1. Monitoring Nitrification
Understanding the biological event
Monitoring Nitrification

2. What is nitrification
Biological process by which free ammonia is converted to nitrite and then nitrate.
Free ammonia NH3 is converted to nitrite NO2
Nitrite NO2 is converted to nitrate NO3
These compounds are actually primary drinking water contaminates but at the Point of Entry (POE) of the system only
Nitrite 1 ppm
Nitrate 10 ppm

3. Why are we concerned with nitrification
Creates unwanted byproducts
Nitrite
Nitrate
Source of taste and odor complaints
Consumption of disinfection
Problems with Total coliform compliance
Lead and copper Rule Compliance
Microbial Induced Corrosion

4. Nitrification Precursors
Food--- Ammonia
Biology
AOB or Ammonia oxidizing bacteria Nitrosomonas
NOB or nitrite oxidizing bacteria Nitrobacter
Disinfection or, more to the point
Lack of disinfection

5. Where does the ammonia come from?
Naturally occurring in ground water
Run off in surface water
Added to form chloramines
Released from the chloramine in the system as a result of either biological demand for disinfection or decay of the chloramine molecule due to water age.

6. Source of AOB and NOB Nature Exists in biofilm in distribution lines
Total coliform tests gives no direct read of AOB or NOB

7. What are we going to monitor?
Total chlorine
Monochloramine
Free Chlorine
ATP Biological indicator
Nitrite
Nitrate
Free Ammonia
Alkalinity
ORP

8. How will the parameters move?
At the beginning of the event
Total and mono chlorine will start down
Free ammonia can actually start to rise
ATP will start up
Free chlorine will remain very low
Alkalinity and ORP will start to drop

9. As we go along Total and mono will continue to drop
ATP will continue to rise
Nitrite will start to appear
Free ammonia will begin to drop
Alkalinity and ORP will continue down

10. Full blown event Free, Total and Mono chloramine all but gone
ATP can actually peak out and start to fall
Free ammonia will fall
Nitrite will continue to rise, peak out and then start to fall
Nitrate will appear and start to rise
Alkalinity and ORP an continue to drop

11. All generally speaking of course

13. Remember! We are monitoring a biological event
If you depend on the residual drop, the event may have already started!
If you depend on the appearance of the by products, the event is well advanced in it’s progress
If you wait for the nitrate to appear……..well…..to late

14. Relevance of each parameter
Any single parameter, used alone, is useless!
Free and total chlorine are the easiest to run.
Nitrite, free ammonia and monochloramine tend to get a little more time consuming depending on the method.
Alkalinity and ORP are new tools in my arsenal

15. Biological Tools- Plate Counts
Heterotrophic or other plate counts
Traditional and been around a long time
Time consuming. Several days to get results that have meaning
Like coliform, are pretty much only going to find what they are looking for

16. ATP-Adenosine Tri Phosphate
ATP is the energy carrying molecule in every cell
By extracting and measuring the amount of ATP in a given sample you can quantify the level of total biological activity.
This can be done in a matter of minutes either in the field or laboratory environment
ATP technology is referenced in AWWA Manual M 56 as a protocol that is receiving increasing acceptance
I use Luminltra Technologies, Fredericton, New Brunswick, Canada 2nd Generation ATP technology

17. All Parameters Considered
Relying on the movement of any one parameter cannot tell you where you are in the event
The whole process is biological.
Thru ATP testing you can get an idea early on the trouble is coming and you can tell when you have recovered.
Monitor a biological event with biological testing

18. Thank You
Bill Travis