BY DEBORAH SULLIVAN BRENNAN
Originally published in the San Diego Union-Tribune on June 21, 2013
Bacterial odor eaters are cleaning the La Jolla cliffs, aiming to banish the bird poop stench that has plagued the coastal town.
Starting last week environmental contractors applied a foamy mixture of bacillus bacteria – a kind of microbial Scrubbing Bubbles – to the guano buildup at the picturesque cove.
“They’re getting it on fairly thick,” said Bill Harris, a spokesman for the San Diego Parks and Recreation Department. “At least anecdotally, the first day did make an impact on the smell.”
Sheila Fortune, executive director of the La Jolla Village Merchants Association, said her assistant, who had just run an errand at the cove Friday afternoon, reported major progress.
“She said it is much better,” Fortune said. “She said she really couldn’t smell anything today. So that is a great improvement.”
Fortune said the treatment is a welcome step toward resolving the problem.
“We’re definitely relieved. It’s very important that our tourists and our business owners have pleasant experiences when they travel here. Hopefully this is going to be the beginning of a nice fix for everyone.”
Patrick Ahern, a La Jolla realtor and board member of La Jolla Parks and Beaches, said the absence of odor is evidence of success.
“We’re noticing an improvement by noticing nothing,” he said.
The city had grappled with accumulated droppings from gulls and cormorants since last fall, when the foul smell drew national headlines and local outrage. City officials received dozens of pitches for products and procedures aimed at solving the problem, correspondence showed, and considered myriad ways to stem the stench.
City staff fielded pitches from producers of other biologically based cleaners, as well as proposals to power-wash the cliffs from fire-boats, haze the birds with trained falcons, or install tarps or spikes to deter the roosting animals. But they faced limits from regulators, who warned that the solution could not disrupt wildlife or send runoff to the ocean.
Last month the city settled on Blue Eagle, a San Rafael-based firm that uses a mix of bacillus bacteria to consume the bird droppings. The company has supplied similar odor eating solutions to the city of Sacramento and the Colorado Springs Zoo.
Their products employ microbes to digest waste including sewage, garbage odor, commercial kitchen grease and even petroleum spills, said CEO Robert Ahern.
The bacteria are selected for safety and effectiveness, and digest the bird droppings through the Krebs cycle, by which organisms generate energy by breaking down food and releasing carbon dioxide and water
The microbes out-compete other strains that release foul-smelling methane or hydrogen sulfide, quickly cutting the odor, Ahern said. Eventually they digest the bird droppings and then die off naturally.
On May 29, the company treated a test patch of the cliffs, and then returned to the lab to fine-tune the formulation. Blue Eagle adjusted the solution to the right viscosity, adding foaming agents and removed its signature blue dye to avoid staining the rocks, Harris said.
Last week they began treating the cliffs, starting with a ledge opposite the restaurant Brockton Villa. Contractors started before dawn and wrapped up by noon to avoid peak tourism hours, steering clear of nesting gulls.
“They got rigged up, got hoses ready, began applying the product under the watchful eye of the monitoring biologist, who was eagle-eyed,” Harris said.
Harris said the treatment will continue on weekday mornings until the end of the month. Contractors will make a second pass in late July, he said, when nesting season is over. The cost of the two treatments is just under $50,000, and city officials said last month that they will need to repeat the treatment a couple times a year to keep the odor at bay.
In the meantime La Jollans are breathing a sigh of relief.
“We are hopeful that this is the beginning of a long-term plan to keep the cove clean so its beauty can be experienced and enjoyed by locals and tourists year-round,” Dave and Megan Heine, owners of the La Jolla restaurant Brockton Villa, said in a statement.