Water Quality - Totally Off Topic

[Mr. Bloom]

Years ago, I actually read the annual water quality report that came with our bill. I recall a comment indicating that federal standards allowed for chlorophyll coloring in the water...which I took to mean it could be a bit green.

Other than a brief visit to Greenville Mississippi where the water is "tea colored" , I had never in my life seen coloration in tap water. When we moved to a semi-agricultural area of Southern Indiana, I noticed a tinge of color in the jacuzzi...which prompted me to read the water quality report...but it never bothered me.

Tonight, I'm staying in the heart of downtown Indianapolis. My room has a garden tub...and I took a hot bath in the squeaking clean, white tub.

Guess what! Very green tinted water! In the heart of the 12th largest city in America!

So, it got me thinking...is the coloration due to organic matter in the water or due to refraction of light?

[crazycanuck]

Hmmm..umm..I have no idea

I've not seen funny coloured water since i visited my aunt in Smoky Lake, Alberta years ago..

I hope someone will be able to help ya Mr S..If not, your friendly local water dept might have the answer.

C

[bmccasland]

Mr.Sliver - there's probably *something* in your water. Although most algae doesn't grow very well in chloronated water.

Come down to the bottom of the Mississippi and share a glass with me! We drink the treated/resued water from 1/3 of North America, farm run-off, and for final seasoning there's petroleum/chemical alley just up river. Thirsty yet?

[solobiker]

In the spring and fall if the water treatment plants change their source water, which they often do, that could change water quality. And in the spring and fall, if wherever the water comes from also changes because the water in the lakes turn over. That would be my and DH's thoughts. He is a water engineer, and I grew up on the water and saw the changes seasonally. High tannins (tea colored) in the water mixed with chlorine (for disinfection) can created harmful byproducts (cancer causing). These byproducts also have to be monitored. All of this could be less of an issue depending upon what your municipality uses for disinfection of the water (chlorine gas, hypo-chlorite, ozone, etc) Also what type of pipes are in the hotel. Old rusted galvinized pipes. I am sure you know that , Well that is all I have for you.

[singletrackmind]

Water quality reports for some areas can be found online...might do some snooping if you're in the mood.....or feeling daring.

[boy in a kilt]

Chances are if you didn't get burns from the water, and aren't sick then anything that could've been in the water probably won't kill you for another twenty years. By that time you will have forgotten about green water in a bathtub.

Now, for a quick primer on water color (my MS thesis was in Optical Oceanography).

Water color depends on the wavelength of the scattered light. The absorption spectrum of water peaks in the red wavelengths (to include infrared which has a bunch of other ramifications) and has a minimum in the blue wavelengths.

As light passes through water, the red gets absorbed first and the blue gets absorbed last. Whatever wavelength is left after it makes the trip from the source to your eyes is the color you see. If both you and the light source are above the water surface, it's a round trip. Any other combination is basically a one-way trip.

For the nerds in the audience, the scattering mechanism is largely due to vibrational modes of the water molecule and is therefore, inelastic.

Coloring due to other stuff like chlorophyll and dirt is due to a combination of the scattering and absorption of the material in the water.

[sandra]

Mr. Silver, we moved here almost 20 years ago from right outside of Greenville. We had that colored water way back then! It stained everything!