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The City of Portland's Columbia Boulevard Treatment Plant is undergoing a 40 million wet weather treatment expansion that increases the plant capacity and to add additional primary treatment and wet weather processes and extensive renovation of the existing primary treatment facilities. Final plant design was completed in 1996 with construction to be phased over 5 years. The processes included:

New dry weather primary treatments

Convert the existing primary treatment to wet weather primary treatment

Upgrade the chlorination system to a separate wet weather and dry weather chlorination systems

Dechlorination system

New effluent pump station

Outfall control system

Digester pump station

The operational objective is to operate the additional treatment processes without adding any O&M staff. The control system objective is to provide sensible automation to achieve the operational objectives. The new wet weather process is designed to control excess flow to the dry weather clarifiers by diverting to the wet weather clarifiers. The control system then automatically fills the wet weather clarifiers, bringing them online, automatically starting wet weather chlorination, and wet weather dechlorination. When the wet weather event is over the wet weather clarifiers, contents are fed back into the dry weather system and the clarifiers are automatically flushed and made ready for the next wet weather event. This type of control places a burden on the control system configuration, operation, and maintenance.

Key to the success of the control system and SCADA system is to provide timely and appropriate information to the Operational and Maintenance staff.

Document Type: Research Article


Publication date: January 1, 2000

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  • Proceedings of the Water Environment Federation is an archive of papers published in the proceedings of the annual Water Environment Federation® Technical Exhibition and Conference (WEFTEC® ) and specialty conferences held since the year 2000. These proceedings are not peer reviewed.

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