Creating a Culture

Portland Water Bureau reduces costs and greenhouse gas emissions through electrical efficiencies and a smart fleet management program.
Creating a Culture
One of Portland Water Bureau’s Toyota Prius hybrid vehicles.

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The City of Portland is well known for its environmentally minded citizens and government. This sustainable culture extends to the city’s water bureau, which has been steadily reducing use of electricity and vehicle fuel and installing more solar energy arrays. The improvements mean big cost savings and lower greenhouse gas emissions.

With a staff of 600, the bureau serves 935,000 people in Portland and 19 wholesale-buying communities in Multnomah, Clackamas and Washington counties. The fiscal year 2012-2013 budget is $219 million. The primary water source is the 102-square mile Bull Run Watershed in the Mount Hood National Forest, federally protected land managed strictly for drinking water and hydropower production. The pristine waters enable Portland to bypass filtration.

The water is gravity-fed through 22 miles of pipeline to the city. At the Bull Run Headworks treatment plant, chlorine is added. The water travels five miles to the Lusted Hill treatment plant, allowing time for chlorine absorption. Then ammonia and sodium hydroxide are added to sustain the chlorine level and adjust the pH.

Six reservoirs and 62 storage tanks hold three days’ supply of water; 30 pump stations deliver water to customers. The system delivers an average of 100 mgd. When the watershed has high turbidity or during high water demand, Portland uses a secondary groundwater source of 27 wells that can produce up to 102 mgd.

Energy charter

In February 2010, the bureau adopted an energy management charter that set goals for energy efficiency and renewables. Having all department directors on board was key to setting things in motion. “There was a high level of buy-in from decision makers on energy management,” says Kavita Heyn, sustainability coordinator. “We developed a culture of energy awareness to encourage efficiency, promote renewable projects and establish a baseline to track and evaluate energy use.”

Staff from resource protection, engineering and operations came together to identify efficiency improvements (especially at pump stations), seek financial incentives to implement and track projects.

Portland has cut energy consumption by using its pumps more effectively. Since 2005, operators have been analyzing pump efficiency in the seven largest pump stations, which offer the greatest potential for energy savings. They use baseline data from the SCADA system to determine how long the pumps run and how much water they move.

In stations where there are redundant pumps, the most efficient pumps are used most of the time and are set to fill the tanks during off-peak hours when electricity is least expensive. Besides using information from the SCADA system, operators manually read pump gauges and fine-tune valves, yielding more efficiency.

“Originally our system used altitude valves because the pump stations would pump directly into distribution lines,” says Mia Sabanovic, engineering associate. “Now that we pump into the tanks, the valves have been dialed down, which cuts energy waste. We gained efficiency by doing field inspections.” In the colder months, operators close louver vents and lower thermostat settings in the pump stations. More efficient pump operations saved 1.5 million kWh in 2010.

Building efficiencies

In 2010, the bureau updated its 15,000-square-foot meter testing shop to LEED Gold certification by adding energy- and water-saving features. A water recycling system allows reuse of half the water used for meter testing. A 12.24 kW roof-mounted solar photovoltaic array replaces 10 to 25 percent of the building’s utility power and has saved an estimated $3,030 in energy costs.

A solar thermal system provides all necessary hot water for half the year. An energy recovery ventilation system captures 75 percent of the heat from exhausted air before it leaves the building. Sensors automatically adjust interior lighting when sunlight is present.

The meter shop renovation cost $3.26 million, paid with help from a $30,000 incentive from the Energy Trust of Oregon. The bureau plans to incorporate energy- and water-saving features into two new LEED Gold certified staff buildings under construction. 

Besides the solar array at the meter station, the bureau has a 9.8 kW roof-mounted array on the groundwater treatment station that has saved an estimated $749 and six tons of CO2 to date. A 267 kW array at the groundwater pump station includes 1,274 Kyocera solar panels that annually produce almost 300,000 kWh. When the groundwater pumps are operating, the array can fulfill 5 percent of the pump station’s energy need. The array was installed under a seven-year agreement with Groundwater Solar, which paid most of the $2.1 million cost in exchange for revenue from power sold to the grid.

Fleet management

To reduce fuel consumption in its 400 passenger and construction vehicles, the bureau has an extensive fleet management program. A database tracks each vehicle’s fuel use, miles per gallon and total mileage. “We can see if a vehicle is as efficient as it should be and allocate vehicles with lower miles per gallon to staff members who drive fewer miles,” Heyn says. “We also use engine coolant heaters in 40 of our trucks so they don’t idle to warm up on cold winter days.”

Most vehicles use a biodiesel blend that emits fewer particulates, reduces engine wear and cuts greenhouse gas emissions. Between 2007 and 2011, the bureau reduced its gasoline and diesel use by 16 percent, saving 7 percent of CO2 emissions annually.

Overall, the bureau has built a culture of sustainability by educating staff on the benefits of the efficiency and encouraging participation at every level. “We’ve empowered employees so anyone can share good ideas on how to improve operations,” Sabanovic says. “We share the results of our improvements and include the staff, right down to the operators who installed the pumps. Every operator wants to be the one saving money for the organization.”



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