Drain: Choosing a Surf Site After a Storm
by Lori Lambertson
Whats more exciting
for a surfer than having your boss ask you to surf as part of your
job? That's the situation I found myself in as the Exploratorium
geared up to add information about science and surfing to its Web
site. I needed to coordinate my surf date with a photographer, producer,
and videographer. As we got our calendars out to plan,
I realized that setting a date to surf isnt always straightforward.
heading out, Lori considers recent, as well as current weather.
Runoff from storms can leave pollutants in ocean water.
Seemingly, all I had
to do was pick a day that worked for everyone, but it was more complicated
than that. Of course I had to consider tides, waves, and weather.
But I also had to consider what the weather had been like in previous
Planning for the tide
was simple: I was looking for low tide, as the surf area we had
picked for our shoot usually breaks better on a low tide (for more
on how tides work and why theyre important for surfers, check
out our Dance of the Tides article). I
consulted my Tidelog (a book that shows the height of the tide,
graphically, for every day of the year) to find a low tide in the
middle of the day at our chosen beach near Santa Cruz (you can also
find on-line tidal information for anywhere in the United States
at the Saltwater
Tides Web site).
Finding a date with good weather and waves was a little trickier.
Surfers use a variety of resources to predict what days will bring
the best conditions. From the tide perspective, Wednesday looked
like a good bet. But weather reports from NOAA
(National Oceanic and Atmospheric Administration) indicated that
a storm would arrive that day.
We could see from our
surf forecast that we would likely
find decent waves on Sunday, but by Tuesday, the fun would probably
be over. With no swell on Tuesday and rain predicted for Wednesday,
we decided to change the date to Friday, with the caveat that we
might have to cancel if it continued to rain on Thursday. If were
planning to surf Friday, why should we care if it rains on Thursday?
A look at what happens to ocean water during a storm might shed
The Drain from Rain
Falls Mainly into the Nearby Ocean
and suburban communities, rain runs off impervious surfaces (which
include rooftops, sidewalks, driveways, parking lots, playgrounds,
streets, and highways). As runoff moves toward storm drains, it
picks up oil, garden and household chemicals, animal waste, bird
waste, litter, settled particulate matter, and other pollutants.
More densely populated areas usually have more impervious surfaces,
which results in more runoff.
and the pollutants it collects enter drains like this one
on city streets...
communities, runoff in storm drains is partially cleaned up at water-treatment
facilities, but often, it isnt treated at all, to some extent
because these facilities have limited capacity (it is also simpler
and cheaper to just let the storm-drain water flow into the local
watershed). So during and after a rainstorm, the runoff entering
storm drains may be diverted directly into the ocean. When you see
a storm drain with a sign that says, "Do not dump, flows to
ocean" stenciled on it, its a pretty good bet that the
water wont be treated. This untreated runoff is the most common
type of non-point source pollution (pollution that originates from
many different sources rather than one specific, identifiable source)
in our bays and oceans, and it presents a worldwide coastal-pollution
source pollution from motor vehicles and roadways may be the greatest
threat to the San Francisco Bay Areas water quality. Copper
from brake pads, cadmium from tires, oil and grease from engines,
and other fine particulates enter Bay Area streams, the San Francisco
Bay, and the ocean via surface-water runoff. Paved surfaces that
prevent rainwater and other runoff from filtering through the ground
increase the amount of urban pollutants entering watersheds and
waterways. To find out more about the non-point source pollution,
see the Surfrider
Foundation's Environmental index.
eventually dumps into the ocean through drainpipes like this
one, on a surfing beach.
for a Healthy Wave
What does all this mean to surfers? Many have become sick after
surfing in polluted water. Common illnesses include eye, ear, nose,
and throat infections, stomach problems, and skin rashes. To be
safe, lots of surfers stay out of the water for several days after
a storm. Over time, the concentration of pollutants in the surf
zone decreases, as tides, waves, and currents disperse the pollutants.
How do you know if the water is safe at your beach? The
Surfrider Foundation is dedicated to the protection and enjoyment
of the worlds oceans, waves, and beaches. Local chapters of
the Surfrider Foundation post regularly
updated water-quality data on their Web sites. The Surfrider
Foundation recommends avoiding water contact for two to three days
after the end of a rain event.
It rained on Wednesday. It was cloudy on Thursday. By Friday, the
pollutants in the surf zone had had some time to dissipate, and
we decided to go ahead with our plans because the weather, wave,
and water conditions were okay. You can view the photos and videos
from our surf session here. Do I have the best job or what?