Fecal Accident

[flintstone]

The winter winds blew a small amount of pet fecal matter into my pool. I was able to retrieve most of it, bit some disintegrated as it was being removed. I tried to increase my SWG setting, but with water temps below 50 degrees, it is not able to produce any chlorine.

I've read some of the posts regarding this topic, but still could use some immediate advice. Yes, I'm freakin' out.

I have never used bleach because of the SWG. What should my target level of FC be? How much bleach should I use to bring the FC to an appropriate level? Would any other disinfectant be more appropriate? Do I need to remove and clean or replace my cartridge filter medium?

My current readings are as follows:

FC: 6.2
CC: 0
pH: 7.5
TA: 80
CYA: 45 (I dumped some water following a recent rainstorm.)
CH: 450 (My water has always tended toward high CH.)
Water temp: 48

 

[New2Me]

Chillax-Chlorine doesn't care if the matter is fecal, floral or food, it will kill it just the same. Maintain your FC, watch for CC, with temps of 48, by the time that the water is warm enough to get in, all will be good. Your filter will be fine. You can add enough bleach to shock, but I wouldn't bother. Every year I open there is a ring of dead worms in my pool; I clean them as best I can and then shock per normal opening procedures.
Happy Holidays!

 

[waste]

Sorry this happened You were able to remove most of it manually which is good! Are you still swimming? The trouble with feces is if you are exposed to them. You would do well to add 3 gal of ~10.5% bleach and let circulate for 4 hours, then add another gallon and circulate for another 2. The stuff I've read is about human fecal matter, but you need to get the chlorine up for a few hours (some of the pathogens have slow kill times, even with high chlorine) and I recommend redosing a little just to be sure (cat poop can carry 'toxio - something or another', which - once it's in the human body stays there (a healthy immune system keeps it from being problem, but if the immune system goes down, for whatever reason, you could get very sick or die )

I'm going out of memory here and am not a doctor but I believe if you follow the above, the water should be safe to swim in again

As New2me said - Happy Holidays! (NOT crappy holidays )

 

[New2Me]

Also, form the pool calculator
http://www.poolcalculator.com/
your shock level is 16 with a CYA of 45. With a current FC of 6.2 you would need to add 406 oz.s of 6% bleach to get there.

 

[chem geek]

Realistically, the only issue with fecal matter is whether it contains protozoan oocysts, specifically Giardia or Cryptosporidium. Without these, any bacteria or viruses will be killed fairly quickly, especially if you've removed physical matter and the rest is dispersed and exposed to chlorine. Unfortunately, the protozoan oocysts are very resistant to chlorine. The official CDC Fecal Incident Response Recommendations for Pool Staff has Giardia with a CT value of 45 and Crypto with a CT value of 15,300. In an SWG pool with an FC that is about 5% of the CYA level, the effective FC level with no CYA is 0.05 ppm. So that means the germ inactivation time to kill 99.9% of Giardia is 900 minutes or 15 hours. For Crypto, it's over 7 months so essentially not killed. This assumes no germicidal effect from the chlorinated cyanurates and that's a reasonable conservative assumption given the CDC data.

In your current pool with an FC of 6.2 ppm and a CYA of 45 ppm, this is roughly equivalent to an FC with no CYA of 0.1 ppm so a 99.9% kill time for Giardia of around 8 hours (if the water temp were 77F -- yours is colder so kill time would be longer).

Odds are that unless your pet had diarrhea then it is less likely that it has a protozoan parasite in its fecal matter in large numbers. Also, you'll note that the guidelines assume that formed stools are much less likely to have Crypto. The CDC Annex for Module 6.5 of the Model Aquatic Health Code (MAHC) shown here describes how 300 samples of formed stool fecal incidents in public pools were analyzed and none had Crypto but 4.4% had Giardia.

If you were to use chlorinating liquid or bleach to raise the FC to the normal shock level of around 40% of the CYA level, then this is equivalent to an FC with no CYA of around 0.6 ppm, assuming you lower the pH before adding the chlorine to prevent the pH from rising too much. That would then kill 99.9% of Giardia in around 75 minutes. Given that this fecal matter was from a dog and not a human and given that it was not diarrhea, you could probably not shock and just wait one day, stay out of the pool, and keep the pump running for 24 hours and then be fine.

Richard

 

[flintstone]

I appreciate your help and encouragement. The offending doggie doo was well-formed, so I should be O.K. I've dosed the pool and will continue to check my numbers. Thanks.