How Glendale Sewage Turns Downtown’s Newest Park Green

Los Angeles State Historic Park is nearing its opening in January. The final task is to literally grow the grass. 

DTLA - After two and a half years of work, the $20 million Los Angeles State Historic Park is nearly ready to open. That’s clear to anyone who drives by and sees the green grass sprouting where once beige dirt proliferated.

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The property stretches along Spring Street in Chinatown, comprising 32 acres of undulating, picturesque landscape. The delay-plagued project is creating new amenities, including a visitor’s center, and attractions such as a pedestrian bridge offering sweeping views. A wetlands area will anchor the north end of the park.

For now, however, the gates remain locked. The reason is simple: The California Department of State Parks is literally waiting for the grass to grow. 

Ensuring that happens amid a historic drought is no easy task.

Many parks, golf courses and other large green spaces have dedicated pipelines for their irrigation systems. That’s not the case here.

If you have seen a tanker truck slowly rumbling onto the park site over the past several months, there’s a good chance that it was filled with water. The State Parks department has been using three trucks to deliver approximately 16 loads a day, every day. It amounts to 60,000-80,000 gallons daily, and it is pumped into storage tanks that feed the irrigation system. 

All that water is still only enough for eight acres, specifically the large expanse of turf at the heart of the property. A second phase of watering through the autumn will feed native plant meadows around the edges of the park.

“The turf and plants can’t be transplanted, they need to be established on site,” said Brian Dewey, State Parks assistant director for acquisition and development. “We’re bringing in water, but the key is that because we’re in an emergency drought situation, we can only use reclaimed water.”

The trucks shuttle back and forth between the park and a pumping station about a mile away. The real source, however, lies seven miles away in Glendale. 

Tucked into an industrial block on the east bank of the Los Angeles River, just across from Griffith Park, is the L.A.-Glendale Water Reclamation Facility. Reclaimed water is basically water that has been recycled out of raw sewage using a series of filtering processes. It’s not drinkable, but it is a critical resource for uses such as irrigating golf courses or filling toilets.

The L.A.-Glendale plant was the first reclamation site for Los Angeles when it opened in 1976. Today it processes approximately 17 million gallons of sewage a day, resulting in a daily average of 5.5 million gallons of recycled water. Another 8.7 million gallons of treated water is dumped back into the Los Angeles River to keep it flowing.

“We put that sewage through primary treatment, which filters out a lot of solids and particulates, then a secondary biological treatment that reduces the nutrient content,” said Michael Ruiz, operations superintendent of the city Dept. of Sanitation’s water reclamation division. “There’s a tertiary filtering process to make it usable. Altogether, it removes ammonia, heavy metals and pathogens that would kill plants.” 

The trucks won’t shuttle water indefinitely. State Parks is building a temporary pipeline to divert water from the widening of the nearby North Spring Street Bridge. The six-inch-diameter steel pipe will run south through the bridge site, then underground and west along Aurora Street to the northeast corner of the park.

Once the bridge is completed, the water main will be extended to feed the park permanently. The cooler weather and expected rains should taper off irrigation amounts in the next month or two, Dewey added.

The park itself was designed with water conservation in mind; in addition to drought-resistant plants, it features an underground cistern, bioswales (or landscaping elements that collect and naturally filter runoff water), and permeable paving on the parking lots, all with the purpose of harvesting rain water.

Using it efficiently is a task suited for computer programs. “The irrigation equipment itself utilizes rain and moisture sensors that are cutting edge and can track water very precisely,” Dewey said.

For now, the waiting and watering continue. L.A. State Historic Park is already looking quite sharp, and it has the sewage of Glendale and the East San Fernando Valley to thank for it.

© Los Angeles Downtown News 2016