Testing: Water

Water Test Results - June 29, 2010 Sample

I took samples from Lett's Creek on the evening of June 29th and they were delivered to National Testing Lab's Ypsilanti lab location on the morning of June 30th.    The samples were collected from the creek at the spot where we usually draw up water in buckets, and where the new pump system will have its intake.   At the time of sampling, it had not rained recently, so this was a low-flow situation.

The results arrived this week, and you can download them below.   In my opinion, they are very good.

- Tom


Bacteria: Coliform bacteria and E. coli bacteria were both present.
This is not surprising since this is a creek, not drinking water.  The test was for presence/absence, so no counts or other measures are available.    Since many of us fertilize with manure, the presence of E. coli around the garden is to be expected.  

Basic rules should apply when using creek water on your vegetable garden:
  • Don't drink the water.  It is for irrigation only.
  • Wash your crops well before eating, storing, or using for meal preparation.
  • If you are immune-suppressed or in any way at special risk from bacteria, take necessary precautions or avoid the garden site altogether.
Other Items
  • No pesticides were detected. 
  • No other contaminants were detected above the level of a standard requiring special action or concern.
  • The creek water is hard, slightly alkaline, and has quite a bit of dissolved solids in it.
Substances that were detected at measurable levels included
  • Calcium
  • Iron
  • Magnesium
  • Manganese
  • Potassium
  • Silica
  • Sodium
  • Chloride
  • Sulfate
Some of these are minerals we need, and none of them were found at substantial levels. See attached document at bottom for full results.

Summary and Next Steps

As long as we are all aware of the bacteria and act appropriately, the water from Lett's Creek looks very suitable for irrigation.

We have another test kit, and we will draw another set of samples later in the summer just after a significant rainfall, so that we can get measurements at a high-flow condition.  

Stay tuned for the next set of results, and in the meantime, please share these results with everybody who might want to know about watering at the Chelsea Community Garden from Lett's Creek.

Questions, comments, or anything we should talk about as a group?  Post to the list and let's get the conversation going.

Other Information

For those who want to know, we chose the 'Water Check with Pesticide Option' for our test, which is pretty comprehensive.   The company site is


and the Water Check service and options are described here: