River Water Quality

[zdas04]

I teach a class that includes a section on Oil & Gas industry Produced Water Disposal. The class is very much U.S.-centric, but I teach it in international locations.

One of the slides compares Water Quality standards, to a local river near my home, to the quality of produced water in a CBM (Coalbed Methane or Coalseam Gas) field. I was looking to change my example river from U.S. to somewhere on another continent, but I've been unable to find a Cation/Anion analysis with TDS, pH, and turbidity for a major river. I'd like to use the Thames, Danube, Nile, Amazon, or the Yangtze, or any river that has wide recognition around the world, but I have been wildly unsuccessful finding any gross-level information on any major river that is used for a municipal water supply. I can find a lot of information about the specific trace elements that people are concerned about today, but not Sodium or pH.

Does anyone have an example water analysis from a major river that they would be willing to share? Thank you.

David Simpson, PE
MuleShoe Engineering

http://www.muleshoe-eng.com

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

"It is always a poor idea to ask your Bridge Club for medical advice or a collection of geek engineers for legal advice"

 

[bimr]

http://www.thameswater.co.uk/water-quality-reports/z0304-READING-WEST-SOUTH-AND-CENTRAL.pdf

http://www.dwi.gov.uk/about/annual-report/2007/Thames.pdf

If you want more details than this, you can send an email to the water supplier.

 

[zdas04]

Thank you bimr. The annual report was interesting reading, but all the data was number of exceedences within water supplies. I have to think that the Water Quality Reports were after municipal treatment (I saw a jar of Thames River water in London last month and the turbidity was certainly greater than <0.1 FTU, it wasn't horrible, but it wasn't crystal clear either).

David

 

[bimr]

It appears that the only parameters that would show appreciable change from raw water to finished water are the turbidity and chlorination.

 

[ch81pc]

Thames as measured at Oxford yesterday (flow rate 1398.4Mld)- Nitrate 6.2mgl, Ammonia <0.01mgl, Turbidity 2.9 NTU. pH 8.37.

Min and max results this year:

Nitrate <0.1mgl 10.1mgl
Ammonia <0.01mgl 0.27mgl
Turb 1.9NTU 65.9NTU
pH 7.89 8.98

 

[zdas04]

Any idea what TDS goes with those readings?

David

 

[ekolog16]

The Vardar River in Skopje measured in July 2009 was:

Temp = 18.4 deg C
pH=7.11
NO3= 0.287
NH3=2.416 mg/L
Turbidity = 7.5 NTU
TSS=20 mg/L
TDS= 8 mg/L
BOD= 7.95 mg/L O2
DO=4.07 mg/L

No flow data, but average flow in 7/2008 was 11 m3/sec (or 228 MGD).

http://meteo.gov.mk/EkologijaVodaCharts.asp?Par=27&God=2009&Mes=7&B1=confirm&X=1

 

[zdas04]

Thank you. I am having a hard time with those TDS numbers. The EPA limit for drinking water in the U.S. is 500 mg/L, and the pristine fishing river near here usually runs 250 mg/L (with a turbidity of 3.5). The Varder has 8 mg/L TDS, 20 mg/L TSS, and 7.5 turbidity. With that turbidity I'd expect the numbers to be g/L instead of mg/L. The Thames data that bimr pointed me to was similar to the Vardar.

I guess I'm going to have to dig into this further.

David

 

[bimr]

This document may assist you:

http://www.icsu-scope.org/downloadpubs/scope42/contents.html

 

[zdas04]

That was interesting bimr. The summary chapter has a table of total volume and total dissolved solids. Dividing the two for the whole world shows 130 mg/L as the global average. I looked at 20 individual rivers and got numbers between 100 and 350 mg/L which is what I expected. The single digit numbers in other reports are confusing me.

David

 

[ekolog16]

zdas04,

Sorry about that, the numbers for TDS/TSS I posted I'd read wrong.

In 7/09 in the Vardar:
TDS (Total Filterable Residue) was 365 mg/L
TSS (Total Non-Filterable Residue) was 385 mg/L.

Please ignore the previous TDS and TSS values.

ekolog

 

[zdas04]

Thanks for clearing that up. I thought TDS would be the non-filterable part (since it is disolved) and TSS would be the filterable part (since it is suspended).

David

 

[ekolog16]

I think filterable means the sample is filtered and then the mass of solids is determined after evaporating a certain volume of water.

http://www.hach.com/fmmimghach?/CODE:DOC316.53.0124615783|1