Decew Falls Water Treatment Plant - 2018 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, 2018.

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

The plant 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:

  • Plant 3 upgrade design - $150,000
  • SCADA improvements - $83,000
  • Virgil Elevated Tank rehabilitation - $331,000
  • Pressure reducing valve and chamber Niagara-on-the-Lake - $91,000
  • Martindale Road Watermain - $640,000

Notices Submitted

Incident Date Parameter Result Unit of Measure Corrective Action Corrective Action Date
September 6, 2018 Total Coliforms 1 CFU/100mL Resample. Resample results met regulatory requirements. September 10, 2018

Water Quality Test Results

Starting in 2018, reported units of measure have been updated to match the units of measure included within Ontario Regulation 169/03 - Ontario Drinking Water Quality Standards.

Reported results that are shown with a less than symbol (<) before the value indicates that the sample result is below the lowest possible detection limit for the parameter.

Microbiological

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

Microbiological testing done under the Schedule 10, 11 or 12 of Regulation 170/03, during this reporting period.

Test Number of Samples Range of E.Coli or Fecal Results (minimum number)-(maximum number) Range of Total Coliform Results (minimum number)-(maximum number) Number of HPC* Samples Range of HPC Results (minimum number)-(maximum number)
Raw 52 0-10 0-11,000 Not applicable Not applicable
Treated 156 0-0 0-1 156 0-16
Distribution 312 0-0 0-0 312 0-127

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

Operational

Operational testing done under Schedule 7, 8 or 9 of Regulation 170/03 during the period covered by this Annual Report.

Test Number of Samples Range of Results (minimum number)-(maximum number)
Turbidity 8760 0.010-0.264 NTU*
Chlorine 8760 0.64-1.80 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.

Summary of additional testing and sampling carried out in accordance with the requirement of an approval, order or other legal instrument.

Date of legal instrument issued Parameter Date Sampled Result Unit of Measure
Municipal Drinking Water Licence: January 12, 2017 Total Suspended Solids (to environment) Weekly Annual Average 11.0 mg/L
Municipal Drinking Water Licence: January 12, 2017 Free Chlorine Residual (to environment) Weekly 0.00 mg/L

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. 14, 2018 <0.0005 mg/L 0
Arsenic Nov. 14, 2018 <0.001 mg/L 0
Barium Nov. 14, 2018 0.017 mg/L 0
Boron Nov. 14, 2018 0.014 mg/L 0
Cadmium Nov. 14, 2018 <0.0001 mg/L 0
Chromium Nov. 14, 2018 0.001 mg/L 0
Lead* - - - -
Mercury Nov. 14, 2018 <0.0001 mg/L 0
Selenium Nov. 14, 2018 <0.0005 mg/L 0
Sodium Dec. 5, 2018 8.0 mg/L 0
Uranium Nov. 14, 2018 <0.001 mg/L 0
Fluoride Dec. 5, 2018 0.060 mg/L 0
Nitrite Dec. 5, 2018 <0.008 mg/L 0
Nitrate Dec. 5, 2018 0.21 mg/L 0

*Only for drinking water systems testing under Schedule 15.2; this includes large municipal non-residential systems, small municipal non-residential systems, non-municipal seasonal residential systems, large non-municipal non-residential systems, and small non-municipal non-residential systems.

Summary of lead testing under Schedule 15.1 during this reporting period
(applicable to the following drinking water systems; large municipal residential systems, small municipal residential systems, and non-municipal year-round residential systems)

Location Type Number of Samples Range of Lead Results (min to max) Unit of Measure Exceedance
Plumbing 5 0 - <0.0001 mg/L 0
Distribution 5 0 - <0.0001 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. 14, 2018 <0.000247 mg/L 0
Atrazine + N-dealkylated metobolites Nov. 14, 2018 <0.0005 mg/L 0
Azinphos-methyl Nov. 14, 2018 <0.000185 mg/L 0
Benzene Nov. 14, 2018 <0.0001 mg/L 0
Benzo(a)pyrene Nov. 14, 2018 <0.000005 mg/L 0
Bromoxynil Nov. 14, 2018 <0.0000896 mg/L 0
Carbaryl Nov. 14, 2018 <0.001 mg/L 0
Carbofuran Nov. 14, 2018 <0.001 mg/L 0
Carbon Tetrachloride Nov. 14, 2018 <0.0002 mg/L 0
Chlorpyrifos Nov. 14, 2018 <0.000185 mg/L 0
Diazinon Nov. 14, 2018 <0.000185 mg/L 0
Dicamba Nov. 14, 2018 <0.0000784 mg/L 0
1,2-Dichlorobenzene Nov. 14, 2018 <0.0002 mg/L 0
1,4-Dichlorobenzene Nov. 14, 2018 <0.0003 mg/L 0
1,2-Dichloroethane Nov. 14, 2018 <0.0002 mg/L 0
1,1-Dichloroethylene (vinylidene chloride) Nov. 14, 2018 <0.0003 mg/L 0
Dichloromethane Nov. 14, 2018 <0.0002 mg/L 0
2-4 Dichlorophenol Nov. 14, 2018 <0.000336 mg/L 0
2,4-Dichlorophenoxy acetic acid (2,4-D) Nov. 14, 2018 <0.001 mg/L 0
Diclofop-methyl Nov. 14, 2018 <0.000112 mg/L 0
Dimethoate Nov. 14, 2018 <0.000185 mg/L 0
Diquat Nov. 14, 2018 <0.002 mg/L 0
Diuron Nov. 14, 2018 <0.005 mg/L 0
Glyphosate Nov. 14, 2018 <0.02 mg/L 0
HAA Running annual average 0.022*    
Malathion Nov. 14, 2018 <0.000185 mg/L 0
2-Methyl-4-chlorophenoxyacetic acid (MPCA) Nov. 14, 2018 <0.0056 mg/L 0
Metolachlor Nov. 14, 2018 <0.000124 mg/L 0
Metribuzin Nov. 14, 2018 <0.000124 mg/L 0
Monochlorobenzene Nov. 14, 2018 <0.0005 mg/L 0
Paraquat Nov. 14, 2018 <0.005 mg/L 0
Pentachlorophenol Nov. 14, 2018 <0.0003 mg/L 0
Phorate Nov. 14, 2018 <0.000124 mg/L 0
Picloram Nov. 14, 2018 <0.0000784 mg/L 0
Polychlorinated Biphenyls(PCB) Nov. 14, 2018 <0.00006 mg/L 0
Prometryne Nov. 14, 2018 <0.0000618 mg/L 0
Simazine Nov. 14, 2018 <0.000185 mg/L 0
THM Running annual average 0.050*    
Terbufos Nov. 14, 2018 <0.000124 mg/L 0
Tetrachloroethylene Nov. 14, 2018 <0.0003 mg/L 0
2,3,4,6-Tetrachlorophenol Nov. 14, 2018 <0.0003 mg/L 0
Triallate Nov. 14, 2018 <0.000124 mg/L 0
Trichloroethylene Nov. 14, 2018 <0.0002 mg/L 0
2,4,6-Trichlorophenol Nov. 14, 2018 <0.0002 mg/L 0
Trifluralin Nov. 14, 2018 <0.000124 mg/L 0
Vinyl Chloride Nov. 14, 2018 0.0001 mg/L 0

*The maximum distribution sample point running annual average (calculated in the last quarter of 2018) was used for this report.

Any Inorganic or Organic parameter(s) that exceeded half the standard prescribed in Schedule 2 of Ontario Drinking Water Quality Standards.

Parameter Result Value Unit of Measure Date of Sample
THM 0.050 mg/L Running annual average
Page Feedback Did you find what you were looking for today?