Monday, March 23, 2020

MANNHEIM WATER TREATMENT PLANT



This water treatment plant located in Kitchener receives water from the Grand River. After extensive treatment it is stored in the Mannheim Pumping Station Reservoir where it blends with numerous groundwater well sources (up to 13 wells) including the village of Mannheim wells as well as the Shingletown wells. Expenses for repairs and replacement equipment in 2019 assigned to this system totaled approximately $6 million. A couple of these costs are somewhat peculiar such as $100,000 for "St.Jacobs Fuel System Upgrades" and $2,100,00 for "Laurel Standpipe Interior Painting and Mixer".

The microbiological testing results are downright scary and trust me when the Region of Waterloo first advanced the idea of using Grand River water they sure didn't advertise the extent of harmful bacteria from that source. The raw water from the groundwater wells has a grand total of one detection of Coliforms with zero E.Coli which is appropriate. The raw water from the Grand River however had a maximum level of 85,000 Coliforms and 380 E.Coli present. That raw water source is horrific and I expect far worse than the numbers of E.Coli and Coliforms in the Walkerton wells during their water crisis. Keep in mind that this is raw water results however the failures in Walkerton occurred due to both human failure at multiple levels (municipal employees & Ministry of Environment) as well as due to faulty infrastructure either preventing physical access to groundwater wells by contaminated surface water or in the subsequent treatment and disinfection thereafter.

The Turbidity (murkiness) of river water varies dramatically based upon rain and surface water carrying sediment into the river. The maximum Turbidity of the river water is extremely high and high Turbidity makes disinfection more difficult as bacteria can "hide" from disinfection due to the foreign particles in the water. That said the Region clearly have good filtering of the raw water as post filter the Turbidity levels drop dramatically. As long as both equipment and operators do not fail, the treatment and removal of bacteria is very good.

I assume that part of the trade off in using highly contaminated (i.e. bacteria) river water is that much greater chlorination and chloramination is required to disinfect this water. That appears to be so with the specific listing of a full page of Inorganic parameters (chloramines) that exceed half the standard prescribed in the Ontario Drinking Water Standards (ODWS).

I am relieved to see that all the sampling for the 2019 Annual Report for the Mannheim Water Treatment Plant was indeed done in 2019. Sodium is a little high at 35.4 mg/l although not in comparison to some of the well sources in Cambridge or Waterloo. Nitrates on the other hand are higher than I've seen so far this spring in my examining the recently released Region of Waterloo Annual Reports. This water system to date is the only one to have Nitrates exceeding half the standard prescribed in the ODWS. Method Detection Limits (MDLs) are also very high for ten different industrial/agricultural chemicals just like the groundwater wells throughout the Region. This of course includes Glyphosate (Roundup) at a ridiculous MDL of 25 ppb.

Good news is that this report includes results for both Haloacetic Acids (HAA) and for Trihalomethanes (THMs). These are both by-rpoducts of disinfection and are not good for you. The bad news is that again likely due to the need for incredible clorination and chloramination in order to kill the bacteria in the raw water and to maintain disinfection in the treated water, these HAA and THM results are high. Due to averaging results and the joys of mathematics, HAAs are not listed as exceeding half the standard prescribed in the ODWS. In fact there is at least one HAA result which clearly does exceed half the standard. Trihalomethane results are even higher with five results exceeding half the standard and an amazing number of results hovering within a whisker of half of the standard which is 100 ppb. It certainly appears as if the 48 and 49 ppb results are the result of judicious dilution with groundwater sources prior to testing. Again likely due to averaging and mathematics THMs are also not formally listed as exceeding half the ODWS standard. In my opinion they should be.

Th O'Connell Commission which examined the failures in Walkerton, Ontario determined that our drinking water must be examined closely from source to distribution system. There must be multiple barriers to contamination getting into our water at every location including the source water. Simple reliance upon a good treatment system always maintained by certified professionals is not adequate. This principle is being violated by the Region of Waterloo and most likely by many other jurisdictions in Ontario. Any guess when and where the next water crisis will strike?

2 comments:

  1. It bears repeating that all the criteria/standards are based upon the inaccurate and ridiculous assumption that the currently being examined contaminant (i.e. chemical, bacteria etc.) is the only one in the water being tested. Therefore there is no standard for drinking water which has multiple low level contaminants in it which is the norm. Whether high sodium, intermediate Nitrates, low level solvents, low HAAs and low to medium THMs there is no known or calculated total contamination criteria or standard.

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  2. Thank you for the insights you shared.

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