 3/3/2021 | Approved 9/9/2021 |
| NTPR 2 | Installation of AC (alternating current) Interference Mitigation System, including five deep wells, solid state decouplers, and three coupon test stations. | 8/4/2021 | Approved 11/29/2021 |
| NTPR 3 | Includes one deep well and one coupon test station in the vicinity of the intersection of West San Marcos Boulevard and Discovery Street. Also includes portions of Segment 1 guard structures and underground distribution lines. | 6/8/2022 | Approved 7/7/2022 |
Minor Project Refinements
Minor project refinements (MPRs) are strictly limited to changes that will not trigger an additional permit requirement (except local government ministerial permits and associated requirements), do not substantially increase the severity of a previously identified significant impact based on criteria used in the IS/MND, create a new significant impact, are located within the geographic boundary of the study area of the IS/MND, and that do not conflict with any mitigation measure or applicable law or policy. The MPRs submitted by SDG&E are subsequent to CPUC approval and are provided in the table below.
| NTPR # | Desciption | Date Submitted | Date Approval |
| MPR 1 | The request would authorize the use of an additional temporary work area located between the existing work areas for existing transmission tower (Location 85) and existing transmission tower (Location 86) to create adequate workspace for a snub loading site (snub site). | 10/22/2021 | 11/8/2021 |
| MPR 2 | The request would authorize the use of 3 additional temporary work areas located north of Kauana Loa Drive/Harmony Grove Road near existing transmission towers, Location 107 and 108. | 11/3/2021 | 11/4/2021 |
| MPR 3 | The request would authorize the use of 3 additional work areas located near existing transmission tower Location 102 to facilitate wire installation operations associated with Segment 3. | 11/5/2021 | 11/12/2021 |
| MPR 4 | The request would authorize the use of two additional temporary work areas located within the transmission right-of-way (ROW) at existing transmission towers, Location 81 and 89. | 11/12/2021 | 12/21/2021 |
| MPR 5 | The request would authorize the relocation of Location 77 and its associated work area as well as an additional temporary work are north of Location 74 to facilitate wire installation and reconductoring work associated with Segment 3. | 12/15/2021 | 1/18/2022 |
| MPR 6 | The request would authorize the relocation of Location 78 and its associated work area to facilitate wire installation operations associated with Segment 3. | 1/20/2022 | 2/7/2022 |
| MPR 7 | The request would authorize the use of five temporary work areas to facilitate pier foundation pole installation operations associated with Segment 2. | 2/16/2022 | 2/25/2022 |
| MPR 8 | The request would authorize the use of existing access roads, which provide access to Locations 65 through 68 in the City of San Marcos and Locations 110, 111 and 112 in the City of Escondido. | 3/16/2022 | 3/18/2022 |
| MPR 9 | The request would authorize the use of an additional temporary work area at Location 59 to facilitate grading, pier foundation and pole installation activities. | 3/17/2022 | 3/25/2022 |
| MPR 10 | The request would authorize the use of additional work areas at Locations 51-54 as well as the use of an existing access road to Location 54 to facilitate pole and overhead wire installation activities. | 4/13/2022 | 5/3/2022 |
| MPR 11 | The request would authorize the use of additional work areas at Locations 2.1, 3 and 7 to facilitate pole and overhead wire installation activities in Segment 1. | 5/11/2022 | 5/31/2022 |
| MPR 12 | The request would authorize a revised work area at Location 56 and an additional work area near Location 8. | 5/20/2022 | 5/26/2022 |
| MPR 13 | The request would authorize the use of a helicopter incidental landing area within the approved work area for Location 62. | 7/29/2022 | 8/1/2022 |
| MPR 14 | The request would authorize redesigned work areas at Location 4, 5, and 6 and the installation of a meandering sidewalk. | 9/1/2022 | 9/8/2022 |
| MPR 15 | The request would authorize the use of a new temporary construction access road to Location 36. | 9/8/2022 | 9/8/2022 |
| MPR 16 | The request would authorize the use of a new temporary work areas at Locations 20 or 21. | 9/16/2022 | 9/21/2022 |
| MPR 17 | The request would authorize the use of a new temporary work area for the reconstruction of the screen wall at Location 49. | 9/29/2022 | 10/10/2022 |
| MPR 18 | The request would authorize the relocation of a new pole at Location 4, installation of a meandering sidewalk around the new pole, and an additional work area to accommodate these modifications. | 1/6/2023 | 1/12/2023 |
Quarterly Reports
According to the MMRCP (provided above), SDG&E must provide the CPUC with written quarterly reports of the Project construction activities, which include progress of construction, resulting impacts, mitigation implemented, and all other noteworthy elements of the Project. Quarterly reports are required as long as mitigation measures are applicable.
In addition to SDG&E-prepared quarterly reports, the CPUC must compile its own separate quarterly report at the close of the calendar quarters (i.e. January, April, July, and October). The CPUC quarterly report provides an overview of the Project construction activities completed during the quarter, as well as consolidated reports of noncompliance and corrective actions, APM and mitigation implementation/completion, and minor Project refinements.
SDG&E Quarterly Reports
SDG&E Quarterly Report (January, 2022)
SDG&E Quarterly Report (April, 2022)
SDG&E Quarterly Report (July, 2022)
SDG&E Quarterly Report (October, 2022)
SDG&E Quarterly Report (January, 2023)
CPUC Quarterly Reports
CPUC Quarterly Report (January 2022)
CPUC Quarterly Report (April, 2022)
CPUC Quarterly Report (July, 2022)
CPUC Quarterly Report (November, 2022)
CPUC Quarterly Report (March, 2023)
CPUC 2023 Monitoring Report (December, 2023)
Final Compliance Report
SDG&E
SDG&E’s Final Compliance Summary Report includes an overview of compliance with the requirements in the Mitigation Monitoring, Reporting and Compliance Program for the Project. This includes the final status of compliance with Applicant Proposed Measures (APMs) and mitigation measures implemented by resource area. This report provides details regarding the compliance-related activities conducted by SDG&E during the Project.
SDG&E TL 6975 Final Compliance Summary Report - 2024
CPUC
As the CEQA lead agency for the Project, the California Public Utilities Commission (CPUC) provided regulatory oversight of construction throughout the entire construction period. In accordance with the Final Initial Study/Mitigated Negative Declaration (IS/MND) for the Project, CPUC’s environmental consultant provided third-party oversight of SDG&E’s compliance implementation and coordinated with SDG&E’s environmental consultants. The CPUC team’s primary responsibility was to ensure adherence to the Project’s environmental requirements and mitigation measures. This Final Compliance Monitoring Report, in combination with SDG&E’s Final Compliance Summary Report provides the CPUC with an administrative record of environmental compliance with applicable measures and conditions as identified in the IS/MND for all Project construction activities.
Final Compliance Monitoring Report, April 2024
Project Overview
The proposed Project (see Figure 1) would occur in the cities of Carlsbad, Escondido, Vista and San Marcos, and in unincorporated San Diego County, California. Two auxiliary staging yards located in the city of San Diego are proposed for Project use. The proposed Project components at each location are summarized (by segment) below:
- Segment 1 Rebuild (San Marcos Substation-Melrose Tap). Rebuild approximately 1.8 miles of an existing 69kV circuit (TL 680C) to create a double circuit from San Marcos Substation to Melrose Tap. Construction at San Marcos Substation including installation of a new circuit breaker par, seven piers, and an A-frame for the new line. Along Segment 1, all wood pole structures would be replaced with steel poles; porcelain insulators would be replaced with polymer insulators.
- Segment 2 New Build (Melrose Tap-Meadowlark Junction). Construct 2.8 miles of new single-circuit 69kV overhead power line on new steel poles in the existing SDG&E transmission corridor from Melrose Tap to Meadowlark Junction adjacent to existing TL 13811/13835 power line, approximately 50-feet east of the centerline of the existing structures.
- Segment 3 Reconductoring/Re-energizing (Meadowlark Junction-Harmony Grove Rd to Escondido Substation). Transition new line (described under Segment 2, above) and reconductor approximately 7.4 miles of power line; remove and replace existing copper conductors with new 636 ACSS/AW conductors and existing porcelain insulators with polymer insulators; construction at the existing Escondido Substation to accommodate new circuit.
The proposed Project would include a combination of new overhead single-circuit electric power line structures, rebuild of existing structures from single circuit to double circuit, and the reconductoring and re-energizing of existing conductors. The majority of the new build and reconductored portions of the power line would occur within existing rights-of-way (ROW)s. A portion of the Project (Segment 1 rebuild) would require the widening of existing ROW.
The purpose of this proposed Project is to ensure the reliability of the transmission system, meet the State of California’s policy goals, accommodate load growth, and improve system efficiency in SDG&E’s service territory. SDG&E has identified the following objectives:
- Eliminate North American Electric Reliability Corporation (NERC) Category P0 (Cat A) and Category P1 (Cat B) violations on existing TL 684 (Escondido to San Marcos) and TL 680C (San Marcos- Melrose Tap) and;
- Meet mandatory NERC reliability criteria in the Escondido Area Load Pocket and alleviate the existing 69 kV congestion at the Escondido/ San Marcos Substations.
Application and Proponent’s Environmental Assessment
On November 15, 2017, SDG&E filed an application (A.17-11-010) for a PTC which included a Proponent’s Environmental Assessment (PEA) for the proposed Project pursuant to Rule 2.4 of the CPUC's Rules of Practice and Procedure.Environmental Review
The CPUC has prepared a Draft Mitigated Negative Declaration (Draft MND) to evaluate the environmental effects of the SDG&E San Marcos to Escondido Tie Line (TL)6975 69kV Project. The table below shows milestones and anticipated dates associated with the environmental review process.
| Project Milestones as of April, 2024 | |
|---|---|
| Milestone | Date |
| Application and PEA submitted by SDG&E | November 15, 2017 |
| CPUC PEA Deficiency Letter 1 | December 15, 2017 |
| SDG&E Response | January 12, 2018 |
| CPUC PEA Deficiency Letter 2 | January 26, 2018 |
| SDG&E Response | February 28, 2018 |
| Application and PEA - deemed complete | March 16, 2018 |
| Draft Initial Study/Mitigated Negative Declaration (Published) | April 1, 2019 |
| Public Comment Period | April 1, 2019 – May 30, 2019 |
| Public Meetings (2) | April 30, 2019 |
| Final Initial Study/Mitigated Negative Declaration (Published) | January 10, 2020 |
| Administrative Law Judge (ALJ) Proposed Decision | August 5, 2020 |
| CPUC Approval of Proposed Project | September 24, 2020 |
| Notice of Determination (NOD) posted | September 25, 2020 |
| CPUC Decision Issued | October 5, 2020 |
| NTPR1 Approved | September 9, 2021 |
| Start of Construction | September 2021 |
| NTPR2 Approved | November 29, 2021 |
| NTPR3 Approved | July 7, 2022 |
| Energization of Project | February 28, 2023 |
| Conclusion of Construction | April 17, 2024 |
| CPUC Approval of SDG&E Final Project Documentation | April 24, 2024 |
| CPUC Deems Project Construction Complete, Closes the Environmental Review Process, & Compliance Oversight Process/Issues CPUC Final Compliance Monitoring Report | April 24, 2024 |
Public Comment Period and Meetings
The Draft IS/MND was made available for an extended 60-day public and agency comment period, commencing on April 1, 2019, and ending May 30, 2019. The public, agencies, and interested parties presented comments and concerns regarding the Project and the adequacy of the Draft IS/MND. Comments were received through mailed letters, e-mail, comment cards, an on-line comment submittal website, and petition, as well as through verbal comment recorded at the two public meetings (see below). These submitted comments are part of the Project’s administrative record, which is public information, subject to disclosure under the California Public Records Act.
The CPUC conducted two public meetings to receive oral and written comments from the public, agencies, and interested parties. The meetings were held as follows:
Tuesday, April 30, 2019 |
Tuesday, April 30, 2019 |
Copies of the public Draft IS/MND were made available for public review at these libraries during the comment period and remain available for informational purposes on this project website.
San Marcos Library |
Escondido Public Library |
Carlsbad City Library |
Documents Available for Review
Public documents related to the SDG&E Application for a Permit to Construct (PTC) and the PEA for the proposed San Marcos-Escondido Tie Line (TL6975) Project can be found here:
CPUC Final Decision
Attachment A
ALJ Proposed Decision
Notice of Determination (NOD)
Final IS/MND
Final IS/MND Appendices
Public Draft IS/MND
Public Draft IS/MND Appendices
Notice of Intent (NOI)
SDG&E PTC Application (A.17-11-010) (November 15, 2017)
Certificate of Service, Attachment 1 (November 15, 2017)
Proponent's Environmental Assessment PEA for TL6975 (November 15, 2017) (21.3 mb)
Letter of Completeness (March 16, 2018)
PEA Technical Appendices
PEA Appendix 3 Detailed Route Map, Structure Details, Agency Correspondence (November 15, 2017) (12.1 mb)
PEA Appendix 4.3 Air Quality (November 15, 2017) (986 kb)
PEA Appendix 4.4D Bio NCCP (November 15, 2017) (27.0 mb)
PEA Appendix 4.8-B Fire Plan (November 15, 2017) (2.56 mb)
PEA Appendix 4.12 Noise (November 15, 2017) (5.56 mb)
Data Requests, Responses and Attachments
CPUC PEA TL6975 Deficiency Letter 1 (December 15, 2017)
SDG&E Response TL6975 Deficiency Letter (January 12, 2018)
Attachment 1 GIS shapefiles (no link)
Attachment 2A SM Sub Plan Profile
Attachment 2B ES Sub Plan Profile
Attachment 3A Photo Points Map book
Attachment 3B Existing Facilities
Attachment 3C Visual Sims
Attachment 4 NA Contact Program
Attachment 5 Geotechnical Investigation
CPUC PEA TL6975 Deficiency Letter 2 (January 26, 2018)
SDG&E Response TL6975 Deficiency Letter 2 (February 28, 2018)
Attachment 1 Load Forecast
Attachment 2 Powerline Route Map
Attachment 3A SM Sub Plan Profile
Attachment 3B ES Sub Plan Profile
Attachment 4 Power Flow Plots (confidential)
Attachment 5 2017 Revised HCP
Attachment 6 Herbicide Blend Recommendations
Attachment 7A Cultural Resources Report Non-confidential
Attachment 7B CR Report Supplemental Figures
Attachment 8 Table of Databases
Attachment 9 SDG&E Construction Water Sourcing Investigation Plan
Attachment 10 SDG&E BMP Implementation Plan
Attachment 11 VWD Will-Serve Letter
CPUC TL 6975 Data Request 1 (April 23, 2018)
SDG&E TL6975 Data Request 1 Responses - Cover Letter (May 15, 2018)
SDG&E TL6975 Data Request 1 Responses (May 15, 2018)
Attachment 1 Record of GIS Data Received
Attachment 2 Pole Inventory
Attachment 3 SM Sub Plan Profile
Attachment 4 Project Viewpoint Photos
Attachment 5 TL 6975 Project CalEEMod
Attachment 6 TL 6975 PEA Corrected Tables 3-10 and 3-13
Attachment 7 Equipment and Haul Truck Trips per Phase
CPUC TL 6975 Data Request 2 and SDG&E Response (May 22, 2018)
CPUC TL 6975 Data Request 3 (June 28, 2018)
SDG&E TL6975 Data Request 3 Responses - Cover Letter (July 16, 2018)
SDG&E TL6975 Data Request 3 Responses (July 16, 2018)
Attachment 1 AC Interference Analysis & Mitigation System Design
Attachment 2 Traffic Control Mapbook
Historic Resource Inventory and Evaluation Report
CPUC TL6975 Data Request 4 (July 24, 2018)
SDG&E TL 6975 Data Request 4 Responses (August 7, 2018)
Attachment 1 TL6975 SDG&E Helicopter Aviation Operations Manual
Attachment 2 TL6975 SDG&E PEA Project Description Revisions
CPUC TL6975 Data Request 5 (October 30, 2018)
SDG&E TL 6975 Data Request 5 Responses (November 6, 2018)
CPUC TL6975 Data Request 6 (November 9, 2018)
SDG&E TL 6975 Data Request 6 Responses (November 21, 2018)
Attachment 1 AC Mitigation Design GIS shapefiles (no link)
Attachment 2 AC Mitigation Design GIS KMZ files (for Google Earth)
CPUC TL6975 Data Request 7 (January 4, 2019)
SDG&E TL 6975 Data Request 7 Responses (January 18, 2019)
CPUC TL6975 Data Request 8 (May 30, 2019)
SDG&E TL 6975 Data Request 8 Responses (June 9, 2019)
TL6975 Escondido - Project Route Overview
TL6975 San Diego County - Project Route Overview
TL6975 San Marcos - Project Route Overview
TL6975 San Marcos - Escondido Project - City of Escondido (April 15, 2019)
TL6975 San Marcos - Escondido Project - County of San Diego (April 26, 2019)
TL6975 San Marcos - Escondido Project - City of San Marcos (April 23, 2019)
CPUC TL6975 Data Request 9 (July 8, 2019)
SDG&E TL 6975 Data Request 9 Responses (July 9, 2019)
CPUC TL6975 Data Request 10 (July 29, 2019)
SDG&E TL 6975 Data Request 10 Responses (August 27, 2019)
CPUC TL6975 Data Request 11 (September 6, 2019)
Item 1 - Photosimulation (September 18, 2019)
Item 2a - Response Summary
Item 2b - SDG & ELEHCP Summary Report (Amended August 8, 2019)
Item 2c - SDG & ELEHCP Project Pending Post Construction Reports (Amended August 8, 2019)
Item 3 - Appendix 3-A Mapbook
CPUC TL6975 Data Request 12 (October 17, 2019)
SDG&E TL6975 Data Request 12 Response (October 24, 2019)
CPUC TL6975 Data Request 13 (October 23, 2019)
SDG&E TL6975 Data Request 13 Response (October 30, 2019)
For Additional Information
The CPUC, through its Environmental Review Team, is managing the mitigation monitoring effort for the Project. To request additional information, or to be added to the mailing list please contact us by email or phone, as follows:
Email:TL6975SanMarcos@esassoc.com
Voicemail: 619.719.4207
Trevor Pratt
California Public Utilities Commission
Energy Division - Infrastructure Permitting & CEQA
505 Van Ness Avenue, 4th Floor
San Francisco, CA 94102
Email:Trevor.Pratt@cpuc.ca.gov