Summer High Tides Sneaking UP

Business as usual—hard to believe this area could flood  |  photos and post by Jenny Stein

5-day tide chart shows high HIGH tides occurring mostly at night — graphic from the Army Corps of Engineers

Winter rains, saturated ground, and low-pressure systems all but guarantee flooding during a (winter) king tide  |  January 2016

The Big Question: how much flooding can we expect? The Answer: not enough to close the lot!

These newly-minted signs would indicate we should count on some flooding to occur

The Marin Airporter, and others, rely upon Caltrans to determine when the Manzanita lot is closed—or not

In the event of closure at Manzanita, Marin Airporter drivers will proceed to Seminary Drive (shown)

Or to Spencer Avenue (shown). Parking is limited to a 24-hour period at both Manzanita and Spencer Ave

This last week has been glorious. The dry heat of summer, with the forecast of blue skies stretching into June, signals that we’ve left the wet and cold of winter behind. What we haven’t quite escaped is the possibility of flooding at high tide. Over the next 5 days—starting Wednesday May 23 (high tide of 6’2″ at 9:30 p.m.) and peaking with a high tide of 6’6″ at midnight on Thursday May 25—we might expect flooding, but it won’t be enough for Caltrans to close the Manzanita lot.

Unlike in winter—when flooding is all but guaranteed—this period simply requires that you not park where signs indicate an area is prone to flooding. I spoke with Caltrans, who have us on their radar and will let the Floating Times know when a closure is expected. These closures will be advertised well in advance, and Caltrans will turn on the illuminated signs to give drivers fair warning. I’ve also met with the maintenance crew over at the yard opposite Manzanita, who inform me they never close the lot in summer. Summer flooding occurs at night, and at night there’s not enough traffic to warrant traffic control. Makes sense—the moon would be in the greatest proximity to us, and have the greatest pull, at night. Armed with this knowledge, if you leave your car overnight, be sure to park on the higher ground.

While Marin Transit has posted signs advising riders of their alternate pick up/drop off point (if SB over at the Buckeye Roadhouse, or NB at the Pomona lot, etc.), Marin Airporter bus drivers will continue to pick up and drop off until they encounter physical barriers (cones and such) put up by Caltrans. Know that Marin Airporter will not pick up or drop off at the Buckeye, or Pomona, but will simply drive on to the next pick up/drop off point. Either Seminary Drive or Spencer Ave, depending upon the direction of travel. Traveling in winter? Add an extra half-hour to accommodate this possibility.

To conclude, despite the new Park and Ride warning signs, there are no plans to close Manzanita for high tides, this month or next. The sky is NOT falling in. But do mind where you park your car.

addendum Turns out we can expect higher-than-usual tides for a few days following the May 25, 2017 new supermoon. As EarthSky explains a supermoon is when the full or (in this case) new moon closely aligns with perigee—or the closest point to Earth in the moon’s orbit. The next supermoon is the Dec 3 full supermoon.