How does all this work?

What is the system capacity (how many homes, businesses, institutions will be served)? 

• The water supply system used the design criteria outlined in Indigenous Services Canada policies and guidelines.

• The water distribution system has the capacity to provide potable (drinking) water for the 20-year maximum day demand at 21 L/s and a fire flow of 100 L/s at the current school site, while maintaining a minimum system pressure of 150 kPa (21.7 psi).

• The water treatment plant system’s design capacity is 21 L/s, which is the estimated 20-year maximum day demand. After the design life expires or the water demands needs surpass 21 L/s, there is space in the water treatment plant for membrane filtration expansion.

• The elevated storage reservoir has the storage capacity of 1,616,775 litres. The volume was determined using the minimum fire flows, equalization storage, and emergency storage requirements for the estimated 40-year water demand.

• The raw (lake) water intake has a design capacity for an estimated 50-year design life or an estimated 33.21 L/s.  

 

How was the network designed (pipe sizes, route, storage, pumping) to meet current needs and future growth? 

• The water distribution system was designed using a computer based hydraulic modelling program. This program’s parameters (considerations) are inputted, distribution layout, elevations (heights), pipe diameters (sizes), as well as anticipated water demands throughout the virtual hydraulic (water movement) model. Several scenarios were assessed to ensure the most feasible and operational water distribution pipe diameter was selected.

• Scenario 1 – Existing average day demand – pipe diameters provide flow and pressure requirements.

• Scenario 2 – Existing maximum day demand – pipe diameters provide flow and pressure requirements.

• Scenario 3 – Existing maximum day demand plus fire flows at the school – pipe diameters provide flow and pressure requirements.

• Scenario 4 – Existing maximum day demand and residential fire flows – pipe diameters provide flow and pressure requirements.

• Scenario 5 – 20-year average day demand – pipe diameters provide flow and pressure requirements.

• Scenario 6 – 20-year maximum day demand – pipe diameters provide flow and pressure requirements.

• Scenario 7 – 20-year maximum day demand plus fire flows at the school – pipe diameters provide flow and pressure requirements.

• Scenario 8 – 20-year maximum day demand plus residential fire flows – pipe diameters provide flow and pressure requirements.

• Scenario 9 – 20-year peak hour demand – pipe diameters provide flow and pressure requirements.

• Scenario 10 – No demand and full elevated storage reservoir – pipe diameters were within the recommended system pressure requirements.

• The route or layout of the watermain was determined by the project team.

• The storage requirements for the elevated storage reservoir (water tower) were determined using the guidelines established by The Ministry of the Environments, Conservation and Parks.

• All system pumps were selected by using the calculated system head and the required flow rates.

 

How far will service connections be from homes?

• For Curve Lake First Nation Members that have access to the water distribution system (watermain at the road) and sign a water service agreement, should be eligible to connect to the system. In the situation where only a curb stop is installed, it will be placed within 2 meters of the edge of the road. If there is a ditch at the 2-metre offset, the curb stop will be placed behind the back slope of the ditch where level ground is located.

​

What technologies are being used for the water treatment facility, the water main lines, storage tower and in-house connections? 

• Water treatment plant technology includes;

  • Chemical Coagulation - The pre-treatment system unit will consist of a coagulant injection (chemical introduction) with two trains of flocculation (chemical separation of particles), followed by two trains of dissolved air flotation (DAF). Each train will be sized to accommodate the 21 L/s 20-year maximum day demand.

  • Membrane Filtration - Main treatment process uses membrane filtration (physical separation) technology. The membrane system is designed for a multi-train N+1 configuration consisting of two trains. Each train will consist of 32 membrane modules, for a total of 64 membrane modules. Therefore, if one train requires maintenance, the WTP will still be able to supply treated water to the reservoir at maximum day flows.

  • Granular Activated Carbon Filtration - There will be two post-filtration granular activated carbon (GAC) filters (beds of sand like particles) in the treatment process. This is a polishing filter to remove any remaining contaminants for odours and taste.

  • Ultraviolet Reactors - Two ultraviolet reactors are designed into the treatment plant process and will allow for a duty/standby operation. The ultraviolet intensity will be a minimum of 40 millijoules per square centimeter (mJ/cm2) at a minimum ultraviolet transmittance (UVT) of 80%. This is a disinfection system that removes bacteria through the use of UV light.

  • Chemical Disinfection – A 12% sodium hypochlorite solution will be used to provide the required chlorination. Secondary containment for the chemicals will be provided. All chemical feed systems will have duty and stand-by metering pumps to comply with the N+1 treatment trains requirement of the Safe Drinking Water Act.

​

How will the system manage peak demand, fire flow, or future expansion?

• All water supply system components are designed to a minimum of the 20-year demand plus fire flows.

• Peak hour flows were assessed in a hydraulic (water movement) model to ensure the peak flows were attainable and the pressure was within the recommended design criteria. The elevated storage reservoir (water tower) is sized to provide the equalization volume to buffer the peak flows.

• Residential fire flows were assessed during the watermain design. The fire flows are designed in the volume of the elevated storage reservoir.

• There is an area designed into the footprint of the water treatment plant that allows for expansion.

​

Do I have to disconnect my well if I am choosing to be connected to the water system, and if so why? Can I keep my well in case of emergencies?

• The existing well connection must be disconnected from the main household plumbing system.

• The reason for disconnecting the well service line the main house plumbing is to eliminate the potential for cross contamination of unregulated well water in the regulated water in the distribution system.

• If the Curve Lake First Nation’s water policy allows for a communal water service line and a well water service line, the well service line must have a dedicated spout with no connections that would allow for potential cross contamination.