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Reference

Glossary

A plain-language guide to the players, places, species, and terms that recur across the effort to stop SDG&E's IV-NoS / "Golden Pacific" 500 kV transmission line through Temecula.

Grouped into Players & Organizations, Places & Geography, Species, and Acronyms & Terms, alphabetized within each. Bracketed numbers like [1] point to the authoritative source in the Sources list at the end; entries without a number are common-usage definitions.

Players & Organizations

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Army Corps
U.S. Army Corps of Engineers; issues Clean Water Act §404 dredge/fill permits for work in waters of the U.S. — a creek-crossing permit gatekeeper. [10]
Blackstone
global private-equity firm; financial backer of the California Grid Holdings (CalGrid) bid for the project.
BLM
Bureau of Land Management; federal land manager. Three of the four competing (non-winning) routes crossed BLM land.
CAISO
California Independent System Operator; the nonprofit operator of California's bulk electric grid. It identifies transmission "need," ran the competitive solicitation, and classified IV-NoS as "policy-driven."
CalGrid
California Grid Holdings (Blackstone-backed); one of the four qualified bidders for the project; did not win.
CalTrout
California Trout; conservation nonprofit leading Southern California steelhead recovery on the Santa Margarita.
CDFW
California Department of Fish & Wildlife; issues the §1602 Lake/Streambed Alteration Agreement and administers the state Endangered Species Act. [12]
CEC
California Energy Commission; the state's energy-planning agency; sets the load forecast and houses the SB 100 program behind the "policy-driven" need.
City of Temecula
the municipality in the line's path; its City Council voted unanimously to oppose the project.
CPUC
California Public Utilities Commission; the state regulator that decides whether and where the line is built (issues the CPCN) and is the lead agency for environmental review. The central venue for stopping it.
EMWD
Eastern Municipal Water District; one of the public water agencies overlying the Temecula Valley groundwater basin (with RCWD and Elsinore Valley MWD). [18]
FERC
Federal Energy Regulatory Commission; the federal regulator that sets the utility's transmission return (ROE) under the "just and reasonable" standard and the long-term regional planning rules (Order 1920). It sets the money, not the siting. [7]
Horizon West Transmission (HWT)
a NextEra affiliate that won CAISO's 2024 solicitation; it retained the North-of-SONGS substation and assigned the 500 kV line to SDG&E in August 2025.
Lotus Infrastructure
infrastructure investor; bid the project jointly with Southern California Edison and did not win.
MWD
Metropolitan Water District of Southern California; the regional wholesaler from which RCWD imports the majority of its supply (State Water Project + Colorado River) — context for how much the local Temecula aquifer matters.
NextEra
NextEra Energy / NextEra Energy Transmission (NEET); parent of Horizon West Transmission, the competition winner.
NOAA Fisheries
National Oceanic & Atmospheric Administration (Fisheries); lists and recovers the Southern California steelhead and designates its critical habitat on the Santa Margarita. [28]
Pechanga
Pechanga Band of Luiseño Indians; federally recognized tribe whose ancestral territory spans the corridor; steward of the ~2,000-year-old sacred oak Wi'áaşal.
Public Advocates Office
the CPUC's independent ratepayer-advocate office (formerly ORA, the Office of Ratepayer Advocates); a potential ally on cost.
RCA
Western Riverside County Regional Conservation Authority; administers the MSHCP (implemented by the Riverside County Transportation Commission since January 2021). [14]
RCTC
Riverside County Transportation Commission; the managing agency of the RCA/MSHCP.
RCWD
Rancho California Water District; the retail water district for the Temecula area. It draws on the Temecula Valley basin and banks recharge in the Pauba Valley, so it is a directly affected, standing party on construction dewatering. [29]
Riverside County
the county the contested segment runs through; there is precedent for a county resolution opposing a transmission line through conservation lands.
RWQCB
Regional Water Quality Control Board; issues CWA §401 water-quality certifications and Waste Discharge Requirements (including construction dewatering). Riverside straddles the San Diego (R9) and Santa Ana (R8) regions. [11]
Santa Margarita River Watershed Watermaster
the court-appointed administrator of the adjudicated Santa Margarita watershed (including the Temecula Valley basin) under the US v. Fallbrook decree; the body to notify about construction dewatering. [17]
SCE
Southern California Edison; investor-owned utility; bid the project with Lotus Infrastructure and did not win (and built the cost-overrun "sister" line cited as precedent).
SDG&E
San Diego Gas & Electric; the regulated investor-owned utility (serving San Diego and Orange counties, not Riverside) that now owns and would build the 500 kV line.
SDSU
San Diego State University; manages the Santa Margarita Ecological Reserve.
Sempra
Sempra Energy; SDG&E's parent holding company.
The Nature Conservancy
conservation nonprofit; a Santa Margarita Ecological Reserve management partner.
USFS
U.S. Forest Service; manages Cleveland National Forest, crossed by non-winning routes.
USFWS
U.S. Fish & Wildlife Service; the federal agency for Endangered Species Act listing and §7 consultation on listed species (arroyo toad, least Bell's vireo). [8]
Wildlands Conservancy
conservation nonprofit active in Santa Margarita watershed protection.

Places & Geography

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Agua Tibia Mountains
the Agua Tibia Mountains / Agua Tibia Wilderness (northwest Palomar Range, Cleveland National Forest), between Pala and Temecula; an ecological wilderness the route approaches.
Anza-Borrego
Anza-Borrego Desert (State Park); the desert the Sunrise Powerlink was rerouted to avoid — a key precedent.
Camp Pendleton
Marine Corps base at the Santa Margarita River's mouth; the United States is the senior water-rights holder in the US v. Fallbrook decree, and the estuary is steelhead critical habitat. [17]
Cleveland National Forest
the national forest (Palomar Ranger District) crossed by non-winning routes; home to the Agua Tibia Wilderness.
De Luz
rural area west of Temecula referenced in alternative-route and corridor discussion.
Great Oak Ranch
Pechanga land holding Wi'áaşal, a ~2,000-year-old sacred coast live oak; near the historic Valley-Rainbow route.
I-15
the interstate freeway that severed the Santa Ana–Palomar wildlife linkage at Temecula; the focus of wildlife-crossing restoration the project cuts against.
Imperial Valley
the desert region (and Imperial Valley Substation near El Centro) where the line begins; the source of the remote solar/geothermal/wind it is meant to carry.
Murrieta
city adjacent to Temecula; one of the valleys overlying the Temecula Valley Groundwater Basin. [18]
North of SONGS Substation
the proposed new substation near the San Diego/Orange county coast that is the line's western endpoint; retained by Horizon West.
Orange County
part of SDG&E's service territory and the western-endpoint region — one of the counties the line benefits, unlike Riverside.
Palomar Range
the Palomar / Peninsular Ranges east of I-15; the inland mountain block of the Santa Ana–Palomar wildlife linkage.
Pauba Valley
the sub-valley of the Temecula Valley basin where RCWD banks groundwater recharge — drinking water directly beneath the Temecula Creek alluvium the towers would bore. [18]
Rainbow Canyon
area at the Temecula/San Diego county line near the I-15 wildlife-crossing site.
San Diego County
SDG&E's core service territory and the project's destination region.
Santa Ana Mountains
the coastal mountain block west of I-15; home to the isolated Santa Ana mountain-lion population that depends on the severed linkage.
Santa Ana–Palomar Mountains Linkage
the critical, already-pinched wildlife connection between the Santa Ana and Palomar ranges, severed by I-15 at Temecula; Temecula Creek is its strand.
Santa Margarita Ecological Reserve (SMER)
~4,334 acres of protected middle-course lands managed by SDSU with BLM, CDFW, and The Nature Conservancy.
Santa Margarita Estuary
the ~192-acre estuary at Camp Pendleton where the river meets the Pacific; a CWA 303(d)-impaired water and listed-species refuge.
Santa Margarita River
one of Southern California's last free-flowing rivers (~29 miles); critical habitat for the federally endangered Southern California steelhead; fed by Temecula Creek. [28]
Santa Margarita River Trail Preserve
a 1,384-acre preserve (established 2018) protecting a 5-mile river stretch.
SONGS
San Onofre Nuclear Generating Station; the retired coastal nuclear plant near the line's western endpoint and the project's "North of SONGS" reference point.
SR-79 South
State Route 79 South; the Temecula-area corridor (toward Aguanga/Vail Lake) the route parallels; rural parcels here may have private wells.
Temecula Creek
the ~5-mile creek segment the line crosses; an MSHCP Core Area (5,663 acres), arroyo-toad and least Bell's vireo habitat, and a tributary of the Santa Margarita over a shallow drinking-water aquifer.
Temecula Valley
the contested valley region; the largest of the valleys overlying the groundwater basin of the same name. [18]
Temecula Valley Groundwater Basin
DWR Bulletin 118 Basin No. 9-05 (87,800 acres); the adjudicated drinking-water aquifer under Temecula Creek, exempt from the state groundwater act. [16][18]
Vail Lake
reservoir/recharge feature in the upper Temecula Creek watershed, near the route's eastern approach.
Vail Ranch Middle School
a school in the corridor's vicinity, cited as a sensitive receptor near the 500 kV alignment.

Species

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Arroyo toad
federally endangered toad that breeds in the shallow, sandy stream pools of Temecula Creek; a hard Endangered Species Act trigger for any crossing. [8]
Least Bell's vireo
federally endangered, riparian-obligate songbird documented nesting in the willow/cottonwood thickets along Temecula Creek. [8]
Quino checkerspot
federally endangered butterfly of the region's chaparral/coastal-sage; an MSHCP-covered species in the corridor's bioregion. [8]
Santa Ana mountain lion
the I-15-isolated mountain-lion population whose survival depends on the Santa Ana–Palomar linkage Temecula Creek carries; listed threatened under the state Endangered Species Act (2026).
Southern California steelhead
federally endangered sea-run trout; the Santa Margarita River (fed by Temecula Creek) is its designated critical habitat and a top recovery priority. [28]
Southwestern pond turtle
the region's only native freshwater turtle; a California Species of Special Concern that USFWS proposed listing as threatened in 2023 (not finalized) — properly framed as "proposed," not "endangered."

Acronyms & Technical / Legal Terms

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AB 1373
2023 law (added Public Utilities Code §1001.1) setting the conditions under which a CAISO-approved line is presumed needed, including "most cost-effective" and "no substantial change to cost." [24]
AB 2292
2024 law (SDG&E a registered supporter) that repealed the CPUC's duty to weigh cost-effective alternatives (§1002.3) before approving a transmission line. [23]
ACCC
Aluminum Conductor Composite Core; a low-sag, high-capacity conductor that can raise an existing line's capacity (reconductoring) instead of building new towers.
Adjudicated basin
a groundwater basin whose pumping rights are fixed by a court decree and run by a court-appointed Watermaster; exempt from the state groundwater act. The Temecula Valley basin is one. [16]
Averch–Johnson effect
the documented tendency of a rate-of-return-regulated utility to over-invest in capital ("gold-plating") because profit scales with what it builds.
CAISO participation adder
a FERC Order 679 bonus (about 0.5% on return) for belonging to a grid operator like CAISO; a federal court denied it to SDG&E. [6]
CEQA
California Environmental Quality Act; the state environmental-review law; requires an Environmental Impact Report (EIR) before a project like this is approved. [1]
CESA
California Endangered Species Act; the state take-prohibition/permitting counterpart to the federal ESA. [9]
Cone of depression
the cratered drawdown of the water table around a pumped well or dewatered excavation; how construction dewatering can lower neighboring wells. [27]
Construction General Permit
the statewide NPDES permit covering construction stormwater and dewatering discharges (including pumped groundwater from foundations). [20]
CPCN
Certificate of Public Convenience and Necessity; the CPUC permit a utility must obtain to build the line — the core state approval to contest. [3]
Critical habitat
habitat formally designated under the Endangered Species Act as essential to a listed species' recovery; designation along the alignment heightens review. [8]
CWA §401
Clean Water Act Section 401; the state water-quality certification (RWQCB) required for a federally permitted activity affecting waters. [11]
CWA §404
Clean Water Act Section 404; the U.S. Army Corps permit for discharging dredged or fill material into waters of the U.S. (creek crossings). [10]
CWIP
Construction Work In Progress; a FERC incentive (Order 679) letting a utility earn a return on a line before it is finished. [6]
Dewatering
pumping groundwater out of an excavation to build a foundation below the water table; temporarily lowers the local water table (a "cone of depression"), and the discharge is permit-regulated. [27]
Discovery
the formal data-request process in a CPUC proceeding — the mechanism to pry loose the models and maps behind the "need" case.
Drilling slurry
the bentonite or polymer "drilling mud" that holds a deep bore open below the water table; by design it is pressurized into the surrounding aquifer before tremie concrete displaces it. [27]
EHV
extra-high-voltage; transmission at 345 kV or above. 500 kV (the IV-NoS voltage) is EHV used for long-distance bulk power transfer.
EIR
Environmental Impact Report; the detailed environmental study CEQA requires before a project is approved — the central document to shape via scoping comments. [1]
EIS
Environmental Impact Statement; the federal (NEPA) equivalent of an EIR, required when there is a federal action or permit. [2]
Eminent domain
the government/utility power to take private property (or an easement) for public use with compensation; the threat behind survey-access and right-of-way demands.
ESA
Endangered Species Act; the federal species-protection law; §7 requires consultation and §10 permits mitigated "incidental take." [8]
Ex parte
restricted off-the-record communications with CPUC decision-makers; the rules govern who may lobby the Commission and how.
GO 95
CPUC General Order 95; the rules for overhead electric-line design and construction (clearances, pole setting, loading) — the framework, not engineered caisson depth. [4]
GO 131-E
CPUC General Order 131-E (2025); the transmission-permitting rule that adds a rebuttable presumption of need for CAISO-approved projects and narrows the alternatives analysis. [5]
Incidental take
Endangered Species Act / CESA authorization to harm a listed species during otherwise-lawful activity, if mitigated. [8]
Intervenor compensation
the CPUC program that can reimburse a qualifying party's expert and legal costs from ratepayer funds — a way to fund the fight.
IRP
Integrated Resource Plan; the CPUC's portfolio choice of which resources (and where) the grid will procure — the administrative step that feeds CAISO's "need."
IV-NoS
Imperial Valley–North of SONGS; the project's official regulatory name in CAISO/CPUC/FERC dockets (marketed by SDG&E as "Golden Pacific Powerlink").
Just and reasonable
the federal legal standard (FERC) a transmission rate must meet; a rate that isn't just-and-reasonable is unlawful — the hook for contesting the line's cost and return. [26]
kV
kilovolt (1,000 volts). This line is 500 kV (500,000 volts) — extra-high-voltage for bulk transfer.
Lattice steel tower
a four-legged steel-truss transmission tower (here 80–200 ft tall), each leg on its own drilled concrete pier.
Liquefaction
the loss of soil strength when loose, saturated sand is shaken in an earthquake; a reason creek-crossing foundations must be driven deeper into competent ground. [27]
MSHCP
Western Riverside County Multiple Species Habitat Conservation Plan; the federally permitted conservation plan (146 covered species, ~500,000-acre reserve); Temecula Creek is a Core Area. [14]
Need
the threshold question of whether the grid actually requires the line; GO 131-E now presumes need for CAISO-approved projects, shifting the burden to opponents (rebuttable, especially on cost).
NEPA
National Environmental Policy Act; the federal environmental-review law (its study is an EIS); applies when there is a federal action or permit. [2]
Non-wires alternative
a solution that meets a grid need without a new line: efficiency, local solar-plus-storage, or reconductoring; the comparison AB 2292 stripped from the CPUC's duty.
NPDES
National Pollutant Discharge Elimination System; the Clean Water Act permit program (state-administered here) for discharging pollutants to surface water, including dewatering discharge. [19]
Party status
formal standing in a CPUC proceeding (the right to file, conduct discovery, and appeal) — the entry ticket to the fight.
PEA
Proponent's Environmental Assessment; the environmental document the utility files with its CPCN application that seeds the CPUC's EIR; not yet filed for this project.
Policy-driven
CAISO's classification for a line justified by state clean-energy policy (carrying remote renewables) rather than reliability or congestion — IV-NoS's category.
Porter-Cologne
the Porter-Cologne Water Quality Control Act; California's foundational water-quality law; basis for Waste Discharge Requirements and protection of "waters of the state." [13]
Protest window
the roughly 30-day period after the application is filed in which parties can formally protest and request hearings — a key calendar deadline.
PSPS
Public Safety Power Shutoff; preemptive de-energizing of lines in high fire-risk weather; cuts power (including rural electric well pumps) during exactly the red-flag windows.
Rate base
the utility's pile of long-lived investment (towers, wires, substations) on which it earns its return; a bigger rate base means bigger profit. [26]
Reconductoring
upgrading an existing line with higher-capacity conductor (e.g. ACCC) to add capacity without a new corridor — a lower-impact, "non-wires" alternative.
Right-of-way (ROW)
the strip of land (here 250 ft or more) a utility secures (by easement or eminent domain) to build and maintain a line; no permanent structures are allowed within a 500 kV ROW.
ROE
Return on Equity; the FERC-set percentage profit a utility earns on the equity in its transmission rate base — the line's profit engine. [26]
RPS
Renewables Portfolio Standard; the percentage-of-retail-sales clean-energy mandate ratcheted up by SB 1078 → SB 350 → SB 100 → SB 1020. [22]
SB 100
the 100 Percent Clean Energy Act of 2018: 60% RPS by 2030, 100% clean electricity by 2045; the policy CAISO cites for "policy-driven" lines. [21]
SB 1020
2022 law adding interim clean-energy targets (90% by 2035, 95% by 2040) on the path to SB 100's 100%. [22]
Scoping
the early EIR phase that sets which impacts and alternatives the environmental review must study — the highest-leverage moment to file comments. [1]
Scour
the erosion of a streambed during high flow; scour-prone tower foundations must be buried below the 100-year scour depth (not raised "chimneys"). [27]
SGMA
Sustainable Groundwater Management Act (2014); the state groundwater-management law. Adjudicated basins like Temecula Valley are exempt from its plan process. [15]
Storage as transmission
using batteries (or reconductoring) to defer or replace a new transmission line — a cost-competitive alternative the campaign presses.
TAC
Transmission Access Charge; the CAISO-wide charge through which a transmission owner's FERC-set return is recovered from all ratepayers in the CAISO footprint (why Temecula helps pay for a line that serves San Diego/LA). [25]
Tariff §24
the CAISO tariff sections governing competitive project-sponsor selection (§24.5) and assignment (§24.6) — the process that picked Horizon West and let it hand the line to SDG&E.
TO6
SDG&E's FERC transmission-owner rate case (the settlement setting its current ROE and equity ratio).
Transmission Plan
CAISO's biennial Transmission Planning Process (TPP), where projects are approved (IV-NoS in the 2022–2023 cycle) and can be reassessed or cancelled on cost.
Transmission vs. distribution
transmission is high-voltage bulk power (FERC-regulated, recovered via the TAC); distribution is local lower-voltage service (CPUC retail rates). The profit and rate mechanics differ.
Undergrounding
burying a line instead of overhead towers (5–10× the cost); a remedy communities have forced (e.g. Chino Hills), not something the utility chooses.
Water table
the depth below ground at which soil is saturated (groundwater); shallow (~10–30 ft) along Temecula Creek, so foundation bores reach it. [18]
WDR
Waste Discharge Requirements; the RWQCB permit (under Porter-Cologne) for discharges that affect water, including construction dewatering not covered by an NPDES permit. [13]

Sources

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  1. [1]CEQA Guidelines — Appendix G & the CEQA statute — California Natural Resources Agency
  2. [2]What is the National Environmental Policy Act (NEPA) — U.S. EPA
  3. [3]California Public Utilities Code §1001 (Certificate of Public Convenience and Necessity) — California Legislature
  4. [4]CPUC General Order 95 (overhead line construction), Rule 49.1 — CPUC
  5. [5]CPUC General Order 131-E (adopted by D.25-01-055) — CPUC
  6. [6]FERC Order No. 679 (transmission incentives) — Federal Energy Regulatory Commission
  7. [7]FERC Order No. 1920 (long-term regional transmission planning) — FERC
  8. [8]Endangered Species Act (ESA) — U.S. Fish & Wildlife Service
  9. [9]California Endangered Species Act (CESA) — California Department of Fish & Wildlife
  10. [10]Overview of Clean Water Act Section 404 — U.S. EPA
  11. [11]Clean Water Act Section 401 Water Quality Certification — U.S. EPA
  12. [12]Lake and Streambed Alteration Program (Fish & Game Code §1602) — CDFW
  13. [13]Porter-Cologne Water Quality Control Act — State Water Resources Control Board
  14. [14]Western Riverside County MSHCP — Regional Conservation Authority
  15. [15]Sustainable Groundwater Management Act (SGMA) — California Department of Water Resources
  16. [16]Adjudicated Areas (SGMA) — California Department of Water Resources
  17. [17]Santa Margarita River Watershed Watermaster — Chronology (US v. Fallbrook PUD)
  18. [18]California's Groundwater (Bulletin 118) — Temecula Valley Groundwater Basin (No. 9-05) — California Department of Water Resources
  19. [19]National Pollutant Discharge Elimination System (NPDES) — U.S. EPA
  20. [20]Construction General Permit (Order 2022-0057-DWQ) — dewatering guidance — State Water Resources Control Board
  21. [21]SB 100 (The 100 Percent Clean Energy Act of 2018) — California Energy Commission
  22. [22]Renewables Portfolio Standard (RPS) Program — CPUC
  23. [23]AB 2292 (2024) — repeal of Public Utilities Code §1002.3 — California Legislature
  24. [24]AB 1373 (2023) — Public Utilities Code §1001.1 (need-presumption conditions) — California Legislature
  25. [25]Electric Transmission Rates and FERC Proceedings (the Transmission Access Charge) — CPUC
  26. [26]Cost-based rates / return on equity (FERC transmission revenue requirement) — Federal Energy Regulatory Commission
  27. [27]Drilled Shafts: Construction Procedures and LRFD Design Methods (FHWA-NHI-10-016) — U.S. Federal Highway Administration
  28. [28]Southern California Steelhead (Oncorhynchus mykiss) — NOAA Fisheries
  29. [29]Rancho California Water District
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