Fecal Matter in Your Pool Stinks!

Following the CDC guidelines for a fecal accident is important to help reduce the risk of a Recreational Waterborne Illness (RWI). As indicated in the guidelines, there is a difference in bacterial contents of formed stool vs diarrhea, which determines the action required by staff.  A Formed stool may contain no germs, a few, or many that can cause illness. The germs that may be present are less likely to be released into the pool or spray ground because they are mostly contained within the stool, but prompt removal of stool is necessary. A Diarrheal stool (liquid) is a higher-risk event for contamination of pathogens such as Cryptosporidium (or “Crypto”) which is an extremely chlorine-tolerant parasite. To disinfect the water following a diarrheal incident, aquatic staff must hyper chlorinate, raising the free chlorine concentration elevated for a long period of time. 

Fecal accident Steps

FORMED STOOL Steps:
1. Direct everyone to leave the pool and close the pool
2. Remove as much fecal material as possible using net and/or gloves trying to keep stool intact.
3. Maintain chlorine at minimum 1 ppm and pH 7.5 or less
4. Maintain chlorine and pH at those levels for at least 45 minutes
5. Ensure fecal incident log is complete before opening.

DIARRHEAL STOOL Steps: Non-stabilized Chlorine (No Cyanuric Acid)
1. Direct everyone to leave the pool and close the pool.
2. Remove as much fecal material as possible VACUUMING FECAL MATTER FROM THE WATER IS
NOT RECOMMENDED
3. Raise chlorine to 20 ppm and maintain pH 7.5 or less
4. Maintain chlorine and pH at those levels for 13 hours
5. Ideal water temperature 77°F or higher and ensure filtration system is operating during the
hyperchlorination process.
6. Backwash filter
7. Return chlorine to normal operating range. Bromine pools must increase the chlorine level to
20ppm. This is because bromine does not kill cryptosporidium.
10. Ensure fecal incident log is complete before opening.
*CDC recommendations found here.

DIARRHEAL STOOL Steps: Stabilized Chlorine (Cyanuric Acid, dichlor, and trichlor)
1. Direct everyone to leave the pool and close the pool.
2. Remove as much fecal material as possible VACUUMING FECAL MATTER IS NOT
RECOMMENDED.
3. Lower cyanuric acid to 1-15 ppm (draining)
4. Maintain a pH of 7.5 or less
5. Ideal water temperature 77°F or higher and ensure filtration system is operating during the
hyperchlorination process.
7. Maintain Chlorine level using one of 3 Options
- Raise free chlorine to 20 ppm and maintain it for 28 hours
- Raise free chlorine to 30 ppm and maintain it for 18 hours
- Raise free chlorine to 40 ppm and maintain it for 8.5 hours
8. Backwash filter
9. Return chlorine to normal operating range
10. Ensure fecal incident log is complete before opening.
*CDC recommendations found here.

Hot tubs/spas, and some splash pads can have much smaller amounts of water. In response to formed
or diarrheal fecal incidents in these small-volume venues, it might be more efficient to completely drain
as much water as possible from the venue and associated plumbing; scrub and clean all accessible
surfaces in contact with contaminated water; replace or clean filter media when appropriate, and refill
with uncontaminated water from an approved source (for example, municipal water system).