OPALCO update on redundancy, cable removal

  • Fri Aug 4th, 2017 1:30am
  • News

The following is from OPALCO’s online newsletter.

OPALCO has full redundancy to manage power outages

It’s easy to see the correlations between the island communities in North Carolina and the San Juan Islands, who are dependent on seasonal tourism and surrounded by water.

Last Thursday, two island communities in North Carolina lost power after their major underground transmission lines were cut in a construction project. There was no redundancy in place to re-route power and thousands were evacuated. It will take weeks to repair the line.

This is seriously impacting the lives of many in these communities.

OPALCO recognizes how critical reliable power is for our island communities – for safety, economic development and for our quality of life. OPALCO’s made redundancy in our transmission system a top priority and there are two submarine cables in all major island crossings.

With this redundancy, and the ability to remotely control our system through fiber optics, OPALCO can re-route the power transmission throughout San Juan County to keep the power on if a cable fails or breaks.

“OPALCO’s transmission system is incredibly robust,” according to OPALCO’s system engineer Joel Mietzner. “All the transmission (High Voltage) lines on land are run overhead for ease of maintenance and quick repair.”

The 2017 Submarine Cable project between San Juan Island and Lopez replaces the 1977 cable and will provide redundancy if the other submarine cable in this crossing fails or requires service. The benefits of this project will offer state of the art transmission lines with unparalleled protection – as well as real-time monitoring via fiber – to keep the San Juan Islands connected to the mainland for the next 50+ years. Just another step to ensuring our quality of life is maintained in our unique island communities.

Cable removal finally at hand

OPALCO has been closely monitoring CenturyLink’s project to replace their submarine fiber cable in the San Juan to Lopez crossing – the same crossing where OPALCO will replace its 1977 submarine cable in September. The two agencies have worked side by side to prepare the cable landings and terminals on both shorelines. This past week, contractors installed and activated the new fiber communications cable for CenturyLink and work to pull up the old cable begins today.

There is still cause for concern as the old CenturyLink cables are retrieved. There are multiple sections of abandoned cable in the crossing where CenturyLink has previously left cables in place during emergency repairs. Their cables cross over OPALCO’s existing cable – currently the sole active transmission line – in several locations. The frayed condition of their old cables may snag OPALCO’s cable as they are pulled up. Damage to OPALCO’s transmission line in that crossing would cause costly project delays and could cause power outages on San Juan Island. OPALCO’s system engineer will be on site for the cable retrieval and a Remote Operated Vehicle (ROV) fly over (underwater) of the sections where entanglement is a concern to ensure that the existing OPALCO cables are not damaged.

OPALCO’s submarine cable project is on right on schedule:

• Site preparations are complete at the Lopez and San Juan shoreline terminals.

• The new Sumitomo submarine cable is in transit from Japan by barge and is scheduled to arrive on Aug. 15.

• Work barges and tugs will start arriving Sept. 5 for the scheduled retrieval of the old cable, closely followed by the installation of the new 2017 submarine cable.

There is still time to enter OPALCO’s “Name the Submarine Cable” contest and win one of eight golden tickets to witness the 2017 submarine cable installation up close. Enter here: https://www.opalco.com/power-system/submarine-cables/