OHA Drinking Water Services
OHA Drinking Water Services
Contact Report Details

PWS ID: OR41 00799
PWS Name: SEASIDE WATER DEPARTMENT
 
Who Was Contacted and Phone: Ben Davis (503) 440-6133
Contact Date: 12/07/2010
Contacted By: SALIS, KARI (DWP)
Contact Method/Location: Office
 
Assistance Type: OTHER REGULATORY - REGULATORY ASSISTANCE
Reasons: SWTR
Chlorine
 
Details: SUMMARY: chlorinator went out - plant shut down DETAILS: Ben called to say that their low-chlorine alarm was triggered early Tuesday morning. At 12:15 am they got an alarm that the chlorine was less than 0.5 ppm. At 12:25 the chlorine residual was 0.23 ppm and the shut-down process began (automatic at less than 0.3 ppm). At 12:31 the chlorine residual was 0.19 ppm just before the plant actuallly shut down. Readings are recorded every 6 minutes. Ben was worried that some water, maybe a minute and a half, went into the clearwell at less than 0.2 ppm. I told him 0.19 would be considered 0.2 and not to worry, as long as CTs are met. He later calculated that, and with 231 minutes of contact time and a CT required of 35, CTs were met even at this time. ACTION NEEDED: No violation, no action needed. Ben will consider setting the alarm to shut off at 0.4 or 0.5 to prevent this from happening in the future.