Manage a blue-green algae alert and complete the spring dam surveillance inspection

You are the catchment and storages officer reporting to the Catchment and Storages Manager.

Simulated workplaceAdvanced missionCAQA ClearFlow Water

What is going on

The raw water storage sample from the offtake tower has returned 14,000 cells per millilitre of Microcystis, placing the storage at the alert level of the blue-green algae response framework, with warm weather forecast. The offtake has been moved to the lower level and the Kialla plant is running enhanced coagulation with powdered activated carbon on standby. At the same time the spring surveillance inspection of the embankment dam is due, including piezometer and seepage weir readings, and the last inspection noted a wet patch at the downstream toe near the left abutment. The Catchment and Storages Manager wants both matters managed and documented this week.

Hamish Dunlop, Catchment and Storages Manager
Subject: Algae count rising in the storage and the spring dam inspection

Yesterday's sample from the offtake tower came back at 14,000 cells per millilitre of Microcystis, which puts the storage at the alert level, and the weather is warming. I need the blue-green algae response started: confirm the count with a second sample, decide the offtake depth with the plant, brief the control centre and prepare the notification to the health regulator if it reaches the next level. The spring surveillance inspection of the embankment is also due this week, so plan to walk the dam with me, read the piezometers and seepage weir and write up the inspection report.

Your brief

Run the blue-green algae alert response, including confirmation sampling, offtake and treatment liaison, control centre briefing and a draft notification for the health regulator, and carry out and report the spring embankment dam surveillance inspection with instrumentation readings and any dam safety actions.

Work through it

You do not need to do it all. Doing a few of these will show you what the work is like. Your ticks and notes stay on this device.

Read the Drinking Water Quality Risk Management Plan sections on hazards and preventive measures and the Environmental Management Policy, and state the algae alert levels and the actions each level triggers.
Arrange a confirmation sample at the offtake tower and a surface sample near the intake under a work near water permit, and record both in the Water Quality Sampling Register.
Liaise with the Water Treatment Manager on the offtake depth, the enhanced coagulation and the trigger for powdered activated carbon, and record the agreed operating settings.
Brief the control centre on the alert, the sampling schedule and the escalation triggers, and update the notice for staff and the public.
Draft the notification to the health regulator that will be sent if the count reaches the next level, stating the cell count, the toxin sampling arranged and the treatment barriers in place.
Walk the embankment with the Catchment and Storages Manager and inspect the crest, upstream face, downstream face, toe, abutments, spillway and outlet works, recording observations and photographs against the surveillance checklist.
Read the piezometers and the seepage weir, compare them with the previous readings and the trend record, and assess whether the wet patch at the left abutment toe has changed.
Write the dam surveillance inspection report with any dam safety actions, their urgency and owner, and enter any deficiency as a hazard in the WHS and Environmental Incident Register.

My notes: what did I enjoy, and what surprised me?

What someone in this role would produce

Algae alert action record with sampling entries and treatment liaison notes
Control centre briefing and updated public notice
Draft health regulator notification
Dam surveillance inspection report with instrumentation readings
Any hazard entries raised in the incident register

Printing this is a record of what you explored. It is not a certificate or a qualification.