Project

600 MW of cross-border clean-energy transmission, under the Strait.

A purpose-built submarine link between Port Angeles, Washington and a landfall near Victoria, British Columbia — buried beneath the seabed across the Strait, continued underground on each shore. Initially energized as a 600 MW HVAC 230 kV interconnection between BPA and BC Hydro, engineered from the outset for conversion to HVDC voltage-source converter (HVDC-VSC) technology as a future upgrade.

The route

From Port Angeles to a landfall near Victoria.

The cable corridor runs roughly 30 miles, leaving the U.S. shore in Port Angeles, Washington, crossing beneath the Strait of Juan de Fuca, and making landfall near Victoria on Vancouver Island. Most of that distance is submarine, with the cable buried beneath the seabed via subsurface trenching. Intertidal and nearshore zones are crossed via horizontal directional drilling — a no-trench, low-disturbance technique that protects sensitive shoreline ecosystems.

On each end, endpoint substations tie the cable into the local high-voltage AC transmission system: Bonneville Power Administration's network on the U.S. side, and BC Hydro's network on the Canadian side. Initial energization uses HVAC 230 kV transformation and switchgear; the planned HVDC conversion later swaps the endpoint stations for voltage-source converters without disturbing the buried cable itself. The endpoints, route corridor, and interconnection specifications were all defined and approved during the original development phase.

Map of the Strait of Juan de Fuca showing the proposed cable route in red between Port Angeles, Washington and a landfall near Victoria, British Columbia. — Cable corridor as defined during the original project development phase.

Cross-section diagram showing the undersea cable route between Port Angeles and View Royal/Victoria with endpoint stations on each shore, horizontal drilling through intertidal zones, and subsurface trenching across the Strait of Juan de Fuca seabed. — Cross section
From endpoint substation to seabed and back.
The cable transitions from each endpoint substation through subsurface trenching to a horizontal-drilled crossing of the intertidal zone, then continues across the Strait floor under the protective cover of the seabed itself. Initial energization uses HVAC 230 kV transformation and switchgear; the planned HVDC conversion later swaps the endpoint equipment for voltage-source converter stations without disturbing the buried cable.

Technology roadmap

HVAC first. HVDC later. Both by design.

The revival adopts a phased approach: energize the corridor first as a 600 MW HVAC 230 kV interconnection to deliver cross-border transmission capacity as quickly as possible, then convert to HVDC once operating experience and market conditions warrant it. Both endpoints are engineered from the outset to accommodate the later conversion — the buried cable corridor itself is unchanged across phases.

Phase 1 — HVAC 230 kV interconnection

Initial energization uses standard high-voltage AC transformation and switchgear at each endpoint. Because BPA and BC Hydro both operate synchronously within the Western Interconnection, a 230 kV AC tie integrates directly into both systems, delivering 600 MW of firm cross-border transmission capacity from the day the corridor is energized. Faster to build than a Day-1 HVDC installation, lower first-phase capital, and immediately usable for market and reliability purposes.

Phase 2 — HVDC conversion

Conversion to HVDC voltage-source converter (HVDC-VSC) technology later in the asset life replaces the AC endpoint equipment with converter stations, without disturbing the buried cable itself. This unlocks fully controllable real- and reactive-power flow, seconds-scale bi-directional dispatch, and black-start capability into either grid — the operational profile of a modern DC interconnection.

Route and burial are unchanged across phases

The physical corridor is identical for both phases: ~35 km buried beneath the seabed, ~14 km buried underground on land, with horizontally drilled shore approaches emerging ~800 m offshore. The cable and its ecological footprint do not change when the conversion happens; only the endpoint stations do. The ecological, permitting, and land-use commitments made in the original development phase carry forward intact.

Two mature technologies, not one frontier

230 kV submarine AC cables are widely deployed in cross-border and inter-utility interconnections worldwide. HVDC-VSC has been proven at commercial scale in dozens of installations — Gotland, DirectLink, Murraylink, CrossSound, and many subsequent projects. The phased approach combines two mature technologies rather than betting the initial energization on a single frontier design.

At a glance

Project specifications.

Initial capacity: 600 megawatts, cross-border
Financing: Privately financed — at no cost to energy ratepayers or taxpayers
Initial energization: HVAC at 230 kV — synchronous interconnection between the BPA and BC Hydro systems
Planned upgrade: Conversion to HVDC voltage-source converter (HVDC-VSC) technology — adds fully controllable real- and reactive-power dispatch, seconds-scale flow control, and black-start capability
Length: Approximately 49 km (≈30 mi) total — ~35 km buried beneath the seabed, ~14 km buried underground on land
Route: Port Angeles, WA ↔ landfall near Victoria, BC
US interconnection: Bonneville Power Administration system
Canadian interconnection: BC Hydro (formerly BCTC) system
Marine burial: Sea-plow or ROV-jet trenching to ~1–1.5 m below the seabed; concrete mattresses where bedrock prevents burial
Shore approach: Horizontal directional drilling at each landing — drill hole emerges ~800 m offshore, leaving the intertidal zone undisturbed
Land burial: Direct-buried in a ~1 m wide trench at ~1 m depth, fully backfilled
Construction duration: Approximately 24 months from financing close (per original development plan)

Discuss the technical foundation.

The original engineering, environmental, and interconnection work is documented in detail. We're happy to share the relevant materials with serious investors, agencies, and partners.

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