PHSS_10123_How to Collect A Water Sample 2023
Background
HOW TO COLLECT A WATER SAMPLE
“Coliform Bacteria” is a general term used to describe a group of bacteria whose presence indicates contamination
of a water system. Certain types of coliform, such as E. coli, are capable of causing illness in humans. Thurston
County recommends that private well owners test their water at least once a year for coliform bacteria and once
every three years for nitrates.
When and Where to Pickup Sampling Bottles and Submit a Sample for Testing
PICK UP EMPTY BOTTLES FOR TESTING AT:
• 3000 Pacific Ave SE, Olympia 2nd Floor at Environmental Health • (360) 867-2673
Mon-Fri 8am-4pm
You have the option to prepay at this location with cash, check, credit card (MC, VISA).
• Public Health Building, 412 Lilly Rd NE, Olympia • (360 )867-2500
Mon-Fri 9am-4pm
DROP OFF BOTTLES FOR TESTING AT:
• Thurston County Courthouse Building 1, 2000 Lakeridge Dr. SW, Olympia at the courtyard entrance off breeze way.
The drop box is located on the bench to left of the door • (360) 867-2631
Mon-Wed 8-5 and Thurs 8-12:30
• 3000 Pacific Ave SE, Olympia 2nd Floor at Environmental Health • (360) 867-2673 • Mon-Wed 8-1
• Public Health Building, 412 Lilly Rd NE, Olympia • (360 )867-2500 • Mon-Wed 9-1
If not prepaid, attach a check for $32.00
Please note: On Fridays, no water samples are accepted.
When returning samples to the locations below, the water sample must be collected Tuesday morning and dropped
off no later than noon on Tuesday. Because these sites do not collect fees, when you return the sample, attach a
check for $32, payable to TCEH.
• Rainier Town Hall, 102 Rochester St W • Rochester (R.O.O.F.), 10140 Highway 12 360-
446-2636 360-273-6375
PICK-UP: Monday–Thursday, 8 am–5 pm PICK-UP: Mon–Fri, 9:30 am–5:30 pm DROP-
DROP-OFF: Tuesdays only, 8 am–noon DROP-OFF: Tuesdays only, 9:30 am–noon
• Tenino City Hall, 149 S. Hodgden • Yelm Public Works, 901 Rhoton Rd. SE
360-264-2368 360-458-3244
PICK-UP: Tuesday–Friday, 8 am–4 pm PICK-UP: Monday–Friday, 8 am–5 pm
DROP-OFF: Tuesdays only, 8 am–noon DROP-OFF: Tuesdays only, 8 am–noon
DELIVER YOUR SAMPLE FOR TESTING ON THE SAME DAY THAT YOU COLLECT IT.
Nitrate Samples Only Accepted on Monday and Tuesday
Complete Lab Form
Fill out the lab form completely down to the “DRINKING WATER RESULTS” section, pressing firmly with a black
pen. Be sure the form is filled out COMPLETELY including the CORRECT DATE AND TIME OF COLLECTION.
• For a private well sample, under “Type of Sample”, mark #4 “Sample Collected for Information
Only”.
• For a well that serves two homes, under “Type of Water System”, check “Other” and write two- party;
under “Type of Sample”, check #1 “Routine Distribution Sample”.
• For a Public Water System (3 or more homes), under “Group A and Group B Systems”, provide the system
ID# and name of the community water system (if you don’t know the number, call the Environmental Health
Dept); under “Type of Sample”, check #1 “Routine Distribution Sample”.
Keep Sample Bottle Sterile
Your sample bottle has been sterilized. For accurate testing, it is important to keep if free from contamination. If
you accidentally contaminate it, please return it for another sterile bottle. Do not boil the bottle or put anything
inside it except your sample.
• You may see moisture or white powder in the bottle—it is supposed to be there.
Do not put tape, or in any way mark or write, on the bottle
DO NOT Heat Your Sample
Keep your water sample out of the sunlight and heat, especially when transporting it in your car. If it
will take more than an hour to deliver your sample for testing, we recommend transporting it in a
cooler with ice. A warm sample can change your sample results.
Sample Collection
1. Select a faucet in the kitchen, utility room or bathroom (avoid single handle faucet that mixes hot
and cold or a spray type faucet). Non frost-free outdoor faucets are also acceptable.
2. Remove any filters or screens from the faucet tap.
3. Turn on the cold water and let it run for at least five minutes. Turn off the water.
4. Disinfect the tap by scrubbing the exposed tap with a small brush dipped in a mild bleach solution.
Use a standard bleach, one without fragrance of dye with a sodium hypochlorite concentration of
5.25% or greater, mixing approximately 1/8th teaspoon per 1 cup of water.
5. Turn the cold water back on to an even low flow, remove the cap from the sample bottle and
collect your sample as described below.
OR ABOVE
Leaving an air space
DO NOT SET THE CAP DOWN OR TOUCH THE INSIDE OF
THE CAP OR BOTTLE. FILL THE SAMPLE BOTTLE TO THE
100 ml LINE.
6. Re-cap the bottle and deliver to the lab as soon as possible.
Reporting of Results
You should receive test results by mail within a few days of when you submit your sample. If your
sample shows contamination, we will call you with the results immediately and mail well disinfecting
instructions with your report. Those instructions are available on our website at
www.co.thurston.wa.us/health/ehdw.
Collecting Other Samples — Lakes, rivers, reservoirs, swimming pools
Select a spot where a representative sample can be taken. Remove the cap from the sample bottle
and collect the sample by submerging the bottle completely in the water. Do this in a continuous
sweeping motion, extending the mouth of the bottle into the water and sweeping to a depth of
approximately 1 1/2 feet. Continue the sweep to the water surface and above. Carefully pour off the
water above the shoulder of the bottle, and then replace the cap without touching the mout h of the
bottle. Submit non-drinking water samples Monday through Thursday to our location at the
Thurston County Courthouse.
Please Note
This test is for Coliform bacteria only (including E. coli.). Thurston County also provides nitrate
testing, which is recommended once every three years. If you want your water tested for minerals or
other chemicals, a list of state-certified laboratories is available from Thurston County Environmental
Health and the Washington State Department of Health.
For more information call: Thurston County Public Health & Social Services
Environmental Health Division, 360-867-2673
TDD Line for hearing impaired, 1-800-658-6384
www.co.thurston.wa.us/health/ehdw
Updated (11/30/2022)