Foresight is 20/20

Burbank Water and Power has pursued a path of conservation, recycling and judicious pipe replacement to build an enviably efficient system.
Foresight is 20/20
The “green roof” of the Burbank Water and Power building absorbs and disperses heat more efficiently than a traditional roof and saves in energy costs.

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California's Burbank Water and Power (BWP) boasts a successful water conservation program, an ambitious recycled water program, a system leakage rate of less than 3 percent, and a state-of-the-art, environmentally friendly head office dubbed the EcoCampus (see sidebar).

Team effort has transformed the utility, which, a little over a dozen years ago, was experiencing decreasing reliability in its water infrastructure.

"Stakeholders were beginning to question the value of their municipally owned utility and the utility was becoming concerned about the value it was bringing to the community," says Joe Flores, marketing associate and conservation manager with BWP. "In 1999, our current general manager, Ron Davis, joined BWP and started to develop a master plan for our infrastructure. He also kick-started restoration of the utility's value to customers through the three pillars of reliability, affordability and sustainability."

As part of its management framework, BWP began to develop explicit objectives specific to environment, finance, leadership, operations, organization and water management. These goals, strategies and explicit performance measures are included in the city's annual budget.

Making water do more

About 49 percent of Burbank's water is purchased directly from the Metropolitan Water District of Southern California, of which the city was one of 13 founding members. About 42 percent is groundwater drawn from the San Fernando Basin. The rest is recycled water produced by the Burbank Water Reclamation Plant.

"However, no matter how the numbers are divided up, it's all considered imported water," says Flores. "Even pumped groundwater and recycled water begin as imported water."

Burbank operates groundwater wells and a treatment plant, the Burbank Operable Unit, to pump and treat groundwater contaminated with volatile organic chemicals. However, even treated water must be blended with imported water before it's pumped into the potable water system.

BWP's goal, then, is to make its imported water do more — through aggressive leak control, conservation and recycling.

The potable water distribution system consists of about 280 miles of pipeline ranging from 2 to 30 inches in diameter. About 10 percent are transmission mains 12 inches in diameter or larger. The oldest pipes have been in the ground for 90 years.

Enviable leakage rate

BWP's recently completed Water Distribution System Master Plan revealed that the system is in remarkably good shape. A study of leak data collected from 1953 to 2010 shows that the system experiences an average of seven leaks annually per 100 miles of pipeline, well below the national average of 24.

"What's noticeable is that, on average, the leak rate has been almost stable since 1953," says Bassil Nahhas, principal civil engineer responsible for the potable water distribution system with BWP. One of the reasons for the low rate is that the utility has consistently specified quality materials and designed its pipeline systems using heavier-walled pipes exceeding the commonly used safety factor of 2.0. The utility also required double cement lining inside ductile iron pipes. "These additional features help the distribution network to better resist the effect of corrosion. And for that, you can credit senior management and City Council when it comes to budget time," Nahhas says.

The utility fields a water main construction crew made up of eight workers who install waterlines up to 18 inches in diameter. Nahhas credits them for their conscientious work. "In-house construction crews tend to have a sense of ownership of their work," he says. "Our crews pride themselves on doing quality work."

Almost 80 percent of the pipes are cast iron and these demonstrate an even lower incidence of leaks, about three per year, as compared to a national average of 30.

"The pH and resistivity of our sandy soil are two good proxies to assess soil corrosiveness. The majority of the soil in Burbank is simply favorable to iron pipes," he says. "Additionally, the groundwater is chemically stable, at a consistent pH of about 7.8, which makes our water less aggressive."

The weak links in the system are 16 miles of smaller-diameter galvanized steel and cast iron pipes 4 inches or smaller. Most breaks occur in winter months, due to contraction of pipes when colder water enters them.

Prior to the new master plan, pipe replacement was conducted on pipes that were substandard in size or material, pipes in streets scheduled for resurfacing, and upgrades and replacements necessary to support development. Under the new master plan, pipes are slated for replacement are based on their existing conditions and recent performance, and are placed into one of three categories. Category 1 indicates replacement in less than five years. Category 2 indicates replacement from five to 15 years. Category 3 indicates replacement from 15 to 25 years.

"To replace a pipe solely according to age doesn't make sense," says Nahhas. "We only replace pipes based on actual condition assessment, and after conducting an economic analysis to determine a cost-benefit ratio — there's no point in a proactive replacement if it doesn't add value to the community. Many utilities struggle with finding the sweet spot where replacement provides the maximum reliability at the lowest possible cost. This utility has found it."

BWP has prioritized 32 miles of pipeline for replacement in the next 25 years at an estimated cost of almost $35 million with an average replacement rate of 1.3 miles per year. Utility officials expect this consistent and judicious renewal approach will enable the utility to continue to provide a reliable water service at the lowest possible life cycle cost.

BWP also conducts an annual valve maintenance and replacement program. Deficient valves are either tagged for repair or replacement. Failing distribution system valves 12 inches and smaller are typically replaced — they're usually irreparable — while large transmission system valves are repaired to extend the useful life of transmission mains. BWP plans to replace all transmission valves older than 70 years in the next five years at a rate of five valves per year. "Replacing only the deteriorated valves and avoiding the costly replacement of the whole pipe is a very cost-effective technique that should double the useful life of the transmission pipe," Nahhas says.

New efficiencies

A conversion to smart meters from 2009 to 2011 saw some water meters upgraded, and the utility's existing Neptune water meters married to Itron transmitters. This helped to reduce unbilled water losses.

"Some older mechanical meters were not reading 100 percent of consumption," says Flores. "Also, if we now see that a customer has consumption 24 hours a day, we ask 'Is that normal for you?' If it isn't, there's likely a leak somewhere."

A reservoir replacement project is further increasing system efficiency.

"The original reservoir built in 1928 was basically a concrete-lined dam built against a vertical rock face and covered with a wooden roof," says Michael Thompson, principal civil engineer with BWP, responsible for groundwater treatment. "It had been leaking and costly to maintain, so we're replacing it with a modern reinforced concrete design with a concrete roof."

The old reservoir offered a 6.9-million-gallon capacity. The new one will offer a 9.5-million-gallon capacity on the same footprint by excavating 5 feet deeper. Backup reservoir capability will serve customers during the two-year construction schedule.

"Taking that leaking reservoir offline probably saved us as much as 1 percent in leakage," says Flores. "That took us down those last few points, so that we're now down to 2 to 3 percent overall system leakage."

Recycled water expansion

Recycled water also helps to reduce dependency on imported water.

BWP has been using recycled water since 1967, when it started using the water in its power plant cooling towers. The system gradually expanded to serve all the major irrigation customers within the city.

"The system has seen rapid expansion over the past three years with a $17.5 million project to add 100,000 feet of pipe to recycled lines," says Matthew Elsner, principal civil engineer responsible for recycled water. Today, Burbank's recycled system includes over 27 miles of dedicated pipelines.

Burbank City Council policy requires larger water customers such as golf courses or major film studios to use recycled water. The city has also extended its recycled water system to serve customers in Los Angeles.

"By exporting recycled water to Los Angeles, we can exchange for groundwater credits that allow us to pump an equal amount of groundwater from the San Fernando Basin," Elsner says. "Recycled water is a very attractive proposition for us. We expect to deliver more than 1 billion gallons of recycled water in 2013, with an eventual goal of supplying 15 percent of Burbank's water supply."

Under the state's Water Conservation Act of 2009, all utilities will need to ensure that their customers use 20 percent less water per capita by the end of 2020 than in 2008. Burbank customers used an average of 195 gallons of water per day in 2008, and have already achieved the goal of the legislation by reducing usage to 149 gallons per day, better than its 155-gallon target.

While customers have largely maintained that level of performance, the numbers have briefly crept back above the limit on a few occasions.

"We're well ahead of schedule, but the trick will be to stay below 155 gallons per day over the next few years," says Flores. "But watching reports on those numbers has demonstrated to our customers that simple actions taken by each of them can dramatically reduce water use. Every step we take as a utility, and as customers, can help us to move closer to the goal of becoming a more sustainable water utility."

Burbank Water and Power’s EcoCampus a Model of Sustainability

It’s not often that a utility can demonstrate the sustainable landscape technologies it promotes to its customers at its own head office.

Burbank Water and Power (BWP), working with Los Angeles-based AHBE Landscape Architects, transformed its 23-acre main site into “The EcoCampus,” a green space that integrates multiple sustainable technologies on one property.

“One feature is our Green Street that demonstrates five stormwater capture technologies over a full three city blocks,” says Michael Thompson, principal civil engineer with BWP and project manager for the campus’ Green Street feature. “One of its goals is to produce zero runoff of stormwater.”
In addition to demonstrations of sustainable power, the campus features:

  • The Green Street renovation project, which showcases five stormwater management systems: permeable pavers and a gravel reservoir designed to supply water to underground cells filled with planting soil to accommodate tree roots; the Silva Cell System, which creates an underground framework to support tree root growth; the Kristar Tree Pod System, which filters out pollutants found in stormwater runoff; infiltration planter bump-outs, featuring plants that thrive during both stormwater flows and summer droughts; and filtration planters, which use planter soil to remove pollutants from stormwater runoff before it infiltrates into the ground.
  • Demolition of an unused substation, which has transformed BWP’s Centennial Courtyard into sustainable landscaping. Courtyard stormwater is directed to an old utility tunnel that now uses plant species to filter runoff.
  • Renovation of the historic BWP administration building, designed to achieve a LEED Platinum rating from the U.S. Green Building Council. Three rooftop gardens use plants to absorb more than 70 percent of rainwater that falls on the building. Two underground storage and percolation tanks capture overflow for infiltration.

“The EcoCampus isn’t something that just happened in one flash,” says Joe Flores, conservation manager with BWP. “It took over a decade to develop as we learned new ways of doing things. It’s now something that our customers can learn from by seeing these technologies in action.”


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