Treatment Process

 

Water 

It’s something we often take for granted – clean, safe drinking water that comes out of a tap.  Water is essential to our survival, and although water is naturally all around us in waterways, it must be treated to remove dirt, bacteria, and other harmful elements to humans.

Aquatera's water treatment facility has a designed capacity with an average daily flow of 20 million liters/day (MLD) with a maximum capacity of 52 million liters/day (MLD).

The Treatment Process includes:

  • Pre-settling
  • Coagulation
  • Flocculation
  • Sedimentation
  • Filtration
  • Fluoridation
  • Chlorination

Prepare yourself - this is where things get technical.

 

Chemicals are added to the water supply to aid coagulation, disinfection, and fluoridation.

  • Liquid PAC (poly aluminum chloride) and an anionic polymer are added to the plant influent for coagulation. This results in small particles gathering together by their electric charge. The particles are removed from the water during these processes.
  • Chlorine is added to the filter influent for the prevention of bacterial growth in the filters, and the plant effluent (potable water) for disinfection.
  • Hydrofluosilicic acid is added to the plant effluent to ensure adequate fluoride levels in the water supply. Fluoride’s only purpose in our water supply is for dental protection, and we must add fluoride to meet specific requirements outlined in our license with Alberta Environment.

During this process, color and some trace minerals are also removed.

 

The Wapiti River has always been Aquatera’s water source.  River water is pumped into storage ponds, (which allows natural sedimentation of dirt) located across from our raw water pump station at the Wapiti River. The raw water is then pumped to the water treatment facility for further processing.

Coagulation of turbidity (suspended and colloidal particles) is undertaken in two steps.

  1. The first consists of "flash" mixing of the raw water with the PAC (poly aluminum chloride) and then later with the anionic polymer in the rapid mix tank.
  2. The second step involves the gentle mixing (flocculation) of the raw water and process chemicals to form larger, heavier and more settleable particles (floc).

Removal of the floc occurs in the sedimentation tanks where the floc settles to form sludge. The sludge is withdrawn from the bottom of the tanks, then sent for removal at our wastewater treatment facility (one of the benefits of having our water/wastewater facilities next to each other.)  The resulting clarified water is chlorinated just before it enters the filters.

Filtration involves the passing of the clarified water through a sand/coal media to remove the remaining particulate matter. When the filters become dirty, they are "backwashed" with previously filtered water and the dirty backwash water is pumped to the wastewater treatment facility for removal of this inorganic material.

The filtered water passes into a clear well located directly beneath the filters from which it is piped to the adjacent 9 million litre reservoir.

From this reservoir, the potable water is pumped by the high lift pumps into the Aquatera's distribution system for consumption by our customers, and to hydrants for firefighting.

 

Process Control:

Treatment processes are controlled by computers located in the process buildings.

Operators can optimize the operations of the treatment processes from a computer in the control room that is linked to the logistic computers. The process can also be controlled manually by the operator from the equipment locations.

 

Lab Analysis:

Operators perform numerous lab analyses to monitor process control.

Our Alberta Environment operations approval requires us do many various tests for the continuous control of operations and to maintain records of plant performance. Samples are collected continuously from the water treatment facilities for analysis.

We do many other various tests outside of our approval for process optimization and control.

Water analysis includes tests for:

  • Turbidity
  • Color
  • PH
  • Alkalinity
  • Hardness
  • Dissolved solids
  • Fluoride, Raw and Potable
  • Residual Free and Total chlorine
  • Jar testing
  • Microbiological
  • Particle counts
  • Full Spectrum Water Analysis (sent out for testing)
  • Etc.

Additionally, samples are sent to Alberta Environment's laboratory on a monthly basis for more extensive analysis and to confirm the results obtained on site.