Interpreting lab report?

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Bwdonohues58

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In The Industry
Apr 22, 2019
129
Homer, AK
Pool Size
10300
Chlorine
Liquid Chlorine
I just received the report shown in the photo for testing my pool water. The lab simply said that the results were acceptable under the current State regs. I have these tests done once a month. I would like to know if an HPC of 4 is considered a low level of bacteria? I looked it up and it looks like the maximum allowable is 100 MPN/ml. I really don’t know how to read these reports. Any help would be appreciated. This is an indoor pool with FC around 3.0. ORP of 750 plus or minus.
650A18B8-39D4-4336-AB39-2F858D0A5723.jpeg
 
Here's what they go by. I was wrong, the maximum HPC is 200, not 100. This is the regulation for the Municipality of Anchorage where the test lab is located.

"Samples of pool water shall be collected at least monthly while the pool is in use, at a point near the outlet of the pool, and at any other points designated by the department. The department may increase the frequency of pool water sampling if necessary to assure that the pool water meets the standards of this section. AMC 16.15.190(b) Routine samples collected under (b) of this section may not: (1) contain more than 200 bacteria per milliliter, as determined by the standard (heterotrophic) agar plate count at 35 degrees C; or (2) show positive test (confirmed test) for coliform organisms in any of the five 10 milliliter portions of a sample, or when the membrane filter test is used, show positive test (confirmed test) for more than zero coliforms organisms per 100 milliliters AMC 16.15.190(c) *** E-mail the receipts indicating water samples has been submitted by the 23rd of every month until notified to stop."
 
Here is the verbatim regulation:
16.15.190 Water, wastewater, and solid waste. A. Potable water shall be provided from a source approved by the department. The water supply shall be adequate for the purposes of the facility and shall meet the standards of 18 AAC 80. B. Samples of pool water shall be collected at least monthly while the pool is in use, at a point near the outlet of the pool, and at any other points designated by the department. The department may increase the frequency of pool water sampling if necessary to assure that the pool water meets the standards of this section. C. Routine samples collected under B. of this section may not: 1. Contain more than 200 bacteria per milliliter, as determined by the standard (heterographic) agar plate count at 35 degrees C; or 2. Show a positive test (confirmed test) for coliform organisms in any of the five 10 milliliter portions of a sample, or when the membrane filter test is used, show positive test (confirmed test) for more than zero coliforms organisms per 100 milliliters. D. Samples of pool water shall be collected and examined in accordance with the American Public Health Association's Standard Methods for the Examination of Water and Wastewater, 16th Edition, 1985. E. If a sample of pool water tests positive for pseudomonas or other pathogens, the pool shall be closed until sampling shows that the water is free of the pathogen. F. Samples of pool water shall be examined by a laboratory approved by the department. G. If chlorine is used as a disinfectant, the level of free chlorine shall provide a molecular hypochlorous yield of not less than 0.3 mg/l. The yield shall be determined either mathematically or by using the graph in Table E of this subsection.
 
If the lab is saying that the numbers are out of limits, they are the ones who need to explain why they are saying that including references to the rules they are relying on.

In any case, I thought that you said that you were not regulated?
 
I am not regulated, but I want to be in compliance. Just think it’s safer that way. What I really want to know is if there is anybody on TFP who regularly gets pool water tested for bacterio, HPC. I just would like to compare notes. See how I’m doing. That all.
 
Interesting thread... HPC is not a very useful measurement for pool safety since it's so general. It includes plate counts of bacteria, yeasts, molds and probably fungi. Coliform tests are much more useful since they are indicators of human feces contamination and this is always a concern for water supplies. But they are not easily tested by pool owners since testing require incubators and other lab equipment so pool tests for residual FC are used to infer harmful bacteria cannot survive since the time to kill is so short if properly chlorinated.

I'll watch with interest to see if there's anybody that actually knows what's living in their pool.

Chris
 

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No problem. I read that there are over 300,000 public pools in the US and I am fairly certain that each operator is required to have the bacteria measured monthly via HPC test at an approved lab. I thought that perhaps some of them might be on TFP, but I guess not. The Alaska maximum HPC level of 200 is higher than in other states and countries. In Alberta and Queensland Australia, the max allowable is Heterotrophic plate count is 100. The regulators are not interested in Free Chlorine levels. They want to know if there are bacteria in the pool (along with e-Coli and coliform bacteria). That's all they test for. I am fairly certain that my pool's level of 4 (when the max allowable is 200) is very good but I really would like to get in touch with another operator to compare notes, sampling methods, etc.
 
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Bwdonohues58 said:
I thought that perhaps some of them might be on TFP, but I guess not.
Click to expand...

TFP focus is on homeowners with residential pools. TFP methods often conflict with commercial operator training and requirements.
 
setsailsoon said:
HPC is not a very useful measurement for pool safety since it's so general. It includes plate counts of bacteria, yeasts, molds and probably fungi. Coliform tests are much more useful since they are indicators of human feces contamination and this is always a concern for water supplies
Click to expand...
The report I copied in my first post shows they also tested for E-Coli and Coliform (both less than 1). BTW, Amazon sells very cheap DIY tests for e-coli and coliform. I've used them and they work fine. No incubator is needed. Made by Aqua Vial. Just open the test tube, fill the tube with pool water to the line, re-cap, and set it aside for 48 hours. It indicates fecal bacteria if the color turns from yellow to various shades of red. They give you a color chart for comparison. Not official, but it gives peace of mind if some "questionable individual" gets into the pool. The HPC tester by HACH ($178.00), requires an incubator ($200) and a $300-plus eyedropper. I'm not going for it. I like to have the official monthly reports on hand just in case somebody asks about the water.

https://www.amazon.com/AquaVial-Col...jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==
 
Who is asking about your pool water, are you a business and therefore have a mandate for this test.. If not there is no reason to do the test and just a waist of money... It is better to follow the TFP standards and know you have nothing growing in your water..

What type of test kit do you have and what are your numbers :)
 
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