Interesting local water chemistry

[Fishdude]

I found a basic chemistry analysis from my local water authority that I thought would be informative to post here for people wondering about TDS and the differences in tap water. I live in the middle of Pennsylvania and thus our local water authority draws water from drilled wells in different parts of town and delivers treated water to homes and businesses that comes with very different profiles based on your location. Here's a breakdown of some interesting numbers that are different between two wellfields that are only a few miles apart. My current house draws from one and the house I'm moving to in July draws from the other.

• Hardness - 115 mg/L vs 251 mg/L
• Calcium - 24.9 mg/L vs 60.7 mg/L
• Magnesium - 12.8 mg/L vs 24.2 mg/L
• Nitrate - 1.48 ppm vs 4.4 ppm
• Total Dissolved Solids (TDS) - 99 mg/L vs 331 mg/L
• Total Coliform (bacteria) - ND (not detected) vs. 66.8 mg/L

So as I said these wellfields are within a few miles of one another and the house we're moving to is just up the road. Based on this analysis the water I'm using now vs. what I'll be using in my fish room are very different. One well is at a slightly higher elevation and the other is essentially in karst limestone. We're going from water that's perhaps moderately hard to some that creates limescale on every surface it touches (crazy hard water). In the fish room I'll be cutting the water from the wellfield with RO/water so it should make it a better match with the species of fish I intend to keep. If you can find similar analyses for your water I encourage you to look it up because it makes a huge difference!

 

[KBOzzie59]

So are these different treatment plants as well?

[Dwayne Brown]

Wow thats really cool @Fishdude I live in seattle and we along with most of western washington get our fresh water from a rain and snow that melts into resevoires. So my water is super soft ot that good for livebearers but great for other south american fish.  

[lefty o]

good news is most fish and plants will adapt to the change. would be nice if you can do a slow taper from one water to the other vs making a move and instant change. it is amazing how wells close together can have big differences in water make up.  even ones within a few hundred yards of each other can have large differences depending on where they hit the aquifer. 

[Fishdude]

32 minutes ago, KBOzzie59 said:

So are these different treatment plants as well?

Essentially, yes. There is no filtration for a number of the wells in the surrounding region, but the water coming from an above ground stream and two of the original wells goes through a big treatment plant and filtration. This serves most of the original population center of the town, but as the area expanded they drilled new wells and simply treat with chlorines at pump stations. 

[Fishdude]

Here's their map of our region and the sources of water for various parts of town. Keep in mind this is a college town of about 45,000 permanent residents and another 43-45k college students. Not a huge region.

 

Edited April 5, 2021 by Fishdude

[Biotope Biologist]

That's awesome! 

 

In Bellingham, WA the water treatment center was so proud of their water quality they would send test results in the mail every other week. They used to have some of the best water in the nation.

 

I do remember testing people's well water from about 10 miles north and it being very different based on where the well sat. In Washington every where that isn't a city is farmland so you can get some wild readings.

[OnlyGenusCaps]

Well water is weird for sure.  Thanks for sharing that!

I'm on a well, which is nice in terms of not having to deal with dechlorinator.  But we are fairly hard here, about 325 mg/L.  Quite a bit of iron in there too.  But still I feel pretty lucky.  We don't have much Mg which is harder to deal with in some ways.  Also we live just outside of a PFAS plume, and I'm wildly glad I don't have to deal with that stuff!  Plus, just a bit north of us everyone has a surprising amount of As in their water.  We've got none.  So, I agree variability seems to be the order of the day for well water.

Interesting they don't pool the water and treat in in State College.  The cities in well around here typically combine sources and treat it as a unit.  I wonder why the difference?  Sadly the answer to that is far, far more about municipal water treatment practices than I am familiar with.