Analytical Methods for Bathing Water Analyses

Garden State Laboratories, Inc. is certified by the NJDEP for the bacteriological analyses required for swimming pools, aquatic facilities, lakes, beaches, whirlpools, spas and hot tubs.

POOLS, AQUATIC FACILITIES, AND WHIRLPOOLS

 

Total Coliform (TC) is the analysis for Coliform bacteria within a 100ml water sample collected from a designated swimming pool or aquatic facility.  These bacteria are an indicator group of different species which are collectively referred to as “Coliform”.  N.J.A.C. 8:26 requires that Coliform bacteria not be present in the water sample.

 

Garden State Labs performs the Colilert-18 and Colilert analytical methods, which indicate a Present or Absent result of Coliform bacteria.

The Colilert-18 and Colilert methods provide Total Coliform results in 18 and 24 hours (respectively) from the time of set-up in the lab. These are the latest analytical methods certified by the NJDEP, and provide rapid results compared to the older LTB method turnaround of 48 to 96 hours.

 

Pseudomonas aeruginosa (Ps. a) is the analysis for the organism Pseudomonas aeruginosa within a 100ml water sample collected from a whirlpool, spa, or hot tub.  N.J.A.C. 8:26 requires that Ps. a not be present in the water sample.

 

Garden State Labs performs the Pseudalert analytical method, which indicates a Present or Absent result of Ps. a bacteria.

 

The new Pseudalert method provides Pseudomonas aeruginosa results in 24 hours from the time of set-up in the lab.  This is the latest analytical method certified by the NJDEP, and provides rapid results compared to the old membrane filter method which took 72 hours.

Heterotrophic Plate Count (HPC) is a count of the total bacterial organisms present within 1ml of water sampled from a pool, aquatic facility, hot tub, spa, or whirlpool.  N.J.A.C. 8:26 requires that the total count not exceed 200 organisms per milliliter.  This test is also known as the Standard Plate Count (SPC) and the Aerobic Plate Count.

 

Garden State Labs performs the SM 9215B analytical method, which provides a result ranging from <5 organisms (None detected) to >57,000 (too numerous to count).

 

The Heterotrophic Plate Count incubates for 48 hours from the time of set-up in the lab.

LAKES

 

E. coli is the analysis for the organism E. coli within a 100ml water sample collected from a Lake or River.  N.J.A.C. 8:26 requires that E. coli not exceed 320 organisms per sample.

 

Garden State Labs performs the Colilert-04 MPN analytical method, which provides a result ranging from <1 organism (None detected) to >2,419.6 (Too numerous to count).

 

The Colilert-04 MPN method provides E. coli results in 24 hours from the time of set-up in the lab.

 

E coli is a direct fecal indicator.  E. coli is the latest analysis included in recreational bathing water testing.  Prior to 2018, lake bathing waters were analyzed for Fecal Coliform.  The Fecal Coliform analysis is no longer performed.

MARINE WATERS

 

Enterococcus is the analysis for the organism Enterococcus within a 100ml water sample collected from an ocean water source.  N.J.A.C. 8:26 requires that Enterococcus not exceed 104 organisms per sample.

 

Garden State Labs performs the USEPA 1600 analytical method, which provides a result ranging from <10 organisms (None detected) to >600 (too numerous to count).

 

The USEPA 1600 method provides Enterococcus results in 24 hours from the time of set-up in the lab.

Enterococcus is a direct fecal indicator.