How To Take A Water Sample
Irrigation water needs to be tested regularly. Take these steps to ensure your water is top quality.
October 24, 2012
It is important to test your irrigation water on a regular basis, so you know what your water quality is and if any corrective treatments are needed.
When And How Often
It is always a good idea to test your water whenever you start using a new water source. Take another test if there are drastic changes in seasonal water availability due to a drought or high amounts of rainfall. These events can affect your water quality, especially if you are using a well or surface water for irrigating.
Growers that produce year round should plan on testing their water twice a year, once in the winter and once in the summer. Seasonal growers should test their water just before the growing season.
Before you take your water sample, be sure to have a few materials gathered. You will need access to your water source, and a hose attached to a nearby spigot works well. You will also need a large bucket, a bottle to put the sample in, some paper towels, the submission form from your favorite testing laboratory and an envelope to mail the sample.
The water that has been sitting in your irrigation line and hoses may not give an accurate sample for your water test. To ensure you are getting fresh water from your water source, turn your hose on for several minutes to flush the pipes and hoses. The time this takes will depend on how far your hose is from the source of the water. This may take three to five minutes. To take a sample, begin by filling a 5-gallon bucket with water from the hose. Using a large bucket will account for any surges or inconsistencies in the water. It will also give a good representation of the water source.
Samples And Submission Forms
It is important to put the sample of water in a clean, unbreakable, spill-proof bottle that is at least 8 ounces in size. Often, testing laboratories provide this bottle, but you can also use a thoroughly cleaned bottle you have on hand. Remove the cap from the bottle and submerge it completely in the bucket of water.
Allow all the air in the bottle to be replaced by water and cap the bottle while it is still completely submerged. This will eliminate headspace in the bottle, which can cause inaccuracies in the final results.
Most labs will provide you with a submission form. Fill out the necessary portions such as your contact information and any other important information pertaining to your water sample. Give your water sample a label and description. This helps get results quickly and efficiently. It will also be useful for record keeping. Label the bottle clearly to match the submission form to reduce any confusion at the lab. Then, place the bottle and form into an envelope or box and ship the materials using an overnight service.
Brian A. Krug is an Extension assistant professor at the University of New Hampshire Cooperative Extension. E-mail him at email@example.com.