ALH

ALH units must always be operated in Flow Mode.

The Local Operating Order (LOO) SE3.

The 60 Second Acknowledge Setpoint Timer: After adjusting a unit flow setpoint, remote operators have 60 seconds to click Initiate or the change will revert to the previous number and nothing will happen.

The 2 Minute Synchronization Timer: After unit start is initiated, ALH units must remain in SNL for 2 minutes before they can be synchronized.

The 5 Minute Loading Timer: Once a unit is synched to the system the operator must enter a flow setpoint within 5 minutes or else risk having to wait 24 minutes for the channel stability timer to reset.

The 10 Minute Timer Flow Restoration Timer: Plant Operators have 10 minutes from the time a unit trips to re-establish flow by whatever means is appropriate for the particular circumstance (unit re-sync or HLK gate movement).

The 24 Minute Channel Stability Timer: The Channel Stability timer will limit remote operators to one unit start or flow increase per 24 minutes. Unit stop and flow decrease is always possible. Studies conducted have found that adjustments to unit discharge when the forebay level is below 433m can cause excessive disturbance in the approach channel and that the water will settle sufficiently after 24 minutes.

• • The 60 Second Acknowledge Setpoint Timer: After adjusting a unit flow setpoint, remote operators have 60 seconds to click Initiate or the change will revert to the previous number and nothing will happen.
• • The 2 Minute Synchronization Timer: After unit start is initiated, ALH units must remain in SNL for 2 minutes before they can be synchronized.
• • The 5 Minute Loading Timer: Once a unit is synched to the system the operator must enter a flow setpoint within 5 minutes or else risk having to wait 24 minutes for the channel stability timer to reset. This would only be of concern if the forebay was below 433m since there would no 24 minute restriction if it was above 433m.
• • The 10 Minute Timer Flow Restoration Timer: Plant Operators have 10 minutes from the time a unit trips to re-establish flow by whatever means is appropriate for the particular circumstance (unit re-sync or HLK gate movement).
• • The 24 Minute Channel Stability Timer: When the forebay is below 433m the Channel Stability timer will limit remote operators to one unit start or flow increase per 24 minutes. Unit stop and flow decrease is always possible. Studies conducted have found that adjustments to unit discharge when the forebay level is below 433m can cause excessive turbulence in the approach channel and that the water will settle sufficiently after 24 minutes.

• Only one of either a unit start or flow setpoint increase will be allowed while the 24 minute timer is active; however, unit stop and flow setpoint decreases are always possible.
• Remotely, the timer is indicated by “Ramp in Progress” on the remote ALH SCADA unit screen. Locally the timer is shown on the Unit Control screen.

Restart delays greater than 10 minutes may result in environmental emergencies due to fish stranding in the reduced water levels in the Columbia River down stream of HLK.

The ALH Control Room should be attempted first, followed by FortisBC. Fortis is responsible for ALH operator callout.

• SE3
• A07
• 4T-ALH-01

• 0600 - 1600 during weekdays.
• 0800 - 1600 during weekends and statutory holidays.
• If an unrecoverable trip happens during normal staff hours, HLK lock-keepers should be contacted immediately to restore flows by operating the HLK gates.
• If an unrecoverable trip happens outside of normal staff hours, RGO should be initiated immediately and lock-keepers contacted secondarily.
• Lock-keepers should be informed anytime RGO is used.

Restore water flow within 10 minutes. First attempt a unit re-synch (check with Grid 1 to make sure the line is energized). If unit(s) are unrecoverable, either call the lockkeeper or initiate RGO (depending on the day and time).

Grid 1. Make sure that it is okay to close the unit breakers.

• • Arrow Lakes Hydro generating station is owned by Arrow Lakes Power Corporation (ALPC), an IPP.
• • Adjacent to the station, the Hugh Keenleyside Dam is owned by BC Hydro and operated by BC Hydro lock-keepers.
• • Energy is fed into the FortisBC system at 230kV via the ALPC owned 2L290. Operating authority and responsibility for 2L290 are assigned to FortisBC.
• • FortisBC dispatches ALH operators and electricians.

No. Leave the unit(s) in SNL. Anytime there is a trip with the forebay below 433m, flows should be restored by other means than re-synchronization since the channel stability timer (24 minutes) will be in effect. Depending on the day and time, call the lock-keeper or initiate RGO. In either case, inform Fortis of the occurrence once corrective action has been initiated.

The unit(s) should be left in SNL until the ALH operator can attempt a re-sync. If units are left in SNL for more than an hour they will automatically shut down.

Yes. If it is possible to re-sync the units, check that the line 2L290 is ready and bring the units back one at a time. This means that if 2 units have tripped to SNL, synchronize one unit and bring it up to pre-disturbance flow then do the same with the other unit. Inform Fortis of the occurrence once corrective action has been initiated.

A comparison of the canal forebay elevation / turbulence compared to scroll-case pressure is done and may cause a unit trip. This is called Gross Trip which is headloss protection that will result in an 86N.

ALH does not have black start capability.