Decew Falls Water Treatment Plant - 2015 Annual Water Quality Report

The Annual Water Quality Report summarizes the quality of drinking water from the Decew Falls Water Treatment Plant from January 1 to December 31, 2015.

The Decew Falls Water Treatment Plant Summary Report is available for inspection.

Description of Drinking Water System

A conventional surface water treatment plant incorporates the following steps in its purification process:

  • Zebra mussel control
  • Travelling screens
  • Coagulation
  • Flocculation
  • Sedimentation
  • Filtration
  • Disinfection

This process consists of three separate treatment trains; referred to as Plant 1, Plant 2, and Plant 3, with a combined rated capacity of 227,300 m3/day. Primary disinfection is achieved utilizing sodium hypochlorite with ultraviolet light as enhancement. The DeCew Falls Water Treatment Plant supplies drinking water to the City of St. Catharines, City of Thorold, Town of Niagara-on-the-Lake, and sections of the Town of Lincoln, and is located at 2700 DeCew Rd.

The water treatment chemicals used over this reporting period are:

  • Sodium Hypochlorite
  • Aluminum Sulphate

Monetary Expenses Incurred

To ensure safe and efficient operations, the following major repairs or upgrade projects took place:

  • Water trunk main replacement project and various water main repairs: $59,000
  • Decew Falls Water Treatment Plant - Plant 1 structural and process upgrades (completed): $8,331,000
  • Security system upgrades: $164,000
  • Sodium Hypochlorite chemical feed system replacement: $150,000
  • Installation of de-chlorination metering pumps and analyzers: $787,000

Water Quality Test Results

Microbiological

Total Coliform and E.coli bacteria tests are performed on raw, treated and distributed drinking water.

Test Number of Samples Range of E.Coli or Fecal Results (minimim number)-(maximum number) Range of Total Coliform Results (minimim number)-(maximum number) Number of HPC* Samples Range of HPC Results (minimim number)-(maximum number)
Raw 52 0-40 0-4400 (OG) Not applicable Not applicable
Treated 158 0-0 0-1 156 0-11
Distribution 312 0-0 0-0 312 0-51

OG=Over Grown

*HPC (heterotrophic plate count) bacteria indicate biological growth. They are not harmful to humans and do not represent poor drinking water quality.

Operational

Operational tests are done by treatment plant operators to evaluate process conditions and to make adjustments to the process.

Test Number of Samples Range of Results (minimim number)-(maximum number)
Turbidity 8760 0.007-0.294 NTU*
Chlorine 8760 0.59-2.00 mg/L
Fluoride Not applicable  

*NTU (nephelometric turbidity units) is a unit that measures the lack of water clarity.

An analyzer continuously monitors the water treatment process and records results on a predetermined frequency. Continuous monitors use 8760 as the number of samples.

Inorganics

Inorganic substances include heavy metals and dissolved minerals that may be present in treated drinking water. The following is a summary of inorganic parameters tested or the most recent sample results.

Parameter Sample Date Result Value Unit of Measure Exceedance
Antimony Nov. 4, 2015 <0.5 μg/L 0
Arsenic Nov. 4, 2015 <1.0 μg/L 0
Barium Nov. 4, 2015 21.4 μg/L 0
Boron Nov. 4, 2015 19.7 μg/L 0
Cadmium Nov. 4, 2015 <0.1 μg/L 0
Chromium Nov. 4, 2015 <1.0 μg/L 0
Mercury Nov. 4, 2015 <0. 1 μg/L 0
Selenium Nov. 4, 2015 <1.0 μg/L 0
Sodium Dec. 2, 2015 10.9 mg/L 0
Uranium Nov. 4, 2015 <1.0 μg/L 0
Fluoride Dec. 2, 2015 <0.16 mg/L 0
Nitrite Dec. 2, 2015 <0.05 mg/L 0
Nitrate Dec. 2, 2015 0.35 mg/L 0

Organics

Trace organic test parameters include: volatile organic substances, pesticides, solvents, dioxins, PCB's, and disinfection by-products. The following is a summary of organic parameters tested or the most recent sample results.

Parameter Sample Date Result Value Unit of Measure Exceedance
Alachlor Nov 4, 2015 <0.5 μg/L 0
Aldicarb Nov 4, 2015 <0.6 μg/L 0
Aldrin + Dieldrin Nov 4, 2015 <0.004 μg/L 0
Atrazine + N-dealkylated metobolites Nov 4, 2015 <0.9 μg/L 0
Azinphos-methyl Nov 4, 2015 <0.4 μg/L 0
Bendiocarb Nov 4, 2015 <1.0 μg/L 0
Benzene Nov 4, 2015 <0.2 μg/L 0
Benzo(a)pyrene Nov 4, 2015 <0.005 μg/L 0
Bromoxynil Nov 4, 2015 <0.09 μg/L 0
Carbaryl Nov 4, 2015 <1.0 μg/L 0
Carbofuran Nov 4, 2015 <1.0 μg/L 0
Carbon Tetrachloride Nov 4, 2015 <0.2 μg/L 0
Chlordane (Total) Nov 4, 2015 <0.004 μg/L 0
Chlorpyrifos Nov 4, 2015 <0.4 μg/L 0
Cyanazine Nov 4, 2015 <0.4 μg/L 0
Diazinon Nov 4, 2015 <0.4 μg/L 0
Dicamba Nov 4, 2015 <0.08 μg/L 0
1,2-Dichlorobenzene Nov 4, 2015 <0.2 μg/L 0
1,4-Dichlorobenzene Nov 4, 2015 <0.2 μg/L 0
Dichlorodiphenyltrichloroethane (DDT) + metabolites Nov 4, 2015 <0.005 μg/L 0
1,2-Dichloroethane Nov 4, 2015 <0.2 μg/L 0
1,1-Dichloroethylene (vinylidene chloride) Nov 4, 2015 <0.2 μg/L 0
Dichloromethane Nov 4, 2015 <1.0 μg/L 0
2-4 Dichlorophenol Nov 4, 2015 <0.2 μg/L 0
2,4-Dichlorophenoxy acetic acid (2,4-D) Nov 4, 2015 <0.08 μg/L 0
Diclofop-methyl Nov 4, 2015 <0.08 μg/L 0
Dimethoate Nov 4, 2015 <0.4 μg/L 0
Dinoseb Nov 4, 2015 <0.07 μg/L 0
Diquat Nov 4, 2015 <7.0 μg/L 0
Diuron Nov 4, 2015 <0.6 μg/L 0
Glyphosate Nov 4, 2015 <20.0 μg/L 0
Heptachlor + Heptachlor Epoxide Nov 4, 2015 <0.004 μg/L 0
Lindane (Total) Nov 4, 2015 <0.0005 μg/L 0
Malathion Nov 4, 2015 <0.4 μg/L 0
Methoxychlor Nov 4, 2015 <0.001 μg/L 0
Metolachlor Nov 4, 2015 <0.2 μg/L 0
Metribuzin Nov 4, 2015 <0.2 μg/L 0
Monochlorobenzene Nov 4, 2015 <0.2 μg/L 0
Paraquat Nov 4, 2015 <1.0 μg/L 0
Parathion Nov 4, 2015 <0.2 μg/L 0
Pentachlorophenol Nov 4, 2015 <0.5 μg/L 0
Phorate Nov 4, 2015 <0.2 μg/L 0
Picloram Nov 4, 2015 <0.08 μg/L 0
Polychlorinated Biphenyls(PCB) Nov 4, 2015 <0.08 μg/L 0
Prometryne Nov 4, 2015 <0.1 μg/L 0
Simazine Nov 4, 2015 <0.4 μg/L 0
THM Annual Average 5.92 μg/L 0
Temephos Nov 4, 2015 <20 μg/L 0
Terbufos Nov 4, 2015 <0.1 μg/L 0
Tetrachloroethylene Nov 4, 2015 <0.2 μg/L 0
2,3,4,6-Tetrachlorophenol Nov 4, 2015 <0.5 μg/L 0
Triallate Nov 4, 2015 <0.2 μg/L 0
Trichloroethylene Nov 4, 2015 <0.2 μg/L 0
2,4,6-Trichlorophenol Nov 4, 2015 <0.5 μg/L 0
2,4,5-Trichlorophenoxy acetic acid (2,4,5-T) Nov 4, 2015 <0.09 μg/L 0
Trifluralin Nov 4, 2015 <0.2 μg/L 0
Vinyl Chloride Nov 4, 2015 <0.2 μg/L 0

Adverse Water Quality Incidents

Drinking water regulations identify "Indicators of Adverse Water Quality". Health officials and the Ministry must be immediately notified if indicators are found. These refer to any test result from treated or distributed drinking water that does not meet a provincial water quality standard or a situation where disinfection of the water may be compromised. The following notices were submitted in accordance with subsection 18(1) of the Safe Drinking-Water Act or section 16-4 of Schedule 16 of O.Reg.170/03 and reported to the Spills Action Centre.

Incident Date Parameter Result Unit of Measure Corrective Action Date of Resolution
Feb. 13, 2015 Filter effluent turbidity Not applicable NTU Restored flow Feb. 13, 2015
Feb. 19, 2015 Total Coliform 1 cfu/100mL Resample(s) Feb. 19, 2015

cfu=colony forming units

Lead Testing

The following is a summary of lead testing.

Location Type Number of Samples Range of Lead Results Unit of Measure Exceedance
Plumbing 5 0 - < 0.1 μg/L 0
Distribution 5 0 - < 0.1 μg/L 0

Page Feedback Did you find what you were looking for today?