Thunder Bay – Relationship Between Between Copper, Sodium Hydroxide Well Known

Chemistry professor says relationship between copper, sodium hydroxide well known

The city introduced sodium hydroxide into the municipal water supply in 2018 to reduce the amount of lead leaching into the drinking water in homes with lead pipes. The practice was discontinued in 2020 after the city received a number of complaints about pinhole leaks.

“The reaction, I think it’s a well known fact that sodium hydroxide is a corrosive material. If you put sodium hydroxide into contact with metal, it will get corroded,” said Nelson Belzile, a chemistry professor at Laurentian University.

“It’s a very alkaline, a very high pH material in solution.”

Belzile said he understands the rationale for using the chemical—it creates a coating on the inside of lead pipes that will reduce the amount of lead entering drinking water.

“This coating is created by a reaction between the sodium hydroxide and the lead material.”

He said there are other materials which could be used to achieve the same coating effect, and are not as corrosive as sodium hydroxide.

Those include phosphate, although that substance can have detrimental environmental impacts if used in high quantities, Belzile said. Silica is another substitute, which would also react with lead to create a coating layer of protection inside the pipe.

“The presence of the sodium hydroxide that is creating a problem with the copper pipe, because it is a different material, is not leading to a layer of protection, it is leading to an attack on the copper pipe, and that could create some leaks that have been observed in some locations.”

“Other cities have faced the problem, and have tested other materials. They have tested other things that are not necessarily sodium hydroxide, but other compounds that will adjust the pH,” said Belzile.

Belzile said the best way to eliminate lead in water is to replace all lead pipes, although he does understand the cost involved with pipe replacement. Another option, he said, is to use a water filter which does remove lead.

– tbnewswatch

read full article here

“The reaction, I think it’s a well known fact that sodium hydroxide is a corrosive material. If you put sodium hydroxide into contact with metal, it will get corroded,” said Nelson Belzile, a chemistry professor at Laurentian University.

“Other cities have faced the problem, and have tested other materials. They have tested other things that are not necessarily sodium hydroxide, but other compounds that will adjust the pH,” said Belzile.

Soooo, if you put sodium hydroxide into contact with metal, it WILL get corroded. OTHER cities have faced the problem, and have tested other materials.

Belzile said the best way to eliminate lead in water is to replace all lead pipes, although he does understand the cost involved with pipe replacement. Another option, he said, is to use a water filter which does remove lead.

The City of Thunder Bay is replacing much of its water and sewer infrastructure.  Residential lead pipes could be replaced at the same time. The cost of this work could be spread out over 10 or 15 years. Added to the property taxes.

What the City of Thunder Bay is not telling us is that it is not replacing all of the lead pipes on its own property.

I believe a building that has lead water pipes has a reduced assessment value…..or it should have a reduced assessment value.  Reduced assessment values would mean fewer tax dollars pouring into the city’s coffers.  THAT might be a big enough incentive for our high salaried residents of City Hall to do something. Money talks. Less money talk even louder.

Water filters remove lead.  An inline water filter works and is a cheaper solution.

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3 Responses

  1. William A Olesky
    William A Olesky at | | Reply

    But what of all the people with damaged pipes?

  2. William A Olesky
    William A Olesky at | | Reply

    From your keyboard to God’s ears…

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