OHA Drinking Water Services
Contact Report Details |
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PWS ID: | OR41 00317 | ||
PWS Name: | GATES, CITY OF | ||
Who Was Contacted: | Greg Benthin | ||
Contact Phone: | 503-897-2669 ext 5038972669 (Email address hidden) | ||
Contact Date: | 06/03/2020 | ||
Contacted By: | BAIRD, GREGG (DWP) | ||
Contact Method/Location: | |||
Assistance Type: | OTHER WATER QUALITY - Watershed saxitoxin gene detection | ||
Reasons: | Cyanotoxins |
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Details: | DEQ has been working with the City of Salem and EPA to do qPCR monitoring for detection of genes from cyanotoxin-producing cyanobacteria in Detroit Lake. Last week’s sample in the area of the lake called Log Boom revealed a level of saxitoxin gene copies that suggest the toxin might be present. OHA’s procedure for gene detections is to ask the nearest downstream public water facility to test for the corresponding toxin. The City of Gates is the first downstream water system, so at OHA's request, DEQ is sending them a few monitoring kits with bottles specifically for saxitoxin monitoring. We have asked Gates to collect both a raw and finished water sample this week, freeze them, and ship on Monday. The raw sample will be analyzed for saxitoxin and if present, the finished water sample will also be analyzed. Update 6/19/20: the raw sample was collected 6/8 and was non-detect for saxitoxin. A sample collected from Detroit Lake on 6/5 was also non-detect for saxitoxin. Gates collected another set of samples (both a raw and finished water sample) yesterday 6/18, and will freeze and ship on Monday. The raw sample will be analyzed for saxitoxin. The finished water sample will only be analyzed if saxitoxin detected in the raw. If still no detections (and in the absence of other information such as gene or toxin data from the lake), no further saxitoxin monitoring will be conducted. Update 6/26/20 final results received from DEQ lab for sample collected 6/8. Both raw and finished samples were analyzed. Both were non-detect for saxitoxin, although both the matrix spike and matrix spike duplicate had lower than acceptable recoveries, which DEQ attributes to the standard stock (not the sample matrix or prep). The 6/18 sample will be analyzed as soon as new standard stock is obtained. |