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Water Processes & Treatment

The Process

Water Treatment and Hydro Generation

Filter Sock Chamber

Filter Sock Chamber

Surface water undergoes coarse filtration in the filter sock chamber, which houses six perforated PVC  pipes covered with mesh filter media (socks).  Each pipe is approximately 12” in diameter and 8’ long. Coarse filtration removes large debris, such as leaves, sticks, pine needles, frogs, etc. These filter socks can become clogged, especially during the freshet, and require constant monitoring and cleaning. Coarse filtration is not technically considered part of the water treatment process because fine materials and micro-organisms are not removed.

Before the water from the sock chamber moves to the water treatment plant it is sent to the Micro Hydro generation station. When the coarse-filtered water is sent to the generation station, the high pressure in the water main turns the micro hydro generator, which creates hydroelectricity.  This electricity is sold to BC Hydro and is fed back into their power grid.  The Village is licensed to produce 50 kilowatts of power.  From the generating station, the coarse-filtered water is sent on to the water treatment plant.

At the water treatment plant, the treatment process for surface water consists of membrane microfiltration, UV light and chlorine injection.  This is a very technical operation, which is classified as a Level II Water Treatment and Water Distribution system. Once treated, the water is stored in the Village’s million-gallon reservoir.

Upper Brouse Road Water Treatment Plant

Upper Brouse Road Water Treatment Plant

The million-gallon reservoir has an interior liner over its bottom and sides, and a polyvinyl chloride cover over the top to keep out debris and wildlife.  Towers and weights installed around the perimeter of the reservoir allow the cover to move with the water level. The reservoir is 14’ deep.

The Village also has a 200,000 gallon reservoir, which stores treated water for the lower grid.

Surface Water Sources

Surface water sources consist of Halfway Creek, Upper Brouse Creek and Lower Brouse Creek.  The piping network consists of 3.5 kilometers of pipe to the Upper Brouse intake and an additional 3.5 kilometers to the Halfway intake.

Groundwater Sources

Water Reservoir

Water Reservoir

The Village currently has two established production wells: Well#1 and Well#2.  Both wells are located adjacent to the sports complex and are drawn from the same aquifer. A small amount of chlorine is injected into the discharge line, in order to maintain a residual in the distribution system.

Well#1 (8”) consistently produces 25 L/s (330 IGPM), taking the demand off the surface water system in the summer, and it operates up to 24 hours/day. This flow, combined with the 70 L/s from the surface system (during peak daily demand), provides 95 L/s summer flows. This flow is adequate for the needs of the village at the present time. A single well, however, leaves the village at risk in the event of mechanical breakdown.

Well#2 (12”) was drilled for redundancy and to accommodate village growth, and it has been tested up to 63 L/s (800 IGPM).  This well was commissioned with the same pump and motor as Well #1 and, therefore has the same capacity.

Monitoring & Maintenance

Water System Diagram

Water System Diagram

In addition to the daily facility checks that are conducted by Utility Operators, the Village has the benefit of a Supervisory Control and Data Acquisition (SCADA) system.  This system allows the various facilities to communicate remotely through wireless modem radios and sensing equipment, enabling Public Works operators to log onto the system to view and/or manipulate reservoir levels, well pump operations, turbidity and chlorine levels, and system flows. The system also logs this data into an archive for reporting purposes. The system is a very valuable component of the water system, allowing operators to manage the water supplies and view problems on an on-going basis.

Water Sampling & Testing

With the implementation of the new water treatment plant (2014), the following Water Quality Monitoring Program was instituted: 

Water Quality Monitoring Program

Schedule

Tasks

WEEKLY

  • Microbiological testing at various test sites throughout the distribution system
  • Raw water microbiological testing at all pre-chlorination source sites

MONTHLY

  • THM testing on a rotational basis throughout the distribution system;
  • Microbiological results reporting;
  • Daily water consumption data;
  • Turbidity monitoring data;
  • UV data
  • Chlorine monitoring data
  • UV sensor reference checks
  • Reporting of source, treatment & distribution system events;
  • Reporting of customer complaints & responses;
  • Outlining major operational activities;
  • Recording of calibration of the chlorine residual analyzer

QUARTERLY

  • Holoacetic acids testing and reporting

SEMI-ANNUALLY

(until baseline has been established – then annually)

  • Baseline analysis for potential contaminants of groundwater, including: hydrocarbons (benzene, toluene, ethylbenzene & xylene, light and heavy extractable petroleum hydrocarbons -including polyaromatic hydrocarbons, volatile organic compounds; herbicides and pesticides; metals, nitrates; nitrites and phosphorus; and/or microbiological parameters (coliforms, E. coli);
  • Testing of any specific contaminants of concern

ANNUALLY

  • Full comprehensive raw water analysis of each water source
  • Comprehensive Annual Report

Routine Maintenance

Daily

Visual checks are conducted of the various facilities to ensure that the equipment is functioning properly and no problems are evident.  Filter sock cleaning is done, as required.  The system is also monitored 24/7 by the SCADA system, which can be accessed remotely by operators.  The system is monitored for:  flow rate, total flow, free chlorine, chlorine pump settings, pH, temperature, well levels, and turbidity.

Weekly

Every Tuesday, the Village conducts facility inspections and bacteriological water sample testing is done at various end-line locations throughout the municipality. 

Monthly

Flow rate information is compiled for the million-gallon reservoir and the wells.  Monthly samples are taken to monitor Trihalomethane levels.  Sample results are reported to Interior Health.

Annually

  • Waterlines are flushed in the spring and fall. 
  • This removes debris and stale water that may have accumulated in the piping network.
  • Fire hydrants are also flushed and inspected.   Any repairs necessary are made and two new hydrants are installed each year.
  • A valve exercising program is conducted each year to ensure that valves remain in good working order.  
  • The Halfway water intake is back-flushed annually to remove settled debris and improve flow. 
  • As part of the Village’s Cross Connection Control Program, backflow preventer devices are inspected and tested to prevent any cross contamination of the potable water system.  
  • An annual report is submitted to the Interior Health Authority summarizing the conditions of the Operating Permit.

On-going

Data is constantly monitored to assist with identifying leaks in the system.  Repairs are made immediately.
The million-gallon reservoir cover is pumped off regularly, to remove any precipitation and debris.

A few facts . . .

  • The Village water system is comprised of 756 residential connections, 103 commercial services and 27 institutional/industrial services. 
  • Currently, the distribution system runs approximately 26.7 kilometers and uses both surface source water and ground well water.