The rainy season is about to begin which means the "dirty season" is about to commence for Oakland's cherished landmark, Lake Merritt. The cleanliness of this urban body of water depends in part on the activities of residents of the city--and from November to March, rainwater carries trash from streets to storm drains and into the lake. The Lake Merritt Institute, a non-profit corporation, is dedicated to maintaining the water quality and removing trash from this tidal estuary of the San Francisco Bay. Litterbugs, high-density populations of Canadian geese, and runoff from cars washed in the street are three of the main things things that pollute these brackish waters.

Dr. Richard Bailey, the director of The Lake Merritt Institute is in charge of coordinating the activity that keeps the water sparkling, but its no easy task. Oakland's jewel is on the Environmental Protection Agency's list of Impaired and Threatened Bodies of Water, due in part to high bacteria and low oxygen levels and also due to trash.

As many who enjoy the Lake's beauty know, goose poop is a common problem, littering grass and sidewalks. Large populations of Canadian Geese come to molt, Dr. Bailey said, but they tend to hang out in high-density groups when people feed them human food. More than just unsightly, the excess avian feces is carried into the lake, depleting oxygen levels and raising bacteria levels in the water.

Several years ago the City tried to implement a goose management plan to try to mitigate the problem, but was unsuccessful in pleasing both nearby homeowners and bird lovers. A public opinion poll at the time showed that people were evenly split on whether to leave the geese alone, or manage their large numbers, Dr. Bailey said.

Not to mention, the birds are out of the Institute's purview. Animals are managed by the Nature Center, even though the Lake Merritt Institue is charged with cleaning pollution caused by excess goose poop. However, there are tools that help mitigate this problem. The beautiful fountains around the lake serve a utilitarian purpose--they help to aerate the water, improving oxygen layers and decreasing the "dead zone" layer on the bottom.

Trash is another reason why the estuary is on the list. More than a decade of data shows that the amount of trash collected increases at the same rate as rain level increases. According to an article in The Chronicle, the San Francisco Bay Regional Water Quality Control Board recently mandated local cities must nearly halve the amount of trash in storm water drains, much of which ends up in the Bay and other bodies of water, like the Lake. Bailey refers to the first rain of the season as "The Big Flush," which is how large volumes of garbage end up in the Lake. 

"The big flush builds up all summer and what (trash) doesn’t get picked up by street sweepers, gets carried in at once," he said, referring to an estimated 1,000 styrofoam cups seen floating on the lake after an intense rainstorm on October 19. Responding to a citizen complaint, Bailey explained in an email that some of those foam cups could be seven years old, because they float to the top of storm drains and arent forced in for years at a time. "There are still quite a few [styrofoam cups] from the Glen Echo inlet, but fewer than before ban," he said.

And for those of you who are concerned about pollution flowing inward from the San Francisco Bay, that is not a huge problem, Bailey said. Most likely, bunker fuel from the recent Dubai Star oil spill hasn't made its way into Lake Merrit, due in part to the fact that more water flows out of the lake from runoff than in with the tides from the Bay.

Common trash items are toys, plastic bags, and junk food wrappers. But every now and then volunteers find unusual things like shopping carts, a suitcase, a bird cage, and the occassional message in a bottle. One was a letter to God, one was a recipe and one message inside a frappucino bottle extolled the virtues of Starbucks, Bailey said. There is an entire box of X-rated things too, Bailey added as he packed a box filled with footballs, bouncy balls, wiffle balls, and golf balls into a storage cabinet.

It's not illegal to fish (as long as you have a permit and follow the catch-size rules), but Bailey noted many fish large enough to be caught likely have high levels of heavy metals. Chemicals from automobile tires, copper dust from break linings and other run-off chemicals build up in fish. "Esturaries are like natural sediment traps so they tend to accumilte stuff," Bailey said, adding with a chuckle, "I buy my fish from the market."

Oakland High's environmental accademy does species sampling for educational purposes, but not quite at the research level, Bailey said. But, more than half the acquatic species in the Lake are non-native, thanks to ballast water spewed by ships from around the world at the Port of Oakland. The institute has found species that are native to the Northern Pacific and South America.

Bailey said the lake is definitely cleaner than 20 years ago, even though the Institute has been in place for only 10 years. One positive change has been the disappearance of widgeon grass, which grows in response to high nitrogen levels from feces in the water, dies and then gives off a foul odor. In a 2002 white paper Bailey authored,  this was one main biological concern. In the last five years this species hasn't made an appearance, proably due to three dry years, but could also be related to climate change, he said.

What are the largest challenges Bailey faces in trying to keep Lake Merritt clean? "The biggest problem is ignorance," noting that about half the population doesn't realize trash ends up in storm drains and these drains empty, untreated, into bodies of water such as the Lake.  "Cities are cash strapped and don't have time to cite people for litter," but noted that adding more trash cans and more people to empty them would improve the situation. "The best way is social pressure," urging kids to scowl at litterbugs to make it socially unacceptable.