Sampling is the first and most important step in getting good data!

I have a friend who was a chemistry professor at a local college (he’s retired now), who used to live across the street from me.  One beautiful summer afternoon a while back, taking a break from our yard work, we stood out on the sidewalk chatting about, what else, collecting samples and the analytical process (did I mention we’re both tremendous geeks?).  He commented on how most people have no idea how critical getting a good sample is, and how hard it is in general to get really good data.  The analytical process for almost anything that we test for in the water business has so many steps, each of which compounds any deviations or discrepancies made in the previous steps, that it’s vitally important to be as accurate and precise in each step along the way in order to get good, meaningful data in the end.  And of course that whole process starts with what is the most crucial action of all – taking the sample.  That’s why Title 22 California Code of Regulations, §64415 states that sampling for drinking water systems shall be “performed by a water treatment operator certified by the Department … or by personnel trained to collect samples and/or perform these tests by the Department, a certified laboratory, or a certified operator.”  All of that sampling needs to be done by trained professionals who know what they’re doing.  And it’s not enough to be trained once and then go on your merry way.  Even if you’ve been sampling for years, it pays to refresh your training now and then, because with anyone, errors and missteps can creep into our practices over time without our ever noticing. 

The California-Nevada Section of AWWA has a short book called Water Quality Sampling Guidelines that is getting a bit old, having been published in 2005, but is still a pretty good reference if you have a question or just need a refresher.  The book isn't listed for sale on their web site - http://ca-nv-awwa.org/canv/web/ - but I did call them a while back and they were able to get me a copy for $20.  There are also sampling training references and videos on the web.  A few of them are:

·          The Maryland Department of the Environment sampling video - http://www.mde.state.md.us/programs/Water/Water_Supply/Pages/MCET_DWS_Video.aspx

·          Sampling Drinking Water for Chemical Parameters from NovaTrainingOnline - http://www.youtube.com/watch?v=bZxMuJD0xSo

·          New Mexico Water Sampling Certification Study Guide - http://www.nmenv.state.nm.us/swqb/FOS/Training/WaterSamplingStudyGuide/WaterSamplingStudyGuide.pdf

·          Indiana Water Operator Training Manual - http://www.indianaruralwater.org/IRWA/pages/documents/INDIANA-WATEROPERATORTRAINING-MANUAL.pdf

Your states Rural Water Association; State and County Departments of Public Health; and your local laboratory can also be good sources of information on taking samples.  Sampling is the first and most important step in getting good analytical data about your water system, so be sure to keep your skills fresh and up to date.