"Chlorine Burn": Chloramine vs chlorine in water supply?

[goody222]

Apparently chloramine is used as our tap water disinfectant. Our water doesn't have much of a smell at all to it. Our city is doing maintenance that requires switching to free chlorine to perform a Chlorine Burn and said that the water will have a strong chlorine odor (see artlicle below). They did this 6 years ago and the water sure did have a very strong odor - especially when taking a shower! But shouldn't the smell issue be reversed? Shouldn't free chlorine have no smell and the normal chloramine be the one with the strong odor? Thanks!

 

[Bperry]

Apparently chloramine is used as our tap water disinfectant. Our water doesn't have much of a smell at all to it. Our city is doing maintenance that requires switching to free chlorine to perform a Chlorine Burn and said that the water will have a strong chlorine odor (see artlicle below). They did this 6 years ago and the water sure did have a very strong odor - especially when taking a shower! But shouldn't the smell issue be reversed? Shouldn't free chlorine have no smell and the normal chloramine be the one with the strong odor? Thanks!


View attachment 475124

Sounds like they plan to do a SLAM. Still not sure I’d drink the water if filtered is available.

 

[setsailsoon]

My wife and I lived on a sailboat for about 6 years. We made all our own water from sea water with a high pressure RO unit. It was fantastic water that had similar analysis to the higher quality bottled waters. When we decided to swallow the anchor we couldn't stand the taste of any city water. Chloramines and chlorine both taste terrible to us. So we installed under counter RO units. That's all we drink. When we rented a condo for one year we used a zero filter which results in similar quality to RO.

Chris

 

[JoyfulNoise]

The smell from CCs comes mainly from dichloramine and nitrogen trichloride, not monochloramine. Monochloramine is what is primarily used in water delivery systems as it is an effective enough disinfectant, a lot less powerful oxidizer than chlorine, and it has a long lasting residual in water. Chlorine is not a very good long haul disinfectant because it’s too reactive. The smell you get from the municipal water supplier doing a disinfecting chlorine run is typically from stuff on your end of the plumbing and anything the chlorine reacts with in the sink. Chlorine that is aerosolized gets into your nose and generates chloramines when it contacts the mucous membrane.

 

[setsailsoon]

The smell from CCs comes mainly from dichloramine and nitrogen trichloride, not monochloramine. Monochloramine is what is primarily used in water delivery systems as it is an effective enough disinfectant, a lot less powerful oxidizer than chlorine, and it has a long lasting residual in water. Chlorine is not a very good long haul disinfectant because it’s too reactive. The smell you get from the municipal water supplier doing a disinfecting chlorine run is typically from stuff on your end of the plumbing and anything the chlorine reacts with in the sink. Chlorine that is aerosolized gets into your nose and generates chloramines when it contacts the mucous membrane.

eeeewwww! No wonder we can't stand it!

 

[Mdragger88]

The smell from CCs comes mainly from dichloramine and nitrogen trichloride, not monochloramine. Monochloramine is what is primarily used in water delivery systems as it is an effective enough disinfectant, a lot less powerful oxidizer than chlorine, and it has a long lasting residual in water. Chlorine is not a very good long haul disinfectant because it’s too reactive. The smell you get from the municipal water supplier doing a disinfecting chlorine run is typically from stuff on your end of the plumbing and anything the chlorine reacts with in the sink. Chlorine that is aerosolized gets into your nose and generates chloramines when it contacts the mucous membrane.

This explains A LOT! Thank you!
We live basically Nextdoor to the water tower for our little community & when we first moved in 11 years ago all our bathrooms smelled like an indoor swimming pool on regular occasion. I called about it & the woman told me something about when they drain & refill the water tower they add more chlorine which didn’t make sense to me either, I assumed doing so would have the opposite effect like @goody222 .

 

[JoyfulNoise]

Chlorine is typically used in the early stages of water treatment after sedimentation, flocculation and primary filtration. You want to get rid of as much natural organic matter as possible and even do some early ozonation (if available) to avoid having the chlorine generate harmful oxidation byproducts. After fine filtration and polishing, water plants will typically inject ammonia and chlorine gas into the delivery stream to create monochloramine in-situ. What usually exits the facility is water with a low amount of FC (less than 0.8ppm) and CC’s usually greater than 1.0ppm. If you ever measure a tap water FC above 1.5ppm, then there’s likely something going on that the water treatment plant had to fix. They should warn people about that in most instances because the chlorine odor will be significant and easily detectable above 1ppm.

 

[colonelkirby]

Chlorine is typically used in the early stages of water treatment after sedimentation, flocculation and primary filtration. You want to get rid of as much natural organic matter as possible and even do some early ozonation (if available) to avoid having the chlorine generate harmful oxidation byproducts. After fine filtration and polishing, water plants will typically inject ammonia and chlorine gas into the delivery stream to create monochloramine in-situ. What usually exits the facility is water with a low amount of FC (less than 0.8ppm) and CC’s usually greater than 1.0ppm. If you ever measure a tap water FC above 1.5ppm, then there’s likely something going on that the water treatment plant had to fix. They should warn people about that in most instances because the chlorine odor will be significant and easily detectable above 1ppm.

Interesting. Thanks for the explanation. In Plano, TX every March, the water treatment folks stop adding ammonia to the mix. They warn us the level of chlorine is the same as always, but without the ammonia the chlorine odor/taste is more prevalent. It's bad for sure. Not sure they have ever explained why in detail other than its planned.

 

[JoyfulNoise]

Interesting. Thanks for the explanation. In Plano, TX every March, the water treatment folks stop adding ammonia to the mix. They warn us the level of chlorine is the same as always, but without the ammonia the chlorine odor/taste is more prevalent. It's bad for sure. Not sure they have ever explained why in detail other than its planned.

It’s precautionary most likely. They want to disinfect the lines to avoid any contamination issues. Biofouling is not only a human health hazard but it can also wreck very expensive equipment. And the EPA will drop the hammer with huge fines on any water district that messes up … unless you derail a train full toxic chemicals that burn for days on end, then they’re like “whatevs … no biggie! Nothing to see here …”

 

[goody222]

Wow, I'm learning so much today. Thanks everyone!