REPORT TO THE CITY COUNCIL
January 12, 2017
FROM: THOMAS C. ESQUEDA, Director
Department of Public Utilities
BY: MICHAEL CARBAJAL, Planning Manager
Department of Public Utilities - Water Division
SUBJECT
Title
***Resolution - 31st amendment to the Annual Appropriations Resolution 2016-118 to appropriate $500,000 for the installation of a permanent calcium hydroxide chemical feed system at the Northeast Surface Water Treatment Facility. (Requires 5 affirmative votes)
Body
RECOMMENDATIONS
Staff recommends that the City Council adopt the 31st amendment to the Annual Appropriations Resolution (AAR) 2016-118 to appropriate $500,000 for the installation of a calcium hydroxide chemical (Ca(OH)2) feed system at the Northeast Surface Water Treatment Facility (NESWTF).
EXECUTIVE SUMMARY
The Department of Public Utilities (DPU) is recommending that the City Council appropriate $500,000 within the DBCP Recovery Fund. The appropriation is necessary to fund the design, purchase of equipment, permits, and construction necessary to install a Ca(OH)2 chemical feed system at the NESWTF. DPU staff has determined that calcium hydroxide has beneficial features and characteristics for alkalinity adjustment, pH adjustment, and calcium addition for finished water produced at the NESWTF.
BACKGROUND
The City has previously conducted water treatment trials using calcium hydroxide for alkalinity adjustment, pH adjustment, and calcium addition at the NESWTF. During the previous water treatment trials, operational challenges were encountered with the use of calcium hydroxide. During calendar year 2016, DPU conducted additional treatment trials using calcium hydroxide, and implemented mitigation measures to address the previously encountered challenges. The mitigation measures implemented by DPU during calendar year 2016 proved successful, and DPU proposes to construct a permanent calcium hydroxide feed system at the NE SWTF.
The permanent calcium hydroxide fee...
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