Perils of the first flush

The unusually pungent aromas blanketing O.B.'s Dog Beach and Mission Bay on a Tuesday morning are enough to tell even the most casual observer that something's not right.

Indeed, these two popular coastal destinations are among those listed as the ten worst areas in which the effects of urban runoff can be observed within the county by water watchdog San Diego Coastkeeper.

"We wanted to create a list that includes a full range of runoff problems that we have in San Diego," explains Coastkeeper water-quality lab manager Travis Pritchard. "It's everything from rivers that cross international boundaries to infrastructure that pumps storm water straight to the ocean to highlight creative ways of cleaning up that water before it has a negative impact on greater water bodies."

He has penned a warning regarding the "first flush," a situation faced by locals several times per year when heavy rain following dry periods forces an exceptional amount of pollution into storm drains in a short period of time.

"Depending on the level of swelling you can see tires rolling down the river, you can see garbage…there's all sorts of sewage impacts there," Pritchard says of flows from the Tijuana River, which tops Coastkeeper's list of pollution contributors around the county.

In order to combat the toxic runoff in the future, Pritchard endorses measures such as residential rainwater capture for future irrigation.

"It saves you money, it saves you water. So that's one of the best things that residents can do for themselves…. Here in San Diego our storm-water system lays mostly dormant. It's only during these few rain events that we really see the negative effects in action."

The Department of Environmental Health has issued a warning regarding elevated bacterial levels in coastal waters and advises against swimming, surfing and diving activities for at least 72 hours following the end of the current rainfall.