CITY OF DALLAS WATER UTILITIES (DWU)
	Plant Control System Upgrade
	Dallas Water Utilities provides water and wastewater services to about 1.9 million people in the greater metropolitan area of the City of Dallas, Texas.

Issue
DWU is continually striving to maintain and upgrade their plants, equipment, and processes to support system expansion, more stringent treatment requirements and lowered operation and maintenance costs.

Solution
Westin executed a structured Needs Assessment to document and develop a business case for a control system (SCADA) replacement at DWU’s Southside Wastewater Treatment Plant (WWTP). Based on the findings of the Needs Assessment, Westin developed a Plant Automation Plan that identified projects critical to accomplishing DWU’s goals and objectives of automation at the WWTP including:

• Strengths and weaknesses of the existing plant control system and process instrumentation
• Appropriate level of automation by process area
• Improvements essential to achieve desired automation goals.

The Plant Automation Plan process included existing documentation reviews, on-site investigations, and a number of workshops with plant personnel and engineering staff. Workshop topics included:

• Current methods for controlling plant processes (best practices)
• Types and quantity of field instrumentation, including missing instrumentation and/or unreliable instruments (fit/gap analysis)
• Recommendations for essential upgrades and capacity expansion
• Ongoing and upcoming process improvement projects that will affect the plant control system.

Outcome
With the Plant Automation Plan as a guide, DWU made structured and rational investments in plant and infrastructure to support the wastewater treatment needs for a growing population. A PCS upgrade project is underway which includes a new Human/Machine Interface (HMI) System, a plant-wide fiber optic network, and state-of-the-art Programmable Logic Controllers. In addition, advanced control strategies are being implemented to achieve cost savings in several key process areas including chemical and energy management.