Water Treatment & Distribution

The Town of Milk River maintains a high quality water treatment system with surface water supply from the Milk River, meeting and exceeding all requirements set by Alberta Environment and other regulatory agencies.  The Town of Milk River prides itself on our clean, clear and safe water.

 

The water treatment process begins with a trip from the Milk River through the Town’s ‘infiltration galleries’ where the water is filtered for larger particles prior to entering the system.

 

Next, the Town’s ‘Lift Station’ pumps the water to a ‘Sedimentation Basin’ to further filter the water, at which point the water is then divided into two ‘Slow Sand Filters’ for even more filtering.

 

The water is finally pumped into the ‘Water Treatment Plant’ where it is treated and directed into a ‘Detention Tank’. When flowing into the Detention Tank the filtered water is treated with chlorine and fluoride and then, after the required contact time, the water is pumped into the distribution system so residents can enjoy the finished product.

 

90% of the Town’s distribution system is supplied by gravity pressure, and the remaining 10% is supplied via booster pumps at pressures varying from 65 to 80 PSI. These lines also supply the local fire hydrant system with pressure to meet the requirements of the Fire Department.

 

For a more detailed explanation of the water treatment system, please contact Milk River Public Works.

 

 

Raw Water Lift Station:

The raw water lift station is fed by a gallery system consisting of 7 notched pipes lying across the river under the bed. The river water flows into a wet well were two variable speed 75hp vertical turbine pumps are ready to pump water up to the sedimentation basin. The variable speed is required to maintain the diversion rates set by AB environment, as well as the soft start and shut down of the pumps to prevent water hammer in the pipes.

 

Sedimentation Basin:

The raw water is pumped in the sedimentation basin where the flow is slowed down across the basin and over a weir system to settle out turbidity before it is divided into the two slow sand filters. Copper sulphate is added manually from the WTP when raw water pumps are filling the sedimentation basin to control algae. Between the sedimentation basin and filer bed two water co-ops receive their water.

 

Filter Beds:

Each slow sand filter has a capacity of 210 M3 per hour or 3500 lpm. The filters are made up of a layer of sand about 1 meter deep with various graduation of washed rock on top of a network of under drain piping.

 

Ripening:

The unfiltered water flows through the sand during the ripening process to create the top layer called schmutzdecke (an intense layer of microbes) This layer lives by consuming whatever is passing through in the water, which is responsible for removing bacteria, viruses, Giardia, Criptosporidium, and parasites through predation. As the water passes through the deeper layers of sand further filtration is done. After the filter is ripened the water is then directed to detention tank.

 

Finished Water:

The discharge piping from each filter is connected to and end suction centrifugal pump that limits the filtration rate to 3,500 lpm. The operator can choose what ever rate he wants up to this 3,500 lpm, the town usually runs the pumps between 1500 lpm and 2500 lpm for the best results. The filtered water is treated with chlorine and fluoride through automated injection equipment after Chlorine and fluoride are injected the filtered water is enters the 1.4ML detention tank.

 

Distribution:

From the detention tank water enters the distribution system to supply residents of the community. 90% of the distribution system is supplied by gravity pressure and 10% is supplied by booster pump pressure from the town’s booster station.

 

Sewer Collection:

The sewer is collected in a network of main and service lines throughout the town. The network of piping lead the sewer to a sewage lift station were it is lift so gravity can take over again to get the flows out to the sewer lagoons.

 

Sewer lagoons

The sewer flows into a lagoon system that consists of 3 anaerobic ponds that run in series where anaerobic bacteria digest the solids then to a facultative pond and evaporation pond where further aerobic bacteria treatment is being accomplished.