OHA Drinking Water Services
OHA Drinking Water Services
Contact Report Details

PWS ID: OR41 00611
Who Was Contacted: Civil West
Contact Phone: 541-219-0841
Contact Date: 02/05/2018
Contacted By: WRAY, JULIE (DWP)
Contact Method/Location: Phone
Details: Chris researched system specifications and plans. Using media data correlated to the system physical constraints the following has been deduced.

The slow rise in arsenic levels has been due to ineffective backwashing parameters. Duane told Chris over the phone that the backwash flow rate he has been using is between 85-95 gpm. After looking through the media specifications and correlating the media to the physical constraints of the system, the range for effective backwash flow per this specific system is 101-130 gpm. Not reaching these flow rates lowers the efficiency of the treatment system. I also know that they have had backwash blow outs in the past and that was one of the reasons why they lowered the backwash flow rate. It is crucial to optimize the backwash flow rate to maximize arsenic removal and increase efficiency but not blow out the media in the process.

Call system operators in a couple of weeks to see if system performance has increased.

For further information on this public water system, click on the area of interest below:
System Info :: Report for Lenders :: Alerts :: Violations :: Compliance & Enforcement :: Contacts & Advisories :: Site Visits :: Public Notice
Coliform Summary :: Coliform Results :: Sampling Schedule for Coliform :: Groundwater/GWUDI Source Details :: Plan Review :: Annual Fee
Chemical Group Summary :: Latest Chemical Results :: Entry Point Detects :: Single Analyte Results 
Chemical Schedule Summary :: Chemical Schedule Details
Lead & Copper :: Corrosion Control (LCR) :: Nitrate :: Arsenic :: Radionuclides :: GWR 4-Log :: LT2 :: Cyanotoxins
DBPs :: TOC & Alkalinity :: DBP Sample Sites :: FANLs :: MRDL :: Turbidity :: SWTR :: RAA :: LRAA For SDWIS: 3770