OHA Drinking Water Services
Contact Report Details |
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PWS ID: | OR41 00657 | ||
PWS Name: | PORTLAND WATER BUREAU | ||
Who Was Contacted and Phone: | Yone Akagi (503) 823-7648 | ||
Contact Date: | 04/20/2010 | ||
Contacted By: | SALIS, KARI (DWP) | ||
Contact Method/Location: | Office | ||
Assistance Type: | WATER QUALITY ALERT RESPONSE | ||
Reasons: | Coliform N/A |
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Details: | SUMMARY: Ecoli + response - open reservoir DETAILS: While at a Risk Communication seminar, Chris Wanner informed me that a routine coliform sample taken from the outlet of uncovered Reservoir 1 on Mt Tabor, showed a presence of Ecoli. The sample was taken Monday morning, 4/19, with a total chlorine residual of 1.4 ppm. As per their new protocol, a downstream sample had been taken at the same time, and it was negative for total coliform. Tuesday morning, routine samples were again taken from the reservoir outlet and the same downstream sample site. Results from Monday’s test came back today around 11:30 am. The reservoir was then taken off-line as per their new protocol, to reduce possible exposure. We discussed repeat sampling. Rather than do an upstream location (since it is different water quality), we talked about using modeling results to determine where the Res 1 water went, and take repeat sample from that area. Later it was determined that the Res 1 water went down Division and into downtown. They do not have sample stations in that area, so 4 samples were collected from Benson bubblers, and 1 from a regulating valve. A sample was also taken upstream of Res 1, as well as an additional repeat sample at another downstream location from Res 1, though the water likely does not represent water that came from Res 1. Portland staff are beginning to work on notification in the event that a boil water advisory is necessary. ACTION NEEDED: 4/21 all re-samples came back absent for coliform. No further action needed at this time. Yone and I will talk about how their sampling plan could be improved. | ||
Associated Alerts: | COLI7544 - 04/20/2010 - COLIFORM (TCR) , E. COLI COLI7544 - 04/20/2010 - COLIFORM (TCR) , E. COLI |