[MegaKeeperMan]

Hey chemists!

I'm working on a chemistry report, I've searched everywhere but I can't find an answer to what the typical levels of alkalinity is in lakes and streams.

I tested a stream to have 50ppm alkalinity (1.0mEq/L) and a lake to have 30ppm (0.6mEq/L). Are those normal values? What are healthy values for these bodies of water?

Thanks in advance, Megs

[Archer]

The regulations for these waters will differ from one country to the next.

Is it recreational water, i.e. swimming etc.

Are you in the North America, South America, Europe, India, Africa?

[Archer]

This may be of some help

http://water.epa.gov/type/rsl/monitoring/vms510.cfm

[MegaKeeperMan]

The regulations for these waters will differ from one country to the next.

Is it recreational water, i.e. swimming etc.

Are you in the North America, South America, Europe, India, Africa?

I live in Sweden. The lake sample was taken from a creek called "Bråviken" in the Baltic Sea (Europe,  https://www.google.se/maps/place/Br%C3%A5viken/@58.6095006,16.5893684,10z/data=!3m1!4b1!4m2!3m1!1s0x4659283e54d18a11:0x8b0253157ad3a594). Let me know if you need any more information.

[MegaKeeperMan]

This may be of some help

http://water.epa.gov/type/rsl/monitoring/vms510.cfm

Thanks for the link, mate. Read through it but it unfortunately doesn't answer my questiom.

[Archer]

Thanks for the link, mate. Read through it but it unfortunately doesn't answer my questiom.

I have not really understood the question.

I am a Public Analyst and one of my areas is water analysis. Unfortunately this scope does not include lakes.

I think what would help me would be if you explained to me your definition of "healthy" on reference to any parameter that you could be measuring.

Obviously in the case of, say, a swimming pool, a pH of 14 would not make that pool a safe place to swim.

So in your stream and lake, what would be unhealthy? Damaging to local people, aquatic life, local geology etc.

For many parameters this is easy, radiation, high or low pH, high concentrations of mercury etc. but alkalinity is very different from these.

I hope that I can help you and direct you to a useful resource for your questions.

[MegaKeeperMan]

Thanks for the link, mate. Read through it but it unfortunately doesn't answer my questiom.

I have not really understood the question.

I am a Public Analyst and one of my areas is water analysis. Unfortunately this scope does not include lakes.

I think what would help me would be if you explained to me your definition of "healthy" on reference to any parameter that you could be measuring.

Obviously in the case of, say, a swimming pool, a pH of 14 would not make that pool a safe place to swim.

So in your stream and lake, what would be unhealthy? Damaging to local people, aquatic life, local geology etc.

For many parameters this is easy, radiation, high or low pH, high concentrations of mercury etc. but alkalinity is very different from these.

I hope that I can help you and direct you to a useful resource for your questions.

Sorry, I probably should've been more specific. When I say healthy levels of alkalinity, I mean; what are good levels of alkalinity in these bodies of water to be able to withstand acidification, from example acidic rain. A question could be: Would a lake with an alkalinity of 30ppm (0.6mEq/L) be vulnerable to acidic rain? Does that make my question clear?

[Archer]

Yes, that's much clearer now. Did to measure the pH and conductivity (or total dissolved solids, TDS) while you were sampling?

You need these values to determine the buffering capacity of the waters

[MegaKeeperMan]

Yes, that's much clearer now. Did to measure the pH and conductivity (or total dissolved solids, TDS) while you were sampling?

You need these values to determine the buffering capacity of the waters

I only measured the pH. The initial pH for the lake was 7.5, titrated down to the target pH of 4.56 which was when the sudden shift in color occurred. The stream had a pH of around 7 and was as well titrated down to 4.56.

I have no idea if it'll be of any use but I'll provide the instructions I used to complete this task, I used the same chemicals the article used except for the indicator, which was bromcresol green and not bromcresol green-methyl red.

Instructions: http://www.wetnewf.org/pdfs/measuring-alkalinity.html

[Archer]

Ok, no problem with the TDS.

I should explain why my answers are somewhat haphazard, I test these parameters on drinking water so I am having to think about how to relate this to environmental chemistry.

This link is quite interesting http://www.water-research.net/Watershed/alkalinity.htm

This link gives you some ranges for different waters

http://swrp.esr.pdx.edu/publications/manual/alkalinity_introduction.pdf

[MegaKeeperMan]

Ok, no problem with the TDS.

I should explain why my answers are somewhat haphazard, I test these parameters on drinking water so I am having to think about how to relate this to environmental chemistry.

This link is quite interesting http://www.water-research.net/Watershed/alkalinity.htm

This link gives you some ranges for different waters

http://swrp.esr.pdx.edu/publications/manual/alkalinity_introduction.pdf

Thank you for those links! Perfectly answers what I wanted to know! Thank you for the effort you put in, mate, really appreciate it !

[Archer]

It's my pleasure to help, we got there in the end.

Please come back and visit us again if you need any more help with chemistry.

Kind regards

Archer