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 | ||
Contact Date: | 12/05/2020 | ||
Contacted By: | CIVIL WEST ENGINEERS, INC (DWP) | ||
Contact Method/Location: | Field | ||
Assistance Type: | CIRCUIT RIDER ASSISTANCE | ||
Details: | E. Hofeld of OHA reached out to the circuit rider to provide emergency support to the City of Gates in anticipation of water quality issues due to recent widespread fires in their watershed. There were several support issues the circuit rider was asked to address: • Identify feasibility of auto-dial alarm for raw water NTU meter (HACH Surface Scatter 7) – currently no alarms or automation for raw water turbidity. • Identify potential to install coagulation (identify feasibility issues and appropriate injection site) • Quick jar test demonstration – circuit rider needs to bring their own coagulant (polyaluminum chloride (PACL) or ACH (preferable) – polymers cannot be used on membranes. Water system has jar testing equipment on-site but has never used it. • Estimate costs for raw water auto-dial and/or automation and piping/static mixer/coagulation and related controls – all coagulation considerations need to be run by membrane manufacturer. Assistance Provided: The circuit rider has visited the site and assessed the needs of the system with the operator. The circuit rider worked with TAG to determine a scope for the cost/feasibility of integrating the raw water turbidity meter with SCADA and the existing WIN-911 auto dialer. Circuit Rider maintained contact with Greg post-fire/rain events to monitor possible “flashiness” of the surface water source due to anticipated run-off. Greg noted slightlty higher turbidity events approaching 30 NTU, but felt it was manageable without resorting to integration of the raw turbidity meter with the plant operations. Follow-Up Actions Needed: The circuit rider will maintain contact with G. Benthin on the remaining tasks as he is able to address them. The city lost a considerable number of rate payers due to the fires and is burdened budget-wise. |