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The Town of Petawawa has contracted the services of the Ontario Clean Water Agency (OCWA) to maintain and operate both the Wastewater Facilities as well the Water Treatment Facilities. OCWA may be reached at: P.O. Box 128, 560 Petawawa's water treatment facility was upgraded to a state of the art, fully automated plant in 1993. Thanks to the forward-thinking Council of the day, residents of the community have the benefit of utilizing water that complies with and surpasses the highest drinking water standards in the industry. The process consists of flocculation, sedimentation, clarification, and filtration, and finally, chlorination. All of these modern day processes are in place to ensure the highest quality drinking water. Located on the South shore of the Ottawa River and surrounded by CFB Petawawa, the facility is rated at 21,500 cubic metres/day and at present day, is running at less than half of its rated capacity. All aspects of the treatment process are continually monitored and alarmed, 24 hours per day, seven days per week. Routine samples are collected and analyzed for microbiological, chemical, volatile organics, inorganics and pesticides on a daily, weekly, monthly and yearly basis. << Back to top Background HistoryIn 1963, the Ontario Resources Commission entered into an agreement with DND for the Base Water Pumping Station to supply 2,050 m3/d to the Village of Petawawa. In 1968 a Water Treatment Plant was constructed by DND, a class 3 direct filtration plant. 1976 the Ministry of the Environment requests the water quota to the Village of Petawawa be increased to 3,180 m3/d of its 14,500m3/d capacity. This request initiated several studies into the need for system expansion. 1989 Department of National Defense announces an expansion to CFB Petawawa and their intention to recall the water quota allocated to the Village of Petawawa. The Village of Petawawa was then given the option to own and operate the plant and pay for the upgrading needed to provide the additional capacity for their use. October 30,1992, the contract was awarded for the expansion of the Water Treatment Plant. The present plant has a rated capacity of 21,500 m3/d and is located on Lot 26, Lake Range, Town of Petawawa on the south shore of The Ottawa River surrounded by CFB Petawawa. << Back to top Quality Control and Compliance with Provincial RegulationsThis plant provides multiple barriers against bacteriological contamination. Bacteriological testing is carried out on raw water, treated water and distribution samples on a regular frequency. On-line analyses for chlorine residuals and turbidity ensure continuous monitoring of water leaving the plant Chlorine levels in the distribution system are also checked on a regular basis. More specialized testing occurs monthly and quarterly and includes pesticides, heavy metals, disinfection by-products, volatiles and organics. << Back to top Plant Description and Current Treatment ProcessesThe plant's water treatment process consists of the following:
Raw Water SourceThe source of water treated by the Petawawa water plant is the Ottawa River at a widening in the river called Allumette Lake. The 760 mm diameter intake pipe extends 490m into the river at approximately 6m +1- under the surface and 1.5 m off of the bottom of the river. This raw water intake pipe has a capacity of 21,500 cubic meters per day gravity feed to the raw water well, and is supported at the end with a concrete and timber crib. ScreeningA vertical stainless steel coarse screen in the Raw water well of the low lift area of the building removes any large debris such as weeds, fish, etc. Low Lift PumpsThere are three low lift pumps that lift the water from river level via a 400 mm header to the flash mix tanks. From there the water can gravity flow through the various plant processes. Chemical Feed SystemPre-hydroxylated Aluminum sulphate (PAS-8) and a polyelectrolyte are used to create a 'floc'. The floc captures suspended particles (colour, dirt, etc.) which may be found in the raw water. This 'capture' process aids in their removal. The pH adjustment is achieved by the addition of Sodium Bicarbonate, pre and post Flash Mix TankThis 50 m3 tank provides the necessary mixing or blending of the raw water and the added coagulants. Contact TanksFollowing the mixing and coagulation in flash mix tank it is necessary to gently agitate the chemically treated water inthe flocculation tanks to promote particle collision and formation of larger floc. ClarificationThe floc created by the coagulation is settled in the clarifiers. The rectangular clarifiers rely on slow longitudinal flow to allow enough time for the particles to settle. These particles are collected by a tracvac sludge vacuum system. This system transfers the settled sludge to two wastewater tanks for water separation and disposal. FiltersThe plant is equipped with three dual media (sand/antharcite) filters. The filters remove particles (suspended solids) that are present in the raw water, as well as compounds that cause taste and odours. Filters are washed regularly on a backwash cycle to prevent any buildup on the filters. Pre ChlorinationPre-chlorination of chlorine gas and water is added to the clarifier effluent channel to assist in the removal of color, help control tastes and odour, and / or to oxidize organic and inorganic elements. Post ChlorinationChlorine gas and water is which is added to the water as it enters the clearwell. Sufficient amounts of chlorine is used to disinfect the treated water and to provide a chlorine residual which remains in the distribution system. This ensures water quality protection to the customers' location. The clearwell provides water storage for the high lift pumps and has 1650 cubic meters of total storage capacity. High Lift PumpsThere are three high lift pumps that discharge the treated water into a 500 mm header that connects into a 400 mm line and a 500 mm line leaving the plant and connecting into the distribution system. Standby PowerA 325 kW diesel generator is located at the water treatment plant to provide power to essential equipment to ensure a continuous supply of water during power failures. Elevated TankThere are four functional towers in the Town of Petawawa, as of August 2010. A 2,250 m3 tower located on DND south townsite, and a 4,500 m3 tower located on Woodland Crescent. The third tower is located on Tower Road, having a capacity of 2,250 m3. A fourth tower has been commissioned on the property of CFB Petawawa that has a capacity of 3,785 m3, totaling 12,785 m3 or approximately 1,000,000 gallons of water storage. Once the new tower is fully operational and maintained by OCWA staff, the south townsite elevated tank will eventually be decommissioned. Distribution SystemApproximately 11,475 people are supplied with water from the Petawawa Water Treatment Plant. << Back to top Petawawa Water Rates
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